1 /*
   2  * Copyright (c) 1999, 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 // no precompiled headers
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "classfile/vmSymbols.hpp"
  29 #include "code/icBuffer.hpp"
  30 #include "code/vtableStubs.hpp"
  31 #include "compiler/compileBroker.hpp"
  32 #include "compiler/disassembler.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "jvm_bsd.h"
  35 #include "logging/log.hpp"
  36 #include "memory/allocation.inline.hpp"
  37 #include "memory/filemap.hpp"
  38 #include "oops/oop.inline.hpp"
  39 #include "os_bsd.inline.hpp"
  40 #include "os_share_bsd.hpp"
  41 #include "prims/jniFastGetField.hpp"
  42 #include "prims/jvm.h"
  43 #include "prims/jvm_misc.hpp"
  44 #include "runtime/arguments.hpp"
  45 #include "runtime/atomic.hpp"
  46 #include "runtime/extendedPC.hpp"
  47 #include "runtime/globals.hpp"
  48 #include "runtime/interfaceSupport.hpp"
  49 #include "runtime/java.hpp"
  50 #include "runtime/javaCalls.hpp"
  51 #include "runtime/mutexLocker.hpp"
  52 #include "runtime/objectMonitor.hpp"
  53 #include "runtime/orderAccess.inline.hpp"
  54 #include "runtime/osThread.hpp"
  55 #include "runtime/perfMemory.hpp"
  56 #include "runtime/sharedRuntime.hpp"
  57 #include "runtime/statSampler.hpp"
  58 #include "runtime/stubRoutines.hpp"
  59 #include "runtime/thread.inline.hpp"
  60 #include "runtime/threadCritical.hpp"
  61 #include "runtime/timer.hpp"
  62 #include "semaphore_bsd.hpp"
  63 #include "services/attachListener.hpp"
  64 #include "services/memTracker.hpp"
  65 #include "services/runtimeService.hpp"
  66 #include "utilities/decoder.hpp"
  67 #include "utilities/defaultStream.hpp"
  68 #include "utilities/events.hpp"
  69 #include "utilities/growableArray.hpp"
  70 #include "utilities/vmError.hpp"
  71 
  72 // put OS-includes here
  73 # include <sys/types.h>
  74 # include <sys/mman.h>
  75 # include <sys/stat.h>
  76 # include <sys/select.h>
  77 # include <pthread.h>
  78 # include <signal.h>
  79 # include <errno.h>
  80 # include <dlfcn.h>
  81 # include <stdio.h>
  82 # include <unistd.h>
  83 # include <sys/resource.h>
  84 # include <pthread.h>
  85 # include <sys/stat.h>
  86 # include <sys/time.h>
  87 # include <sys/times.h>
  88 # include <sys/utsname.h>
  89 # include <sys/socket.h>
  90 # include <sys/wait.h>
  91 # include <time.h>
  92 # include <pwd.h>
  93 # include <poll.h>
  94 # include <semaphore.h>
  95 # include <fcntl.h>
  96 # include <string.h>
  97 # include <sys/param.h>
  98 # include <sys/sysctl.h>
  99 # include <sys/ipc.h>
 100 # include <sys/shm.h>
 101 #ifndef __APPLE__
 102 # include <link.h>
 103 #endif
 104 # include <stdint.h>
 105 # include <inttypes.h>
 106 # include <sys/ioctl.h>
 107 # include <sys/syscall.h>
 108 
 109 #if defined(__FreeBSD__) || defined(__NetBSD__)
 110   #include <elf.h>
 111 #endif
 112 
 113 #ifdef __APPLE__
 114   #include <mach/mach.h> // semaphore_* API
 115   #include <mach-o/dyld.h>
 116   #include <sys/proc_info.h>
 117   #include <objc/objc-auto.h>
 118 #endif
 119 
 120 #ifndef MAP_ANONYMOUS
 121   #define MAP_ANONYMOUS MAP_ANON
 122 #endif
 123 
 124 #define MAX_PATH    (2 * K)
 125 
 126 // for timer info max values which include all bits
 127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
 128 
 129 #define LARGEPAGES_BIT (1 << 6)
 130 
 131 ////////////////////////////////////////////////////////////////////////////////
 132 // global variables
 133 julong os::Bsd::_physical_memory = 0;
 134 
 135 #ifdef __APPLE__
 136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
 137 volatile uint64_t         os::Bsd::_max_abstime   = 0;
 138 #else
 139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
 140 #endif
 141 pthread_t os::Bsd::_main_thread;
 142 int os::Bsd::_page_size = -1;
 143 
 144 static jlong initial_time_count=0;
 145 
 146 static int clock_tics_per_sec = 100;
 147 
