1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 // Must be at least Windows Vista or Server 2008 to use InitOnceExecuteOnce
  26 #define _WIN32_WINNT 0x0600
  27 
  28 // no precompiled headers
  29 #include "classfile/classLoader.hpp"
  30 #include "classfile/systemDictionary.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "code/icBuffer.hpp"
  33 #include "code/vtableStubs.hpp"
  34 #include "compiler/compileBroker.hpp"
  35 #include "compiler/disassembler.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "jvm_windows.h"
  38 #include "logging/log.hpp"
  39 #include "memory/allocation.inline.hpp"
  40 #include "memory/filemap.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "os_share_windows.hpp"
  43 #include "os_windows.inline.hpp"
  44 #include "prims/jniFastGetField.hpp"
  45 #include "prims/jvm.h"
  46 #include "prims/jvm_misc.hpp"
  47 #include "runtime/arguments.hpp"
  48 #include "runtime/atomic.hpp"
  49 #include "runtime/extendedPC.hpp"
  50 #include "runtime/globals.hpp"
  51 #include "runtime/interfaceSupport.hpp"
  52 #include "runtime/java.hpp"
  53 #include "runtime/javaCalls.hpp"
  54 #include "runtime/mutexLocker.hpp"
  55 #include "runtime/objectMonitor.hpp"
  56 #include "runtime/orderAccess.inline.hpp"
  57 #include "runtime/osThread.hpp"
  58 #include "runtime/perfMemory.hpp"
  59 #include "runtime/sharedRuntime.hpp"
  60 #include "runtime/statSampler.hpp"
  61 #include "runtime/stubRoutines.hpp"
  62 #include "runtime/thread.inline.hpp"
  63 #include "runtime/threadCritical.hpp"
  64 #include "runtime/timer.hpp"
  65 #include "runtime/vm_version.hpp"
  66 #include "semaphore_windows.hpp"
  67 #include "services/attachListener.hpp"
  68 #include "services/memTracker.hpp"
  69 #include "services/runtimeService.hpp"
  70 #include "utilities/align.hpp"
  71 #include "utilities/decoder.hpp"
  72 #include "utilities/defaultStream.hpp"
  73 #include "utilities/events.hpp"
  74 #include "utilities/growableArray.hpp"
  75 #include "utilities/macros.hpp"
  76 #include "utilities/vmError.hpp"
  77 #include "symbolengine.hpp"
  78 #include "windbghelp.hpp"
  79 
  80 
  81 #ifdef _DEBUG
  82 #include <crtdbg.h>
  83 #endif
  84 
  85 
  86 #include <windows.h>
  87 #include <sys/types.h>
  88 #include <sys/stat.h>
  89 #include <sys/timeb.h>
  90 #include <objidl.h>
  91 #include <shlobj.h>
  92 
  93 #include <malloc.h>
  94 #include <signal.h>
  95 #include <direct.h>
  96 #include <errno.h>
  97 #include <fcntl.h>
  98 #include <io.h>
  99 #include <process.h>              // For _beginthreadex(), _endthreadex()
 100 #include <imagehlp.h>             // For os::dll_address_to_function_name
 101 // for enumerating dll libraries
 102 #include <vdmdbg.h>
 103 
 104 // for timer info max values which include all bits
 105 #define ALL_64_BITS CONST64(-1)
 106 
 107 // For DLL loading/load error detection
 108 // Values of PE COFF
 109 #define IMAGE_FILE_PTR_TO_SIGNATURE 0x3c
 110 #define IMAGE_FILE_SIGNATURE_LENGTH 4
 111 
 112 static HANDLE main_process;
 113 static HANDLE main_thread;
 114 static int    main_thread_id;
 115 
 116 static FILETIME process_creation_time;
 117 static FILETIME process_exit_time;
 118 static FILETIME process_user_time;
 119 static FILETIME process_kernel_time;
 120 
 121 #ifdef _M_AMD64
 122   #define __CPU__ amd64
 123 #else
 124   #define __CPU__ i486
 125 #endif
 126 
 127 // save DLL module handle, used by GetModuleFileName
 128 
 129 HINSTANCE vm_lib_handle;
 130 
 131 BOOL WINAPI DllMain(HINSTANCE hinst, DWORD reason, LPVOID reserved) {
 132   switch (reason) {
 133   case DLL_PROCESS_ATTACH:
 134     vm_lib_handle = hinst;
 135     if (ForceTimeHighResolution) {
 136       timeBeginPeriod(1L);
 137     }
 138     WindowsDbgHelp::pre_initialize();
 139     SymbolEngine::pre_initialize();
 140     break;
 141   case DLL_PROCESS_DETACH:
 142     if (ForceTimeHighResolution) {
 143       timeEndPeriod(1L);
 144     }
 145     break;
 146   default:
 147     break;
 148   }
 149   return true;
 150 }
 151 
 152 static inline double fileTimeAsDouble(FILETIME* time) {
 153   const double high  = (double) ((unsigned int) ~0);
 154   const double split = 10000000.0;
 155   double result = (time->dwLowDateTime / split) +
 156                    time->dwHighDateTime * (high/split);
 157   return result;
 158 }
 159 
 160 // Implementation of os
 161 
 162 bool os::unsetenv(const char* name) {
 163   assert(name != NULL, "Null pointer");
 164   return (SetEnvironmentVariable(name, NULL) == TRUE);
 165 }
 166 
 167 // No setuid programs under Windows.
 168 bool os::have_special_privileges() {
 169   return false;
 170 }
 171 
 172 
 173 // This method is  a periodic task to check for misbehaving JNI applications
 174 // under CheckJNI, we can add any periodic checks here.
 175 // For Windows at the moment does nothing
 176 void os::run_periodic_checks() {
 177   return;
 178 }
 179 
 180 // previous UnhandledExceptionFilter, if there is one
 181 static LPTOP_LEVEL_EXCEPTION_FILTER prev_uef_handler = NULL;
 182 
 183 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo);
 184 
 185 void os::init_system_properties_values() {
 186   // sysclasspath, java_home, dll_dir
 187   {
 188     char *home_path;
 189     char *dll_path;
 190     char *pslash;
 191     char *bin = "\\bin";
 192     char home_dir[MAX_PATH + 1];
 193     char *alt_home_dir = ::getenv("_ALT_JAVA_HOME_DIR");
 194 
 195     if (alt_home_dir != NULL)  {
 196       strncpy(home_dir, alt_home_dir, MAX_PATH + 1);
 197       home_dir[MAX_PATH] = '\0';
 198     } else {
 199       os::jvm_path(home_dir, sizeof(home_dir));
 200       // Found the full path to jvm.dll.
 201       // Now cut the path to <java_home>/jre if we can.
 202       *(strrchr(home_dir, '\\')) = '\0';  // get rid of \jvm.dll
 203       pslash = strrchr(home_dir, '\\');
 204       if (pslash != NULL) {
 205         *pslash = '\0';                   // get rid of \{client|server}
 206         pslash = strrchr(home_dir, '\\');
 207         if (pslash != NULL) {
 208           *pslash = '\0';                 // get rid of \bin
 209         }
 210       }
 211     }
 212 
 213     home_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + 1, mtInternal);
 214     if (home_path == NULL) {
 215       return;
 216     }
 217     strcpy(home_path, home_dir);
 218     Arguments::set_java_home(home_path);
 219     FREE_C_HEAP_ARRAY(char, home_path);
 220 
 221     dll_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + strlen(bin) + 1,
 222                                 mtInternal);
 223     if (dll_path == NULL) {
 224       return;
 225     }
 226     strcpy(dll_path, home_dir);
 227     strcat(dll_path, bin);
 228     Arguments::set_dll_dir(dll_path);
 229     FREE_C_HEAP_ARRAY(char, dll_path);
 230 
 231     if (!set_boot_path('\\', ';')) {
 232       return;
 233     }
 234   }
 235 
 236 // library_path
 237 #define EXT_DIR "\\lib\\ext"
 238 #define BIN_DIR "\\bin"
 239 #define PACKAGE_DIR "\\Sun\\Java"
 240   {
 241     // Win32 library search order (See the documentation for LoadLibrary):
 242     //
 243     // 1. The directory from which application is loaded.
 244     // 2. The system wide Java Extensions directory (Java only)
 245     // 3. System directory (GetSystemDirectory)
 246     // 4. Windows directory (GetWindowsDirectory)
 247     // 5. The PATH environment variable
 248     // 6. The current directory
 249 
 250     char *library_path;
 251     char tmp[MAX_PATH];
 252     char *path_str = ::getenv("PATH");
 253 
 254     library_path = NEW_C_HEAP_ARRAY(char, MAX_PATH * 5 + sizeof(PACKAGE_DIR) +
 255                                     sizeof(BIN_DIR) + (path_str ? strlen(path_str) : 0) + 10, mtInternal);
 256 
 257     library_path[0] = '\0';
 258 
 259     GetModuleFileName(NULL, tmp, sizeof(tmp));
 260     *(strrchr(tmp, '\\')) = '\0';
 261     strcat(library_path, tmp);
 262 
 263     GetWindowsDirectory(tmp, sizeof(tmp));
 264     strcat(library_path, ";");
 265     strcat(library_path, tmp);
 266     strcat(library_path, PACKAGE_DIR BIN_DIR);
 267 
 268     GetSystemDirectory(tmp, sizeof(tmp));
 269     strcat(library_path, ";");
 270     strcat(library_path, tmp);
 271 
 272     GetWindowsDirectory(tmp, sizeof(tmp));
 273     strcat(library_path, ";");
 274     strcat(library_path, tmp);
 275 
 276     if (path_str) {
 277       strcat(library_path, ";");
 278       strcat(library_path, path_str);
 279     }
 280 
 281     strcat(library_path, ";.");
 282 
 283     Arguments::set_library_path(library_path);
 284     FREE_C_HEAP_ARRAY(char, library_path);
 285   }
 286 
 287   // Default extensions directory
 288   {
 289     char path[MAX_PATH];
 290     char buf[2 * MAX_PATH + 2 * sizeof(EXT_DIR) + sizeof(PACKAGE_DIR) + 1];
 291     GetWindowsDirectory(path, MAX_PATH);
 292     sprintf(buf, "%s%s;%s%s%s", Arguments::get_java_home(), EXT_DIR,
 293             path, PACKAGE_DIR, EXT_DIR);
 294     Arguments::set_ext_dirs(buf);
 295   }
 296   #undef EXT_DIR
 297   #undef BIN_DIR
 298   #undef PACKAGE_DIR
 299 
 300 #ifndef _WIN64
 301   // set our UnhandledExceptionFilter and save any previous one
 302   prev_uef_handler = SetUnhandledExceptionFilter(Handle_FLT_Exception);
 303 #endif
 304 
 305   // Done
 306   return;
 307 }
 308 
 309 void os::breakpoint() {
 310   DebugBreak();
 311 }
 312 
 313 // Invoked from the BREAKPOINT Macro
 314 extern "C" void breakpoint() {
 315   os::breakpoint();
 316 }
 317 
 318 // RtlCaptureStackBackTrace Windows API may not exist prior to Windows XP.
 319 // So far, this method is only used by Native Memory Tracking, which is
 320 // only supported on Windows XP or later.
 321 //
 322 int os::get_native_stack(address* stack, int frames, int toSkip) {
 323   int captured = RtlCaptureStackBackTrace(toSkip + 1, frames, (PVOID*)stack, NULL);
 324   for (int index = captured; index < frames; index ++) {
 325     stack[index] = NULL;
 326   }
 327   return captured;
 328 }
 329 
 330 
 331 // os::current_stack_base()
 332 //
 333 //   Returns the base of the stack, which is the stack's
 334 //   starting address.  This function must be called
 335 //   while running on the stack of the thread being queried.
 336 
 337 address os::current_stack_base() {
 338   MEMORY_BASIC_INFORMATION minfo;
 339   address stack_bottom;
 340   size_t stack_size;
 341 
 342   VirtualQuery(&minfo, &minfo, sizeof(minfo));
 343   stack_bottom =  (address)minfo.AllocationBase;
 344   stack_size = minfo.RegionSize;
 345 
 346   // Add up the sizes of all the regions with the same
 347   // AllocationBase.
 348   while (1) {
 349     VirtualQuery(stack_bottom+stack_size, &minfo, sizeof(minfo));
 350     if (stack_bottom == (address)minfo.AllocationBase) {
 351       stack_size += minfo.RegionSize;
 352     } else {
 353       break;
 354     }
 355   }
 356   return stack_bottom + stack_size;
 357 }
 358 
 359 size_t os::current_stack_size() {
 360   size_t sz;
 361   MEMORY_BASIC_INFORMATION minfo;
 362   VirtualQuery(&minfo, &minfo, sizeof(minfo));
 363   sz = (size_t)os::current_stack_base() - (size_t)minfo.AllocationBase;
 364   return sz;
 365 }
 366 
 367 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
 368   const struct tm* time_struct_ptr = localtime(clock);
 369   if (time_struct_ptr != NULL) {
 370     *res = *time_struct_ptr;
 371     return res;
 372   }
 373   return NULL;
 374 }
 375 
 376 struct tm* os::gmtime_pd(const time_t* clock, struct tm* res) {
 377   const struct tm* time_struct_ptr = gmtime(clock);
 378   if (time_struct_ptr != NULL) {
 379     *res = *time_struct_ptr;
 380     return res;
 381   }
 382   return NULL;
 383 }
 384 
 385 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo);
 386 
 387 // Thread start routine for all newly created threads
 388 static unsigned __stdcall thread_native_entry(Thread* thread) {
 389   // Try to randomize the cache line index of hot stack frames.
 390   // This helps when threads of the same stack traces evict each other's
 391   // cache lines. The threads can be either from the same JVM instance, or
 392   // from different JVM instances. The benefit is especially true for
 393   // processors with hyperthreading technology.
 394   static int counter = 0;
 395   int pid = os::current_process_id();
 396   _alloca(((pid ^ counter++) & 7) * 128);
 397 
 398   thread->initialize_thread_current();
 399 
 400   OSThread* osthr = thread->osthread();
 401   assert(osthr->get_state() == RUNNABLE, "invalid os thread state");
 402 
 403   if (UseNUMA) {
 404     int lgrp_id = os::numa_get_group_id();
 405     if (lgrp_id != -1) {
 406       thread->set_lgrp_id(lgrp_id);
 407     }
 408   }
 409 
 410   // Diagnostic code to investigate JDK-6573254
 411   int res = 30115;  // non-java thread
 412   if (thread->is_Java_thread()) {
 413     res = 20115;    // java thread
 414   }
 415 
 416   log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ").", os::current_thread_id());
 417 
 418   // Install a win32 structured exception handler around every thread created
 419   // by VM, so VM can generate error dump when an exception occurred in non-
 420   // Java thread (e.g. VM thread).
 421   __try {
 422     thread->run();
 423   } __except(topLevelExceptionFilter(
 424                                      (_EXCEPTION_POINTERS*)_exception_info())) {
 425     // Nothing to do.
 426   }
 427 
 428   log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ").", os::current_thread_id());
 429 
 430   // One less thread is executing
 431   // When the VMThread gets here, the main thread may have already exited
 432   // which frees the CodeHeap containing the Atomic::add code
 433   if (thread != VMThread::vm_thread() && VMThread::vm_thread() != NULL) {
 434     Atomic::dec_ptr((intptr_t*)&os::win32::_os_thread_count);
 435   }
 436 
 437   // If a thread has not deleted itself ("delete this") as part of its
 438   // termination sequence, we have to ensure thread-local-storage is
 439   // cleared before we actually terminate. No threads should ever be
 440   // deleted asynchronously with respect to their termination.
 441   if (Thread::current_or_null_safe() != NULL) {
 442     assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
 443     thread->clear_thread_current();
 444   }
 445 
 446   // Thread must not return from exit_process_or_thread(), but if it does,
 447   // let it proceed to exit normally
 448   return (unsigned)os::win32::exit_process_or_thread(os::win32::EPT_THREAD, res);
 449 }
 450 
 451 static OSThread* create_os_thread(Thread* thread, HANDLE thread_handle,
 452                                   int thread_id) {
 453   // Allocate the OSThread object
 454   OSThread* osthread = new OSThread(NULL, NULL);
 455   if (osthread == NULL) return NULL;
 456 
 457   // Initialize support for Java interrupts
 458   HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
 459   if (interrupt_event == NULL) {
 460     delete osthread;
 461     return NULL;
 462   }
 463   osthread->set_interrupt_event(interrupt_event);
 464 
 465   // Store info on the Win32 thread into the OSThread
 466   osthread->set_thread_handle(thread_handle);
 467   osthread->set_thread_id(thread_id);
 468 
 469   if (UseNUMA) {
 470     int lgrp_id = os::numa_get_group_id();
 471     if (lgrp_id != -1) {
 472       thread->set_lgrp_id(lgrp_id);
 473     }
 474   }
 475 
 476   // Initial thread state is INITIALIZED, not SUSPENDED
 477   osthread->set_state(INITIALIZED);
 478 
 479   return osthread;
 480 }
 481 
 482 
 483 bool os::create_attached_thread(JavaThread* thread) {
 484 #ifdef ASSERT
 485   thread->verify_not_published();
 486 #endif
 487   HANDLE thread_h;
 488   if (!DuplicateHandle(main_process, GetCurrentThread(), GetCurrentProcess(),
 489                        &thread_h, THREAD_ALL_ACCESS, false, 0)) {
 490     fatal("DuplicateHandle failed\n");
 491   }
 492   OSThread* osthread = create_os_thread(thread, thread_h,
 493                                         (int)current_thread_id());
 494   if (osthread == NULL) {
 495     return false;
 496   }
 497 
 498   // Initial thread state is RUNNABLE
 499   osthread->set_state(RUNNABLE);
 500 
 501   thread->set_osthread(osthread);
 502 
 503   log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ").",
 504     os::current_thread_id());
 505 
 506   return true;
 507 }
 508 
 509 bool os::create_main_thread(JavaThread* thread) {
 510 #ifdef ASSERT
 511   thread->verify_not_published();
 512 #endif
 513   if (_starting_thread == NULL) {
 514     _starting_thread = create_os_thread(thread, main_thread, main_thread_id);
 515     if (_starting_thread == NULL) {
 516       return false;
 517     }
 518   }
 519 
 520   // The primordial thread is runnable from the start)
 521   _starting_thread->set_state(RUNNABLE);
 522 
 523   thread->set_osthread(_starting_thread);
 524   return true;
 525 }
 526 
 527 // Helper function to trace _beginthreadex attributes,
 528 //  similar to os::Posix::describe_pthread_attr()
 529 static char* describe_beginthreadex_attributes(char* buf, size_t buflen,
 530                                                size_t stacksize, unsigned initflag) {
 531   stringStream ss(buf, buflen);
 532   if (stacksize == 0) {
 533     ss.print("stacksize: default, ");
 534   } else {
 535     ss.print("stacksize: " SIZE_FORMAT "k, ", stacksize / 1024);
 536   }
 537   ss.print("flags: ");
 538   #define PRINT_FLAG(f) if (initflag & f) ss.print( #f " ");
 539   #define ALL(X) \
 540     X(CREATE_SUSPENDED) \
 541     X(STACK_SIZE_PARAM_IS_A_RESERVATION)
 542   ALL(PRINT_FLAG)
 543   #undef ALL
 544   #undef PRINT_FLAG
 545   return buf;
 546 }
 547 
 548 // Allocate and initialize a new OSThread
 549 bool os::create_thread(Thread* thread, ThreadType thr_type,
 550                        size_t stack_size) {
 551   unsigned thread_id;
 552 
 553   // Allocate the OSThread object
 554   OSThread* osthread = new OSThread(NULL, NULL);
 555   if (osthread == NULL) {
 556     return false;
 557   }
 558 
 559   // Initialize support for Java interrupts
 560   HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
 561   if (interrupt_event == NULL) {
 562     delete osthread;
 563     return NULL;
 564   }
 565   osthread->set_interrupt_event(interrupt_event);
 566   osthread->set_interrupted(false);
 567 
 568   thread->set_osthread(osthread);
 569 
 570   if (stack_size == 0) {
 571     switch (thr_type) {
 572     case os::java_thread:
 573       // Java threads use ThreadStackSize which default value can be changed with the flag -Xss
 574       if (JavaThread::stack_size_at_create() > 0) {
 575         stack_size = JavaThread::stack_size_at_create();
 576       }
 577       break;
 578     case os::compiler_thread:
 579       if (CompilerThreadStackSize > 0) {
 580         stack_size = (size_t)(CompilerThreadStackSize * K);
 581         break;
 582       } // else fall through:
 583         // use VMThreadStackSize if CompilerThreadStackSize is not defined
 584     case os::vm_thread:
 585     case os::pgc_thread:
 586     case os::cgc_thread:
 587     case os::watcher_thread:
 588       if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
 589       break;
 590     }
 591   }
 592 
 593   // Create the Win32 thread
 594   //
 595   // Contrary to what MSDN document says, "stack_size" in _beginthreadex()
 596   // does not specify stack size. Instead, it specifies the size of
 597   // initially committed space. The stack size is determined by
 598   // PE header in the executable. If the committed "stack_size" is larger
 599   // than default value in the PE header, the stack is rounded up to the
 600   // nearest multiple of 1MB. For example if the launcher has default
 601   // stack size of 320k, specifying any size less than 320k does not
 602   // affect the actual stack size at all, it only affects the initial
 603   // commitment. On the other hand, specifying 'stack_size' larger than
 604   // default value may cause significant increase in memory usage, because
 605   // not only the stack space will be rounded up to MB, but also the
 606   // entire space is committed upfront.
 607   //
 608   // Finally Windows XP added a new flag 'STACK_SIZE_PARAM_IS_A_RESERVATION'
 609   // for CreateThread() that can treat 'stack_size' as stack size. However we
 610   // are not supposed to call CreateThread() directly according to MSDN
 611   // document because JVM uses C runtime library. The good news is that the
 612   // flag appears to work with _beginthredex() as well.
 613 
 614   const unsigned initflag = CREATE_SUSPENDED | STACK_SIZE_PARAM_IS_A_RESERVATION;
 615   HANDLE thread_handle =
 616     (HANDLE)_beginthreadex(NULL,
 617                            (unsigned)stack_size,
 618                            (unsigned (__stdcall *)(void*)) thread_native_entry,
 619                            thread,
 620                            initflag,
 621                            &thread_id);
 622 
 623   char buf[64];
 624   if (thread_handle != NULL) {
 625     log_info(os, thread)("Thread started (tid: %u, attributes: %s)",
 626       thread_id, describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
 627   } else {
 628     log_warning(os, thread)("Failed to start thread - _beginthreadex failed (%s) for attributes: %s.",
 629       os::errno_name(errno), describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
 630   }
 631 
 632   if (thread_handle == NULL) {
 633     // Need to clean up stuff we've allocated so far
 634     CloseHandle(osthread->interrupt_event());
 635     thread->set_osthread(NULL);
 636     delete osthread;
 637     return NULL;
 638   }
 639 
 640   Atomic::inc_ptr((intptr_t*)&os::win32::_os_thread_count);
 641 
 642   // Store info on the Win32 thread into the OSThread
 643   osthread->set_thread_handle(thread_handle);
 644   osthread->set_thread_id(thread_id);
 645 
 646   // Initial thread state is INITIALIZED, not SUSPENDED
 647   osthread->set_state(INITIALIZED);
 648 
 649   // The thread is returned suspended (in state INITIALIZED), and is started higher up in the call chain
 650   return true;
 651 }
 652 
 653 
 654 // Free Win32 resources related to the OSThread
 655 void os::free_thread(OSThread* osthread) {
 656   assert(osthread != NULL, "osthread not set");
 657 
 658   // We are told to free resources of the argument thread,
 659   // but we can only really operate on the current thread.
 660   assert(Thread::current()->osthread() == osthread,
 661          "os::free_thread but not current thread");
 662 
 663   CloseHandle(osthread->thread_handle());
 664   CloseHandle(osthread->interrupt_event());
 665   delete osthread;
 666 }
 667 
 668 static jlong first_filetime;
 669 static jlong initial_performance_count;
 670 static jlong performance_frequency;
 671 
 672 
 673 jlong as_long(LARGE_INTEGER x) {
 674   jlong result = 0; // initialization to avoid warning
 675   set_high(&result, x.HighPart);
 676   set_low(&result, x.LowPart);
 677   return result;
 678 }
 679 
 680 
 681 jlong os::elapsed_counter() {
 682   LARGE_INTEGER count;
 683   QueryPerformanceCounter(&count);
 684   return as_long(count) - initial_performance_count;
 685 }
 686 
 687 
 688 jlong os::elapsed_frequency() {
 689   return performance_frequency;
 690 }
 691 
 692 
 693 julong os::available_memory() {
 694   return win32::available_memory();
 695 }
 696 
 697 julong os::win32::available_memory() {
 698   // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
 699   // value if total memory is larger than 4GB
 700   MEMORYSTATUSEX ms;
 701   ms.dwLength = sizeof(ms);
 702   GlobalMemoryStatusEx(&ms);
 703 
 704   return (julong)ms.ullAvailPhys;
 705 }
 706 
 707 julong os::physical_memory() {
 708   return win32::physical_memory();
 709 }
 710 
 711 bool os::has_allocatable_memory_limit(julong* limit) {
 712   MEMORYSTATUSEX ms;
 713   ms.dwLength = sizeof(ms);
 714   GlobalMemoryStatusEx(&ms);
 715 #ifdef _LP64
 716   *limit = (julong)ms.ullAvailVirtual;
 717   return true;
 718 #else
 719   // Limit to 1400m because of the 2gb address space wall
 720   *limit = MIN2((julong)1400*M, (julong)ms.ullAvailVirtual);
 721   return true;
 722 #endif
 723 }
 724 
 725 int os::active_processor_count() {
 726   DWORD_PTR lpProcessAffinityMask = 0;
 727   DWORD_PTR lpSystemAffinityMask = 0;
 728   int proc_count = processor_count();
 729   if (proc_count <= sizeof(UINT_PTR) * BitsPerByte &&
 730       GetProcessAffinityMask(GetCurrentProcess(), &lpProcessAffinityMask, &lpSystemAffinityMask)) {
 731     // Nof active processors is number of bits in process affinity mask
 732     int bitcount = 0;
 733     while (lpProcessAffinityMask != 0) {
 734       lpProcessAffinityMask = lpProcessAffinityMask & (lpProcessAffinityMask-1);
 735       bitcount++;
 736     }
 737     return bitcount;
 738   } else {
 739     return proc_count;
 740   }
 741 }
 742 
 743 void os::set_native_thread_name(const char *name) {
 744 
 745   // See: http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx
 746   //
 747   // Note that unfortunately this only works if the process
 748   // is already attached to a debugger; debugger must observe
 749   // the exception below to show the correct name.