 148 // For diagnostics to print a message once. see run_periodic_checks
 149 static sigset_t check_signal_done;
 150 static bool check_signals = true;
 151 
 152 static pid_t _initial_pid = 0;
 153 
 154 // Signal number used to suspend/resume a thread
 155 
 156 // do not use any signal number less than SIGSEGV, see 4355769
 157 static int SR_signum = SIGUSR2;
 158 sigset_t SR_sigset;
 159 
 160 
 161 ////////////////////////////////////////////////////////////////////////////////
 162 // utility functions
 163 
 164 static int SR_initialize();
 165 
 166 julong os::available_memory() {
 167   return Bsd::available_memory();
 168 }
 169 
 170 // available here means free
 171 julong os::Bsd::available_memory() {
 172   uint64_t available = physical_memory() >> 2;
 173 #ifdef __APPLE__
 174   mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
 175   vm_statistics64_data_t vmstat;
 176   kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
 177                                          (host_info64_t)&vmstat, &count);
 178   assert(kerr == KERN_SUCCESS,
 179          "host_statistics64 failed - check mach_host_self() and count");
 180   if (kerr == KERN_SUCCESS) {
 181     available = vmstat.free_count * os::vm_page_size();
 182   }
 183 #endif
 184   return available;
 185 }
 186 
 187 julong os::physical_memory() {
 188   return Bsd::physical_memory();
 189 }
 190 
 191 // Return true if user is running as root.
 192 
 193 bool os::have_special_privileges() {
 194   static bool init = false;
 195   static bool privileges = false;
 196   if (!init) {
 197     privileges = (getuid() != geteuid()) || (getgid() != getegid());
 198     init = true;
 199   }
 200   return privileges;
 201 }
 202 
 203 
 204 
 205 // Cpu architecture string
 206 #if   defined(ZERO)
 207 static char cpu_arch[] = ZERO_LIBARCH;
 208 #elif defined(IA64)
 209 static char cpu_arch[] = "ia64";
 210 #elif defined(IA32)
 211 static char cpu_arch[] = "i386";
 212 #elif defined(AMD64)
 213 static char cpu_arch[] = "amd64";
 214 #elif defined(ARM)
 215 static char cpu_arch[] = "arm";
 216 #elif defined(PPC32)
 217 static char cpu_arch[] = "ppc";
 218 #elif defined(SPARC)
 219   #ifdef _LP64
 220 static char cpu_arch[] = "sparcv9";
 221   #else
 222 static char cpu_arch[] = "sparc";
 223   #endif
 224 #else
 225   #error Add appropriate cpu_arch setting
 226 #endif
 227 
 228 // Compiler variant
 229 #ifdef COMPILER2
 230   #define COMPILER_VARIANT "server"
 231 #else
 232   #define COMPILER_VARIANT "client"
 233 #endif
 234 
 235 
 236 void os::Bsd::initialize_system_info() {
 237   int mib[2];
 238   size_t len;
 239   int cpu_val;
 240   julong mem_val;
 241 
 242   // get processors count via hw.ncpus sysctl
 243   mib[0] = CTL_HW;
 244   mib[1] = HW_NCPU;
 245   len = sizeof(cpu_val);
 246   if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
 247     assert(len == sizeof(cpu_val), "unexpected data size");
 248     set_processor_count(cpu_val);
 249   } else {
 250     set_processor_count(1);   // fallback
 251   }
 252 
 253   // get physical memory via hw.memsize sysctl (hw.memsize is used
 254   // since it returns a 64 bit value)
 255   mib[0] = CTL_HW;
 256 
 257 #if defined (HW_MEMSIZE) // Apple
 258   mib[1] = HW_MEMSIZE;
 259 #elif defined(HW_PHYSMEM) // Most of BSD
 260   mib[1] = HW_PHYSMEM;
 261 #elif defined(HW_REALMEM) // Old FreeBSD
 262   mib[1] = HW_REALMEM;
 263 #else
 264   #error No ways to get physmem
 265 #endif
 266 
 267   len = sizeof(mem_val);
 268   if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
 269     assert(len == sizeof(mem_val), "unexpected data size");
 270     _physical_memory = mem_val;
 271   } else {
 272     _physical_memory = 256 * 1024 * 1024;       // fallback (XXXBSD?)
 273   }
 274 
 275 #ifdef __OpenBSD__
 276   {
 277     // limit _physical_memory memory view on OpenBSD since
 278     // datasize rlimit restricts us anyway.