 750 
 751   // If there is no debugger attached skip raising the exception
 752   if (!IsDebuggerPresent()) {
 753     return;
 754   }
 755 
 756   const DWORD MS_VC_EXCEPTION = 0x406D1388;
 757   struct {
 758     DWORD dwType;     // must be 0x1000
 759     LPCSTR szName;    // pointer to name (in user addr space)
 760     DWORD dwThreadID; // thread ID (-1=caller thread)
 761     DWORD dwFlags;    // reserved for future use, must be zero
 762   } info;
 763 
 764   info.dwType = 0x1000;
 765   info.szName = name;
 766   info.dwThreadID = -1;
 767   info.dwFlags = 0;
 768 
 769   __try {
 770     RaiseException (MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (const ULONG_PTR*)&info );
 771   } __except(EXCEPTION_EXECUTE_HANDLER) {}
 772 }
 773 
 774 bool os::distribute_processes(uint length, uint* distribution) {
 775   // Not yet implemented.
 776   return false;
 777 }
 778 
 779 bool os::bind_to_processor(uint processor_id) {
 780   // Not yet implemented.
 781   return false;
 782 }
 783 
 784 void os::win32::initialize_performance_counter() {
 785   LARGE_INTEGER count;
 786   QueryPerformanceFrequency(&count);
 787   performance_frequency = as_long(count);
 788   QueryPerformanceCounter(&count);
 789   initial_performance_count = as_long(count);
 790 }
 791 
 792 
 793 double os::elapsedTime() {
 794   return (double) elapsed_counter() / (double) elapsed_frequency();
 795 }
 796 
 797 
 798 // Windows format:
 799 //   The FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601.
 800 // Java format:
 801 //   Java standards require the number of milliseconds since 1/1/1970
 802 
 803 // Constant offset - calculated using offset()
 804 static jlong  _offset   = 116444736000000000;
 805 // Fake time counter for reproducible results when debugging
 806 static jlong  fake_time = 0;
 807 
 808 #ifdef ASSERT
 809 // Just to be safe, recalculate the offset in debug mode
 810 static jlong _calculated_offset = 0;
 811 static int   _has_calculated_offset = 0;
 812 
 813 jlong offset() {
 814   if (_has_calculated_offset) return _calculated_offset;
 815   SYSTEMTIME java_origin;
 816   java_origin.wYear          = 1970;
 817   java_origin.wMonth         = 1;
 818   java_origin.wDayOfWeek     = 0; // ignored
 819   java_origin.wDay           = 1;
 820   java_origin.wHour          = 0;
 821   java_origin.wMinute        = 0;
 822   java_origin.wSecond        = 0;
 823   java_origin.wMilliseconds  = 0;
 824   FILETIME jot;
 825   if (!SystemTimeToFileTime(&java_origin, &jot)) {
 826     fatal("Error = %d\nWindows error", GetLastError());
 827   }
 828   _calculated_offset = jlong_from(jot.dwHighDateTime, jot.dwLowDateTime);
 829   _has_calculated_offset = 1;
 830   assert(_calculated_offset == _offset, "Calculated and constant time offsets must be equal");
 831   return _calculated_offset;
 832 }
 833 #else
 834 jlong offset() {
 835   return _offset;
 836 }
 837 #endif
 838 
 839 jlong windows_to_java_time(FILETIME wt) {
 840   jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
 841   return (a - offset()) / 10000;
 842 }
 843 
 844 // Returns time ticks in (10th of micro seconds)
 845 jlong windows_to_time_ticks(FILETIME wt) {
 846   jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
 847   return (a - offset());
 848 }
 849 
 850 FILETIME java_to_windows_time(jlong l) {
 851   jlong a = (l * 10000) + offset();
 852   FILETIME result;
 853   result.dwHighDateTime = high(a);
 854   result.dwLowDateTime  = low(a);
 855   return result;
 856 }
 857 
 858 bool os::supports_vtime() { return true; }
 859 bool os::enable_vtime() { return false; }
 860 bool os::vtime_enabled() { return false; }
 861 
 862 double os::elapsedVTime() {
 863   FILETIME created;
 864   FILETIME exited;
 865   FILETIME kernel;
 866   FILETIME user;
 867   if (GetThreadTimes(GetCurrentThread(), &created, &exited, &kernel, &user) != 0) {
 868     // the resolution of windows_to_java_time() should be sufficient (ms)
 869     return (double) (windows_to_java_time(kernel) + windows_to_java_time(user)) / MILLIUNITS;
 870   } else {
 871     return elapsedTime();
 872   }
 873 }
 874 
 875 jlong os::javaTimeMillis() {
 876   if (UseFakeTimers) {
 877     return fake_time++;
 878   } else {
 879     FILETIME wt;
 880     GetSystemTimeAsFileTime(&wt);
 881     return windows_to_java_time(wt);
 882   }
 883 }
 884 
 885 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
 886   FILETIME wt;
 887   GetSystemTimeAsFileTime(&wt);
 888   jlong ticks = windows_to_time_ticks(wt); // 10th of micros
 889   jlong secs = jlong(ticks / 10000000); // 10000 * 1000
 890   seconds = secs;
 891   nanos = jlong(ticks - (secs*10000000)) * 100;
 892 }
 893 
 894 jlong os::javaTimeNanos() {
 895     LARGE_INTEGER current_count;
 896     QueryPerformanceCounter(&current_count);
 897     double current = as_long(current_count);
 898     double freq = performance_frequency;
 899     jlong time = (jlong)((current/freq) * NANOSECS_PER_SEC);
 900     return time;
 901 }
 902 
 903 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
 904   jlong freq = performance_frequency;
 905   if (freq < NANOSECS_PER_SEC) {
 906     // the performance counter is 64 bits and we will
 907     // be multiplying it -- so no wrap in 64 bits
 908     info_ptr->max_value = ALL_64_BITS;
 909   } else if (freq > NANOSECS_PER_SEC) {
 910     // use the max value the counter can reach to
 911     // determine the max value which could be returned
 912     julong max_counter = (julong)ALL_64_BITS;
 913     info_ptr->max_value = (jlong)(max_counter / (freq / NANOSECS_PER_SEC));
 914   } else {
 915     // the performance counter is 64 bits and we will
 916     // be using it directly -- so no wrap in 64 bits
 917     info_ptr->max_value = ALL_64_BITS;
 918   }
 919 
 920   // using a counter, so no skipping
 921   info_ptr->may_skip_backward = false;
 922   info_ptr->may_skip_forward = false;
 923 
 924   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
 925 }
 926 
 927 char* os::local_time_string(char *buf, size_t buflen) {
 928   SYSTEMTIME st;
 929   GetLocalTime(&st);
 930   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
 931                st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
 932   return buf;
 933 }
 934 
 935 bool os::getTimesSecs(double* process_real_time,
 936                       double* process_user_time,
 937                       double* process_system_time) {
 938   HANDLE h_process = GetCurrentProcess();
 939   FILETIME create_time, exit_time, kernel_time, user_time;
 940   BOOL result = GetProcessTimes(h_process,
 941                                 &create_time,
 942                                 &exit_time,
 943                                 &kernel_time,
 944                                 &user_time);
 945   if (result != 0) {
 946     FILETIME wt;
 947     GetSystemTimeAsFileTime(&wt);
 948     jlong rtc_millis = windows_to_java_time(wt);
 949     *process_real_time = ((double) rtc_millis) / ((double) MILLIUNITS);
 950     *process_user_time =
 951       (double) jlong_from(user_time.dwHighDateTime, user_time.dwLowDateTime) / (10 * MICROUNITS);
 952     *process_system_time =
 953       (double) jlong_from(kernel_time.dwHighDateTime, kernel_time.dwLowDateTime) / (10 * MICROUNITS);
 954     return true;
 955   } else {
 956     return false;
 957   }
 958 }
 959 
 960 void os::shutdown() {
 961   // allow PerfMemory to attempt cleanup of any persistent resources
 962   perfMemory_exit();
 963 
 964   // flush buffered output, finish log files
 965   ostream_abort();
 966 
 967   // Check for abort hook
 968   abort_hook_t abort_hook = Arguments::abort_hook();
 969   if (abort_hook != NULL) {
 970     abort_hook();
 971   }
 972 }
 973 
 974 
 975 static BOOL (WINAPI *_MiniDumpWriteDump)(HANDLE, DWORD, HANDLE, MINIDUMP_TYPE,
 976                                          PMINIDUMP_EXCEPTION_INFORMATION,
 977                                          PMINIDUMP_USER_STREAM_INFORMATION,
 978                                          PMINIDUMP_CALLBACK_INFORMATION);
 979 
 980 static HANDLE dumpFile = NULL;
 981 
 982 // Check if dump file can be created.
 983 void os::check_dump_limit(char* buffer, size_t buffsz) {
 984   bool status = true;
 985   if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && !CreateCoredumpOnCrash) {
 986     jio_snprintf(buffer, buffsz, "CreateCoredumpOnCrash is disabled from command line");
 987     status = false;
 988   }
 989 
 990 #ifndef ASSERT
 991   if (!os::win32::is_windows_server() && FLAG_IS_DEFAULT(CreateCoredumpOnCrash)) {
 992     jio_snprintf(buffer, buffsz, "Minidumps are not enabled by default on client versions of Windows");
 993     status = false;
 994   }
 995 #endif
 996 
 997   if (status) {
 998     const char* cwd = get_current_directory(NULL, 0);
 999     int pid = current_process_id();
1000     if (cwd != NULL) {
1001       jio_snprintf(buffer, buffsz, "%s\\hs_err_pid%u.mdmp", cwd, pid);
1002     } else {
1003       jio_snprintf(buffer, buffsz, ".\\hs_err_pid%u.mdmp", pid);
1004     }
1005 
1006     if (dumpFile == NULL &&
1007        (dumpFile = CreateFile(buffer, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
1008                  == INVALID_HANDLE_VALUE) {
1009       jio_snprintf(buffer, buffsz, "Failed to create minidump file (0x%x).", GetLastError());
1010       status = false;
1011     }
1012   }
1013   VMError::record_coredump_status(buffer, status);
1014 }
1015 
1016 void os::abort(bool dump_core, void* siginfo, const void* context) {
1017   EXCEPTION_POINTERS ep;
1018   MINIDUMP_EXCEPTION_INFORMATION mei;
1019   MINIDUMP_EXCEPTION_INFORMATION* pmei;
1020 
1021   HANDLE hProcess = GetCurrentProcess();
1022   DWORD processId = GetCurrentProcessId();
1023   MINIDUMP_TYPE dumpType;
1024 
1025   shutdown();
1026   if (!dump_core || dumpFile == NULL) {
1027     if (dumpFile != NULL) {
1028       CloseHandle(dumpFile);
1029     }
1030     win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1031   }
1032 
1033   dumpType = (MINIDUMP_TYPE)(MiniDumpWithFullMemory | MiniDumpWithHandleData |
1034     MiniDumpWithFullMemoryInfo | MiniDumpWithThreadInfo | MiniDumpWithUnloadedModules);
1035 
1036   if (siginfo != NULL && context != NULL) {
1037     ep.ContextRecord = (PCONTEXT) context;
1038     ep.ExceptionRecord = (PEXCEPTION_RECORD) siginfo;
1039 
1040     mei.ThreadId = GetCurrentThreadId();
1041     mei.ExceptionPointers = &ep;
1042     pmei = &mei;
1043   } else {
1044     pmei = NULL;
1045   }
1046 
1047   // Older versions of dbghelp.dll (the one shipped with Win2003 for example) may not support all
1048   // the dump types we really want. If first call fails, lets fall back to just use MiniDumpWithFullMemory then.
1049   if (!WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, dumpType, pmei, NULL, NULL) &&
1050       !WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, (MINIDUMP_TYPE)MiniDumpWithFullMemory, pmei, NULL, NULL)) {
1051     jio_fprintf(stderr, "Call to MiniDumpWriteDump() failed (Error 0x%x)\n", GetLastError());
1052   }
1053   CloseHandle(dumpFile);
1054   win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1055 }
1056 
1057 // Die immediately, no exit hook, no abort hook, no cleanup.
1058 void os::die() {
1059   win32::exit_process_or_thread(win32::EPT_PROCESS_DIE, -1);
1060 }
1061 
1062 // Directory routines copied from src/win32/native/java/io/dirent_md.c
1063 //  * dirent_md.c       1.15 00/02/02
1064 //
1065 // The declarations for DIR and struct dirent are in jvm_win32.h.
1066 
1067 // Caller must have already run dirname through JVM_NativePath, which removes
1068 // duplicate slashes and converts all instances of '/' into '\\'.
1069 
1070 DIR * os::opendir(const char *dirname) {
1071   assert(dirname != NULL, "just checking");   // hotspot change
1072   DIR *dirp = (DIR *)malloc(sizeof(DIR), mtInternal);
1073   DWORD fattr;                                // hotspot change
1074   char alt_dirname[4] = { 0, 0, 0, 0 };
1075 
1076   if (dirp == 0) {
1077     errno = ENOMEM;
1078     return 0;
1079   }
1080 
1081   // Win32 accepts "\" in its POSIX stat(), but refuses to treat it
1082   // as a directory in FindFirstFile().  We detect this case here and
1083   // prepend the current drive name.
1084   //
1085   if (dirname[1] == '\0' && dirname[0] == '\\') {
1086     alt_dirname[0] = _getdrive() + 'A' - 1;
1087     alt_dirname[1] = ':';
1088     alt_dirname[2] = '\\';
1089     alt_dirname[3] = '\0';
1090     dirname = alt_dirname;
1091   }
1092 
1093   dirp->path = (char *)malloc(strlen(dirname) + 5, mtInternal);
1094   if (dirp->path == 0) {
1095     free(dirp);
1096     errno = ENOMEM;
1097     return 0;
1098   }
1099   strcpy(dirp->path, dirname);
1100 
1101   fattr = GetFileAttributes(dirp->path);
1102   if (fattr == 0xffffffff) {
1103     free(dirp->path);
1104     free(dirp);
1105     errno = ENOENT;
1106     return 0;
1107   } else if ((fattr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
1108     free(dirp->path);
1109     free(dirp);
1110     errno = ENOTDIR;
1111     return 0;
1112   }
1113 
1114   // Append "*.*", or possibly "\\*.*", to path
1115   if (dirp->path[1] == ':' &&
1116       (dirp->path[2] == '\0' ||
1117       (dirp->path[2] == '\\' && dirp->path[3] == '\0'))) {
1118     // No '\\' needed for cases like "Z:" or "Z:\"
1119     strcat(dirp->path, "*.*");
1120   } else {
1121     strcat(dirp->path, "\\*.*");
1122   }
1123 
1124   dirp->handle = FindFirstFile(dirp->path, &dirp->find_data);
1125   if (dirp->handle == INVALID_HANDLE_VALUE) {
1126     if (GetLastError() != ERROR_FILE_NOT_FOUND) {
1127       free(dirp->path);
1128       free(dirp);
1129       errno = EACCES;
1130       return 0;
1131     }
1132   }
1133   return dirp;
1134 }
1135 
1136 // parameter dbuf unused on Windows
1137 struct dirent * os::readdir(DIR *dirp, dirent *dbuf) {
1138   assert(dirp != NULL, "just checking");      // hotspot change
1139   if (dirp->handle == INVALID_HANDLE_VALUE) {
1140     return 0;
1141   }
1142 
1143   strcpy(dirp->dirent.d_name, dirp->find_data.cFileName);
1144 
1145   if (!FindNextFile(dirp->handle, &dirp->find_data)) {
1146     if (GetLastError() == ERROR_INVALID_HANDLE) {
1147       errno = EBADF;
1148       return 0;
1149     }
1150     FindClose(dirp->handle);
1151     dirp->handle = INVALID_HANDLE_VALUE;
1152   }
1153 
1154   return &dirp->dirent;
1155 }
1156 
1157 int os::closedir(DIR *dirp) {
1158   assert(dirp != NULL, "just checking");      // hotspot change
1159   if (dirp->handle != INVALID_HANDLE_VALUE) {
1160     if (!FindClose(dirp->handle)) {
1161       errno = EBADF;
1162       return -1;
1163     }
1164     dirp->handle = INVALID_HANDLE_VALUE;
1165   }
1166   free(dirp->path);
1167   free(dirp);
1168   return 0;
1169 }
1170 
1171 // This must be hard coded because it's the system's temporary
1172 // directory not the java application's temp directory, ala java.io.tmpdir.
1173 const char* os::get_temp_directory() {
1174   static char path_buf[MAX_PATH];
1175   if (GetTempPath(MAX_PATH, path_buf) > 0) {
1176     return path_buf;
1177   } else {
1178     path_buf[0] = '\0';
1179     return path_buf;
1180   }
1181 }
1182 
1183 // Needs to be in os specific directory because windows requires another
1184 // header file <direct.h>
1185 const char* os::get_current_directory(char *buf, size_t buflen) {
1186   int n = static_cast<int>(buflen);
1187   if (buflen > INT_MAX)  n = INT_MAX;
1188   return _getcwd(buf, n);
1189 }
1190 
1191 //-----------------------------------------------------------
1192 // Helper functions for fatal error handler
1193 #ifdef _WIN64
1194 // Helper routine which returns true if address in
1195 // within the NTDLL address space.
1196 //
1197 static bool _addr_in_ntdll(address addr) {
1198   HMODULE hmod;
1199   MODULEINFO minfo;
1200 
1201   hmod = GetModuleHandle("NTDLL.DLL");
1202   if (hmod == NULL) return false;
1203   if (!GetModuleInformation(GetCurrentProcess(), hmod,
1204                                           &minfo, sizeof(MODULEINFO))) {
1205     return false;
1206   }
1207 
1208   if ((addr >= minfo.lpBaseOfDll) &&
1209       (addr < (address)((uintptr_t)minfo.lpBaseOfDll + (uintptr_t)minfo.SizeOfImage))) {
1210     return true;
1211   } else {
1212     return false;
1213   }
1214 }
1215 #endif
1216 
1217 struct _modinfo {
1218   address addr;
1219   char*   full_path;   // point to a char buffer
1220   int     buflen;      // size of the buffer
1221   address base_addr;
1222 };
1223 
1224 static int _locate_module_by_addr(const char * mod_fname, address base_addr,
1225                                   address top_address, void * param) {
1226   struct _modinfo *pmod = (struct _modinfo *)param;
1227   if (!pmod) return -1;
1228 
1229   if (base_addr   <= pmod->addr &&
1230       top_address > pmod->addr) {
1231     // if a buffer is provided, copy path name to the buffer
1232     if (pmod->full_path) {
1233       jio_snprintf(pmod->full_path, pmod->buflen, "%s", mod_fname);
1234     }
1235     pmod->base_addr = base_addr;
1236     return 1;
1237   }
1238   return 0;
1239 }
1240 
1241 bool os::dll_address_to_library_name(address addr, char* buf,
1242                                      int buflen, int* offset) {
1243   // buf is not optional, but offset is optional
1244   assert(buf != NULL, "sanity check");
1245 
1246 // NOTE: the reason we don't use SymGetModuleInfo() is it doesn't always
1247 //       return the full path to the DLL file, sometimes it returns path
1248 //       to the corresponding PDB file (debug info); sometimes it only
1249 //       returns partial path, which makes life painful.
1250 
1251   struct _modinfo mi;
1252   mi.addr      = addr;
1253   mi.full_path = buf;
1254   mi.buflen    = buflen;
1255   if (get_loaded_modules_info(_locate_module_by_addr, (void *)&mi)) {
1256     // buf already contains path name
1257     if (offset) *offset = addr - mi.base_addr;
1258     return true;
1259   }
1260 
1261   buf[0] = '\0';
1262   if (offset) *offset = -1;
1263   return false;
1264 }
1265 
1266 bool os::dll_address_to_function_name(address addr, char *buf,
1267                                       int buflen, int *offset,
1268                                       bool demangle) {
1269   // buf is not optional, but offset is optional
1270   assert(buf != NULL, "sanity check");
1271 
1272   if (Decoder::decode(addr, buf, buflen, offset, demangle)) {
1273     return true;
1274   }
1275   if (offset != NULL)  *offset  = -1;
1276   buf[0] = '\0';
1277   return false;
1278 }
1279 
1280 // save the start and end address of jvm.dll into param[0] and param[1]
1281 static int _locate_jvm_dll(const char* mod_fname, address base_addr,
1282                            address top_address, void * param) {
1283   if (!param) return -1;
1284 
1285   if (base_addr   <= (address)_locate_jvm_dll &&
1286       top_address > (address)_locate_jvm_dll) {
1287     ((address*)param)[0] = base_addr;
1288     ((address*)param)[1] = top_address;
1289     return 1;
1290   }
1291   return 0;
1292 }
1293 
1294 address vm_lib_location[2];    // start and end address of jvm.dll
1295 
1296 // check if addr is inside jvm.dll
1297 bool os::address_is_in_vm(address addr) {
1298   if (!vm_lib_location[0] || !vm_lib_location[1]) {
1299     if (!get_loaded_modules_info(_locate_jvm_dll, (void *)vm_lib_location)) {
1300       assert(false, "Can't find jvm module.");
1301       return false;
1302     }
1303   }
1304 
1305   return (vm_lib_location[0] <= addr) && (addr < vm_lib_location[1]);
1306 }
1307 
1308 // print module info; param is outputStream*
1309 static int _print_module(const char* fname, address base_address,
1310                          address top_address, void* param) {
1311   if (!param) return -1;
1312 
1313   outputStream* st = (outputStream*)param;
1314 
1315   st->print(PTR_FORMAT " - " PTR_FORMAT " \t%s\n", base_address, top_address, fname);
1316   return 0;
1317 }
1318 
1319 // Loads .dll/.so and
1320 // in case of error it checks if .dll/.so was built for the
1321 // same architecture as Hotspot is running on
1322 void * os::dll_load(const char *name, char *ebuf, int ebuflen) {
1323   void * result = LoadLibrary(name);
1324   if (result != NULL) {
1325     if (InitializeDbgHelpEarly) {
1326       // Recalculate pdb search path if a DLL was loaded successfully.
1327       SymbolEngine::recalc_search_path();
1328     }
1329     return result;
1330   }
1331 
1332   DWORD errcode = GetLastError();
1333   if (errcode == ERROR_MOD_NOT_FOUND) {
1334     strncpy(ebuf, "Can't find dependent libraries", ebuflen - 1);
1335     ebuf[ebuflen - 1] = '\0';
1336     return NULL;
1337   }
1338 
1339   // Parsing dll below
1340   // If we can read dll-info and find that dll was built
1341   // for an architecture other than Hotspot is running in
1342   // - then print to buffer "DLL was built for a different architecture"
1343   // else call os::lasterror to obtain system error message
1344 
1345   // Read system error message into ebuf
1346   // It may or may not be overwritten below (in the for loop and just above)
1347   lasterror(ebuf, (size_t) ebuflen);
1348   ebuf[ebuflen - 1] = '\0';
1349   int fd = ::open(name, O_RDONLY | O_BINARY, 0);
1350   if (fd < 0) {
1351     return NULL;
1352   }
1353 
1354   uint32_t signature_offset;
1355   uint16_t lib_arch = 0;
1356   bool failed_to_get_lib_arch =
1357     ( // Go to position 3c in the dll
1358      (os::seek_to_file_offset(fd, IMAGE_FILE_PTR_TO_SIGNATURE) < 0)
1359      ||
1360      // Read location of signature
1361      (sizeof(signature_offset) !=
1362      (os::read(fd, (void*)&signature_offset, sizeof(signature_offset))))
1363      ||
1364      // Go to COFF File Header in dll
1365      // that is located after "signature" (4 bytes long)
1366      (os::seek_to_file_offset(fd,
1367      signature_offset + IMAGE_FILE_SIGNATURE_LENGTH) < 0)
1368      ||
1369      // Read field that contains code of architecture
1370      // that dll was built for
1371      (sizeof(lib_arch) != (os::read(fd, (void*)&lib_arch, sizeof(lib_arch))))
1372     );
1373 
1374   ::close(fd);
1375   if (failed_to_get_lib_arch) {
1376     // file i/o error - report os::lasterror(...) msg
1377     return NULL;
1378   }
1379 
1380   typedef struct {
1381     uint16_t arch_code;
1382     char* arch_name;
1383   } arch_t;
1384 
1385   static const arch_t arch_array[] = {
1386     {IMAGE_FILE_MACHINE_I386,      (char*)"IA 32"},
1387     {IMAGE_FILE_MACHINE_AMD64,     (char*)"AMD 64"}
1388   };
1389 #if (defined _M_AMD64)
1390   static const uint16_t running_arch = IMAGE_FILE_MACHINE_AMD64;
1391 #elif (defined _M_IX86)
1392   static const uint16_t running_arch = IMAGE_FILE_MACHINE_I386;
1393 #else
1394   #error Method os::dll_load requires that one of following \
1395          is defined :_M_AMD64 or _M_IX86
1396 #endif
1397 
1398 
1399   // Obtain a string for printf operation
1400   // lib_arch_str shall contain string what platform this .dll was built for
1401   // running_arch_str shall string contain what platform Hotspot was built for
1402   char *running_arch_str = NULL, *lib_arch_str = NULL;
1403   for (unsigned int i = 0; i < ARRAY_SIZE(arch_array); i++) {
1404     if (lib_arch == arch_array[i].arch_code) {
1405       lib_arch_str = arch_array[i].arch_name;
1406     }
1407     if (running_arch == arch_array[i].arch_code) {
1408       running_arch_str = arch_array[i].arch_name;
1409     }
1410   }
1411 
1412   assert(running_arch_str,
1413          "Didn't find running architecture code in arch_array");
1414 
1415   // If the architecture is right
1416   // but some other error took place - report os::lasterror(...) msg
1417   if (lib_arch == running_arch) {
1418     return NULL;
1419   }
1420 
1421   if (lib_arch_str != NULL) {
1422     ::_snprintf(ebuf, ebuflen - 1,
1423                 "Can't load %s-bit .dll on a %s-bit platform",
1424                 lib_arch_str, running_arch_str);
1425   } else {
1426     // don't know what architecture this dll was build for
1427     ::_snprintf(ebuf, ebuflen - 1,
1428                 "Can't load this .dll (machine code=0x%x) on a %s-bit platform",
1429                 lib_arch, running_arch_str);
1430   }
1431 
1432   return NULL;
1433 }
1434 
1435 void os::print_dll_info(outputStream *st) {
1436   st->print_cr("Dynamic libraries:");
1437   get_loaded_modules_info(_print_module, (void *)st);
1438 }
1439 
1440 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1441   HANDLE   hProcess;
1442 
1443 # define MAX_NUM_MODULES 128
1444   HMODULE     modules[MAX_NUM_MODULES];
1445   static char filename[MAX_PATH];
1446   int         result = 0;
1447 
1448   int pid = os::current_process_id();
1449   hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
1450                          FALSE, pid);
1451   if (hProcess == NULL) return 0;
1452 
1453   DWORD size_needed;
1454   if (!EnumProcessModules(hProcess, modules, sizeof(modules), &size_needed)) {
1455     CloseHandle(hProcess);
1456     return 0;
1457   }
1458 
1459   // number of modules that are currently loaded
1460   int num_modules = size_needed / sizeof(HMODULE);
1461 
1462   for (int i = 0; i < MIN2(num_modules, MAX_NUM_MODULES); i++) {
1463     // Get Full pathname:
1464     if (!GetModuleFileNameEx(hProcess, modules[i], filename, sizeof(filename))) {
1465       filename[0] = '\0';
1466     }
1467 
1468     MODULEINFO modinfo;
1469     if (!GetModuleInformation(hProcess, modules[i], &modinfo, sizeof(modinfo))) {
1470       modinfo.lpBaseOfDll = NULL;
1471       modinfo.SizeOfImage = 0;
1472     }
1473 
1474     // Invoke callback function
1475     result = callback(filename, (address)modinfo.lpBaseOfDll,
1476                       (address)((u8)modinfo.lpBaseOfDll + (u8)modinfo.SizeOfImage), param);
1477     if (result) break;
1478   }
1479 
1480   CloseHandle(hProcess);
1481   return result;
1482 }
1483 
1484 bool os::get_host_name(char* buf, size_t buflen) {
1485   DWORD size = (DWORD)buflen;
1486   return (GetComputerNameEx(ComputerNameDnsHostname, buf, &size) == TRUE);
1487 }
1488 
1489 void os::get_summary_os_info(char* buf, size_t buflen) {
1490   stringStream sst(buf, buflen);
1491   os::win32::print_windows_version(&sst);
1492   // chop off newline character
1493   char* nl = strchr(buf, '\n');
1494   if (nl != NULL) *nl = '\0';
1495 }
1496 
1497 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
1498   int ret = vsnprintf(buf, len, fmt, args);
1499   // Get the correct buffer size if buf is too small
1500   if (ret < 0) {
1501     return _vscprintf(fmt, args);
1502   }
1503   return ret;
1504 }
1505 
1506 static inline time_t get_mtime(const char* filename) {
1507   struct stat st;
1508   int ret = os::stat(filename, &st);
1509   assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
1510   return st.st_mtime;
1511 }
1512 
1513 int os::compare_file_modified_times(const char* file1, const char* file2) {
1514   time_t t1 = get_mtime(file1);
1515   time_t t2 = get_mtime(file2);
1516   return t1 - t2;
1517 }
1518 
1519 void os::print_os_info_brief(outputStream* st) {
1520   os::print_os_info(st);
1521 }
1522 
1523 void os::print_os_info(outputStream* st) {
1524 #ifdef ASSERT
1525   char buffer[1024];
1526   st->print("HostName: ");
1527   if (get_host_name(buffer, sizeof(buffer))) {
1528     st->print("%s ", buffer);
1529   } else {
1530     st->print("N/A ");
1531   }
1532 #endif
1533   st->print("OS:");
1534   os::win32::print_windows_version(st);
1535 }
1536 
1537 void os::win32::print_windows_version(outputStream* st) {
1538   OSVERSIONINFOEX osvi;
1539   VS_FIXEDFILEINFO *file_info;
1540   TCHAR kernel32_path[MAX_PATH];
1541   UINT len, ret;
1542 
1543   // Use the GetVersionEx information to see if we're on a server or
1544   // workstation edition of Windows. Starting with Windows 8.1 we can't
1545   // trust the OS version information returned by this API.
1546   ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
1547   osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
1548   if (!GetVersionEx((OSVERSIONINFO *)&osvi)) {
1549     st->print_cr("Call to GetVersionEx failed");
1550     return;
1551   }
1552   bool is_workstation = (osvi.wProductType == VER_NT_WORKSTATION);
1553 
1554   // Get the full path to \Windows\System32\kernel32.dll and use that for
1555   // determining what version of Windows we're running on.
1556   len = MAX_PATH - (UINT)strlen("\\kernel32.dll") - 1;
1557   ret = GetSystemDirectory(kernel32_path, len);
1558   if (ret == 0 || ret > len) {
1559     st->print_cr("Call to GetSystemDirectory failed");
1560     return;
1561   }
1562   strncat(kernel32_path, "\\kernel32.dll", MAX_PATH - ret);
1563 
1564   DWORD version_size = GetFileVersionInfoSize(kernel32_path, NULL);
1565   if (version_size == 0) {
1566     st->print_cr("Call to GetFileVersionInfoSize failed");
1567     return;
1568   }
1569 
1570   LPTSTR version_info = (LPTSTR)os::malloc(version_size, mtInternal);
1571   if (version_info == NULL) {
1572     st->print_cr("Failed to allocate version_info");
1573     return;
1574   }
1575 
1576   if (!GetFileVersionInfo(kernel32_path, NULL, version_size, version_info)) {
1577     os::free(version_info);
1578     st->print_cr("Call to GetFileVersionInfo failed");
1579     return;
1580   }
1581 
1582   if (!VerQueryValue(version_info, TEXT("\\"), (LPVOID*)&file_info, &len)) {
1583     os::free(version_info);
1584     st->print_cr("Call to VerQueryValue failed");
1585     return;
1586   }
1587 
1588   int major_version = HIWORD(file_info->dwProductVersionMS);
1589   int minor_version = LOWORD(file_info->dwProductVersionMS);
1590   int build_number = HIWORD(file_info->dwProductVersionLS);
1591   int build_minor = LOWORD(file_info->dwProductVersionLS);
1592   int os_vers = major_version * 1000 + minor_version;
1593   os::free(version_info);
1594 
1595   st->print(" Windows ");
1596   switch (os_vers) {
1597 
1598   case 6000:
1599     if (is_workstation) {
1600       st->print("Vista");
1601     } else {
1602       st->print("Server 2008");
1603     }
1604     break;
1605 
1606   case 6001:
1607     if (is_workstation) {
1608       st->print("7");
1609     } else {
1610       st->print("Server 2008 R2");
1611     }
1612     break;
1613 
1614   case 6002:
1615     if (is_workstation) {
1616       st->print("8");
1617     } else {
1618       st->print("Server 2012");
1619     }
1620     break;
1621 
1622   case 6003:
1623     if (is_workstation) {
1624       st->print("8.1");
1625     } else {
1626       st->print("Server 2012 R2");
1627     }
1628     break;
1629 
1630   case 10000:
1631     if (is_workstation) {
1632       st->print("10");
1633     } else {
1634       st->print("Server 2016");
1635     }
1636     break;
1637 
1638   default:
1639     // Unrecognized windows, print out its major and minor versions
1640     st->print("%d.%d", major_version, minor_version);
1641     break;
1642   }
1643 
1644   // Retrieve SYSTEM_INFO from GetNativeSystemInfo call so that we could
1645   // find out whether we are running on 64 bit processor or not
1646   SYSTEM_INFO si;
1647   ZeroMemory(&si, sizeof(SYSTEM_INFO));
1648   GetNativeSystemInfo(&si);
1649   if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64) {
1650     st->print(" , 64 bit");
1651   }
1652 
1653   st->print(" Build %d", build_number);
1654   st->print(" (%d.%d.%d.%d)", major_version, minor_version, build_number, build_minor);
1655   st->cr();
1656 }
1657 
1658 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1659   // Nothing to do for now.
1660 }
1661 
1662 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1663   HKEY key;
1664   DWORD status = RegOpenKey(HKEY_LOCAL_MACHINE,
1665                "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", &key);
1666   if (status == ERROR_SUCCESS) {
1667     DWORD size = (DWORD)buflen;
1668     status = RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (byte*)buf, &size);
1669     if (status != ERROR_SUCCESS) {
1670         strncpy(buf, "## __CPU__", buflen);
1671     }
1672     RegCloseKey(key);
1673   } else {
1674     // Put generic cpu info to return
1675     strncpy(buf, "## __CPU__", buflen);
1676   }
1677 }
1678 
1679 void os::print_memory_info(outputStream* st) {
1680   st->print("Memory:");
1681   st->print(" %dk page", os::vm_page_size()>>10);
1682 
1683   // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
1684   // value if total memory is larger than 4GB
1685   MEMORYSTATUSEX ms;
1686   ms.dwLength = sizeof(ms);
1687   GlobalMemoryStatusEx(&ms);
1688 
1689   st->print(", physical %uk", os::physical_memory() >> 10);
1690   st->print("(%uk free)", os::available_memory() >> 10);
1691 
1692   st->print(", swap %uk", ms.ullTotalPageFile >> 10);
1693   st->print("(%uk free)", ms.ullAvailPageFile >> 10);
1694   st->cr();
1695 }
1696 
1697 void os::print_siginfo(outputStream *st, const void* siginfo) {
1698   const EXCEPTION_RECORD* const er = (EXCEPTION_RECORD*)siginfo;
1699   st->print("siginfo:");
1700 
1701   char tmp[64];
1702   if (os::exception_name(er->ExceptionCode, tmp, sizeof(tmp)) == NULL) {
1703     strcpy(tmp, "EXCEPTION_??");
1704   }
1705   st->print(" %s (0x%x)", tmp, er->ExceptionCode);
1706 
1707   if ((er->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
1708        er->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) &&
1709        er->NumberParameters >= 2) {
1710     switch (er->ExceptionInformation[0]) {
1711     case 0: st->print(", reading address"); break;
1712     case 1: st->print(", writing address"); break;
1713     case 8: st->print(", data execution prevention violation at address"); break;
1714     default: st->print(", ExceptionInformation=" INTPTR_FORMAT,
1715                        er->ExceptionInformation[0]);
1716     }
1717     st->print(" " INTPTR_FORMAT, er->ExceptionInformation[1]);
1718   } else {
1719     int num = er->NumberParameters;
1720     if (num > 0) {
1721       st->print(", ExceptionInformation=");
1722       for (int i = 0; i < num; i++) {
1723         st->print(INTPTR_FORMAT " ", er->ExceptionInformation[i]);
1724       }
1725     }
1726   }
1727   st->cr();
1728 }
1729 
1730 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1731   // do nothing
1732 }
1733 
1734 static char saved_jvm_path[MAX_PATH] = {0};
1735 
1736 // Find the full path to the current module, jvm.dll
1737 void os::jvm_path(char *buf, jint buflen) {
1738   // Error checking.
1739   if (buflen < MAX_PATH) {
1740     assert(false, "must use a large-enough buffer");
1741     buf[0] = '\0';
1742     return;
1743   }
1744   // Lazy resolve the path to current module.
1745   if (saved_jvm_path[0] != 0) {
1746     strcpy(buf, saved_jvm_path);
1747     return;
1748   }
1749 
1750   buf[0] = '\0';
1751   if (Arguments::sun_java_launcher_is_altjvm()) {
1752     // Support for the java launcher's '-XXaltjvm=<path>' option. Check
1753     // for a JAVA_HOME environment variable and fix up the path so it
1754     // looks like jvm.dll is installed there (append a fake suffix
1755     // hotspot/jvm.dll).
1756     char* java_home_var = ::getenv("JAVA_HOME");
1757     if (java_home_var != NULL && java_home_var[0] != 0 &&
1758         strlen(java_home_var) < (size_t)buflen) {
1759       strncpy(buf, java_home_var, buflen);
1760 
1761       // determine if this is a legacy image or modules image
1762       // modules image doesn't have "jre" subdirectory
1763       size_t len = strlen(buf);
1764       char* jrebin_p = buf + len;
1765       jio_snprintf(jrebin_p, buflen-len, "\\jre\\bin\\");
1766       if (0 != _access(buf, 0)) {
1767         jio_snprintf(jrebin_p, buflen-len, "\\bin\\");
1768       }
1769       len = strlen(buf);
1770       jio_snprintf(buf + len, buflen-len, "hotspot\\jvm.dll");
1771     }
1772   }
1773 
1774   if (buf[0] == '\0') {
1775     GetModuleFileName(vm_lib_handle, buf, buflen);
1776   }
1777   strncpy(saved_jvm_path, buf, MAX_PATH);
1778   saved_jvm_path[MAX_PATH - 1] = '\0';
1779 }
1780 
1781 
1782 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1783 #ifndef _WIN64
1784   st->print("_");
1785 #endif
1786 }
1787 
1788 
1789 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1790 #ifndef _WIN64
1791   st->print("@%d", args_size  * sizeof(int));
1792 #endif
1793 }
1794 
1795 // This method is a copy of JDK's sysGetLastErrorString
1796 // from src/windows/hpi/src/system_md.c
1797 
1798 size_t os::lasterror(char* buf, size_t len) {
1799   DWORD errval;
1800 
1801   if ((errval = GetLastError()) != 0) {
1802     // DOS error
1803     size_t n = (size_t)FormatMessage(
1804                                      FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
1805                                      NULL,
1806                                      errval,
1807                                      0,
1808                                      buf,
1809                                      (DWORD)len,
1810                                      NULL);
1811     if (n > 3) {
1812       // Drop final '.', CR, LF
1813       if (buf[n - 1] == '\n') n--;
1814       if (buf[n - 1] == '\r') n--;
1815       if (buf[n - 1] == '.') n--;
1816       buf[n] = '\0';
1817     }
1818     return n;
1819   }
1820 
1821   if (errno != 0) {
1822     // C runtime error that has no corresponding DOS error code
1823     const char* s = os::strerror(errno);
1824     size_t n = strlen(s);
1825     if (n >= len) n = len - 1;
1826     strncpy(buf, s, n);
1827     buf[n] = '\0';
1828     return n;
1829   }
1830 
1831   return 0;
1832 }
1833 
1834 int os::get_last_error() {
1835   DWORD error = GetLastError();
1836   if (error == 0) {
1837     error = errno;
1838   }
1839   return (int)error;
1840 }
1841 
1842 WindowsSemaphore::WindowsSemaphore(uint value) {
1843   _semaphore = ::CreateSemaphore(NULL, value, LONG_MAX, NULL);
1844 
1845   guarantee(_semaphore != NULL, "CreateSemaphore failed with error code: %lu", GetLastError());
1846 }
1847 
1848 WindowsSemaphore::~WindowsSemaphore() {
1849   ::CloseHandle(_semaphore);
1850 }
1851 
1852 void WindowsSemaphore::signal(uint count) {
1853   if (count > 0) {
1854     BOOL ret = ::ReleaseSemaphore(_semaphore, count, NULL);
1855 
1856     assert(ret != 0, "ReleaseSemaphore failed with error code: %lu", GetLastError());
1857   }
1858 }
1859 
1860 void WindowsSemaphore::wait() {
1861   DWORD ret = ::WaitForSingleObject(_semaphore, INFINITE);
1862   assert(ret != WAIT_FAILED,   "WaitForSingleObject failed with error code: %lu", GetLastError());
1863   assert(ret == WAIT_OBJECT_0, "WaitForSingleObject failed with return value: %lu", ret);
1864 }
1865 
1866 bool WindowsSemaphore::trywait() {
1867   DWORD ret = ::WaitForSingleObject(_semaphore, 0);
1868   assert(ret != WAIT_FAILED,   "WaitForSingleObject failed with error code: %lu", GetLastError());
1869   return ret == WAIT_OBJECT_0;
1870 }
1871 
1872 // sun.misc.Signal
1873 // NOTE that this is a workaround for an apparent kernel bug where if
1874 // a signal handler for SIGBREAK is installed then that signal handler
1875 // takes priority over the console control handler for CTRL_CLOSE_EVENT.
1876 // See bug 4416763.
1877 static void (*sigbreakHandler)(int) = NULL;
1878 
1879 static void UserHandler(int sig, void *siginfo, void *context) {
1880   os::signal_notify(sig);
1881   // We need to reinstate the signal handler each time...
1882   os::signal(sig, (void*)UserHandler);
1883 }
1884 
1885 void* os::user_handler() {
1886   return (void*) UserHandler;
1887 }
1888 
1889 void* os::signal(int signal_number, void* handler) {
1890   if ((signal_number == SIGBREAK) && (!ReduceSignalUsage)) {
1891     void (*oldHandler)(int) = sigbreakHandler;
1892     sigbreakHandler = (void (*)(int)) handler;
1893     return (void*) oldHandler;
1894   } else {
1895     return (void*)::signal(signal_number, (void (*)(int))handler);
1896   }
1897 }
1898 
1899 void os::signal_raise(int signal_number) {
1900   raise(signal_number);
1901 }
1902 
1903 // The Win32 C runtime library maps all console control events other than ^C
1904 // into SIGBREAK, which makes it impossible to distinguish ^BREAK from close,
1905 // logoff, and shutdown events.  We therefore install our own console handler
1906 // that raises SIGTERM for the latter cases.
1907 //
1908 static BOOL WINAPI consoleHandler(DWORD event) {
1909   switch (event) {
1910   case CTRL_C_EVENT:
1911     if (VMError::is_error_reported()) {
1912       // Ctrl-C is pressed during error reporting, likely because the error
1913       // handler fails to abort. Let VM die immediately.
1914       os::die();
1915     }
1916 
1917     os::signal_raise(SIGINT);
1918     return TRUE;
1919     break;
1920   case CTRL_BREAK_EVENT:
1921     if (sigbreakHandler != NULL) {
1922       (*sigbreakHandler)(SIGBREAK);
1923     }
1924     return TRUE;
1925     break;
1926   case CTRL_LOGOFF_EVENT: {
1927     // Don't terminate JVM if it is running in a non-interactive session,
1928     // such as a service process.
1929     USEROBJECTFLAGS flags;
1930     HANDLE handle = GetProcessWindowStation();
1931     if (handle != NULL &&
1932         GetUserObjectInformation(handle, UOI_FLAGS, &flags,
1933         sizeof(USEROBJECTFLAGS), NULL)) {
1934       // If it is a non-interactive session, let next handler to deal
1935       // with it.
1936       if ((flags.dwFlags & WSF_VISIBLE) == 0) {
1937         return FALSE;
1938       }
1939     }
1940   }
1941   case CTRL_CLOSE_EVENT:
1942   case CTRL_SHUTDOWN_EVENT:
1943     os::signal_raise(SIGTERM);
1944     return TRUE;
1945     break;
1946   default:
1947     break;
1948   }
1949   return FALSE;
1950 }
1951 
1952 // The following code is moved from os.cpp for making this
1953 // code platform specific, which it is by its very nature.
1954 
1955 // Return maximum OS signal used + 1 for internal use only
1956 // Used as exit signal for signal_thread
1957 int os::sigexitnum_pd() {
1958   return NSIG;
1959 }
1960 
1961 // a counter for each possible signal value, including signal_thread exit signal
1962 static volatile jint pending_signals[NSIG+1] = { 0 };
1963 static HANDLE sig_sem = NULL;
1964 
1965 void os::signal_init_pd() {
1966   // Initialize signal structures
1967   memset((void*)pending_signals, 0, sizeof(pending_signals));
1968 
1969   sig_sem = ::CreateSemaphore(NULL, 0, NSIG+1, NULL);
1970 
1971   // Programs embedding the VM do not want it to attempt to receive
1972   // events like CTRL_LOGOFF_EVENT, which are used to implement the
1973   // shutdown hooks mechanism introduced in 1.3.  For example, when
1974   // the VM is run as part of a Windows NT service (i.e., a servlet
1975   // engine in a web server), the correct behavior is for any console
1976   // control handler to return FALSE, not TRUE, because the OS's
1977   // "final" handler for such events allows the process to continue if
1978   // it is a service (while terminating it if it is not a service).
1979   // To make this behavior uniform and the mechanism simpler, we
1980   // completely disable the VM's usage of these console events if -Xrs
1981   // (=ReduceSignalUsage) is specified.  This means, for example, that
1982   // the CTRL-BREAK thread dump mechanism is also disabled in this
1983   // case.  See bugs 4323062, 4345157, and related bugs.
1984 
1985   if (!ReduceSignalUsage) {
1986     // Add a CTRL-C handler
1987     SetConsoleCtrlHandler(consoleHandler, TRUE);
1988   }
1989 }
1990 
1991 void os::signal_notify(int signal_number) {
1992   BOOL ret;
1993   if (sig_sem != NULL) {
1994     Atomic::inc(&pending_signals[signal_number]);
1995     ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
1996     assert(ret != 0, "ReleaseSemaphore() failed");
1997   }
1998 }
1999 
2000 static int check_pending_signals(bool wait_for_signal) {
2001   DWORD ret;
2002   while (true) {
2003     for (int i = 0; i < NSIG + 1; i++) {
2004       jint n = pending_signals[i];
2005       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2006         return i;
2007       }
2008     }
2009     if (!wait_for_signal) {
2010       return -1;
2011     }
2012 
2013     JavaThread *thread = JavaThread::current();
2014 
2015     ThreadBlockInVM tbivm(thread);
2016 
2017     bool threadIsSuspended;
2018     do {
2019       thread->set_suspend_equivalent();
2020       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2021       ret = ::WaitForSingleObject(sig_sem, INFINITE);
2022       assert(ret == WAIT_OBJECT_0, "WaitForSingleObject() failed");
2023 
2024       // were we externally suspended while we were waiting?
2025       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2026       if (threadIsSuspended) {
2027         // The semaphore has been incremented, but while we were waiting
2028         // another thread suspended us. We don't want to continue running
2029         // while suspended because that would surprise the thread that
2030         // suspended us.
2031         ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
2032         assert(ret != 0, "ReleaseSemaphore() failed");
2033 
2034         thread->java_suspend_self();
2035       }
2036     } while (threadIsSuspended);
2037   }
2038 }
2039 
2040 int os::signal_lookup() {
2041   return check_pending_signals(false);
2042 }
2043 
2044 int os::signal_wait() {
2045   return check_pending_signals(true);
2046 }
2047 
2048 // Implicit OS exception handling
2049 
2050 LONG Handle_Exception(struct _EXCEPTION_POINTERS* exceptionInfo,
2051                       address handler) {
2052   JavaThread* thread = (JavaThread*) Thread::current_or_null();
2053   // Save pc in thread
2054 #ifdef _M_AMD64
2055   // Do not blow up if no thread info available.
2056   if (thread) {
2057     thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Rip);
2058   }
2059   // Set pc to handler
2060   exceptionInfo->ContextRecord->Rip = (DWORD64)handler;
2061 #else
2062   // Do not blow up if no thread info available.
2063   if (thread) {
2064     thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Eip);
2065   }
2066   // Set pc to handler
2067   exceptionInfo->ContextRecord->Eip = (DWORD)(DWORD_PTR)handler;
2068 #endif
2069 
2070   // Continue the execution
2071   return EXCEPTION_CONTINUE_EXECUTION;
2072 }
2073 
2074 
2075 // Used for PostMortemDump
2076 extern "C" void safepoints();
2077 extern "C" void find(int x);
2078 extern "C" void events();
2079 
2080 // According to Windows API documentation, an illegal instruction sequence should generate
2081 // the 0xC000001C exception code. However, real world experience shows that occasionnaly
2082 // the execution of an illegal instruction can generate the exception code 0xC000001E. This
2083 // seems to be an undocumented feature of Win NT 4.0 (and probably other Windows systems).
2084 
2085 #define EXCEPTION_ILLEGAL_INSTRUCTION_2 0xC000001E
2086 
2087 // From "Execution Protection in the Windows Operating System" draft 0.35
2088 // Once a system header becomes available, the "real" define should be
2089 // included or copied here.
2090 #define EXCEPTION_INFO_EXEC_VIOLATION 0x08
2091 
2092 // Windows Vista/2008 heap corruption check
2093 #define EXCEPTION_HEAP_CORRUPTION        0xC0000374
2094 
2095 // All Visual C++ exceptions thrown from code generated by the Microsoft Visual
2096 // C++ compiler contain this error code. Because this is a compiler-generated
2097 // error, the code is not listed in the Win32 API header files.
2098 // The code is actually a cryptic mnemonic device, with the initial "E"
2099 // standing for "exception" and the final 3 bytes (0x6D7363) representing the
2100 // ASCII values of "msc".
2101 
2102 #define EXCEPTION_UNCAUGHT_CXX_EXCEPTION    0xE06D7363
2103 
2104 #define def_excpt(val) { #val, (val) }
2105 
2106 static const struct { char* name; uint number; } exceptlabels[] = {
2107     def_excpt(EXCEPTION_ACCESS_VIOLATION),
2108     def_excpt(EXCEPTION_DATATYPE_MISALIGNMENT),
2109     def_excpt(EXCEPTION_BREAKPOINT),
2110     def_excpt(EXCEPTION_SINGLE_STEP),
2111     def_excpt(EXCEPTION_ARRAY_BOUNDS_EXCEEDED),
2112     def_excpt(EXCEPTION_FLT_DENORMAL_OPERAND),
2113     def_excpt(EXCEPTION_FLT_DIVIDE_BY_ZERO),
2114     def_excpt(EXCEPTION_FLT_INEXACT_RESULT),
2115     def_excpt(EXCEPTION_FLT_INVALID_OPERATION),
2116     def_excpt(EXCEPTION_FLT_OVERFLOW),
2117     def_excpt(EXCEPTION_FLT_STACK_CHECK),
2118     def_excpt(EXCEPTION_FLT_UNDERFLOW),
2119     def_excpt(EXCEPTION_INT_DIVIDE_BY_ZERO),
2120     def_excpt(EXCEPTION_INT_OVERFLOW),
2121     def_excpt(EXCEPTION_PRIV_INSTRUCTION),
2122     def_excpt(EXCEPTION_IN_PAGE_ERROR),
2123     def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION),
2124     def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION_2),
2125     def_excpt(EXCEPTION_NONCONTINUABLE_EXCEPTION),
2126     def_excpt(EXCEPTION_STACK_OVERFLOW),
2127     def_excpt(EXCEPTION_INVALID_DISPOSITION),
2128     def_excpt(EXCEPTION_GUARD_PAGE),
2129     def_excpt(EXCEPTION_INVALID_HANDLE),
2130     def_excpt(EXCEPTION_UNCAUGHT_CXX_EXCEPTION),
2131     def_excpt(EXCEPTION_HEAP_CORRUPTION)
2132 };
2133 
2134 #undef def_excpt
2135 
2136 const char* os::exception_name(int exception_code, char *buf, size_t size) {
2137   uint code = static_cast<uint>(exception_code);
2138   for (uint i = 0; i < ARRAY_SIZE(exceptlabels); ++i) {
2139     if (exceptlabels[i].number == code) {
2140       jio_snprintf(buf, size, "%s", exceptlabels[i].name);
2141       return buf;
2142     }
2143   }
2144 
2145   return NULL;
2146 }
2147 
2148 //-----------------------------------------------------------------------------
2149 LONG Handle_IDiv_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2150   // handle exception caused by idiv; should only happen for -MinInt/-1
2151   // (division by zero is handled explicitly)
2152 #ifdef  _M_AMD64
2153   PCONTEXT ctx = exceptionInfo->ContextRecord;
2154   address pc = (address)ctx->Rip;
2155   assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && pc[1] == 0xF7 || pc[0] == 0xF7, "not an idiv opcode");
2156   assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && (pc[2] & ~0x7) == 0xF8 || (pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2157   if (pc[0] == 0xF7) {
2158     // set correct result values and continue after idiv instruction
2159     ctx->Rip = (DWORD64)pc + 2;        // idiv reg, reg  is 2 bytes
2160   } else {
2161     ctx->Rip = (DWORD64)pc + 3;        // REX idiv reg, reg  is 3 bytes
2162   }
2163   // Do not set ctx->Rax as it already contains the correct value (either 32 or 64 bit, depending on the operation)
2164   // this is the case because the exception only happens for -MinValue/-1 and -MinValue is always in rax because of the
2165   // idiv opcode (0xF7).