 279     struct rlimit limits;
 280     getrlimit(RLIMIT_DATA, &limits);
 281     _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
 282   }
 283 #endif
 284 }
 285 
 286 #ifdef __APPLE__
 287 static const char *get_home() {
 288   const char *home_dir = ::getenv("HOME");
 289   if ((home_dir == NULL) || (*home_dir == '\0')) {
 290     struct passwd *passwd_info = getpwuid(geteuid());
 291     if (passwd_info != NULL) {
 292       home_dir = passwd_info->pw_dir;
 293     }
 294   }
 295 
 296   return home_dir;
 297 }
 298 #endif
 299 
 300 void os::init_system_properties_values() {
 301   // The next steps are taken in the product version:
 302   //
 303   // Obtain the JAVA_HOME value from the location of libjvm.so.
 304   // This library should be located at:
 305   // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
 306   //
 307   // If "/jre/lib/" appears at the right place in the path, then we
 308   // assume libjvm.so is installed in a JDK and we use this path.
 309   //
 310   // Otherwise exit with message: "Could not create the Java virtual machine."
 311   //
 312   // The following extra steps are taken in the debugging version:
 313   //
 314   // If "/jre/lib/" does NOT appear at the right place in the path
 315   // instead of exit check for $JAVA_HOME environment variable.
 316   //
 317   // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
 318   // then we append a fake suffix "hotspot/libjvm.so" to this path so
 319   // it looks like libjvm.so is installed there
 320   // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
 321   //
 322   // Otherwise exit.
 323   //
 324   // Important note: if the location of libjvm.so changes this
 325   // code needs to be changed accordingly.
 326 
 327   // See ld(1):
 328   //      The linker uses the following search paths to locate required
 329   //      shared libraries:
 330   //        1: ...
 331   //        ...
 332   //        7: The default directories, normally /lib and /usr/lib.
 333 #ifndef DEFAULT_LIBPATH
 334   #define DEFAULT_LIBPATH "/lib:/usr/lib"
 335 #endif
 336 
 337 // Base path of extensions installed on the system.
 338 #define SYS_EXT_DIR     "/usr/java/packages"
 339 #define EXTENSIONS_DIR  "/lib/ext"
 340 
 341 #ifndef __APPLE__
 342 
 343   // Buffer that fits several sprintfs.
 344   // Note that the space for the colon and the trailing null are provided
 345   // by the nulls included by the sizeof operator.
 346   const size_t bufsize =
 347     MAX2((size_t)MAXPATHLEN,  // For dll_dir & friends.
 348          (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
 349   char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
 350 
 351   // sysclasspath, java_home, dll_dir
 352   {
 353     char *pslash;
 354     os::jvm_path(buf, bufsize);
 355 
 356     // Found the full path to libjvm.so.
 357     // Now cut the path to <java_home>/jre if we can.
 358     *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
 359     pslash = strrchr(buf, '/');
 360     if (pslash != NULL) {
 361       *pslash = '\0';            // Get rid of /{client|server|hotspot}.
 362     }
 363     Arguments::set_dll_dir(buf);
 364 
 365     if (pslash != NULL) {
 366       pslash = strrchr(buf, '/');
 367       if (pslash != NULL) {
 368         *pslash = '\0';          // Get rid of /<arch>.
 369         pslash = strrchr(buf, '/');
 370         if (pslash != NULL) {
 371           *pslash = '\0';        // Get rid of /lib.
 372         }
 373       }
 374     }
 375     Arguments::set_java_home(buf);
 376     set_boot_path('/', ':');
 377   }
 378 
 379   // Where to look for native libraries.
 380   //
 381   // Note: Due to a legacy implementation, most of the library path
 382   // is set in the launcher. This was to accomodate linking restrictions
 383   // on legacy Bsd implementations (which are no longer supported).
 384   // Eventually, all the library path setting will be done here.
 385   //
 386   // However, to prevent the proliferation of improperly built native
 387   // libraries, the new path component /usr/java/packages is added here.
 388   // Eventually, all the library path setting will be done here.
 389   {
 390     // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
 391     // should always exist (until the legacy problem cited above is
 392     // addressed).
 393     const char *v = ::getenv("LD_LIBRARY_PATH");
 394     const char *v_colon = ":";
 395     if (v == NULL) { v = ""; v_colon = ""; }
 396     // That's +1 for the colon and +1 for the trailing '\0'.
 397     char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
 398                                                      strlen(v) + 1 +
 399                                                      sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
 400                                                      mtInternal);
 401     sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
 402     Arguments::set_library_path(ld_library_path);
 403     FREE_C_HEAP_ARRAY(char, ld_library_path);
 404   }
 405 
 406   // Extensions directories.
 407   sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
 408   Arguments::set_ext_dirs(buf);
 409 
 410   FREE_C_HEAP_ARRAY(char, buf);
 411 
 412 #else // __APPLE__
 413 
 414   #define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
 415   #define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
 416 
 417   const char *user_home_dir = get_home();
 418   // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
 419   size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
 420     sizeof(SYS_EXTENSIONS_DIRS);
 421 
 422   // Buffer that fits several sprintfs.
 423   // Note that the space for the colon and the trailing null are provided
 424   // by the nulls included by the sizeof operator.
 425   const size_t bufsize =
 426     MAX2((size_t)MAXPATHLEN,  // for dll_dir & friends.
 427          (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
 428   char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
 429 
 430   // sysclasspath, java_home, dll_dir
 431   {
 432     char *pslash;
 433     os::jvm_path(buf, bufsize);
 434 
 435     // Found the full path to libjvm.so.
 436     // Now cut the path to <java_home>/jre if we can.
 437     *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
 438     pslash = strrchr(buf, '/');
 439     if (pslash != NULL) {
 440       *pslash = '\0';            // Get rid of /{client|server|hotspot}.
 441     }
 442 #ifdef STATIC_BUILD
 443     strcat(buf, "/lib");
 444 #endif
 445 
 446     Arguments::set_dll_dir(buf);
 447 
 448     if (pslash != NULL) {
 449       pslash = strrchr(buf, '/');
 450       if (pslash != NULL) {
 451         *pslash = '\0';          // Get rid of /lib.
 452       }
 453     }
 454     Arguments::set_java_home(buf);
 455     set_boot_path('/', ':');
 456   }
 457 
 458   // Where to look for native libraries.
 459   //
 460   // Note: Due to a legacy implementation, most of the library path
 461   // is set in the launcher. This was to accomodate linking restrictions
 462   // on legacy Bsd implementations (which are no longer supported).
 463   // Eventually, all the library path setting will be done here.
 464   //
 465   // However, to prevent the proliferation of improperly built native
 466   // libraries, the new path component /usr/java/packages is added here.
 467   // Eventually, all the library path setting will be done here.
 468   {
 469     // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
 470     // should always exist (until the legacy problem cited above is
 471     // addressed).
 472     // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
 473     // can specify a directory inside an app wrapper
 474     const char *l = ::getenv("JAVA_LIBRARY_PATH");
 475     const char *l_colon = ":";
 476     if (l == NULL) { l = ""; l_colon = ""; }
 477 
 478     const char *v = ::getenv("DYLD_LIBRARY_PATH");
 479     const char *v_colon = ":";
 480     if (v == NULL) { v = ""; v_colon = ""; }
 481 
 482     // Apple's Java6 has "." at the beginning of java.library.path.
 483     // OpenJDK on Windows has "." at the end of java.library.path.
 484     // OpenJDK on Linux and Solaris don't have "." in java.library.path
 485     // at all. To ease the transition from Apple's Java6 to OpenJDK7,
 486     // "." is appended to the end of java.library.path. Yes, this
 487     // could cause a change in behavior, but Apple's Java6 behavior
 488     // can be achieved by putting "." at the beginning of the
 489     // JAVA_LIBRARY_PATH environment variable.
 490     char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
 491                                                      strlen(v) + 1 + strlen(l) + 1 +
 492                                                      system_ext_size + 3,
 493                                                      mtInternal);
 494     sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
 495             v, v_colon, l, l_colon, user_home_dir);
 496     Arguments::set_library_path(ld_library_path);
 497     FREE_C_HEAP_ARRAY(char, ld_library_path);
 498   }
 499 
 500   // Extensions directories.
 501   //
 502   // Note that the space for the colon and the trailing null are provided
 503   // by the nulls included by the sizeof operator (so actually one byte more
 504   // than necessary is allocated).
 505   sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
 506           user_home_dir, Arguments::get_java_home());
 507   Arguments::set_ext_dirs(buf);
 508 
 509   FREE_C_HEAP_ARRAY(char, buf);
 510 
 511 #undef SYS_EXTENSIONS_DIR
 512 #undef SYS_EXTENSIONS_DIRS
 513 
 514 #endif // __APPLE__
 515 
 516 #undef SYS_EXT_DIR
 517 #undef EXTENSIONS_DIR
 518 }
 519 
 520 ////////////////////////////////////////////////////////////////////////////////
 521 // breakpoint support
 522 
 523 void os::breakpoint() {
 524   BREAKPOINT;
 525 }
 526 
 527 extern "C" void breakpoint() {
 528   // use debugger to set breakpoint here
 529 }
 530 
 531 ////////////////////////////////////////////////////////////////////////////////
 532 // signal support
 533 
 534 debug_only(static bool signal_sets_initialized = false);
 535 static sigset_t unblocked_sigs, vm_sigs;
 536 
 537 bool os::Bsd::is_sig_ignored(int sig) {
 538   struct sigaction oact;
 539   sigaction(sig, (struct sigaction*)NULL, &oact);
 540   void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
 541                                  : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
 542   if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
 543     return true;
 544   } else {
 545     return false;
 546   }
 547 }
 548 
 549 void os::Bsd::signal_sets_init() {
 550   // Should also have an assertion stating we are still single-threaded.