2166   ctx->Rdx = (DWORD)0;             // remainder
2167   // Continue the execution
2168 #else
2169   PCONTEXT ctx = exceptionInfo->ContextRecord;
2170   address pc = (address)ctx->Eip;
2171   assert(pc[0] == 0xF7, "not an idiv opcode");
2172   assert((pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2173   assert(ctx->Eax == min_jint, "unexpected idiv exception");
2174   // set correct result values and continue after idiv instruction
2175   ctx->Eip = (DWORD)pc + 2;        // idiv reg, reg  is 2 bytes
2176   ctx->Eax = (DWORD)min_jint;      // result
2177   ctx->Edx = (DWORD)0;             // remainder
2178   // Continue the execution
2179 #endif
2180   return EXCEPTION_CONTINUE_EXECUTION;
2181 }
2182 
2183 //-----------------------------------------------------------------------------
2184 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2185   PCONTEXT ctx = exceptionInfo->ContextRecord;
2186 #ifndef  _WIN64
2187   // handle exception caused by native method modifying control word
2188   DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2189 
2190   switch (exception_code) {
2191   case EXCEPTION_FLT_DENORMAL_OPERAND:
2192   case EXCEPTION_FLT_DIVIDE_BY_ZERO:
2193   case EXCEPTION_FLT_INEXACT_RESULT:
2194   case EXCEPTION_FLT_INVALID_OPERATION:
2195   case EXCEPTION_FLT_OVERFLOW:
2196   case EXCEPTION_FLT_STACK_CHECK:
2197   case EXCEPTION_FLT_UNDERFLOW:
2198     jint fp_control_word = (* (jint*) StubRoutines::addr_fpu_cntrl_wrd_std());
2199     if (fp_control_word != ctx->FloatSave.ControlWord) {
2200       // Restore FPCW and mask out FLT exceptions
2201       ctx->FloatSave.ControlWord = fp_control_word | 0xffffffc0;
2202       // Mask out pending FLT exceptions
2203       ctx->FloatSave.StatusWord &=  0xffffff00;
2204       return EXCEPTION_CONTINUE_EXECUTION;
2205     }
2206   }
2207 
2208   if (prev_uef_handler != NULL) {
2209     // We didn't handle this exception so pass it to the previous
2210     // UnhandledExceptionFilter.
2211     return (prev_uef_handler)(exceptionInfo);
2212   }
2213 #else // !_WIN64
2214   // On Windows, the mxcsr control bits are non-volatile across calls
2215   // See also CR 6192333
2216   //
2217   jint MxCsr = INITIAL_MXCSR;
2218   // we can't use StubRoutines::addr_mxcsr_std()
2219   // because in Win64 mxcsr is not saved there
2220   if (MxCsr != ctx->MxCsr) {
2221     ctx->MxCsr = MxCsr;
2222     return EXCEPTION_CONTINUE_EXECUTION;
2223   }
2224 #endif // !_WIN64
2225 
2226   return EXCEPTION_CONTINUE_SEARCH;
2227 }
2228 
2229 static inline void report_error(Thread* t, DWORD exception_code,
2230                                 address addr, void* siginfo, void* context) {
2231   VMError::report_and_die(t, exception_code, addr, siginfo, context);
2232 
2233   // If UseOsErrorReporting, this will return here and save the error file
2234   // somewhere where we can find it in the minidump.
2235 }
2236 
2237 bool os::win32::get_frame_at_stack_banging_point(JavaThread* thread,
2238         struct _EXCEPTION_POINTERS* exceptionInfo, address pc, frame* fr) {
2239   PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2240   address addr = (address) exceptionRecord->ExceptionInformation[1];
2241   if (Interpreter::contains(pc)) {
2242     *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2243     if (!fr->is_first_java_frame()) {
2244       // get_frame_at_stack_banging_point() is only called when we
2245       // have well defined stacks so java_sender() calls do not need
2246       // to assert safe_for_sender() first.
2247       *fr = fr->java_sender();
2248     }
2249   } else {
2250     // more complex code with compiled code
2251     assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
2252     CodeBlob* cb = CodeCache::find_blob(pc);
2253     if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
2254       // Not sure where the pc points to, fallback to default
2255       // stack overflow handling
2256       return false;
2257     } else {
2258       *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2259       // in compiled code, the stack banging is performed just after the return pc
2260       // has been pushed on the stack
2261       *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));
2262       if (!fr->is_java_frame()) {
2263         // See java_sender() comment above.
2264         *fr = fr->java_sender();
2265       }
2266     }
2267   }
2268   assert(fr->is_java_frame(), "Safety check");
2269   return true;
2270 }
2271 
2272 //-----------------------------------------------------------------------------
2273 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2274   if (InterceptOSException) return EXCEPTION_CONTINUE_SEARCH;
2275   DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2276 #ifdef _M_AMD64
2277   address pc = (address) exceptionInfo->ContextRecord->Rip;
2278 #else
2279   address pc = (address) exceptionInfo->ContextRecord->Eip;
2280 #endif
2281   Thread* t = Thread::current_or_null_safe();
2282 
2283   // Handle SafeFetch32 and SafeFetchN exceptions.
2284   if (StubRoutines::is_safefetch_fault(pc)) {
2285     return Handle_Exception(exceptionInfo, StubRoutines::continuation_for_safefetch_fault(pc));
2286   }
2287 
2288 #ifndef _WIN64
2289   // Execution protection violation - win32 running on AMD64 only
2290   // Handled first to avoid misdiagnosis as a "normal" access violation;
2291   // This is safe to do because we have a new/unique ExceptionInformation
2292   // code for this condition.
2293   if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2294     PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2295     int exception_subcode = (int) exceptionRecord->ExceptionInformation[0];
2296     address addr = (address) exceptionRecord->ExceptionInformation[1];
2297 
2298     if (exception_subcode == EXCEPTION_INFO_EXEC_VIOLATION) {
2299       int page_size = os::vm_page_size();
2300 
2301       // Make sure the pc and the faulting address are sane.
2302       //
2303       // If an instruction spans a page boundary, and the page containing
2304       // the beginning of the instruction is executable but the following
2305       // page is not, the pc and the faulting address might be slightly
2306       // different - we still want to unguard the 2nd page in this case.
2307       //
2308       // 15 bytes seems to be a (very) safe value for max instruction size.
2309       bool pc_is_near_addr =
2310         (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
2311       bool instr_spans_page_boundary =
2312         (align_down((intptr_t) pc ^ (intptr_t) addr,
2313                          (intptr_t) page_size) > 0);
2314 
2315       if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
2316         static volatile address last_addr =
2317           (address) os::non_memory_address_word();
2318 
2319         // In conservative mode, don't unguard unless the address is in the VM
2320         if (UnguardOnExecutionViolation > 0 && addr != last_addr &&
2321             (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
2322 
2323           // Set memory to RWX and retry
2324           address page_start = align_down(addr, page_size);
2325           bool res = os::protect_memory((char*) page_start, page_size,
2326                                         os::MEM_PROT_RWX);
2327 
2328           log_debug(os)("Execution protection violation "
2329                         "at " INTPTR_FORMAT
2330                         ", unguarding " INTPTR_FORMAT ": %s", p2i(addr),
2331                         p2i(page_start), (res ? "success" : os::strerror(errno)));
2332 
2333           // Set last_addr so if we fault again at the same address, we don't
2334           // end up in an endless loop.
2335           //
2336           // There are two potential complications here.  Two threads trapping
2337           // at the same address at the same time could cause one of the
2338           // threads to think it already unguarded, and abort the VM.  Likely
2339           // very rare.
2340           //
2341           // The other race involves two threads alternately trapping at
2342           // different addresses and failing to unguard the page, resulting in
2343           // an endless loop.  This condition is probably even more unlikely
2344           // than the first.
2345           //
2346           // Although both cases could be avoided by using locks or thread
2347           // local last_addr, these solutions are unnecessary complication:
2348           // this handler is a best-effort safety net, not a complete solution.
2349           // It is disabled by default and should only be used as a workaround
2350           // in case we missed any no-execute-unsafe VM code.
2351 
2352           last_addr = addr;
2353 
2354           return EXCEPTION_CONTINUE_EXECUTION;
2355         }
2356       }
2357 
2358       // Last unguard failed or not unguarding
2359       tty->print_raw_cr("Execution protection violation");
2360       report_error(t, exception_code, addr, exceptionInfo->ExceptionRecord,
2361                    exceptionInfo->ContextRecord);
2362       return EXCEPTION_CONTINUE_SEARCH;
2363     }
2364   }
2365 #endif // _WIN64
2366 
2367   // Check to see if we caught the safepoint code in the
2368   // process of write protecting the memory serialization page.
2369   // It write enables the page immediately after protecting it
2370   // so just return.
2371   if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2372     if (t != NULL && t->is_Java_thread()) {
2373       JavaThread* thread = (JavaThread*) t;
2374       PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2375       address addr = (address) exceptionRecord->ExceptionInformation[1];
2376       if (os::is_memory_serialize_page(thread, addr)) {
2377         // Block current thread until the memory serialize page permission restored.
2378         os::block_on_serialize_page_trap();
2379         return EXCEPTION_CONTINUE_EXECUTION;
2380       }
2381     }
2382   }
2383 
2384   if ((exception_code == EXCEPTION_ACCESS_VIOLATION) &&
2385       VM_Version::is_cpuinfo_segv_addr(pc)) {
2386     // Verify that OS save/restore AVX registers.
2387     return Handle_Exception(exceptionInfo, VM_Version::cpuinfo_cont_addr());
2388   }
2389 
2390   if (t != NULL && t->is_Java_thread()) {
2391     JavaThread* thread = (JavaThread*) t;
2392     bool in_java = thread->thread_state() == _thread_in_Java;
2393 
2394     // Handle potential stack overflows up front.
2395     if (exception_code == EXCEPTION_STACK_OVERFLOW) {
2396       if (thread->stack_guards_enabled()) {
2397         if (in_java) {
2398           frame fr;
2399           PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2400           address addr = (address) exceptionRecord->ExceptionInformation[1];
2401           if (os::win32::get_frame_at_stack_banging_point(thread, exceptionInfo, pc, &fr)) {
2402             assert(fr.is_java_frame(), "Must be a Java frame");
2403             SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
2404           }
2405         }
2406         // Yellow zone violation.  The o/s has unprotected the first yellow
2407         // zone page for us.  Note:  must call disable_stack_yellow_zone to
2408         // update the enabled status, even if the zone contains only one page.
2409         assert(thread->thread_state() != _thread_in_vm, "Undersized StackShadowPages");
2410         thread->disable_stack_yellow_reserved_zone();
2411         // If not in java code, return and hope for the best.
2412         return in_java
2413             ? Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW))
2414             :  EXCEPTION_CONTINUE_EXECUTION;
2415       } else {
2416         // Fatal red zone violation.
2417         thread->disable_stack_red_zone();
2418         tty->print_raw_cr("An unrecoverable stack overflow has occurred.");
2419         report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2420                       exceptionInfo->ContextRecord);
2421         return EXCEPTION_CONTINUE_SEARCH;
2422       }
2423     } else if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2424       // Either stack overflow or null pointer exception.
2425       if (in_java) {
2426         PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2427         address addr = (address) exceptionRecord->ExceptionInformation[1];
2428         address stack_end = thread->stack_end();
2429         if (addr < stack_end && addr >= stack_end - os::vm_page_size()) {
2430           // Stack overflow.
2431           assert(!os::uses_stack_guard_pages(),
2432                  "should be caught by red zone code above.");
2433           return Handle_Exception(exceptionInfo,
2434                                   SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW));
2435         }
2436         // Check for safepoint polling and implicit null
2437         // We only expect null pointers in the stubs (vtable)
2438         // the rest are checked explicitly now.
2439         CodeBlob* cb = CodeCache::find_blob(pc);
2440         if (cb != NULL) {
2441           if (os::is_poll_address(addr)) {
2442             address stub = SharedRuntime::get_poll_stub(pc);
2443             return Handle_Exception(exceptionInfo, stub);
2444           }
2445         }
2446         {
2447 #ifdef _WIN64
2448           // If it's a legal stack address map the entire region in
2449           //
2450           PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2451           address addr = (address) exceptionRecord->ExceptionInformation[1];
2452           if (addr > thread->stack_reserved_zone_base() && addr < thread->stack_base()) {
2453             addr = (address)((uintptr_t)addr &
2454                              (~((uintptr_t)os::vm_page_size() - (uintptr_t)1)));
2455             os::commit_memory((char *)addr, thread->stack_base() - addr,
2456                               !ExecMem);
2457             return EXCEPTION_CONTINUE_EXECUTION;
2458           } else
2459 #endif
2460           {
2461             // Null pointer exception.
2462             if (!MacroAssembler::needs_explicit_null_check((intptr_t)addr)) {
2463               address stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
2464               if (stub != NULL) return Handle_Exception(exceptionInfo, stub);
2465             }
2466             report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2467                          exceptionInfo->ContextRecord);
2468             return EXCEPTION_CONTINUE_SEARCH;
2469           }
2470         }
2471       }
2472 
2473 #ifdef _WIN64
2474       // Special care for fast JNI field accessors.
2475       // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks
2476       // in and the heap gets shrunk before the field access.
2477       if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2478         address addr = JNI_FastGetField::find_slowcase_pc(pc);
2479         if (addr != (address)-1) {
2480           return Handle_Exception(exceptionInfo, addr);
2481         }
2482       }
2483 #endif
2484 
2485       // Stack overflow or null pointer exception in native code.
2486       report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2487                    exceptionInfo->ContextRecord);
2488       return EXCEPTION_CONTINUE_SEARCH;
2489     } // /EXCEPTION_ACCESS_VIOLATION
2490     // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2491 
2492     if (in_java) {
2493       switch (exception_code) {
2494       case EXCEPTION_INT_DIVIDE_BY_ZERO:
2495         return Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO));
2496 
2497       case EXCEPTION_INT_OVERFLOW:
2498         return Handle_IDiv_Exception(exceptionInfo);
2499 
2500       } // switch
2501     }
2502     if (((thread->thread_state() == _thread_in_Java) ||
2503          (thread->thread_state() == _thread_in_native)) &&
2504          exception_code != EXCEPTION_UNCAUGHT_CXX_EXCEPTION) {
2505       LONG result=Handle_FLT_Exception(exceptionInfo);
2506       if (result==EXCEPTION_CONTINUE_EXECUTION) return result;
2507     }
2508   }
2509 
2510   if (exception_code != EXCEPTION_BREAKPOINT) {
2511     report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2512                  exceptionInfo->ContextRecord);
2513   }
2514   return EXCEPTION_CONTINUE_SEARCH;
2515 }
2516 
2517 #ifndef _WIN64
2518 // Special care for fast JNI accessors.
2519 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in and
2520 // the heap gets shrunk before the field access.
2521 // Need to install our own structured exception handler since native code may
2522 // install its own.
2523 LONG WINAPI fastJNIAccessorExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2524   DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2525   if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2526     address pc = (address) exceptionInfo->ContextRecord->Eip;
2527     address addr = JNI_FastGetField::find_slowcase_pc(pc);
2528     if (addr != (address)-1) {
2529       return Handle_Exception(exceptionInfo, addr);
2530     }
2531   }
2532   return EXCEPTION_CONTINUE_SEARCH;
2533 }
2534 
2535 #define DEFINE_FAST_GETFIELD(Return, Fieldname, Result)                     \
2536   Return JNICALL jni_fast_Get##Result##Field_wrapper(JNIEnv *env,           \
2537                                                      jobject obj,           \
2538                                                      jfieldID fieldID) {    \
2539     __try {                                                                 \
2540       return (*JNI_FastGetField::jni_fast_Get##Result##Field_fp)(env,       \
2541                                                                  obj,       \
2542                                                                  fieldID);  \
2543     } __except(fastJNIAccessorExceptionFilter((_EXCEPTION_POINTERS*)        \
2544                                               _exception_info())) {         \
2545     }                                                                       \
2546     return 0;                                                               \
2547   }
2548 
2549 DEFINE_FAST_GETFIELD(jboolean, bool,   Boolean)
2550 DEFINE_FAST_GETFIELD(jbyte,    byte,   Byte)
2551 DEFINE_FAST_GETFIELD(jchar,    char,   Char)
2552 DEFINE_FAST_GETFIELD(jshort,   short,  Short)
2553 DEFINE_FAST_GETFIELD(jint,     int,    Int)
2554 DEFINE_FAST_GETFIELD(jlong,    long,   Long)
2555 DEFINE_FAST_GETFIELD(jfloat,   float,  Float)
2556 DEFINE_FAST_GETFIELD(jdouble,  double, Double)
2557 
2558 address os::win32::fast_jni_accessor_wrapper(BasicType type) {
2559   switch (type) {
2560   case T_BOOLEAN: return (address)jni_fast_GetBooleanField_wrapper;
2561   case T_BYTE:    return (address)jni_fast_GetByteField_wrapper;
2562   case T_CHAR:    return (address)jni_fast_GetCharField_wrapper;
2563   case T_SHORT:   return (address)jni_fast_GetShortField_wrapper;
2564   case T_INT:     return (address)jni_fast_GetIntField_wrapper;
2565   case T_LONG:    return (address)jni_fast_GetLongField_wrapper;
2566   case T_FLOAT:   return (address)jni_fast_GetFloatField_wrapper;
2567   case T_DOUBLE:  return (address)jni_fast_GetDoubleField_wrapper;
2568   default:        ShouldNotReachHere();
2569   }
2570   return (address)-1;
2571 }
2572 #endif
2573 
2574 // Virtual Memory
2575 
2576 int os::vm_page_size() { return os::win32::vm_page_size(); }
2577 int os::vm_allocation_granularity() {
2578   return os::win32::vm_allocation_granularity();
2579 }
2580 
2581 // Windows large page support is available on Windows 2003. In order to use
2582 // large page memory, the administrator must first assign additional privilege
2583 // to the user:
2584 //   + select Control Panel -> Administrative Tools -> Local Security Policy
2585 //   + select Local Policies -> User Rights Assignment
2586 //   + double click "Lock pages in memory", add users and/or groups
2587 //   + reboot
2588 // Note the above steps are needed for administrator as well, as administrators
2589 // by default do not have the privilege to lock pages in memory.
2590 //
2591 // Note about Windows 2003: although the API supports committing large page
2592 // memory on a page-by-page basis and VirtualAlloc() returns success under this
2593 // scenario, I found through experiment it only uses large page if the entire
2594 // memory region is reserved and committed in a single VirtualAlloc() call.
2595 // This makes Windows large page support more or less like Solaris ISM, in
2596 // that the entire heap must be committed upfront. This probably will change
2597 // in the future, if so the code below needs to be revisited.
2598 
2599 #ifndef MEM_LARGE_PAGES
2600   #define MEM_LARGE_PAGES 0x20000000
2601 #endif
2602 
2603 static HANDLE    _hProcess;
2604 static HANDLE    _hToken;
2605 
2606 // Container for NUMA node list info
2607 class NUMANodeListHolder {
2608  private:
2609   int *_numa_used_node_list;  // allocated below
2610   int _numa_used_node_count;
2611 
2612   void free_node_list() {
2613     if (_numa_used_node_list != NULL) {
2614       FREE_C_HEAP_ARRAY(int, _numa_used_node_list);
2615     }
2616   }
2617 
2618  public:
2619   NUMANodeListHolder() {
2620     _numa_used_node_count = 0;
2621     _numa_used_node_list = NULL;
2622     // do rest of initialization in build routine (after function pointers are set up)
2623   }
2624 
2625   ~NUMANodeListHolder() {
2626     free_node_list();
2627   }
2628 
2629   bool build() {
2630     DWORD_PTR proc_aff_mask;
2631     DWORD_PTR sys_aff_mask;
2632     if (!GetProcessAffinityMask(GetCurrentProcess(), &proc_aff_mask, &sys_aff_mask)) return false;
2633     ULONG highest_node_number;
2634     if (!GetNumaHighestNodeNumber(&highest_node_number)) return false;
2635     free_node_list();
2636     _numa_used_node_list = NEW_C_HEAP_ARRAY(int, highest_node_number + 1, mtInternal);
2637     for (unsigned int i = 0; i <= highest_node_number; i++) {
2638       ULONGLONG proc_mask_numa_node;
2639       if (!GetNumaNodeProcessorMask(i, &proc_mask_numa_node)) return false;
2640       if ((proc_aff_mask & proc_mask_numa_node)!=0) {
2641         _numa_used_node_list[_numa_used_node_count++] = i;
2642       }
2643     }
2644     return (_numa_used_node_count > 1);
2645   }
2646 
2647   int get_count() { return _numa_used_node_count; }
2648   int get_node_list_entry(int n) {
2649     // for indexes out of range, returns -1
2650     return (n < _numa_used_node_count ? _numa_used_node_list[n] : -1);
2651   }
2652 
2653 } numa_node_list_holder;
2654 
2655 
2656 
2657 static size_t _large_page_size = 0;
2658 
2659 static bool request_lock_memory_privilege() {
2660   _hProcess = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE,
2661                           os::current_process_id());
2662 
2663   LUID luid;
2664   if (_hProcess != NULL &&
2665       OpenProcessToken(_hProcess, TOKEN_ADJUST_PRIVILEGES, &_hToken) &&
2666       LookupPrivilegeValue(NULL, "SeLockMemoryPrivilege", &luid)) {
2667 
2668     TOKEN_PRIVILEGES tp;
2669     tp.PrivilegeCount = 1;
2670     tp.Privileges[0].Luid = luid;
2671     tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
2672 
2673     // AdjustTokenPrivileges() may return TRUE even when it couldn't change the
2674     // privilege. Check GetLastError() too. See MSDN document.
2675     if (AdjustTokenPrivileges(_hToken, false, &tp, sizeof(tp), NULL, NULL) &&
2676         (GetLastError() == ERROR_SUCCESS)) {
2677       return true;
2678     }
2679   }
2680 
2681   return false;
2682 }
2683 
2684 static void cleanup_after_large_page_init() {
2685   if (_hProcess) CloseHandle(_hProcess);
2686   _hProcess = NULL;
2687   if (_hToken) CloseHandle(_hToken);
2688   _hToken = NULL;
2689 }
2690 
2691 static bool numa_interleaving_init() {
2692   bool success = false;
2693   bool use_numa_interleaving_specified = !FLAG_IS_DEFAULT(UseNUMAInterleaving);
2694 
2695   // print a warning if UseNUMAInterleaving flag is specified on command line
2696   bool warn_on_failure = use_numa_interleaving_specified;
2697 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2698 
2699   // NUMAInterleaveGranularity cannot be less than vm_allocation_granularity (or _large_page_size if using large pages)
2700   size_t min_interleave_granularity = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2701   NUMAInterleaveGranularity = align_up(NUMAInterleaveGranularity, min_interleave_granularity);
2702 
2703   if (numa_node_list_holder.build()) {
2704     if (log_is_enabled(Debug, os, cpu)) {
2705       Log(os, cpu) log;
2706       log.debug("NUMA UsedNodeCount=%d, namely ", numa_node_list_holder.get_count());
2707       for (int i = 0; i < numa_node_list_holder.get_count(); i++) {
2708         log.debug("  %d ", numa_node_list_holder.get_node_list_entry(i));
2709       }
2710     }
2711     success = true;
2712   } else {
2713     WARN("Process does not cover multiple NUMA nodes.");
2714   }
2715   if (!success) {
2716     if (use_numa_interleaving_specified) WARN("...Ignoring UseNUMAInterleaving flag.");
2717   }
2718   return success;
2719 #undef WARN
2720 }
2721 
2722 // this routine is used whenever we need to reserve a contiguous VA range
2723 // but we need to make separate VirtualAlloc calls for each piece of the range
2724 // Reasons for doing this:
2725 //  * UseLargePagesIndividualAllocation was set (normally only needed on WS2003 but possible to be set otherwise)
2726 //  * UseNUMAInterleaving requires a separate node for each piece
2727 static char* allocate_pages_individually(size_t bytes, char* addr, DWORD flags,
2728                                          DWORD prot,
2729                                          bool should_inject_error = false) {
2730   char * p_buf;
2731   // note: at setup time we guaranteed that NUMAInterleaveGranularity was aligned up to a page size
2732   size_t page_size = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2733   size_t chunk_size = UseNUMAInterleaving ? NUMAInterleaveGranularity : page_size;
2734 
2735   // first reserve enough address space in advance since we want to be
2736   // able to break a single contiguous virtual address range into multiple
2737   // large page commits but WS2003 does not allow reserving large page space
2738   // so we just use 4K pages for reserve, this gives us a legal contiguous
2739   // address space. then we will deallocate that reservation, and re alloc
2740   // using large pages
2741   const size_t size_of_reserve = bytes + chunk_size;
2742   if (bytes > size_of_reserve) {
2743     // Overflowed.
2744     return NULL;
2745   }
2746   p_buf = (char *) VirtualAlloc(addr,
2747                                 size_of_reserve,  // size of Reserve
2748                                 MEM_RESERVE,
2749                                 PAGE_READWRITE);
2750   // If reservation failed, return NULL
2751   if (p_buf == NULL) return NULL;
2752   MemTracker::record_virtual_memory_reserve((address)p_buf, size_of_reserve, CALLER_PC);
2753   os::release_memory(p_buf, bytes + chunk_size);
2754 
2755   // we still need to round up to a page boundary (in case we are using large pages)
2756   // but not to a chunk boundary (in case InterleavingGranularity doesn't align with page size)
2757   // instead we handle this in the bytes_to_rq computation below
2758   p_buf = align_up(p_buf, page_size);
2759 
2760   // now go through and allocate one chunk at a time until all bytes are
2761   // allocated
2762   size_t  bytes_remaining = bytes;
2763   // An overflow of align_up() would have been caught above
2764   // in the calculation of size_of_reserve.