 551   assert(!signal_sets_initialized, "Already initialized");
 552   // Fill in signals that are necessarily unblocked for all threads in
 553   // the VM. Currently, we unblock the following signals:
 554   // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
 555   //                         by -Xrs (=ReduceSignalUsage));
 556   // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
 557   // other threads. The "ReduceSignalUsage" boolean tells us not to alter
 558   // the dispositions or masks wrt these signals.
 559   // Programs embedding the VM that want to use the above signals for their
 560   // own purposes must, at this time, use the "-Xrs" option to prevent
 561   // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
 562   // (See bug 4345157, and other related bugs).
 563   // In reality, though, unblocking these signals is really a nop, since
 564   // these signals are not blocked by default.
 565   sigemptyset(&unblocked_sigs);
 566   sigaddset(&unblocked_sigs, SIGILL);
 567   sigaddset(&unblocked_sigs, SIGSEGV);
 568   sigaddset(&unblocked_sigs, SIGBUS);
 569   sigaddset(&unblocked_sigs, SIGFPE);
 570   sigaddset(&unblocked_sigs, SR_signum);
 571 
 572   if (!ReduceSignalUsage) {
 573     if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
 574       sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
 575 
 576     }
 577     if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
 578       sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
 579     }
 580     if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
 581       sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
 582     }
 583   }
 584   // Fill in signals that are blocked by all but the VM thread.
 585   sigemptyset(&vm_sigs);
 586   if (!ReduceSignalUsage) {
 587     sigaddset(&vm_sigs, BREAK_SIGNAL);
 588   }
 589   debug_only(signal_sets_initialized = true);
 590 
 591 }
 592 
 593 // These are signals that are unblocked while a thread is running Java.
 594 // (For some reason, they get blocked by default.)
 595 sigset_t* os::Bsd::unblocked_signals() {
 596   assert(signal_sets_initialized, "Not initialized");
 597   return &unblocked_sigs;
 598 }
 599 
 600 // These are the signals that are blocked while a (non-VM) thread is
 601 // running Java. Only the VM thread handles these signals.
 602 sigset_t* os::Bsd::vm_signals() {
 603   assert(signal_sets_initialized, "Not initialized");
 604   return &vm_sigs;
 605 }
 606 
 607 void os::Bsd::hotspot_sigmask(Thread* thread) {
 608 
 609   //Save caller's signal mask before setting VM signal mask
 610   sigset_t caller_sigmask;
 611   pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
 612 
 613   OSThread* osthread = thread->osthread();
 614   osthread->set_caller_sigmask(caller_sigmask);
 615 
 616   pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
 617 
 618   if (!ReduceSignalUsage) {
 619     if (thread->is_VM_thread()) {
 620       // Only the VM thread handles BREAK_SIGNAL ...
 621       pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
 622     } else {
 623       // ... all other threads block BREAK_SIGNAL
 624       pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
 625     }
 626   }
 627 }
 628 
 629 
 630 //////////////////////////////////////////////////////////////////////////////
 631 // create new thread
 632 
 633 #ifdef __APPLE__
 634 // library handle for calling objc_registerThreadWithCollector()
 635 // without static linking to the libobjc library
 636   #define OBJC_LIB "/usr/lib/libobjc.dylib"
 637   #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
 638 typedef void (*objc_registerThreadWithCollector_t)();
 639 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
 640 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
 641 #endif
 642 
 643 #ifdef __APPLE__
 644 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
 645   // Additional thread_id used to correlate threads in SA
 646   thread_identifier_info_data_t     m_ident_info;
 647   mach_msg_type_number_t            count = THREAD_IDENTIFIER_INFO_COUNT;
 648 
 649   thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
 650               (thread_info_t) &m_ident_info, &count);
 651 
 652   return m_ident_info.thread_id;
 653 }
 654 #endif
 655 
 656 // Thread start routine for all newly created threads
 657 static void *thread_native_entry(Thread *thread) {
 658   // Try to randomize the cache line index of hot stack frames.