2765   char * next_alloc_addr = p_buf;
2766   HANDLE hProc = GetCurrentProcess();
2767 
2768 #ifdef ASSERT
2769   // Variable for the failure injection
2770   int ran_num = os::random();
2771   size_t fail_after = ran_num % bytes;
2772 #endif
2773 
2774   int count=0;
2775   while (bytes_remaining) {
2776     // select bytes_to_rq to get to the next chunk_size boundary
2777 
2778     size_t bytes_to_rq = MIN2(bytes_remaining, chunk_size - ((size_t)next_alloc_addr % chunk_size));
2779     // Note allocate and commit
2780     char * p_new;
2781 
2782 #ifdef ASSERT
2783     bool inject_error_now = should_inject_error && (bytes_remaining <= fail_after);
2784 #else
2785     const bool inject_error_now = false;
2786 #endif
2787 
2788     if (inject_error_now) {
2789       p_new = NULL;
2790     } else {
2791       if (!UseNUMAInterleaving) {
2792         p_new = (char *) VirtualAlloc(next_alloc_addr,
2793                                       bytes_to_rq,
2794                                       flags,
2795                                       prot);
2796       } else {
2797         // get the next node to use from the used_node_list
2798         assert(numa_node_list_holder.get_count() > 0, "Multiple NUMA nodes expected");
2799         DWORD node = numa_node_list_holder.get_node_list_entry(count % numa_node_list_holder.get_count());
2800         p_new = (char *)VirtualAllocExNuma(hProc, next_alloc_addr, bytes_to_rq, flags, prot, node);
2801       }
2802     }
2803 
2804     if (p_new == NULL) {
2805       // Free any allocated pages
2806       if (next_alloc_addr > p_buf) {
2807         // Some memory was committed so release it.
2808         size_t bytes_to_release = bytes - bytes_remaining;
2809         // NMT has yet to record any individual blocks, so it
2810         // need to create a dummy 'reserve' record to match
2811         // the release.
2812         MemTracker::record_virtual_memory_reserve((address)p_buf,
2813                                                   bytes_to_release, CALLER_PC);
2814         os::release_memory(p_buf, bytes_to_release);
2815       }
2816 #ifdef ASSERT
2817       if (should_inject_error) {
2818         log_develop_debug(pagesize)("Reserving pages individually failed.");
2819       }
2820 #endif
2821       return NULL;
2822     }
2823 
2824     bytes_remaining -= bytes_to_rq;
2825     next_alloc_addr += bytes_to_rq;
2826     count++;
2827   }
2828   // Although the memory is allocated individually, it is returned as one.
2829   // NMT records it as one block.
2830   if ((flags & MEM_COMMIT) != 0) {
2831     MemTracker::record_virtual_memory_reserve_and_commit((address)p_buf, bytes, CALLER_PC);
2832   } else {
2833     MemTracker::record_virtual_memory_reserve((address)p_buf, bytes, CALLER_PC);
2834   }
2835 
2836   // made it this far, success
2837   return p_buf;
2838 }
2839 
2840 
2841 
2842 void os::large_page_init() {
2843   if (!UseLargePages) return;
2844 
2845   // print a warning if any large page related flag is specified on command line
2846   bool warn_on_failure = !FLAG_IS_DEFAULT(UseLargePages) ||
2847                          !FLAG_IS_DEFAULT(LargePageSizeInBytes);
2848   bool success = false;
2849 
2850 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2851   if (request_lock_memory_privilege()) {
2852     size_t s = GetLargePageMinimum();
2853     if (s) {
2854 #if defined(IA32) || defined(AMD64)
2855       if (s > 4*M || LargePageSizeInBytes > 4*M) {
2856         WARN("JVM cannot use large pages bigger than 4mb.");
2857       } else {
2858 #endif
2859         if (LargePageSizeInBytes && LargePageSizeInBytes % s == 0) {
2860           _large_page_size = LargePageSizeInBytes;
2861         } else {
2862           _large_page_size = s;
2863         }
2864         success = true;
2865 #if defined(IA32) || defined(AMD64)
2866       }
2867 #endif
2868     } else {
2869       WARN("Large page is not supported by the processor.");
2870     }
2871   } else {
2872     WARN("JVM cannot use large page memory because it does not have enough privilege to lock pages in memory.");
2873   }
2874 #undef WARN
2875 
2876   const size_t default_page_size = (size_t) vm_page_size();
2877   if (success && _large_page_size > default_page_size) {
2878     _page_sizes[0] = _large_page_size;
2879     _page_sizes[1] = default_page_size;
2880     _page_sizes[2] = 0;
2881   }
2882 
2883   cleanup_after_large_page_init();
2884   UseLargePages = success;
2885 }
2886 
2887 // On win32, one cannot release just a part of reserved memory, it's an
2888 // all or nothing deal.  When we split a reservation, we must break the
2889 // reservation into two reservations.
2890 void os::pd_split_reserved_memory(char *base, size_t size, size_t split,
2891                                   bool realloc) {
2892   if (size > 0) {
2893     release_memory(base, size);
2894     if (realloc) {
2895       reserve_memory(split, base);
2896     }
2897     if (size != split) {
2898       reserve_memory(size - split, base + split);
2899     }
2900   }
2901 }
2902 
2903 // Multiple threads can race in this code but it's not possible to unmap small sections of
2904 // virtual space to get requested alignment, like posix-like os's.
2905 // Windows prevents multiple thread from remapping over each other so this loop is thread-safe.
2906 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
2907   assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
2908          "Alignment must be a multiple of allocation granularity (page size)");
2909   assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
2910 
2911   size_t extra_size = size + alignment;
2912   assert(extra_size >= size, "overflow, size is too large to allow alignment");
2913 
2914   char* aligned_base = NULL;
2915 
2916   do {
2917     char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
2918     if (extra_base == NULL) {
2919       return NULL;
2920     }
2921     // Do manual alignment
2922     aligned_base = align_up(extra_base, alignment);
2923 
2924     os::release_memory(extra_base, extra_size);
2925 
2926     aligned_base = os::reserve_memory(size, aligned_base);
2927 
2928   } while (aligned_base == NULL);
2929 
2930   return aligned_base;
2931 }
2932 
2933 char* os::pd_reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
2934   assert((size_t)addr % os::vm_allocation_granularity() == 0,
2935          "reserve alignment");
2936   assert(bytes % os::vm_page_size() == 0, "reserve page size");
2937   char* res;
2938   // note that if UseLargePages is on, all the areas that require interleaving
2939   // will go thru reserve_memory_special rather than thru here.
2940   bool use_individual = (UseNUMAInterleaving && !UseLargePages);
2941   if (!use_individual) {
2942     res = (char*)VirtualAlloc(addr, bytes, MEM_RESERVE, PAGE_READWRITE);
2943   } else {
2944     elapsedTimer reserveTimer;
2945     if (Verbose && PrintMiscellaneous) reserveTimer.start();
2946     // in numa interleaving, we have to allocate pages individually
2947     // (well really chunks of NUMAInterleaveGranularity size)
2948     res = allocate_pages_individually(bytes, addr, MEM_RESERVE, PAGE_READWRITE);
2949     if (res == NULL) {
2950       warning("NUMA page allocation failed");
2951     }
2952     if (Verbose && PrintMiscellaneous) {
2953       reserveTimer.stop();
2954       tty->print_cr("reserve_memory of %Ix bytes took " JLONG_FORMAT " ms (" JLONG_FORMAT " ticks)", bytes,
2955                     reserveTimer.milliseconds(), reserveTimer.ticks());
2956     }
2957   }
2958   assert(res == NULL || addr == NULL || addr == res,
2959          "Unexpected address from reserve.");
2960 
2961   return res;
2962 }
2963 
2964 // Reserve memory at an arbitrary address, only if that area is
2965 // available (and not reserved for something else).
2966 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2967   // Windows os::reserve_memory() fails of the requested address range is
2968   // not avilable.
2969   return reserve_memory(bytes, requested_addr);
2970 }
2971 
2972 size_t os::large_page_size() {
2973   return _large_page_size;
2974 }
2975 
2976 bool os::can_commit_large_page_memory() {
2977   // Windows only uses large page memory when the entire region is reserved
2978   // and committed in a single VirtualAlloc() call. This may change in the
2979   // future, but with Windows 2003 it's not possible to commit on demand.
2980   return false;
2981 }
2982 
2983 bool os::can_execute_large_page_memory() {
2984   return true;
2985 }
2986 
2987 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* addr,
2988                                  bool exec) {
2989   assert(UseLargePages, "only for large pages");
2990 
2991   if (!is_aligned(bytes, os::large_page_size()) || alignment > os::large_page_size()) {
2992     return NULL; // Fallback to small pages.
2993   }
2994 
2995   const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
2996   const DWORD flags = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
2997 
2998   // with large pages, there are two cases where we need to use Individual Allocation
2999   // 1) the UseLargePagesIndividualAllocation flag is set (set by default on WS2003)
3000   // 2) NUMA Interleaving is enabled, in which case we use a different node for each page
3001   if (UseLargePagesIndividualAllocation || UseNUMAInterleaving) {
3002     log_debug(pagesize)("Reserving large pages individually.");
3003 
3004     char * p_buf = allocate_pages_individually(bytes, addr, flags, prot, LargePagesIndividualAllocationInjectError);
3005     if (p_buf == NULL) {
3006       // give an appropriate warning message
3007       if (UseNUMAInterleaving) {
3008         warning("NUMA large page allocation failed, UseLargePages flag ignored");
3009       }
3010       if (UseLargePagesIndividualAllocation) {
3011         warning("Individually allocated large pages failed, "
3012                 "use -XX:-UseLargePagesIndividualAllocation to turn off");
3013       }
3014       return NULL;
3015     }
3016 
3017     return p_buf;
3018 
3019   } else {
3020     log_debug(pagesize)("Reserving large pages in a single large chunk.");
3021 
3022     // normal policy just allocate it all at once
3023     DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
3024     char * res = (char *)VirtualAlloc(addr, bytes, flag, prot);
3025     if (res != NULL) {
3026       MemTracker::record_virtual_memory_reserve_and_commit((address)res, bytes, CALLER_PC);
3027     }
3028 
3029     return res;
3030   }
3031 }
3032 
3033 bool os::release_memory_special(char* base, size_t bytes) {
3034   assert(base != NULL, "Sanity check");
3035   return release_memory(base, bytes);
3036 }
3037 
3038 void os::print_statistics() {
3039 }
3040 
3041 static void warn_fail_commit_memory(char* addr, size_t bytes, bool exec) {
3042   int err = os::get_last_error();
3043   char buf[256];
3044   size_t buf_len = os::lasterror(buf, sizeof(buf));
3045   warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
3046           ", %d) failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3047           exec, buf_len != 0 ? buf : "<no_error_string>", err);
3048 }
3049 
3050 bool os::pd_commit_memory(char* addr, size_t bytes, bool exec) {
3051   if (bytes == 0) {
3052     // Don't bother the OS with noops.
3053     return true;
3054   }
3055   assert((size_t) addr % os::vm_page_size() == 0, "commit on page boundaries");
3056   assert(bytes % os::vm_page_size() == 0, "commit in page-sized chunks");
3057   // Don't attempt to print anything if the OS call fails. We're
3058   // probably low on resources, so the print itself may cause crashes.
3059 
3060   // unless we have NUMAInterleaving enabled, the range of a commit
3061   // is always within a reserve covered by a single VirtualAlloc
3062   // in that case we can just do a single commit for the requested size
3063   if (!UseNUMAInterleaving) {
3064     if (VirtualAlloc(addr, bytes, MEM_COMMIT, PAGE_READWRITE) == NULL) {
3065       NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3066       return false;
3067     }
3068     if (exec) {
3069       DWORD oldprot;
3070       // Windows doc says to use VirtualProtect to get execute permissions
3071       if (!VirtualProtect(addr, bytes, PAGE_EXECUTE_READWRITE, &oldprot)) {
3072         NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3073         return false;
3074       }
3075     }
3076     return true;
3077   } else {
3078 
3079     // when NUMAInterleaving is enabled, the commit might cover a range that
3080     // came from multiple VirtualAlloc reserves (using allocate_pages_individually).
3081     // VirtualQuery can help us determine that.  The RegionSize that VirtualQuery
3082     // returns represents the number of bytes that can be committed in one step.
3083     size_t bytes_remaining = bytes;
3084     char * next_alloc_addr = addr;
3085     while (bytes_remaining > 0) {
3086       MEMORY_BASIC_INFORMATION alloc_info;
3087       VirtualQuery(next_alloc_addr, &alloc_info, sizeof(alloc_info));
3088       size_t bytes_to_rq = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3089       if (VirtualAlloc(next_alloc_addr, bytes_to_rq, MEM_COMMIT,
3090                        PAGE_READWRITE) == NULL) {
3091         NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3092                                             exec);)
3093         return false;
3094       }
3095       if (exec) {
3096         DWORD oldprot;
3097         if (!VirtualProtect(next_alloc_addr, bytes_to_rq,
3098                             PAGE_EXECUTE_READWRITE, &oldprot)) {
3099           NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3100                                               exec);)
3101           return false;
3102         }
3103       }
3104       bytes_remaining -= bytes_to_rq;
3105       next_alloc_addr += bytes_to_rq;
3106     }
3107   }
3108   // if we made it this far, return true
3109   return true;
3110 }
3111 
3112 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
3113                           bool exec) {
3114   // alignment_hint is ignored on this OS
3115   return pd_commit_memory(addr, size, exec);
3116 }
3117 
3118 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
3119                                   const char* mesg) {
3120   assert(mesg != NULL, "mesg must be specified");
3121   if (!pd_commit_memory(addr, size, exec)) {
3122     warn_fail_commit_memory(addr, size, exec);
3123     vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
3124   }
3125 }
3126 
3127 void os::pd_commit_memory_or_exit(char* addr, size_t size,
3128                                   size_t alignment_hint, bool exec,
3129                                   const char* mesg) {
3130   // alignment_hint is ignored on this OS
3131   pd_commit_memory_or_exit(addr, size, exec, mesg);
3132 }
3133 
3134 bool os::pd_uncommit_memory(char* addr, size_t bytes) {
3135   if (bytes == 0) {
3136     // Don't bother the OS with noops.
3137     return true;
3138   }
3139   assert((size_t) addr % os::vm_page_size() == 0, "uncommit on page boundaries");
3140   assert(bytes % os::vm_page_size() == 0, "uncommit in page-sized chunks");
3141   return (VirtualFree(addr, bytes, MEM_DECOMMIT) != 0);
3142 }
3143 
3144 bool os::pd_release_memory(char* addr, size_t bytes) {
3145   return VirtualFree(addr, 0, MEM_RELEASE) != 0;
3146 }
3147 
3148 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
3149   return os::commit_memory(addr, size, !ExecMem);
3150 }
3151 
3152 bool os::remove_stack_guard_pages(char* addr, size_t size) {
3153   return os::uncommit_memory(addr, size);
3154 }
3155 
3156 static bool protect_pages_individually(char* addr, size_t bytes, unsigned int p, DWORD *old_status) {
3157   uint count = 0;
3158   bool ret = false;
3159   size_t bytes_remaining = bytes;
3160   char * next_protect_addr = addr;
3161 
3162   // Use VirtualQuery() to get the chunk size.
3163   while (bytes_remaining) {
3164     MEMORY_BASIC_INFORMATION alloc_info;
3165     if (VirtualQuery(next_protect_addr, &alloc_info, sizeof(alloc_info)) == 0) {
3166       return false;
3167     }
3168 
3169     size_t bytes_to_protect = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3170     // We used different API at allocate_pages_individually() based on UseNUMAInterleaving,
3171     // but we don't distinguish here as both cases are protected by same API.
3172     ret = VirtualProtect(next_protect_addr, bytes_to_protect, p, old_status) != 0;
3173     warning("Failed protecting pages individually for chunk #%u", count);
3174     if (!ret) {
3175       return false;
3176     }
3177 
3178     bytes_remaining -= bytes_to_protect;
3179     next_protect_addr += bytes_to_protect;
3180     count++;
3181   }
3182   return ret;
3183 }
3184 
3185 // Set protections specified
3186 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
3187                         bool is_committed) {
3188   unsigned int p = 0;
3189   switch (prot) {
3190   case MEM_PROT_NONE: p = PAGE_NOACCESS; break;
3191   case MEM_PROT_READ: p = PAGE_READONLY; break;
3192   case MEM_PROT_RW:   p = PAGE_READWRITE; break;
3193   case MEM_PROT_RWX:  p = PAGE_EXECUTE_READWRITE; break;
3194   default:
3195     ShouldNotReachHere();
3196   }
3197 
3198   DWORD old_status;
3199 
3200   // Strange enough, but on Win32 one can change protection only for committed
3201   // memory, not a big deal anyway, as bytes less or equal than 64K
3202   if (!is_committed) {
3203     commit_memory_or_exit(addr, bytes, prot == MEM_PROT_RWX,
3204                           "cannot commit protection page");
3205   }
3206   // One cannot use os::guard_memory() here, as on Win32 guard page
3207   // have different (one-shot) semantics, from MSDN on PAGE_GUARD:
3208   //
3209   // Pages in the region become guard pages. Any attempt to access a guard page
3210   // causes the system to raise a STATUS_GUARD_PAGE exception and turn off
3211   // the guard page status. Guard pages thus act as a one-time access alarm.
3212   bool ret;
3213   if (UseNUMAInterleaving) {
3214     // If UseNUMAInterleaving is enabled, the pages may have been allocated a chunk at a time,
3215     // so we must protect the chunks individually.
3216     ret = protect_pages_individually(addr, bytes, p, &old_status);
3217   } else {
3218     ret = VirtualProtect(addr, bytes, p, &old_status) != 0;
3219   }
3220 #ifdef ASSERT
3221   if (!ret) {
3222     int err = os::get_last_error();
3223     char buf[256];
3224     size_t buf_len = os::lasterror(buf, sizeof(buf));
3225     warning("INFO: os::protect_memory(" PTR_FORMAT ", " SIZE_FORMAT
3226           ") failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3227           buf_len != 0 ? buf : "<no_error_string>", err);
3228   }
3229 #endif
3230   return ret;
3231 }
3232 
3233 bool os::guard_memory(char* addr, size_t bytes) {
3234   DWORD old_status;
3235   return VirtualProtect(addr, bytes, PAGE_READWRITE | PAGE_GUARD, &old_status) != 0;
3236 }
3237 
3238 bool os::unguard_memory(char* addr, size_t bytes) {
3239   DWORD old_status;
3240   return VirtualProtect(addr, bytes, PAGE_READWRITE, &old_status) != 0;
3241 }
3242 
3243 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3244 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3245 void os::numa_make_global(char *addr, size_t bytes)    { }
3246 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint)    { }
3247 bool os::numa_topology_changed()                       { return false; }
3248 size_t os::numa_get_groups_num()                       { return MAX2(numa_node_list_holder.get_count(), 1); }
3249 int os::numa_get_group_id()                            { return 0; }
3250 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
3251   if (numa_node_list_holder.get_count() == 0 && size > 0) {
3252     // Provide an answer for UMA systems
3253     ids[0] = 0;
3254     return 1;
3255   } else {
3256     // check for size bigger than actual groups_num
3257     size = MIN2(size, numa_get_groups_num());
3258     for (int i = 0; i < (int)size; i++) {
3259       ids[i] = numa_node_list_holder.get_node_list_entry(i);
3260     }
3261     return size;
3262   }
3263 }
3264 
3265 bool os::get_page_info(char *start, page_info* info) {
3266   return false;
3267 }
3268 
3269 char *os::scan_pages(char *start, char* end, page_info* page_expected,
3270                      page_info* page_found) {
3271   return end;
3272 }
3273 
3274 char* os::non_memory_address_word() {
3275   // Must never look like an address returned by reserve_memory,
3276   // even in its subfields (as defined by the CPU immediate fields,
3277   // if the CPU splits constants across multiple instructions).
3278   return (char*)-1;
3279 }
3280 
3281 #define MAX_ERROR_COUNT 100
3282 #define SYS_THREAD_ERROR 0xffffffffUL
3283 
3284 void os::pd_start_thread(Thread* thread) {
3285   DWORD ret = ResumeThread(thread->osthread()->thread_handle());
3286   // Returns previous suspend state:
3287   // 0:  Thread was not suspended
3288   // 1:  Thread is running now
3289   // >1: Thread is still suspended.
3290   assert(ret != SYS_THREAD_ERROR, "StartThread failed"); // should propagate back
3291 }
3292 
3293 class HighResolutionInterval : public CHeapObj<mtThread> {
3294   // The default timer resolution seems to be 10 milliseconds.
3295   // (Where is this written down?)
3296   // If someone wants to sleep for only a fraction of the default,
3297   // then we set the timer resolution down to 1 millisecond for
3298   // the duration of their interval.
3299   // We carefully set the resolution back, since otherwise we
3300   // seem to incur an overhead (3%?) that we don't need.
3301   // CONSIDER: if ms is small, say 3, then we should run with a high resolution time.
3302   // Buf if ms is large, say 500, or 503, we should avoid the call to timeBeginPeriod().
3303   // Alternatively, we could compute the relative error (503/500 = .6%) and only use
3304   // timeBeginPeriod() if the relative error exceeded some threshold.
3305   // timeBeginPeriod() has been linked to problems with clock drift on win32 systems and
3306   // to decreased efficiency related to increased timer "tick" rates.  We want to minimize
3307   // (a) calls to timeBeginPeriod() and timeEndPeriod() and (b) time spent with high
3308   // resolution timers running.
3309  private:
3310   jlong resolution;
3311  public:
3312   HighResolutionInterval(jlong ms) {
3313     resolution = ms % 10L;
3314     if (resolution != 0) {
3315       MMRESULT result = timeBeginPeriod(1L);
3316     }
3317   }
3318   ~HighResolutionInterval() {
3319     if (resolution != 0) {
3320       MMRESULT result = timeEndPeriod(1L);
3321     }
3322     resolution = 0L;
3323   }
3324 };
3325 
3326 int os::sleep(Thread* thread, jlong ms, bool interruptable) {
3327   jlong limit = (jlong) MAXDWORD;
3328 
3329   while (ms > limit) {
3330     int res;
3331     if ((res = sleep(thread, limit, interruptable)) != OS_TIMEOUT) {
3332       return res;
3333     }
3334     ms -= limit;
3335   }
3336 
3337   assert(thread == Thread::current(), "thread consistency check");
3338   OSThread* osthread = thread->osthread();
3339   OSThreadWaitState osts(osthread, false /* not Object.wait() */);
3340   int result;
3341   if (interruptable) {
3342     assert(thread->is_Java_thread(), "must be java thread");
3343     JavaThread *jt = (JavaThread *) thread;
3344     ThreadBlockInVM tbivm(jt);
3345 
3346     jt->set_suspend_equivalent();
3347     // cleared by handle_special_suspend_equivalent_condition() or
3348     // java_suspend_self() via check_and_wait_while_suspended()
3349 
3350     HANDLE events[1];
3351     events[0] = osthread->interrupt_event();
3352     HighResolutionInterval *phri=NULL;
3353     if (!ForceTimeHighResolution) {
3354       phri = new HighResolutionInterval(ms);
3355     }
3356     if (WaitForMultipleObjects(1, events, FALSE, (DWORD)ms) == WAIT_TIMEOUT) {
3357       result = OS_TIMEOUT;
3358     } else {
3359       ResetEvent(osthread->interrupt_event());
3360       osthread->set_interrupted(false);
3361       result = OS_INTRPT;
3362     }
3363     delete phri; //if it is NULL, harmless
3364 
3365     // were we externally suspended while we were waiting?
3366     jt->check_and_wait_while_suspended();
3367   } else {
3368     assert(!thread->is_Java_thread(), "must not be java thread");
3369     Sleep((long) ms);
3370     result = OS_TIMEOUT;
3371   }
3372   return result;
3373 }
3374 
3375 // Short sleep, direct OS call.
3376 //
3377 // ms = 0, means allow others (if any) to run.
3378 //
3379 void os::naked_short_sleep(jlong ms) {
3380   assert(ms < 1000, "Un-interruptable sleep, short time use only");
3381   Sleep(ms);
3382 }
3383 
3384 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
3385 void os::infinite_sleep() {
3386   while (true) {    // sleep forever ...
3387     Sleep(100000);  // ... 100 seconds at a time
3388   }
3389 }
3390 
3391 typedef BOOL (WINAPI * STTSignature)(void);
3392 
3393 void os::naked_yield() {
3394   // Consider passing back the return value from SwitchToThread().
3395   SwitchToThread();
3396 }
3397 
3398 // Win32 only gives you access to seven real priorities at a time,
3399 // so we compress Java's ten down to seven.  It would be better
3400 // if we dynamically adjusted relative priorities.
3401 
3402 int os::java_to_os_priority[CriticalPriority + 1] = {
3403   THREAD_PRIORITY_IDLE,                         // 0  Entry should never be used
3404   THREAD_PRIORITY_LOWEST,                       // 1  MinPriority
3405   THREAD_PRIORITY_LOWEST,                       // 2
3406   THREAD_PRIORITY_BELOW_NORMAL,                 // 3
3407   THREAD_PRIORITY_BELOW_NORMAL,                 // 4
3408   THREAD_PRIORITY_NORMAL,                       // 5  NormPriority
3409   THREAD_PRIORITY_NORMAL,                       // 6
3410   THREAD_PRIORITY_ABOVE_NORMAL,                 // 7
3411   THREAD_PRIORITY_ABOVE_NORMAL,                 // 8
3412   THREAD_PRIORITY_HIGHEST,                      // 9  NearMaxPriority
3413   THREAD_PRIORITY_HIGHEST,                      // 10 MaxPriority
3414   THREAD_PRIORITY_HIGHEST                       // 11 CriticalPriority
3415 };
3416 
3417 int prio_policy1[CriticalPriority + 1] = {
3418   THREAD_PRIORITY_IDLE,                         // 0  Entry should never be used
3419   THREAD_PRIORITY_LOWEST,                       // 1  MinPriority
3420   THREAD_PRIORITY_LOWEST,                       // 2
3421   THREAD_PRIORITY_BELOW_NORMAL,                 // 3
3422   THREAD_PRIORITY_BELOW_NORMAL,                 // 4
3423   THREAD_PRIORITY_NORMAL,                       // 5  NormPriority
3424   THREAD_PRIORITY_ABOVE_NORMAL,                 // 6
3425   THREAD_PRIORITY_ABOVE_NORMAL,                 // 7
3426   THREAD_PRIORITY_HIGHEST,                      // 8
3427   THREAD_PRIORITY_HIGHEST,                      // 9  NearMaxPriority
3428   THREAD_PRIORITY_TIME_CRITICAL,                // 10 MaxPriority
3429   THREAD_PRIORITY_TIME_CRITICAL                 // 11 CriticalPriority
3430 };
3431 
3432 static int prio_init() {
3433   // If ThreadPriorityPolicy is 1, switch tables
3434   if (ThreadPriorityPolicy == 1) {
3435     int i;
3436     for (i = 0; i < CriticalPriority + 1; i++) {
3437       os::java_to_os_priority[i] = prio_policy1[i];
3438     }
3439   }
3440   if (UseCriticalJavaThreadPriority) {
3441     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
3442   }
3443   return 0;
3444 }
3445 
3446 OSReturn os::set_native_priority(Thread* thread, int priority) {
3447   if (!UseThreadPriorities) return OS_OK;
3448   bool ret = SetThreadPriority(thread->osthread()->thread_handle(), priority) != 0;
3449   return ret ? OS_OK : OS_ERR;
3450 }
3451 
3452 OSReturn os::get_native_priority(const Thread* const thread,
3453                                  int* priority_ptr) {
3454   if (!UseThreadPriorities) {
3455     *priority_ptr = java_to_os_priority[NormPriority];
3456     return OS_OK;
3457   }
3458   int os_prio = GetThreadPriority(thread->osthread()->thread_handle());
3459   if (os_prio == THREAD_PRIORITY_ERROR_RETURN) {
3460     assert(false, "GetThreadPriority failed");
3461     return OS_ERR;
3462   }
3463   *priority_ptr = os_prio;
3464   return OS_OK;
3465 }
3466 
3467 
3468 // Hint to the underlying OS that a task switch would not be good.
3469 // Void return because it's a hint and can fail.
3470 void os::hint_no_preempt() {}
3471 
3472 void os::interrupt(Thread* thread) {
3473   assert(!thread->is_Java_thread() || Thread::current() == thread ||
3474          Threads_lock->owned_by_self(),
3475          "possibility of dangling Thread pointer");
3476 
3477   OSThread* osthread = thread->osthread();
3478   osthread->set_interrupted(true);
3479   // More than one thread can get here with the same value of osthread,
3480   // resulting in multiple notifications.  We do, however, want the store
3481   // to interrupted() to be visible to other threads before we post
3482   // the interrupt event.
3483   OrderAccess::release();
3484   SetEvent(osthread->interrupt_event());
3485   // For JSR166:  unpark after setting status
3486   if (thread->is_Java_thread()) {
3487     ((JavaThread*)thread)->parker()->unpark();
3488   }
3489 
3490   ParkEvent * ev = thread->_ParkEvent;
3491   if (ev != NULL) ev->unpark();
3492 }
3493 
3494 
3495 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3496   assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
3497          "possibility of dangling Thread pointer");
3498 
3499   OSThread* osthread = thread->osthread();
3500   // There is no synchronization between the setting of the interrupt
3501   // and it being cleared here. It is critical - see 6535709 - that
3502   // we only clear the interrupt state, and reset the interrupt event,
3503   // if we are going to report that we were indeed interrupted - else
3504   // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
3505   // depending on the timing. By checking thread interrupt event to see
3506   // if the thread gets real interrupt thus prevent spurious wakeup.
3507   bool interrupted = osthread->interrupted() && (WaitForSingleObject(osthread->interrupt_event(), 0) == WAIT_OBJECT_0);
3508   if (interrupted && clear_interrupted) {
3509     osthread->set_interrupted(false);
3510     ResetEvent(osthread->interrupt_event());
3511   } // Otherwise leave the interrupted state alone
3512 
3513   return interrupted;
3514 }
3515 
3516 // Get's a pc (hint) for a running thread. Currently used only for profiling.
3517 ExtendedPC os::get_thread_pc(Thread* thread) {
3518   CONTEXT context;
3519   context.ContextFlags = CONTEXT_CONTROL;
3520   HANDLE handle = thread->osthread()->thread_handle();
3521   if (GetThreadContext(handle, &context)) {
3522 #ifdef _M_AMD64
3523     return ExtendedPC((address) context.Rip);
3524 #else
3525     return ExtendedPC((address) context.Eip);
3526 #endif
3527   } else {
3528     return ExtendedPC(NULL);
3529   }
3530 }
3531 
3532 // GetCurrentThreadId() returns DWORD
3533 intx os::current_thread_id()  { return GetCurrentThreadId(); }
3534 
3535 static int _initial_pid = 0;
3536 
3537 int os::current_process_id() {
3538   return (_initial_pid ? _initial_pid : _getpid());
3539 }
3540 
3541 int    os::win32::_vm_page_size              = 0;
3542 int    os::win32::_vm_allocation_granularity = 0;
3543 int    os::win32::_processor_type            = 0;
3544 // Processor level is not available on non-NT systems, use vm_version instead
3545 int    os::win32::_processor_level           = 0;
3546 julong os::win32::_physical_memory           = 0;
3547 size_t os::win32::_default_stack_size        = 0;
3548 
3549 intx          os::win32::_os_thread_limit    = 0;
3550 volatile intx os::win32::_os_thread_count    = 0;
3551 
3552 bool   os::win32::_is_windows_server         = false;
3553 
3554 // 6573254
3555 // Currently, the bug is observed across all the supported Windows releases,
3556 // including the latest one (as of this writing - Windows Server 2012 R2)
3557 bool   os::win32::_has_exit_bug              = true;
3558 
3559 void os::win32::initialize_system_info() {
3560   SYSTEM_INFO si;
3561   GetSystemInfo(&si);
3562   _vm_page_size    = si.dwPageSize;
3563   _vm_allocation_granularity = si.dwAllocationGranularity;
3564   _processor_type  = si.dwProcessorType;
3565   _processor_level = si.wProcessorLevel;
3566   set_processor_count(si.dwNumberOfProcessors);
3567 
3568   MEMORYSTATUSEX ms;
3569   ms.dwLength = sizeof(ms);
3570 
3571   // also returns dwAvailPhys (free physical memory bytes), dwTotalVirtual, dwAvailVirtual,
3572   // dwMemoryLoad (% of memory in use)
3573   GlobalMemoryStatusEx(&ms);
3574   _physical_memory = ms.ullTotalPhys;
3575 
3576   if (FLAG_IS_DEFAULT(MaxRAM)) {
3577     // Adjust MaxRAM according to the maximum virtual address space available.
3578     FLAG_SET_DEFAULT(MaxRAM, MIN2(MaxRAM, (uint64_t) ms.ullTotalVirtual));
3579   }
3580 
3581   OSVERSIONINFOEX oi;
3582   oi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
3583   GetVersionEx((OSVERSIONINFO*)&oi);
3584   switch (oi.dwPlatformId) {
3585   case VER_PLATFORM_WIN32_NT:
3586     {
3587       int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
3588       if (oi.wProductType == VER_NT_DOMAIN_CONTROLLER ||
3589           oi.wProductType == VER_NT_SERVER) {
3590         _is_windows_server = true;
3591       }
3592     }
3593     break;
3594   default: fatal("Unknown platform");
3595   }
3596 
3597   _default_stack_size = os::current_stack_size();
3598   assert(_default_stack_size > (size_t) _vm_page_size, "invalid stack size");
3599   assert((_default_stack_size & (_vm_page_size - 1)) == 0,
3600          "stack size not a multiple of page size");
3601 
3602   initialize_performance_counter();
3603 }
3604 
3605 
3606 HINSTANCE os::win32::load_Windows_dll(const char* name, char *ebuf,
3607                                       int ebuflen) {
3608   char path[MAX_PATH];
3609   DWORD size;
3610   DWORD pathLen = (DWORD)sizeof(path);
3611   HINSTANCE result = NULL;
3612 
3613   // only allow library name without path component
3614   assert(strchr(name, '\\') == NULL, "path not allowed");
3615   assert(strchr(name, ':') == NULL, "path not allowed");
3616   if (strchr(name, '\\') != NULL || strchr(name, ':') != NULL) {
3617     jio_snprintf(ebuf, ebuflen,
3618                  "Invalid parameter while calling os::win32::load_windows_dll(): cannot take path: %s", name);
3619     return NULL;
3620   }
3621 
3622   // search system directory
3623   if ((size = GetSystemDirectory(path, pathLen)) > 0) {
3624     if (size >= pathLen) {
3625       return NULL; // truncated
3626     }
3627     if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3628       return NULL; // truncated
3629     }
3630     if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3631       return result;
3632     }
3633   }
3634 
3635   // try Windows directory
3636   if ((size = GetWindowsDirectory(path, pathLen)) > 0) {
3637     if (size >= pathLen) {
3638       return NULL; // truncated
3639     }
3640     if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3641       return NULL; // truncated
3642     }
3643     if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3644       return result;
3645     }
3646   }
3647 
3648   jio_snprintf(ebuf, ebuflen,
3649                "os::win32::load_windows_dll() cannot load %s from system directories.", name);
3650   return NULL;
3651 }
3652 
3653 #define MAXIMUM_THREADS_TO_KEEP (16 * MAXIMUM_WAIT_OBJECTS)
3654 #define EXIT_TIMEOUT 300000 /* 5 minutes */
3655 
3656 static BOOL CALLBACK init_crit_sect_call(PINIT_ONCE, PVOID pcrit_sect, PVOID*) {
3657   InitializeCriticalSection((CRITICAL_SECTION*)pcrit_sect);
3658   return TRUE;
3659 }
3660 
3661 int os::win32::exit_process_or_thread(Ept what, int exit_code) {
3662   // Basic approach:
3663   //  - Each exiting thread registers its intent to exit and then does so.
3664   //  - A thread trying to terminate the process must wait for all
3665   //    threads currently exiting to complete their exit.
3666 
3667   if (os::win32::has_exit_bug()) {
3668     // The array holds handles of the threads that have started exiting by calling
3669     // _endthreadex().
3670     // Should be large enough to avoid blocking the exiting thread due to lack of
3671     // a free slot.
3672     static HANDLE handles[MAXIMUM_THREADS_TO_KEEP];
3673     static int handle_count = 0;
3674 
3675     static INIT_ONCE init_once_crit_sect = INIT_ONCE_STATIC_INIT;
3676     static CRITICAL_SECTION crit_sect;
3677     static volatile jint process_exiting = 0;
3678     int i, j;
3679     DWORD res;
3680     HANDLE hproc, hthr;
3681 
3682     // We only attempt to register threads until a process exiting
3683     // thread manages to set the process_exiting flag. Any threads
3684     // that come through here after the process_exiting flag is set
3685     // are unregistered and will be caught in the SuspendThread()
3686     // infinite loop below.
3687     bool registered = false;
3688 
3689     // The first thread that reached this point, initializes the critical section.
3690     if (!InitOnceExecuteOnce(&init_once_crit_sect, init_crit_sect_call, &crit_sect, NULL)) {
3691       warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
3692     } else if (OrderAccess::load_acquire(&process_exiting) == 0) {
3693       if (what != EPT_THREAD) {
3694         // Atomically set process_exiting before the critical section
3695         // to increase the visibility between racing threads.
3696         Atomic::cmpxchg((jint)GetCurrentThreadId(), &process_exiting, 0);
3697       }
3698       EnterCriticalSection(&crit_sect);
3699 
3700       if (what == EPT_THREAD && OrderAccess::load_acquire(&process_exiting) == 0) {
3701         // Remove from the array those handles of the threads that have completed exiting.
3702         for (i = 0, j = 0; i < handle_count; ++i) {
3703           res = WaitForSingleObject(handles[i], 0 /* don't wait */);
3704           if (res == WAIT_TIMEOUT) {
3705             handles[j++] = handles[i];
3706           } else {
3707             if (res == WAIT_FAILED) {
3708               warning("WaitForSingleObject failed (%u) in %s: %d\n",
3709                       GetLastError(), __FILE__, __LINE__);
3710             }
3711             // Don't keep the handle, if we failed waiting for it.
3712             CloseHandle(handles[i]);
3713           }
3714         }
3715 
3716         // If there's no free slot in the array of the kept handles, we'll have to
3717         // wait until at least one thread completes exiting.
3718         if ((handle_count = j) == MAXIMUM_THREADS_TO_KEEP) {
3719           // Raise the priority of the oldest exiting thread to increase its chances
3720           // to complete sooner.
3721           SetThreadPriority(handles[0], THREAD_PRIORITY_ABOVE_NORMAL);
3722           res = WaitForMultipleObjects(MAXIMUM_WAIT_OBJECTS, handles, FALSE, EXIT_TIMEOUT);
3723           if (res >= WAIT_OBJECT_0 && res < (WAIT_OBJECT_0 + MAXIMUM_WAIT_OBJECTS)) {
3724             i = (res - WAIT_OBJECT_0);
3725             handle_count = MAXIMUM_THREADS_TO_KEEP - 1;
3726             for (; i < handle_count; ++i) {
3727               handles[i] = handles[i + 1];
3728             }
3729           } else {
3730             warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3731                     (res == WAIT_FAILED ? "failed" : "timed out"),
3732                     GetLastError(), __FILE__, __LINE__);
3733             // Don't keep handles, if we failed waiting for them.
3734             for (i = 0; i < MAXIMUM_THREADS_TO_KEEP; ++i) {
3735               CloseHandle(handles[i]);
3736             }
3737             handle_count = 0;
3738           }
3739         }
3740 
3741         // Store a duplicate of the current thread handle in the array of handles.
3742         hproc = GetCurrentProcess();
3743         hthr = GetCurrentThread();
3744         if (!DuplicateHandle(hproc, hthr, hproc, &handles[handle_count],
3745                              0, FALSE, DUPLICATE_SAME_ACCESS)) {
3746           warning("DuplicateHandle failed (%u) in %s: %d\n",
3747                   GetLastError(), __FILE__, __LINE__);
3748 
3749           // We can't register this thread (no more handles) so this thread
3750           // may be racing with a thread that is calling exit(). If the thread
3751           // that is calling exit() has managed to set the process_exiting
3752           // flag, then this thread will be caught in the SuspendThread()
3753           // infinite loop below which closes that race. A small timing
3754           // window remains before the process_exiting flag is set, but it
3755           // is only exposed when we are out of handles.
3756         } else {
3757           ++handle_count;
3758           registered = true;
3759 
3760           // The current exiting thread has stored its handle in the array, and now
3761           // should leave the critical section before calling _endthreadex().
3762         }
3763 
3764       } else if (what != EPT_THREAD && handle_count > 0) {
3765         jlong start_time, finish_time, timeout_left;
3766         // Before ending the process, make sure all the threads that had called
3767         // _endthreadex() completed.
3768 
3769         // Set the priority level of the current thread to the same value as
3770         // the priority level of exiting threads.
3771         // This is to ensure it will be given a fair chance to execute if
3772         // the timeout expires.
3773         hthr = GetCurrentThread();
3774         SetThreadPriority(hthr, THREAD_PRIORITY_ABOVE_NORMAL);
3775         start_time = os::javaTimeNanos();
3776         finish_time = start_time + ((jlong)EXIT_TIMEOUT * 1000000L);
3777         for (i = 0; ; ) {
3778           int portion_count = handle_count - i;
3779           if (portion_count > MAXIMUM_WAIT_OBJECTS) {
3780             portion_count = MAXIMUM_WAIT_OBJECTS;
3781           }
3782           for (j = 0; j < portion_count; ++j) {
3783             SetThreadPriority(handles[i + j], THREAD_PRIORITY_ABOVE_NORMAL);
3784           }
3785           timeout_left = (finish_time - start_time) / 1000000L;
3786           if (timeout_left < 0) {
3787             timeout_left = 0;
3788           }
3789           res = WaitForMultipleObjects(portion_count, handles + i, TRUE, timeout_left);
3790           if (res == WAIT_FAILED || res == WAIT_TIMEOUT) {
3791             warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3792                     (res == WAIT_FAILED ? "failed" : "timed out"),
3793                     GetLastError(), __FILE__, __LINE__);
3794             // Reset portion_count so we close the remaining
3795             // handles due to this error.
3796             portion_count = handle_count - i;
3797           }
3798           for (j = 0; j < portion_count; ++j) {
3799             CloseHandle(handles[i + j]);
3800           }
3801           if ((i += portion_count) >= handle_count) {
3802             break;
3803           }
3804           start_time = os::javaTimeNanos();
3805         }
3806         handle_count = 0;
3807       }
3808 
3809       LeaveCriticalSection(&crit_sect);
3810     }
3811 
3812     if (!registered &&
3813         OrderAccess::load_acquire(&process_exiting) != 0 &&
3814         process_exiting != (jint)GetCurrentThreadId()) {
3815       // Some other thread is about to call exit(), so we don't let
3816       // the current unregistered thread proceed to exit() or _endthreadex()
3817       while (true) {
3818         SuspendThread(GetCurrentThread());
3819         // Avoid busy-wait loop, if SuspendThread() failed.
3820         Sleep(EXIT_TIMEOUT);
3821       }
3822     }
3823   }
3824 
3825   // We are here if either
3826   // - there's no 'race at exit' bug on this OS release;
3827   // - initialization of the critical section failed (unlikely);
3828   // - the current thread has registered itself and left the critical section;
3829   // - the process-exiting thread has raised the flag and left the critical section.
3830   if (what == EPT_THREAD) {
3831     _endthreadex((unsigned)exit_code);
3832   } else if (what == EPT_PROCESS) {
3833     ::exit(exit_code);
3834   } else {
3835     _exit(exit_code);
3836   }
3837 
3838   // Should not reach here
3839   return exit_code;
3840 }
3841 
3842 #undef EXIT_TIMEOUT
3843 
3844 void os::win32::setmode_streams() {
3845   _setmode(_fileno(stdin), _O_BINARY);
3846   _setmode(_fileno(stdout), _O_BINARY);
3847   _setmode(_fileno(stderr), _O_BINARY);
3848 }
3849 
3850 
3851 bool os::is_debugger_attached() {
3852   return IsDebuggerPresent() ? true : false;
3853 }
3854 
3855 
3856 void os::wait_for_keypress_at_exit(void) {
3857   if (PauseAtExit) {
3858     fprintf(stderr, "Press any key to continue...\n");
3859     fgetc(stdin);
3860   }
3861 }
3862 
3863 
3864 bool os::message_box(const char* title, const char* message) {
3865   int result = MessageBox(NULL, message, title,
3866                           MB_YESNO | MB_ICONERROR | MB_SYSTEMMODAL | MB_DEFAULT_DESKTOP_ONLY);
3867   return result == IDYES;
3868 }
3869 
3870 #ifndef PRODUCT
3871 #ifndef _WIN64
3872 // Helpers to check whether NX protection is enabled
3873 int nx_exception_filter(_EXCEPTION_POINTERS *pex) {
3874   if (pex->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
3875       pex->ExceptionRecord->NumberParameters > 0 &&
3876       pex->ExceptionRecord->ExceptionInformation[0] ==
3877       EXCEPTION_INFO_EXEC_VIOLATION) {
3878     return EXCEPTION_EXECUTE_HANDLER;
3879   }
3880   return EXCEPTION_CONTINUE_SEARCH;
3881 }
3882 
3883 void nx_check_protection() {
3884   // If NX is enabled we'll get an exception calling into code on the stack
3885   char code[] = { (char)0xC3 }; // ret
3886   void *code_ptr = (void *)code;
3887   __try {
3888     __asm call code_ptr
3889   } __except(nx_exception_filter((_EXCEPTION_POINTERS*)_exception_info())) {
3890     tty->print_raw_cr("NX protection detected.");
3891   }
3892 }
3893 #endif // _WIN64
3894 #endif // PRODUCT
3895 
3896 // This is called _before_ the global arguments have been parsed
3897 void os::init(void) {
3898   _initial_pid = _getpid();
3899 
3900   init_random(1234567);
3901 
3902   win32::initialize_system_info();
3903   win32::setmode_streams();
3904   init_page_sizes((size_t) win32::vm_page_size());
3905 
3906   // This may be overridden later when argument processing is done.
3907   FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation, false);
3908 
3909   // Initialize main_process and main_thread
3910   main_process = GetCurrentProcess();  // Remember main_process is a pseudo handle
3911   if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
3912                        &main_thread, THREAD_ALL_ACCESS, false, 0)) {
3913     fatal("DuplicateHandle failed\n");
3914   }
3915   main_thread_id = (int) GetCurrentThreadId();
3916 
3917   // initialize fast thread access - only used for 32-bit
3918   win32::initialize_thread_ptr_offset();
3919 }
3920 
3921 // To install functions for atexit processing
3922 extern "C" {
3923   static void perfMemory_exit_helper() {
3924     perfMemory_exit();
3925   }
3926 }
3927 
3928 static jint initSock();
3929 
3930 // this is called _after_ the global arguments have been parsed
3931 jint os::init_2(void) {
3932   // Allocate a single page and mark it as readable for safepoint polling
3933   address polling_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READONLY);
3934   guarantee(polling_page != NULL, "Reserve Failed for polling page");
3935 
3936   address return_page  = (address)VirtualAlloc(polling_page, os::vm_page_size(), MEM_COMMIT, PAGE_READONLY);
3937   guarantee(return_page != NULL, "Commit Failed for polling page");
3938 
3939   os::set_polling_page(polling_page);
3940   log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3941 
3942   if (!UseMembar) {
3943     address mem_serialize_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READWRITE);
3944     guarantee(mem_serialize_page != NULL, "Reserve Failed for memory serialize page");
3945 
3946     return_page  = (address)VirtualAlloc(mem_serialize_page, os::vm_page_size(), MEM_COMMIT, PAGE_READWRITE);
3947     guarantee(return_page != NULL, "Commit Failed for memory serialize page");
3948 
3949     os::set_memory_serialize_page(mem_serialize_page);
3950     log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3951   }
3952 
3953   // Setup Windows Exceptions
3954 
3955   // for debugging float code generation bugs
3956   if (ForceFloatExceptions) {
3957 #ifndef  _WIN64
3958     static long fp_control_word = 0;
3959     __asm { fstcw fp_control_word }
3960     // see Intel PPro Manual, Vol. 2, p 7-16
3961     const long precision = 0x20;
3962     const long underflow = 0x10;
3963     const long overflow  = 0x08;
3964     const long zero_div  = 0x04;
3965     const long denorm    = 0x02;
3966     const long invalid   = 0x01;
3967     fp_control_word |= invalid;
3968     __asm { fldcw fp_control_word }
3969 #endif
3970   }
3971 
3972   // If stack_commit_size is 0, windows will reserve the default size,
3973   // but only commit a small portion of it.
3974   size_t stack_commit_size = align_up(ThreadStackSize*K, os::vm_page_size());
3975   size_t default_reserve_size = os::win32::default_stack_size();
3976   size_t actual_reserve_size = stack_commit_size;
3977   if (stack_commit_size < default_reserve_size) {
3978     // If stack_commit_size == 0, we want this too
3979     actual_reserve_size = default_reserve_size;
3980   }
3981 
3982   // Check minimum allowable stack size for thread creation and to initialize
3983   // the java system classes, including StackOverflowError - depends on page
3984   // size.  Add two 4K pages for compiler2 recursion in main thread.
3985   // Add in 4*BytesPerWord 4K pages to account for VM stack during
3986   // class initialization depending on 32 or 64 bit VM.
3987   size_t min_stack_allowed =
3988             (size_t)(JavaThread::stack_guard_zone_size() +
3989                      JavaThread::stack_shadow_zone_size() +
3990                      (4*BytesPerWord COMPILER2_PRESENT(+2)) * 4 * K);
3991 
3992   min_stack_allowed = align_up(min_stack_allowed, os::vm_page_size());
3993 
3994   if (actual_reserve_size < min_stack_allowed) {
3995     tty->print_cr("\nThe Java thread stack size specified is too small. "
3996                   "Specify at least %dk",
3997                   min_stack_allowed / K);
3998     return JNI_ERR;
3999   }
4000 
4001   JavaThread::set_stack_size_at_create(stack_commit_size);
4002 
4003   // Calculate theoretical max. size of Threads to guard gainst artifical
4004   // out-of-memory situations, where all available address-space has been
4005   // reserved by thread stacks.
4006   assert(actual_reserve_size != 0, "Must have a stack");
4007 
4008   // Calculate the thread limit when we should start doing Virtual Memory
4009   // banging. Currently when the threads will have used all but 200Mb of space.
4010   //
4011   // TODO: consider performing a similar calculation for commit size instead
4012   // as reserve size, since on a 64-bit platform we'll run into that more
4013   // often than running out of virtual memory space.  We can use the
4014   // lower value of the two calculations as the os_thread_limit.
4015   size_t max_address_space = ((size_t)1 << (BitsPerWord - 1)) - (200 * K * K);
4016   win32::_os_thread_limit = (intx)(max_address_space / actual_reserve_size);
4017 
4018   // at exit methods are called in the reverse order of their registration.
4019   // there is no limit to the number of functions registered. atexit does
4020   // not set errno.
4021 
4022   if (PerfAllowAtExitRegistration) {
4023     // only register atexit functions if PerfAllowAtExitRegistration is set.
4024     // atexit functions can be delayed until process exit time, which
4025     // can be problematic for embedded VM situations. Embedded VMs should
4026     // call DestroyJavaVM() to assure that VM resources are released.
4027 
4028     // note: perfMemory_exit_helper atexit function may be removed in
4029     // the future if the appropriate cleanup code can be added to the
4030     // VM_Exit VMOperation's doit method.
4031     if (atexit(perfMemory_exit_helper) != 0) {
4032       warning("os::init_2 atexit(perfMemory_exit_helper) failed");
4033     }
4034   }
4035 
4036 #ifndef _WIN64
4037   // Print something if NX is enabled (win32 on AMD64)
4038   NOT_PRODUCT(if (PrintMiscellaneous && Verbose) nx_check_protection());
4039 #endif
4040 
4041   // initialize thread priority policy
4042   prio_init();
4043 
4044   if (UseNUMA && !ForceNUMA) {
4045     UseNUMA = false; // We don't fully support this yet
4046   }
4047 
4048   if (UseNUMAInterleaving) {
4049     // first check whether this Windows OS supports VirtualAllocExNuma, if not ignore this flag
4050     bool success = numa_interleaving_init();
4051     if (!success) UseNUMAInterleaving = false;
4052   }
4053 
4054   if (initSock() != JNI_OK) {
4055     return JNI_ERR;
4056   }
4057 
4058   if (InitializeDbgHelpEarly) {
4059     SymbolEngine::recalc_search_path();
4060   }
4061 
4062   return JNI_OK;
4063 }
4064 
4065 // Mark the polling page as unreadable
4066 void os::make_polling_page_unreadable(void) {
4067   DWORD old_status;
4068   if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4069                       PAGE_NOACCESS, &old_status)) {
4070     fatal("Could not disable polling page");
4071   }
4072 }
4073 
4074 // Mark the polling page as readable
4075 void os::make_polling_page_readable(void) {
4076   DWORD old_status;
4077   if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4078                       PAGE_READONLY, &old_status)) {
4079     fatal("Could not enable polling page");
4080   }
4081 }
4082 
4083 
4084 int os::stat(const char *path, struct stat *sbuf) {
4085   char pathbuf[MAX_PATH];
4086   if (strlen(path) > MAX_PATH - 1) {
4087     errno = ENAMETOOLONG;
4088     return -1;
4089   }
4090   os::native_path(strcpy(pathbuf, path));
4091   int ret = ::stat(pathbuf, sbuf);
4092   if (sbuf != NULL && UseUTCFileTimestamp) {
4093     // Fix for 6539723.  st_mtime returned from stat() is dependent on
4094     // the system timezone and so can return different values for the
4095     // same file if/when daylight savings time changes.  This adjustment
4096     // makes sure the same timestamp is returned regardless of the TZ.