 659   // This helps when threads of the same stack traces evict each other's
 660   // cache lines. The threads can be either from the same JVM instance, or
 661   // from different JVM instances. The benefit is especially true for
 662   // processors with hyperthreading technology.
 663   static int counter = 0;
 664   int pid = os::current_process_id();
 665   alloca(((pid ^ counter++) & 7) * 128);
 666 
 667   thread->initialize_thread_current();
 668 
 669   OSThread* osthread = thread->osthread();
 670   Monitor* sync = osthread->startThread_lock();
 671 
 672   osthread->set_thread_id(os::Bsd::gettid());
 673 
 674   log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
 675     os::current_thread_id(), (uintx) pthread_self());
 676 
 677 #ifdef __APPLE__
 678   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
 679   guarantee(unique_thread_id != 0, "unique thread id was not found");
 680   osthread->set_unique_thread_id(unique_thread_id);
 681 #endif
 682   // initialize signal mask for this thread
 683   os::Bsd::hotspot_sigmask(thread);
 684 
 685   // initialize floating point control register
 686   os::Bsd::init_thread_fpu_state();
 687 
 688 #ifdef __APPLE__
 689   // register thread with objc gc
 690   if (objc_registerThreadWithCollectorFunction != NULL) {
 691     objc_registerThreadWithCollectorFunction();
 692   }
 693 #endif
 694 
 695   // handshaking with parent thread
 696   {
 697     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
 698 
 699     // notify parent thread
 700     osthread->set_state(INITIALIZED);
 701     sync->notify_all();
 702 
 703     // wait until os::start_thread()
 704     while (osthread->get_state() == INITIALIZED) {
 705       sync->wait(Mutex::_no_safepoint_check_flag);
 706     }
 707   }
 708 
 709   // call one more level start routine
 710   thread->run();
 711 
 712   log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
 713     os::current_thread_id(), (uintx) pthread_self());
 714 
 715   // If a thread has not deleted itself ("delete this") as part of its
 716   // termination sequence, we have to ensure thread-local-storage is
 717   // cleared before we actually terminate. No threads should ever be
 718   // deleted asynchronously with respect to their termination.
 719   if (Thread::current_or_null_safe() != NULL) {
 720     assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
 721     thread->clear_thread_current();
 722   }
 723 
 724   return 0;
 725 }
 726 
 727 bool os::create_thread(Thread* thread, ThreadType thr_type,
 728                        size_t req_stack_size) {
 729   assert(thread->osthread() == NULL, "caller responsible");
 730 
 731   // Allocate the OSThread object
 732   OSThread* osthread = new OSThread(NULL, NULL);
 733   if (osthread == NULL) {
 734     return false;
 735   }
 736 
 737   // set the correct thread state
 738   osthread->set_thread_type(thr_type);
 739 
 740   // Initial state is ALLOCATED but not INITIALIZED
 741   osthread->set_state(ALLOCATED);
 742 
 743   thread->set_osthread(osthread);
 744 
 745   // init thread attributes
 746   pthread_attr_t attr;
 747   pthread_attr_init(&attr);
 748   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 749 
 750   // calculate stack size if it's not specified by caller
 751   size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
 752   int status = pthread_attr_setstacksize(&attr, stack_size);
 753   assert_status(status == 0, status, "pthread_attr_setstacksize");
 754 
 755   ThreadState state;
 756 
 757   {
 758     pthread_t tid;
 759     int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
 760 
 761     char buf[64];
 762     if (ret == 0) {
 763       log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
 764         (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
 765     } else {
 766       log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
 767         os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
 768     }
 769 
 770     pthread_attr_destroy(&attr);
 771 
 772     if (ret != 0) {
 773       // Need to clean up stuff we've allocated so far
 774       thread->set_osthread(NULL);
 775       delete osthread;
 776       return false;
 777     }
 778 
 779     // Store pthread info into the OSThread
 780     osthread->set_pthread_id(tid);
 781 
 782     // Wait until child thread is either initialized or aborted
 783     {
 784       Monitor* sync_with_child = osthread->startThread_lock();
 785       MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
 786       while ((state = osthread->get_state()) == ALLOCATED) {
 787         sync_with_child->wait(Mutex::_no_safepoint_check_flag);
 788       }
 789     }
 790 
 791   }
 792 
 793   // Aborted due to thread limit being reached
 794   if (state == ZOMBIE) {
 795     thread->set_osthread(NULL);
 796     delete osthread;
 797     return false;
 798   }
 799 
 800   // The thread is returned suspended (in state INITIALIZED),
 801   // and is started higher up in the call chain