4097     //
4098     // See:
4099     // http://msdn.microsoft.com/library/
4100     //   default.asp?url=/library/en-us/sysinfo/base/
4101     //   time_zone_information_str.asp
4102     // and
4103     // http://msdn.microsoft.com/library/default.asp?url=
4104     //   /library/en-us/sysinfo/base/settimezoneinformation.asp
4105     //
4106     // NOTE: there is a insidious bug here:  If the timezone is changed
4107     // after the call to stat() but before 'GetTimeZoneInformation()', then
4108     // the adjustment we do here will be wrong and we'll return the wrong
4109     // value (which will likely end up creating an invalid class data
4110     // archive).  Absent a better API for this, or some time zone locking
4111     // mechanism, we'll have to live with this risk.
4112     TIME_ZONE_INFORMATION tz;
4113     DWORD tzid = GetTimeZoneInformation(&tz);
4114     int daylightBias =
4115       (tzid == TIME_ZONE_ID_DAYLIGHT) ?  tz.DaylightBias : tz.StandardBias;
4116     sbuf->st_mtime += (tz.Bias + daylightBias) * 60;
4117   }
4118   return ret;
4119 }
4120 
4121 
4122 #define FT2INT64(ft) \
4123   ((jlong)((jlong)(ft).dwHighDateTime << 32 | (julong)(ft).dwLowDateTime))
4124 
4125 
4126 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4127 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4128 // of a thread.
4129 //
4130 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4131 // the fast estimate available on the platform.
4132 
4133 // current_thread_cpu_time() is not optimized for Windows yet
4134 jlong os::current_thread_cpu_time() {
4135   // return user + sys since the cost is the same
4136   return os::thread_cpu_time(Thread::current(), true /* user+sys */);
4137 }
4138 
4139 jlong os::thread_cpu_time(Thread* thread) {
4140   // consistent with what current_thread_cpu_time() returns.
4141   return os::thread_cpu_time(thread, true /* user+sys */);
4142 }
4143 
4144 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4145   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4146 }
4147 
4148 jlong os::thread_cpu_time(Thread* thread, bool user_sys_cpu_time) {
4149   // This code is copy from clasic VM -> hpi::sysThreadCPUTime
4150   // If this function changes, os::is_thread_cpu_time_supported() should too
4151   FILETIME CreationTime;
4152   FILETIME ExitTime;
4153   FILETIME KernelTime;
4154   FILETIME UserTime;
4155 
4156   if (GetThreadTimes(thread->osthread()->thread_handle(), &CreationTime,
4157                       &ExitTime, &KernelTime, &UserTime) == 0) {
4158     return -1;
4159   } else if (user_sys_cpu_time) {
4160     return (FT2INT64(UserTime) + FT2INT64(KernelTime)) * 100;
4161   } else {
4162     return FT2INT64(UserTime) * 100;
4163   }
4164 }
4165 
4166 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4167   info_ptr->max_value = ALL_64_BITS;        // the max value -- all 64 bits
4168   info_ptr->may_skip_backward = false;      // GetThreadTimes returns absolute time
4169   info_ptr->may_skip_forward = false;       // GetThreadTimes returns absolute time
4170   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;   // user+system time is returned
4171 }
4172 
4173 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4174   info_ptr->max_value = ALL_64_BITS;        // the max value -- all 64 bits
4175   info_ptr->may_skip_backward = false;      // GetThreadTimes returns absolute time
4176   info_ptr->may_skip_forward = false;       // GetThreadTimes returns absolute time
4177   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;   // user+system time is returned
4178 }
4179 
4180 bool os::is_thread_cpu_time_supported() {
4181   // see os::thread_cpu_time
4182   FILETIME CreationTime;
4183   FILETIME ExitTime;
4184   FILETIME KernelTime;
4185   FILETIME UserTime;
4186 
4187   if (GetThreadTimes(GetCurrentThread(), &CreationTime, &ExitTime,
4188                       &KernelTime, &UserTime) == 0) {
4189     return false;
4190   } else {
4191     return true;
4192   }
4193 }
4194 
4195 // Windows does't provide a loadavg primitive so this is stubbed out for now.
4196 // It does have primitives (PDH API) to get CPU usage and run queue length.
4197 // "\\Processor(_Total)\\% Processor Time", "\\System\\Processor Queue Length"
4198 // If we wanted to implement loadavg on Windows, we have a few options:
4199 //
4200 // a) Query CPU usage and run queue length and "fake" an answer by
4201 //    returning the CPU usage if it's under 100%, and the run queue
4202 //    length otherwise.  It turns out that querying is pretty slow
4203 //    on Windows, on the order of 200 microseconds on a fast machine.
4204 //    Note that on the Windows the CPU usage value is the % usage
4205 //    since the last time the API was called (and the first call
4206 //    returns 100%), so we'd have to deal with that as well.
4207 //
4208 // b) Sample the "fake" answer using a sampling thread and store
4209 //    the answer in a global variable.  The call to loadavg would
4210 //    just return the value of the global, avoiding the slow query.
4211 //
4212 // c) Sample a better answer using exponential decay to smooth the
4213 //    value.  This is basically the algorithm used by UNIX kernels.
4214 //
4215 // Note that sampling thread starvation could affect both (b) and (c).
4216 int os::loadavg(double loadavg[], int nelem) {
4217   return -1;
4218 }
4219 
4220 
4221 // DontYieldALot=false by default: dutifully perform all yields as requested by JVM_Yield()
4222 bool os::dont_yield() {
4223   return DontYieldALot;
4224 }
4225 
4226 // This method is a slightly reworked copy of JDK's sysOpen
4227 // from src/windows/hpi/src/sys_api_md.c
4228 
4229 int os::open(const char *path, int oflag, int mode) {
4230   char pathbuf[MAX_PATH];
4231 
4232   if (strlen(path) > MAX_PATH - 1) {
4233     errno = ENAMETOOLONG;
4234     return -1;
4235   }
4236   os::native_path(strcpy(pathbuf, path));
4237   return ::open(pathbuf, oflag | O_BINARY | O_NOINHERIT, mode);
4238 }
4239 
4240 FILE* os::open(int fd, const char* mode) {
4241   return ::_fdopen(fd, mode);
4242 }
4243 
4244 // Is a (classpath) directory empty?
4245 bool os::dir_is_empty(const char* path) {
4246   WIN32_FIND_DATA fd;
4247   HANDLE f = FindFirstFile(path, &fd);
4248   if (f == INVALID_HANDLE_VALUE) {
4249     return true;
4250   }
4251   FindClose(f);
4252   return false;
4253 }
4254 
4255 // create binary file, rewriting existing file if required
4256 int os::create_binary_file(const char* path, bool rewrite_existing) {
4257   int oflags = _O_CREAT | _O_WRONLY | _O_BINARY;
4258   if (!rewrite_existing) {
4259     oflags |= _O_EXCL;
4260   }
4261   return ::open(path, oflags, _S_IREAD | _S_IWRITE);
4262 }
4263 
4264 // return current position of file pointer
4265 jlong os::current_file_offset(int fd) {
4266   return (jlong)::_lseeki64(fd, (__int64)0L, SEEK_CUR);
4267 }
4268 
4269 // move file pointer to the specified offset
4270 jlong os::seek_to_file_offset(int fd, jlong offset) {
4271   return (jlong)::_lseeki64(fd, (__int64)offset, SEEK_SET);
4272 }
4273 
4274 
4275 jlong os::lseek(int fd, jlong offset, int whence) {
4276   return (jlong) ::_lseeki64(fd, offset, whence);
4277 }
4278 
4279 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
4280   OVERLAPPED ov;
4281   DWORD nread;
4282   BOOL result;
4283 
4284   ZeroMemory(&ov, sizeof(ov));
4285   ov.Offset = (DWORD)offset;
4286   ov.OffsetHigh = (DWORD)(offset >> 32);
4287 
4288   HANDLE h = (HANDLE)::_get_osfhandle(fd);
4289 
4290   result = ReadFile(h, (LPVOID)buf, nBytes, &nread, &ov);
4291 
4292   return result ? nread : 0;
4293 }
4294 
4295 
4296 // This method is a slightly reworked copy of JDK's sysNativePath
4297 // from src/windows/hpi/src/path_md.c
4298 
4299 // Convert a pathname to native format.  On win32, this involves forcing all
4300 // separators to be '\\' rather than '/' (both are legal inputs, but Win95
4301 // sometimes rejects '/') and removing redundant separators.  The input path is
4302 // assumed to have been converted into the character encoding used by the local
4303 // system.  Because this might be a double-byte encoding, care is taken to
4304 // treat double-byte lead characters correctly.
4305 //
4306 // This procedure modifies the given path in place, as the result is never
4307 // longer than the original.  There is no error return; this operation always
4308 // succeeds.
4309 char * os::native_path(char *path) {
4310   char *src = path, *dst = path, *end = path;
4311   char *colon = NULL;  // If a drive specifier is found, this will
4312                        // point to the colon following the drive letter
4313 
4314   // Assumption: '/', '\\', ':', and drive letters are never lead bytes
4315   assert(((!::IsDBCSLeadByte('/')) && (!::IsDBCSLeadByte('\\'))
4316           && (!::IsDBCSLeadByte(':'))), "Illegal lead byte");
4317 
4318   // Check for leading separators
4319 #define isfilesep(c) ((c) == '/' || (c) == '\\')
4320   while (isfilesep(*src)) {
4321     src++;
4322   }
4323 
4324   if (::isalpha(*src) && !::IsDBCSLeadByte(*src) && src[1] == ':') {
4325     // Remove leading separators if followed by drive specifier.  This
4326     // hack is necessary to support file URLs containing drive
4327     // specifiers (e.g., "file://c:/path").  As a side effect,
4328     // "/c:/path" can be used as an alternative to "c:/path".
4329     *dst++ = *src++;
4330     colon = dst;
4331     *dst++ = ':';
4332     src++;
4333   } else {
4334     src = path;
4335     if (isfilesep(src[0]) && isfilesep(src[1])) {
4336       // UNC pathname: Retain first separator; leave src pointed at
4337       // second separator so that further separators will be collapsed
4338       // into the second separator.  The result will be a pathname
4339       // beginning with "\\\\" followed (most likely) by a host name.
4340       src = dst = path + 1;
4341       path[0] = '\\';     // Force first separator to '\\'
4342     }
4343   }
4344 
4345   end = dst;
4346 
4347   // Remove redundant separators from remainder of path, forcing all
4348   // separators to be '\\' rather than '/'. Also, single byte space
4349   // characters are removed from the end of the path because those
4350   // are not legal ending characters on this operating system.
4351   //
4352   while (*src != '\0') {
4353     if (isfilesep(*src)) {
4354       *dst++ = '\\'; src++;
4355       while (isfilesep(*src)) src++;
4356       if (*src == '\0') {
4357         // Check for trailing separator
4358         end = dst;
4359         if (colon == dst - 2) break;  // "z:\\"
4360         if (dst == path + 1) break;   // "\\"
4361         if (dst == path + 2 && isfilesep(path[0])) {
4362           // "\\\\" is not collapsed to "\\" because "\\\\" marks the
4363           // beginning of a UNC pathname.  Even though it is not, by
4364           // itself, a valid UNC pathname, we leave it as is in order
4365           // to be consistent with the path canonicalizer as well
4366           // as the win32 APIs, which treat this case as an invalid
4367           // UNC pathname rather than as an alias for the root
4368           // directory of the current drive.
4369           break;
4370         }
4371         end = --dst;  // Path does not denote a root directory, so
4372                       // remove trailing separator
4373         break;
4374       }
4375       end = dst;
4376     } else {
4377       if (::IsDBCSLeadByte(*src)) {  // Copy a double-byte character
4378         *dst++ = *src++;
4379         if (*src) *dst++ = *src++;
4380         end = dst;
4381       } else {  // Copy a single-byte character
4382         char c = *src++;
4383         *dst++ = c;
4384         // Space is not a legal ending character
4385         if (c != ' ') end = dst;
4386       }
4387     }
4388   }
4389 
4390   *end = '\0';
4391 
4392   // For "z:", add "." to work around a bug in the C runtime library
4393   if (colon == dst - 1) {
4394     path[2] = '.';
4395     path[3] = '\0';
4396   }
4397 
4398   return path;
4399 }
4400 
4401 // This code is a copy of JDK's sysSetLength
4402 // from src/windows/hpi/src/sys_api_md.c
4403 
4404 int os::ftruncate(int fd, jlong length) {
4405   HANDLE h = (HANDLE)::_get_osfhandle(fd);
4406   long high = (long)(length >> 32);
4407   DWORD ret;
4408 
4409   if (h == (HANDLE)(-1)) {
4410     return -1;
4411   }
4412 
4413   ret = ::SetFilePointer(h, (long)(length), &high, FILE_BEGIN);
4414   if ((ret == 0xFFFFFFFF) && (::GetLastError() != NO_ERROR)) {
4415     return -1;
4416   }
4417 
4418   if (::SetEndOfFile(h) == FALSE) {
4419     return -1;
4420   }
4421 
4422   return 0;
4423 }
4424 
4425 int os::get_fileno(FILE* fp) {
4426   return _fileno(fp);
4427 }
4428 
4429 // This code is a copy of JDK's sysSync
4430 // from src/windows/hpi/src/sys_api_md.c
4431 // except for the legacy workaround for a bug in Win 98
4432 
4433 int os::fsync(int fd) {
4434   HANDLE handle = (HANDLE)::_get_osfhandle(fd);
4435 
4436   if ((!::FlushFileBuffers(handle)) &&
4437       (GetLastError() != ERROR_ACCESS_DENIED)) {
4438     // from winerror.h
4439     return -1;
4440   }
4441   return 0;
4442 }
4443 
4444 static int nonSeekAvailable(int, long *);
4445 static int stdinAvailable(int, long *);
4446 
4447 #define S_ISCHR(mode)   (((mode) & _S_IFCHR) == _S_IFCHR)
4448 #define S_ISFIFO(mode)  (((mode) & _S_IFIFO) == _S_IFIFO)
4449 
4450 // This code is a copy of JDK's sysAvailable
4451 // from src/windows/hpi/src/sys_api_md.c
4452 
4453 int os::available(int fd, jlong *bytes) {
4454   jlong cur, end;
4455   struct _stati64 stbuf64;
4456 
4457   if (::_fstati64(fd, &stbuf64) >= 0) {
4458     int mode = stbuf64.st_mode;
4459     if (S_ISCHR(mode) || S_ISFIFO(mode)) {
4460       int ret;
4461       long lpbytes;
4462       if (fd == 0) {
4463         ret = stdinAvailable(fd, &lpbytes);
4464       } else {
4465         ret = nonSeekAvailable(fd, &lpbytes);
4466       }
4467       (*bytes) = (jlong)(lpbytes);
4468       return ret;
4469     }
4470     if ((cur = ::_lseeki64(fd, 0L, SEEK_CUR)) == -1) {
4471       return FALSE;
4472     } else if ((end = ::_lseeki64(fd, 0L, SEEK_END)) == -1) {
4473       return FALSE;
4474     } else if (::_lseeki64(fd, cur, SEEK_SET) == -1) {
4475       return FALSE;
4476     }
4477     *bytes = end - cur;
4478     return TRUE;
4479   } else {
4480     return FALSE;
4481   }
4482 }
4483 
4484 void os::flockfile(FILE* fp) {
4485   _lock_file(fp);
4486 }
4487 
4488 void os::funlockfile(FILE* fp) {
4489   _unlock_file(fp);
4490 }
4491 
4492 // This code is a copy of JDK's nonSeekAvailable
4493 // from src/windows/hpi/src/sys_api_md.c
4494 
4495 static int nonSeekAvailable(int fd, long *pbytes) {
4496   // This is used for available on non-seekable devices
4497   // (like both named and anonymous pipes, such as pipes
4498   //  connected to an exec'd process).
4499   // Standard Input is a special case.
4500   HANDLE han;
4501 
4502   if ((han = (HANDLE) ::_get_osfhandle(fd)) == (HANDLE)(-1)) {
4503     return FALSE;
4504   }
4505 
4506   if (! ::PeekNamedPipe(han, NULL, 0, NULL, (LPDWORD)pbytes, NULL)) {
4507     // PeekNamedPipe fails when at EOF.  In that case we
4508     // simply make *pbytes = 0 which is consistent with the
4509     // behavior we get on Solaris when an fd is at EOF.
4510     // The only alternative is to raise an Exception,
4511     // which isn't really warranted.
4512     //
4513     if (::GetLastError() != ERROR_BROKEN_PIPE) {
4514       return FALSE;
4515     }
4516     *pbytes = 0;
4517   }
4518   return TRUE;
4519 }
4520 
4521 #define MAX_INPUT_EVENTS 2000
4522 
4523 // This code is a copy of JDK's stdinAvailable
4524 // from src/windows/hpi/src/sys_api_md.c
4525 
4526 static int stdinAvailable(int fd, long *pbytes) {
4527   HANDLE han;
4528   DWORD numEventsRead = 0;  // Number of events read from buffer
4529   DWORD numEvents = 0;      // Number of events in buffer
4530   DWORD i = 0;              // Loop index
4531   DWORD curLength = 0;      // Position marker
4532   DWORD actualLength = 0;   // Number of bytes readable
4533   BOOL error = FALSE;       // Error holder
4534   INPUT_RECORD *lpBuffer;   // Pointer to records of input events
4535 
4536   if ((han = ::GetStdHandle(STD_INPUT_HANDLE)) == INVALID_HANDLE_VALUE) {
4537     return FALSE;
4538   }
4539 
4540   // Construct an array of input records in the console buffer
4541   error = ::GetNumberOfConsoleInputEvents(han, &numEvents);
4542   if (error == 0) {
4543     return nonSeekAvailable(fd, pbytes);
4544   }
4545 
4546   // lpBuffer must fit into 64K or else PeekConsoleInput fails
4547   if (numEvents > MAX_INPUT_EVENTS) {
4548     numEvents = MAX_INPUT_EVENTS;
4549   }
4550 
4551   lpBuffer = (INPUT_RECORD *)os::malloc(numEvents * sizeof(INPUT_RECORD), mtInternal);
4552   if (lpBuffer == NULL) {
4553     return FALSE;
4554   }
4555 
4556   error = ::PeekConsoleInput(han, lpBuffer, numEvents, &numEventsRead);
4557   if (error == 0) {
4558     os::free(lpBuffer);
4559     return FALSE;
4560   }
4561 
4562   // Examine input records for the number of bytes available
4563   for (i=0; i<numEvents; i++) {
4564     if (lpBuffer[i].EventType == KEY_EVENT) {
4565 
4566       KEY_EVENT_RECORD *keyRecord = (KEY_EVENT_RECORD *)
4567                                       &(lpBuffer[i].Event);
4568       if (keyRecord->bKeyDown == TRUE) {
4569         CHAR *keyPressed = (CHAR *) &(keyRecord->uChar);
4570         curLength++;
4571         if (*keyPressed == '\r') {
4572           actualLength = curLength;
4573         }
4574       }
4575     }
4576   }
4577 
4578   if (lpBuffer != NULL) {
4579     os::free(lpBuffer);
4580   }
4581 
4582   *pbytes = (long) actualLength;
4583   return TRUE;
4584 }
4585 
4586 // Map a block of memory.
4587 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4588                         char *addr, size_t bytes, bool read_only,
4589                         bool allow_exec) {
4590   HANDLE hFile;
4591   char* base;
4592 
4593   hFile = CreateFile(file_name, GENERIC_READ, FILE_SHARE_READ, NULL,
4594                      OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
4595   if (hFile == NULL) {
4596     log_info(os)("CreateFile() failed: GetLastError->%ld.", GetLastError());
4597     return NULL;
4598   }
4599 
4600   if (allow_exec) {
4601     // CreateFileMapping/MapViewOfFileEx can't map executable memory
4602     // unless it comes from a PE image (which the shared archive is not.)
4603     // Even VirtualProtect refuses to give execute access to mapped memory
4604     // that was not previously executable.
4605     //
4606     // Instead, stick the executable region in anonymous memory.  Yuck.
4607     // Penalty is that ~4 pages will not be shareable - in the future
4608     // we might consider DLLizing the shared archive with a proper PE
4609     // header so that mapping executable + sharing is possible.
4610 
4611     base = (char*) VirtualAlloc(addr, bytes, MEM_COMMIT | MEM_RESERVE,
4612                                 PAGE_READWRITE);
4613     if (base == NULL) {
4614       log_info(os)("VirtualAlloc() failed: GetLastError->%ld.", GetLastError());
4615       CloseHandle(hFile);
4616       return NULL;
4617     }
4618 
4619     DWORD bytes_read;
4620     OVERLAPPED overlapped;
4621     overlapped.Offset = (DWORD)file_offset;
4622     overlapped.OffsetHigh = 0;
4623     overlapped.hEvent = NULL;
4624     // ReadFile guarantees that if the return value is true, the requested
4625     // number of bytes were read before returning.
4626     bool res = ReadFile(hFile, base, (DWORD)bytes, &bytes_read, &overlapped) != 0;
4627     if (!res) {
4628       log_info(os)("ReadFile() failed: GetLastError->%ld.", GetLastError());
4629       release_memory(base, bytes);
4630       CloseHandle(hFile);
4631       return NULL;
4632     }
4633   } else {
4634     HANDLE hMap = CreateFileMapping(hFile, NULL, PAGE_WRITECOPY, 0, 0,
4635                                     NULL /* file_name */);
4636     if (hMap == NULL) {
4637       log_info(os)("CreateFileMapping() failed: GetLastError->%ld.", GetLastError());
4638       CloseHandle(hFile);
4639       return NULL;
4640     }
4641 
4642     DWORD access = read_only ? FILE_MAP_READ : FILE_MAP_COPY;
4643     base = (char*)MapViewOfFileEx(hMap, access, 0, (DWORD)file_offset,
4644                                   (DWORD)bytes, addr);
4645     if (base == NULL) {
4646       log_info(os)("MapViewOfFileEx() failed: GetLastError->%ld.", GetLastError());
4647       CloseHandle(hMap);
4648       CloseHandle(hFile);
4649       return NULL;
4650     }
4651 
4652     if (CloseHandle(hMap) == 0) {
4653       log_info(os)("CloseHandle(hMap) failed: GetLastError->%ld.", GetLastError());
4654       CloseHandle(hFile);
4655       return base;
4656     }
4657   }
4658 
4659   if (allow_exec) {
4660     DWORD old_protect;
4661     DWORD exec_access = read_only ? PAGE_EXECUTE_READ : PAGE_EXECUTE_READWRITE;
4662     bool res = VirtualProtect(base, bytes, exec_access, &old_protect) != 0;
4663 
4664     if (!res) {
4665       log_info(os)("VirtualProtect() failed: GetLastError->%ld.", GetLastError());
4666       // Don't consider this a hard error, on IA32 even if the
4667       // VirtualProtect fails, we should still be able to execute
4668       CloseHandle(hFile);
4669       return base;
4670     }
4671   }
4672 
4673   if (CloseHandle(hFile) == 0) {
4674     log_info(os)("CloseHandle(hFile) failed: GetLastError->%ld.", GetLastError());
4675     return base;
4676   }
4677 
4678   return base;
4679 }
4680 
4681 
4682 // Remap a block of memory.
4683 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4684                           char *addr, size_t bytes, bool read_only,
4685                           bool allow_exec) {
4686   // This OS does not allow existing memory maps to be remapped so we
4687   // have to unmap the memory before we remap it.
4688   if (!os::unmap_memory(addr, bytes)) {
4689     return NULL;
4690   }
4691 
4692   // There is a very small theoretical window between the unmap_memory()
4693   // call above and the map_memory() call below where a thread in native
4694   // code may be able to access an address that is no longer mapped.
4695 
4696   return os::map_memory(fd, file_name, file_offset, addr, bytes,
4697                         read_only, allow_exec);
4698 }
4699 
4700 
4701 // Unmap a block of memory.
4702 // Returns true=success, otherwise false.
4703 
4704 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4705   MEMORY_BASIC_INFORMATION mem_info;
4706   if (VirtualQuery(addr, &mem_info, sizeof(mem_info)) == 0) {
4707     log_info(os)("VirtualQuery() failed: GetLastError->%ld.", GetLastError());
4708     return false;
4709   }
4710 
4711   // Executable memory was not mapped using CreateFileMapping/MapViewOfFileEx.
4712   // Instead, executable region was allocated using VirtualAlloc(). See
4713   // pd_map_memory() above.
4714   //
4715   // The following flags should match the 'exec_access' flages used for
4716   // VirtualProtect() in pd_map_memory().
4717   if (mem_info.Protect == PAGE_EXECUTE_READ ||
4718       mem_info.Protect == PAGE_EXECUTE_READWRITE) {
4719     return pd_release_memory(addr, bytes);
4720   }
4721 
4722   BOOL result = UnmapViewOfFile(addr);
4723   if (result == 0) {
4724     log_info(os)("UnmapViewOfFile() failed: GetLastError->%ld.", GetLastError());
4725     return false;
4726   }
4727   return true;
4728 }
4729 
4730 void os::pause() {
4731   char filename[MAX_PATH];
4732   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4733     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4734   } else {
4735     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4736   }
4737 
4738   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4739   if (fd != -1) {
4740     struct stat buf;
4741     ::close(fd);
4742     while (::stat(filename, &buf) == 0) {
4743       Sleep(100);
4744     }
4745   } else {
4746     jio_fprintf(stderr,
4747                 "Could not open pause file '%s', continuing immediately.\n", filename);
4748   }
4749 }
4750 
4751 Thread* os::ThreadCrashProtection::_protected_thread = NULL;
4752 os::ThreadCrashProtection* os::ThreadCrashProtection::_crash_protection = NULL;
4753 volatile intptr_t os::ThreadCrashProtection::_crash_mux = 0;
4754 
4755 os::ThreadCrashProtection::ThreadCrashProtection() {
4756 }
4757 
4758 // See the caveats for this class in os_windows.hpp
4759 // Protects the callback call so that raised OS EXCEPTIONS causes a jump back
4760 // into this method and returns false. If no OS EXCEPTION was raised, returns
4761 // true.
4762 // The callback is supposed to provide the method that should be protected.