 802   assert(state == INITIALIZED, "race condition");
 803   return true;
 804 }
 805 
 806 /////////////////////////////////////////////////////////////////////////////
 807 // attach existing thread
 808 
 809 // bootstrap the main thread
 810 bool os::create_main_thread(JavaThread* thread) {
 811   assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
 812   return create_attached_thread(thread);
 813 }
 814 
 815 bool os::create_attached_thread(JavaThread* thread) {
 816 #ifdef ASSERT
 817   thread->verify_not_published();
 818 #endif
 819 
 820   // Allocate the OSThread object
 821   OSThread* osthread = new OSThread(NULL, NULL);
 822 
 823   if (osthread == NULL) {
 824     return false;
 825   }
 826 
 827   osthread->set_thread_id(os::Bsd::gettid());
 828 
 829   // Store pthread info into the OSThread
 830 #ifdef __APPLE__
 831   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
 832   guarantee(unique_thread_id != 0, "just checking");
 833   osthread->set_unique_thread_id(unique_thread_id);
 834 #endif
 835   osthread->set_pthread_id(::pthread_self());
 836 
 837   // initialize floating point control register
 838   os::Bsd::init_thread_fpu_state();
 839 
 840   // Initial thread state is RUNNABLE
 841   osthread->set_state(RUNNABLE);
 842 
 843   thread->set_osthread(osthread);
 844 
 845   // initialize signal mask for this thread
 846   // and save the caller's signal mask
 847   os::Bsd::hotspot_sigmask(thread);
 848 
 849   log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
 850     os::current_thread_id(), (uintx) pthread_self());
 851 
 852   return true;
 853 }
 854 
 855 void os::pd_start_thread(Thread* thread) {
 856   OSThread * osthread = thread->osthread();
 857   assert(osthread->get_state() != INITIALIZED, "just checking");
 858   Monitor* sync_with_child = osthread->startThread_lock();
 859   MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
 860   sync_with_child->notify();
 861 }
 862 
 863 // Free Bsd resources related to the OSThread
 864 void os::free_thread(OSThread* osthread) {
 865   assert(osthread != NULL, "osthread not set");
 866 
 867   // We are told to free resources of the argument thread,
 868   // but we can only really operate on the current thread.
 869   assert(Thread::current()->osthread() == osthread,
 870          "os::free_thread but not current thread");
 871 
 872   // Restore caller's signal mask
 873   sigset_t sigmask = osthread->caller_sigmask();
 874   pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
 875 
 876   delete osthread;
 877 }
 878 
 879 ////////////////////////////////////////////////////////////////////////////////
 880 // time support
 881 
 882 // Time since start-up in seconds to a fine granularity.
 883 // Used by VMSelfDestructTimer and the MemProfiler.
 884 double os::elapsedTime() {
 885 
 886   return ((double)os::elapsed_counter()) / os::elapsed_frequency();
 887 }
 888 
 889 jlong os::elapsed_counter() {
 890   return javaTimeNanos() - initial_time_count;
 891 }
 892 
 893 jlong os::elapsed_frequency() {
 894   return NANOSECS_PER_SEC; // nanosecond resolution
 895 }
 896 
 897 bool os::supports_vtime() { return true; }
 898 bool os::enable_vtime()   { return false; }
 899 bool os::vtime_enabled()  { return false; }
 900 
 901 double os::elapsedVTime() {
 902   // better than nothing, but not much
 903   return elapsedTime();
 904 }
 905 
 906 jlong os::javaTimeMillis() {
 907   timeval time;
 908   int status = gettimeofday(&time, NULL);
 909   assert(status != -1, "bsd error");
 910   return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
 911 }
 912 
 913 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
 914   timeval time;
 915   int status = gettimeofday(&time, NULL);
 916   assert(status != -1, "bsd error");
 917   seconds = jlong(time.tv_sec);
 918   nanos = jlong(time.tv_usec) * 1000;
 919 }
 920 
 921 #ifndef __APPLE__
 922   #ifndef CLOCK_MONOTONIC
 923     #define CLOCK_MONOTONIC (1)
 924   #endif
 925 #endif
 926 
 927 #ifdef __APPLE__
 928 void os::Bsd::clock_init() {
 929   mach_timebase_info(&_timebase_info);
 930 }
 931 #else
 932 void os::Bsd::clock_init() {
 933   struct timespec res;
 934   struct timespec tp;
 935   if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
 936       ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
 937     // yes, monotonic clock is supported
 938     _clock_gettime = ::clock_gettime;
 939   }
 940 }
 941 #endif
 942 
 943 
 944 
 945 #ifdef __APPLE__
 946 
 947 jlong os::javaTimeNanos() {
 948   const uint64_t tm = mach_absolute_time();
 949   const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
 950   const uint64_t prev = Bsd::_max_abstime;
 951   if (now <= prev) {
 952     return prev;   // same or retrograde time;
 953   }
 954   const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
 955   assert(obsv >= prev, "invariant");   // Monotonicity
 956   // If the CAS succeeded then we're done and return "now".