4763 //
4764 bool os::ThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
4765 
4766   Thread::muxAcquire(&_crash_mux, "CrashProtection");
4767 
4768   _protected_thread = Thread::current_or_null();
4769   assert(_protected_thread != NULL, "Cannot crash protect a NULL thread");
4770 
4771   bool success = true;
4772   __try {
4773     _crash_protection = this;
4774     cb.call();
4775   } __except(EXCEPTION_EXECUTE_HANDLER) {
4776     // only for protection, nothing to do
4777     success = false;
4778   }
4779   _crash_protection = NULL;
4780   _protected_thread = NULL;
4781   Thread::muxRelease(&_crash_mux);
4782   return success;
4783 }
4784 
4785 // An Event wraps a win32 "CreateEvent" kernel handle.
4786 //
4787 // We have a number of choices regarding "CreateEvent" win32 handle leakage:
4788 //
4789 // 1:  When a thread dies return the Event to the EventFreeList, clear the ParkHandle
4790 //     field, and call CloseHandle() on the win32 event handle.  Unpark() would
4791 //     need to be modified to tolerate finding a NULL (invalid) win32 event handle.
4792 //     In addition, an unpark() operation might fetch the handle field, but the
4793 //     event could recycle between the fetch and the SetEvent() operation.
4794 //     SetEvent() would either fail because the handle was invalid, or inadvertently work,
4795 //     as the win32 handle value had been recycled.  In an ideal world calling SetEvent()
4796 //     on an stale but recycled handle would be harmless, but in practice this might
4797 //     confuse other non-Sun code, so it's not a viable approach.
4798 //
4799 // 2:  Once a win32 event handle is associated with an Event, it remains associated
4800 //     with the Event.  The event handle is never closed.  This could be construed
4801 //     as handle leakage, but only up to the maximum # of threads that have been extant
4802 //     at any one time.  This shouldn't be an issue, as windows platforms typically
4803 //     permit a process to have hundreds of thousands of open handles.
4804 //
4805 // 3:  Same as (1), but periodically, at stop-the-world time, rundown the EventFreeList
4806 //     and release unused handles.
4807 //
4808 // 4:  Add a CRITICAL_SECTION to the Event to protect LD+SetEvent from LD;ST(null);CloseHandle.
4809 //     It's not clear, however, that we wouldn't be trading one type of leak for another.
4810 //
4811 // 5.  Use an RCU-like mechanism (Read-Copy Update).
4812 //     Or perhaps something similar to Maged Michael's "Hazard pointers".
4813 //
4814 // We use (2).
4815 //
4816 // TODO-FIXME:
4817 // 1.  Reconcile Doug's JSR166 j.u.c park-unpark with the objectmonitor implementation.
4818 // 2.  Consider wrapping the WaitForSingleObject(Ex) calls in SEH try/finally blocks
4819 //     to recover from (or at least detect) the dreaded Windows 841176 bug.
4820 // 3.  Collapse the interrupt_event, the JSR166 parker event, and the objectmonitor ParkEvent
4821 //     into a single win32 CreateEvent() handle.
4822 //
4823 // Assumption:
4824 //    Only one parker can exist on an event, which is why we allocate
4825 //    them per-thread. Multiple unparkers can coexist.
4826 //
4827 // _Event transitions in park()
4828 //   -1 => -1 : illegal
4829 //    1 =>  0 : pass - return immediately
4830 //    0 => -1 : block; then set _Event to 0 before returning
4831 //
4832 // _Event transitions in unpark()
4833 //    0 => 1 : just return
4834 //    1 => 1 : just return
4835 //   -1 => either 0 or 1; must signal target thread
4836 //         That is, we can safely transition _Event from -1 to either
4837 //         0 or 1.
4838 //
4839 // _Event serves as a restricted-range semaphore.
4840 //   -1 : thread is blocked, i.e. there is a waiter
4841 //    0 : neutral: thread is running or ready,
4842 //        could have been signaled after a wait started
4843 //    1 : signaled - thread is running or ready
4844 //
4845 // Another possible encoding of _Event would be with
4846 // explicit "PARKED" == 01b and "SIGNALED" == 10b bits.
4847 //
4848 
4849 int os::PlatformEvent::park(jlong Millis) {
4850   // Transitions for _Event:
4851   //   -1 => -1 : illegal
4852   //    1 =>  0 : pass - return immediately
4853   //    0 => -1 : block; then set _Event to 0 before returning
4854 
4855   guarantee(_ParkHandle != NULL , "Invariant");
4856   guarantee(Millis > 0          , "Invariant");
4857 
4858   // CONSIDER: defer assigning a CreateEvent() handle to the Event until
4859   // the initial park() operation.
4860   // Consider: use atomic decrement instead of CAS-loop
4861 
4862   int v;
4863   for (;;) {
4864     v = _Event;
4865     if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4866   }
4867   guarantee((v == 0) || (v == 1), "invariant");
4868   if (v != 0) return OS_OK;
4869 
4870   // Do this the hard way by blocking ...
4871   // TODO: consider a brief spin here, gated on the success of recent
4872   // spin attempts by this thread.
4873   //
4874   // We decompose long timeouts into series of shorter timed waits.
4875   // Evidently large timo values passed in WaitForSingleObject() are problematic on some
4876   // versions of Windows.  See EventWait() for details.  This may be superstition.  Or not.
4877   // We trust the WAIT_TIMEOUT indication and don't track the elapsed wait time
4878   // with os::javaTimeNanos().  Furthermore, we assume that spurious returns from
4879   // ::WaitForSingleObject() caused by latent ::setEvent() operations will tend
4880   // to happen early in the wait interval.  Specifically, after a spurious wakeup (rv ==
4881   // WAIT_OBJECT_0 but _Event is still < 0) we don't bother to recompute Millis to compensate
4882   // for the already waited time.  This policy does not admit any new outcomes.
4883   // In the future, however, we might want to track the accumulated wait time and
4884   // adjust Millis accordingly if we encounter a spurious wakeup.
4885 
4886   const int MAXTIMEOUT = 0x10000000;
4887   DWORD rv = WAIT_TIMEOUT;
4888   while (_Event < 0 && Millis > 0) {
4889     DWORD prd = Millis;     // set prd = MAX (Millis, MAXTIMEOUT)
4890     if (Millis > MAXTIMEOUT) {
4891       prd = MAXTIMEOUT;
4892     }
4893     rv = ::WaitForSingleObject(_ParkHandle, prd);
4894     assert(rv == WAIT_OBJECT_0 || rv == WAIT_TIMEOUT, "WaitForSingleObject failed");
4895     if (rv == WAIT_TIMEOUT) {
4896       Millis -= prd;
4897     }
4898   }
4899   v = _Event;
4900   _Event = 0;
4901   // see comment at end of os::PlatformEvent::park() below:
4902   OrderAccess::fence();
4903   // If we encounter a nearly simultanous timeout expiry and unpark()
4904   // we return OS_OK indicating we awoke via unpark().
4905   // Implementor's license -- returning OS_TIMEOUT would be equally valid, however.
4906   return (v >= 0) ? OS_OK : OS_TIMEOUT;
4907 }
4908 
4909 void os::PlatformEvent::park() {
4910   // Transitions for _Event:
4911   //   -1 => -1 : illegal
4912   //    1 =>  0 : pass - return immediately
4913   //    0 => -1 : block; then set _Event to 0 before returning
4914 
4915   guarantee(_ParkHandle != NULL, "Invariant");
4916   // Invariant: Only the thread associated with the Event/PlatformEvent
4917   // may call park().
4918   // Consider: use atomic decrement instead of CAS-loop
4919   int v;
4920   for (;;) {
4921     v = _Event;
4922     if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4923   }
4924   guarantee((v == 0) || (v == 1), "invariant");
4925   if (v != 0) return;
4926 
4927   // Do this the hard way by blocking ...
4928   // TODO: consider a brief spin here, gated on the success of recent
4929   // spin attempts by this thread.
4930   while (_Event < 0) {
4931     DWORD rv = ::WaitForSingleObject(_ParkHandle, INFINITE);
4932     assert(rv == WAIT_OBJECT_0, "WaitForSingleObject failed");
4933   }
4934 
4935   // Usually we'll find _Event == 0 at this point, but as
4936   // an optional optimization we clear it, just in case can
4937   // multiple unpark() operations drove _Event up to 1.
4938   _Event = 0;
4939   OrderAccess::fence();
4940   guarantee(_Event >= 0, "invariant");
4941 }
4942 
4943 void os::PlatformEvent::unpark() {
4944   guarantee(_ParkHandle != NULL, "Invariant");
4945 
4946   // Transitions for _Event:
4947   //    0 => 1 : just return
4948   //    1 => 1 : just return
4949   //   -1 => either 0 or 1; must signal target thread
4950   //         That is, we can safely transition _Event from -1 to either
4951   //         0 or 1.
4952   // See also: "Semaphores in Plan 9" by Mullender & Cox
4953   //
4954   // Note: Forcing a transition from "-1" to "1" on an unpark() means
4955   // that it will take two back-to-back park() calls for the owning
4956   // thread to block. This has the benefit of forcing a spurious return
4957   // from the first park() call after an unpark() call which will help
4958   // shake out uses of park() and unpark() without condition variables.
4959 
4960   if (Atomic::xchg(1, &_Event) >= 0) return;
4961 
4962   ::SetEvent(_ParkHandle);
4963 }
4964 
4965 
4966 // JSR166
4967 // -------------------------------------------------------
4968 
4969 // The Windows implementation of Park is very straightforward: Basic
4970 // operations on Win32 Events turn out to have the right semantics to
4971 // use them directly. We opportunistically resuse the event inherited
4972 // from Monitor.
4973 
4974 void Parker::park(bool isAbsolute, jlong time) {
4975   guarantee(_ParkEvent != NULL, "invariant");
4976   // First, demultiplex/decode time arguments
4977   if (time < 0) { // don't wait
4978     return;
4979   } else if (time == 0 && !isAbsolute) {
4980     time = INFINITE;
4981   } else if (isAbsolute) {
4982     time -= os::javaTimeMillis(); // convert to relative time
4983     if (time <= 0) {  // already elapsed
4984       return;
4985     }
4986   } else { // relative
4987     time /= 1000000;  // Must coarsen from nanos to millis
4988     if (time == 0) {  // Wait for the minimal time unit if zero
4989       time = 1;
4990     }
4991   }
4992 
4993   JavaThread* thread = JavaThread::current();
4994 
4995   // Don't wait if interrupted or already triggered
4996   if (Thread::is_interrupted(thread, false) ||
4997       WaitForSingleObject(_ParkEvent, 0) == WAIT_OBJECT_0) {
4998     ResetEvent(_ParkEvent);
4999     return;
5000   } else {
5001     ThreadBlockInVM tbivm(thread);
5002     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
5003     thread->set_suspend_equivalent();
5004 
5005     WaitForSingleObject(_ParkEvent, time);
5006     ResetEvent(_ParkEvent);
5007 
5008     // If externally suspended while waiting, re-suspend
5009     if (thread->handle_special_suspend_equivalent_condition()) {
5010       thread->java_suspend_self();
5011     }
5012   }
5013 }
5014 
5015 void Parker::unpark() {
5016   guarantee(_ParkEvent != NULL, "invariant");
5017   SetEvent(_ParkEvent);
5018 }
5019 
5020 // Run the specified command in a separate process. Return its exit value,
5021 // or -1 on failure (e.g. can't create a new process).
5022 int os::fork_and_exec(char* cmd) {
5023   STARTUPINFO si;
5024   PROCESS_INFORMATION pi;
5025   DWORD exit_code;
5026 
5027   char * cmd_string;
5028   char * cmd_prefix = "cmd /C ";
5029   size_t len = strlen(cmd) + strlen(cmd_prefix) + 1;
5030   cmd_string = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtInternal);
5031   if (cmd_string == NULL) {
5032     return -1;
5033   }
5034   cmd_string[0] = '\0';
5035   strcat(cmd_string, cmd_prefix);
5036   strcat(cmd_string, cmd);
5037 
5038   // now replace all '\n' with '&'
5039   char * substring = cmd_string;
5040   while ((substring = strchr(substring, '\n')) != NULL) {
5041     substring[0] = '&';
5042     substring++;
5043   }
5044   memset(&si, 0, sizeof(si));
5045   si.cb = sizeof(si);
5046   memset(&pi, 0, sizeof(pi));
5047   BOOL rslt = CreateProcess(NULL,   // executable name - use command line
5048                             cmd_string,    // command line
5049                             NULL,   // process security attribute
5050                             NULL,   // thread security attribute
5051                             TRUE,   // inherits system handles
5052                             0,      // no creation flags
5053                             NULL,   // use parent's environment block
5054                             NULL,   // use parent's starting directory
5055                             &si,    // (in) startup information
5056                             &pi);   // (out) process information
5057 
5058   if (rslt) {
5059     // Wait until child process exits.
5060     WaitForSingleObject(pi.hProcess, INFINITE);
5061 
5062     GetExitCodeProcess(pi.hProcess, &exit_code);
5063 
5064     // Close process and thread handles.
5065     CloseHandle(pi.hProcess);
5066     CloseHandle(pi.hThread);
5067   } else {
5068     exit_code = -1;
5069   }
5070 
5071   FREE_C_HEAP_ARRAY(char, cmd_string);
5072   return (int)exit_code;
5073 }
5074 
5075 bool os::find(address addr, outputStream* st) {
5076   int offset = -1;
5077   bool result = false;
5078   char buf[256];
5079   if (os::dll_address_to_library_name(addr, buf, sizeof(buf), &offset)) {
5080     st->print(PTR_FORMAT " ", addr);
5081     if (strlen(buf) < sizeof(buf) - 1) {
5082       char* p = strrchr(buf, '\\');
5083       if (p) {
5084         st->print("%s", p + 1);
5085       } else {
5086         st->print("%s", buf);
5087       }
5088     } else {
5089         // The library name is probably truncated. Let's omit the library name.
5090         // See also JDK-8147512.
5091     }
5092     if (os::dll_address_to_function_name(addr, buf, sizeof(buf), &offset)) {
5093       st->print("::%s + 0x%x", buf, offset);
5094     }
5095     st->cr();
5096     result = true;
5097   }
5098   return result;
5099 }
5100 
5101 LONG WINAPI os::win32::serialize_fault_filter(struct _EXCEPTION_POINTERS* e) {
5102   DWORD exception_code = e->ExceptionRecord->ExceptionCode;
5103 
5104   if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
5105     JavaThread* thread = JavaThread::current();
5106     PEXCEPTION_RECORD exceptionRecord = e->ExceptionRecord;
5107     address addr = (address) exceptionRecord->ExceptionInformation[1];
5108 
5109     if (os::is_memory_serialize_page(thread, addr)) {
5110       return EXCEPTION_CONTINUE_EXECUTION;
5111     }
5112   }
5113 
5114   return EXCEPTION_CONTINUE_SEARCH;
5115 }
5116 
5117 // We don't build a headless jre for Windows
5118 bool os::is_headless_jre() { return false; }
5119 
5120 static jint initSock() {
5121   WSADATA wsadata;
5122 
5123   if (WSAStartup(MAKEWORD(2,2), &wsadata) != 0) {
5124     jio_fprintf(stderr, "Could not initialize Winsock (error: %d)\n",
5125                 ::GetLastError());
5126     return JNI_ERR;
5127   }
5128   return JNI_OK;
5129 }
5130 
5131 struct hostent* os::get_host_by_name(char* name) {
5132   return (struct hostent*)gethostbyname(name);
5133 }
5134 
5135 int os::socket_close(int fd) {
5136   return ::closesocket(fd);
5137 }
5138 
5139 int os::socket(int domain, int type, int protocol) {
5140   return ::socket(domain, type, protocol);
5141 }
5142 
5143 int os::connect(int fd, struct sockaddr* him, socklen_t len) {
5144   return ::connect(fd, him, len);
5145 }
5146 
5147 int os::recv(int fd, char* buf, size_t nBytes, uint flags) {
5148   return ::recv(fd, buf, (int)nBytes, flags);
5149 }
5150 
5151 int os::send(int fd, char* buf, size_t nBytes, uint flags) {
5152   return ::send(fd, buf, (int)nBytes, flags);
5153 }
5154 
5155 int os::raw_send(int fd, char* buf, size_t nBytes, uint flags) {
5156   return ::send(fd, buf, (int)nBytes, flags);
5157 }
5158 
5159 // WINDOWS CONTEXT Flags for THREAD_SAMPLING
5160 #if defined(IA32)
5161   #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS)
5162 #elif defined (AMD64)
5163   #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT)
5164 #endif
5165 
5166 // returns true if thread could be suspended,
5167 // false otherwise
5168 static bool do_suspend(HANDLE* h) {
5169   if (h != NULL) {
5170     if (SuspendThread(*h) != ~0) {
5171       return true;
5172     }
5173   }
5174   return false;
5175 }
5176 
5177 // resume the thread
5178 // calling resume on an active thread is a no-op
5179 static void do_resume(HANDLE* h) {
5180   if (h != NULL) {
5181     ResumeThread(*h);
5182   }
5183 }
5184 
5185 // retrieve a suspend/resume context capable handle
5186 // from the tid. Caller validates handle return value.
5187 void get_thread_handle_for_extended_context(HANDLE* h,
5188                                             OSThread::thread_id_t tid) {
5189   if (h != NULL) {
5190     *h = OpenThread(THREAD_SUSPEND_RESUME | THREAD_GET_CONTEXT | THREAD_QUERY_INFORMATION, FALSE, tid);
5191   }
5192 }
5193 
5194 // Thread sampling implementation
5195 //
5196 void os::SuspendedThreadTask::internal_do_task() {
5197   CONTEXT    ctxt;
5198   HANDLE     h = NULL;
5199 
5200   // get context capable handle for thread
5201   get_thread_handle_for_extended_context(&h, _thread->osthread()->thread_id());
5202 
5203   // sanity
5204   if (h == NULL || h == INVALID_HANDLE_VALUE) {
5205     return;
5206   }
5207 
5208   // suspend the thread
5209   if (do_suspend(&h)) {
5210     ctxt.ContextFlags = sampling_context_flags;
5211     // get thread context
5212     GetThreadContext(h, &ctxt);
5213     SuspendedThreadTaskContext context(_thread, &ctxt);
5214     // pass context to Thread Sampling impl
5215     do_task(context);
5216     // resume thread
5217     do_resume(&h);
5218   }
5219 
5220   // close handle
5221   CloseHandle(h);
5222 }
5223 
5224 bool os::start_debugging(char *buf, int buflen) {
5225   int len = (int)strlen(buf);
5226   char *p = &buf[len];
5227 
5228   jio_snprintf(p, buflen-len,
5229              "\n\n"
5230              "Do you want to debug the problem?\n\n"
5231              "To debug, attach Visual Studio to process %d; then switch to thread 0x%x\n"
5232              "Select 'Yes' to launch Visual Studio automatically (PATH must include msdev)\n"
5233              "Otherwise, select 'No' to abort...",
5234              os::current_process_id(), os::current_thread_id());
5235 
5236   bool yes = os::message_box("Unexpected Error", buf);
5237 
5238   if (yes) {
5239     // os::breakpoint() calls DebugBreak(), which causes a breakpoint
5240     // exception. If VM is running inside a debugger, the debugger will
5241     // catch the exception. Otherwise, the breakpoint exception will reach
5242     // the default windows exception handler, which can spawn a debugger and
5243     // automatically attach to the dying VM.
5244     os::breakpoint();
5245     yes = false;
5246   }
5247   return yes;
5248 }
5249 
5250 void* os::get_default_process_handle() {
5251   return (void*)GetModuleHandle(NULL);
5252 }
5253 
5254 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
5255 // which is used to find statically linked in agents.
5256 // Additionally for windows, takes into account __stdcall names.
5257 // Parameters:
5258 //            sym_name: Symbol in library we are looking for
5259 //            lib_name: Name of library to look in, NULL for shared libs.
5260 //            is_absolute_path == true if lib_name is absolute path to agent
5261 //                                     such as "C:/a/b/L.dll"
5262 //            == false if only the base name of the library is passed in
5263 //               such as "L"
5264 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
5265                                     bool is_absolute_path) {
5266   char *agent_entry_name;
5267   size_t len;
5268   size_t name_len;
5269   size_t prefix_len = strlen(JNI_LIB_PREFIX);
5270   size_t suffix_len = strlen(JNI_LIB_SUFFIX);
5271   const char *start;
5272 
5273   if (lib_name != NULL) {
5274     len = name_len = strlen(lib_name);
5275     if (is_absolute_path) {
5276       // Need to strip path, prefix and suffix
5277       if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
5278         lib_name = ++start;
5279       } else {
5280         // Need to check for drive prefix
5281         if ((start = strchr(lib_name, ':')) != NULL) {
5282           lib_name = ++start;
5283         }
5284       }
5285       if (len <= (prefix_len + suffix_len)) {
5286         return NULL;
5287       }
5288       lib_name += prefix_len;
5289       name_len = strlen(lib_name) - suffix_len;
5290     }
5291   }
5292   len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
5293   agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
5294   if (agent_entry_name == NULL) {
5295     return NULL;
5296   }
5297   if (lib_name != NULL) {
5298     const char *p = strrchr(sym_name, '@');
5299     if (p != NULL && p != sym_name) {
5300       // sym_name == _Agent_OnLoad@XX
5301       strncpy(agent_entry_name, sym_name, (p - sym_name));
5302       agent_entry_name[(p-sym_name)] = '\0';
5303       // agent_entry_name == _Agent_OnLoad
5304       strcat(agent_entry_name, "_");
5305       strncat(agent_entry_name, lib_name, name_len);
5306       strcat(agent_entry_name, p);
5307       // agent_entry_name == _Agent_OnLoad_lib_name@XX
5308     } else {
5309       strcpy(agent_entry_name, sym_name);
5310       strcat(agent_entry_name, "_");
5311       strncat(agent_entry_name, lib_name, name_len);
5312     }
5313   } else {
5314     strcpy(agent_entry_name, sym_name);
5315   }
5316   return agent_entry_name;
5317 }
5318 
5319 #ifndef PRODUCT
5320 
5321 // test the code path in reserve_memory_special() that tries to allocate memory in a single
5322 // contiguous memory block at a particular address.
5323 // The test first tries to find a good approximate address to allocate at by using the same
5324 // method to allocate some memory at any address. The test then tries to allocate memory in
5325 // the vicinity (not directly after it to avoid possible by-chance use of that location)
5326 // This is of course only some dodgy assumption, there is no guarantee that the vicinity of
5327 // the previously allocated memory is available for allocation. The only actual failure
5328 // that is reported is when the test tries to allocate at a particular location but gets a
5329 // different valid one. A NULL return value at this point is not considered an error but may
5330 // be legitimate.
5331 // If -XX:+VerboseInternalVMTests is enabled, print some explanatory messages.
5332 void TestReserveMemorySpecial_test() {
5333   if (!UseLargePages) {
5334     if (VerboseInternalVMTests) {
5335       tty->print("Skipping test because large pages are disabled");
5336     }
5337     return;
5338   }
5339   // save current value of globals
5340   bool old_use_large_pages_individual_allocation = UseLargePagesIndividualAllocation;
5341   bool old_use_numa_interleaving = UseNUMAInterleaving;
5342 
5343   // set globals to make sure we hit the correct code path
5344   UseLargePagesIndividualAllocation = UseNUMAInterleaving = false;
5345 
5346   // do an allocation at an address selected by the OS to get a good one.
5347   const size_t large_allocation_size = os::large_page_size() * 4;
5348   char* result = os::reserve_memory_special(large_allocation_size, os::large_page_size(), NULL, false);
5349   if (result == NULL) {
5350     if (VerboseInternalVMTests) {
5351       tty->print("Failed to allocate control block with size " SIZE_FORMAT ". Skipping remainder of test.",
5352                           large_allocation_size);
5353     }
5354   } else {
5355     os::release_memory_special(result, large_allocation_size);
5356 
5357     // allocate another page within the recently allocated memory area which seems to be a good location. At least
5358     // we managed to get it once.
5359     const size_t expected_allocation_size = os::large_page_size();
5360     char* expected_location = result + os::large_page_size();
5361     char* actual_location = os::reserve_memory_special(expected_allocation_size, os::large_page_size(), expected_location, false);
5362     if (actual_location == NULL) {
5363       if (VerboseInternalVMTests) {
5364         tty->print("Failed to allocate any memory at " PTR_FORMAT " size " SIZE_FORMAT ". Skipping remainder of test.",
5365                             expected_location, large_allocation_size);
5366       }
5367     } else {
5368       // release memory
5369       os::release_memory_special(actual_location, expected_allocation_size);
5370       // only now check, after releasing any memory to avoid any leaks.
5371       assert(actual_location == expected_location,
5372              "Failed to allocate memory at requested location " PTR_FORMAT " of size " SIZE_FORMAT ", is " PTR_FORMAT " instead",
5373              expected_location, expected_allocation_size, actual_location);
5374     }
5375   }
5376 
5377   // restore globals
5378   UseLargePagesIndividualAllocation = old_use_large_pages_individual_allocation;
5379   UseNUMAInterleaving = old_use_numa_interleaving;
5380 }
5381 #endif // PRODUCT
5382 
5383 /*
5384   All the defined signal names for Windows.
5385 
5386   NOTE that not all of these names are accepted by FindSignal!
5387 
5388   For various reasons some of these may be rejected at runtime.
5389 
5390   Here are the names currently accepted by a user of sun.misc.Signal with
5391   1.4.1 (ignoring potential interaction with use of chaining, etc):
5392 
5393      (LIST TBD)
5394 
5395 */
5396 int os::get_signal_number(const char* name) {
5397   static const struct {
5398     char* name;
5399     int   number;
5400   } siglabels [] =
5401     // derived from version 6.0 VC98/include/signal.h
5402   {"ABRT",      SIGABRT,        // abnormal termination triggered by abort cl
5403   "FPE",        SIGFPE,         // floating point exception
5404   "SEGV",       SIGSEGV,        // segment violation
5405   "INT",        SIGINT,         // interrupt
5406   "TERM",       SIGTERM,        // software term signal from kill
5407   "BREAK",      SIGBREAK,       // Ctrl-Break sequence
5408   "ILL",        SIGILL};        // illegal instruction
5409   for (unsigned i = 0; i < ARRAY_SIZE(siglabels); ++i) {
5410     if (strcmp(name, siglabels[i].name) == 0) {
5411       return siglabels[i].number;
5412     }
5413   }
5414   return -1;
5415 }
5416 
5417 // Fast current thread access
5418 
5419 int os::win32::_thread_ptr_offset = 0;
5420 
5421 static void call_wrapper_dummy() {}
5422 
5423 // We need to call the os_exception_wrapper once so that it sets
5424 // up the offset from FS of the thread pointer.
5425 void os::win32::initialize_thread_ptr_offset() {
5426   os::os_exception_wrapper((java_call_t)call_wrapper_dummy,
5427                            NULL, NULL, NULL, NULL);
5428 }