 957   // If the CAS failed and the observed value "obsv" is >= now then
 958   // we should return "obsv".  If the CAS failed and now > obsv > prv then
 959   // some other thread raced this thread and installed a new value, in which case
 960   // we could either (a) retry the entire operation, (b) retry trying to install now
 961   // or (c) just return obsv.  We use (c).   No loop is required although in some cases
 962   // we might discard a higher "now" value in deference to a slightly lower but freshly
 963   // installed obsv value.   That's entirely benign -- it admits no new orderings compared
 964   // to (a) or (b) -- and greatly reduces coherence traffic.
 965   // We might also condition (c) on the magnitude of the delta between obsv and now.
 966   // Avoiding excessive CAS operations to hot RW locations is critical.
 967   // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
 968   return (prev == obsv) ? now : obsv;
 969 }
 970 
 971 #else // __APPLE__
 972 
 973 jlong os::javaTimeNanos() {
 974   if (os::supports_monotonic_clock()) {
 975     struct timespec tp;
 976     int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
 977     assert(status == 0, "gettime error");
 978     jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
 979     return result;
 980   } else {
 981     timeval time;
 982     int status = gettimeofday(&time, NULL);
 983     assert(status != -1, "bsd error");
 984     jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
 985     return 1000 * usecs;
 986   }
 987 }
 988 
 989 #endif // __APPLE__
 990 
 991 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
 992   if (os::supports_monotonic_clock()) {
 993     info_ptr->max_value = ALL_64_BITS;
 994 
 995     // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
 996     info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
 997     info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
 998   } else {
 999     // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1000     info_ptr->max_value = ALL_64_BITS;
1001 
1002     // gettimeofday is a real time clock so it skips
1003     info_ptr->may_skip_backward = true;
1004     info_ptr->may_skip_forward = true;
1005   }
1006 
1007   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
1008 }
1009 
1010 // Return the real, user, and system times in seconds from an
1011 // arbitrary fixed point in the past.
1012 bool os::getTimesSecs(double* process_real_time,
1013                       double* process_user_time,
1014                       double* process_system_time) {
1015   struct tms ticks;
1016   clock_t real_ticks = times(&ticks);
1017 
1018   if (real_ticks == (clock_t) (-1)) {
1019     return false;
1020   } else {
1021     double ticks_per_second = (double) clock_tics_per_sec;
1022     *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1023     *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1024     *process_real_time = ((double) real_ticks) / ticks_per_second;
1025 
1026     return true;
1027   }
1028 }
1029 
1030 
1031 char * os::local_time_string(char *buf, size_t buflen) {
1032   struct tm t;
1033   time_t long_time;
1034   time(&long_time);
1035   localtime_r(&long_time, &t);
1036   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1037                t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1038                t.tm_hour, t.tm_min, t.tm_sec);
1039   return buf;
1040 }
1041 
1042 struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
1043   return localtime_r(clock, res);
1044 }
1045 
1046 ////////////////////////////////////////////////////////////////////////////////
1047 // runtime exit support
1048 
1049 // Note: os::shutdown() might be called very early during initialization, or
1050 // called from signal handler. Before adding something to os::shutdown(), make
1051 // sure it is async-safe and can handle partially initialized VM.
1052 void os::shutdown() {
1053 
1054   // allow PerfMemory to attempt cleanup of any persistent resources
1055   perfMemory_exit();
1056 
1057   // needs to remove object in file system
1058   AttachListener::abort();
1059 
1060   // flush buffered output, finish log files
1061   ostream_abort();
1062 
1063   // Check for abort hook
1064   abort_hook_t abort_hook = Arguments::abort_hook();
1065   if (abort_hook != NULL) {
1066     abort_hook();
1067   }
1068 
1069 }
1070 
1071 // Note: os::abort() might be called very early during initialization, or
1072 // called from signal handler. Before adding something to os::abort(), make
1073 // sure it is async-safe and can handle partially initialized VM.
1074 void os::abort(bool dump_core, void* siginfo, const void* context) {
1075   os::shutdown();
1076   if (dump_core) {
1077 #ifndef PRODUCT
1078     fdStream out(defaultStream::output_fd());
1079     out.print_raw("Current thread is ");
1080     char buf[16];
1081     jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1082     out.print_raw_cr(buf);
1083     out.print_raw_cr("Dumping core ...");
1084 #endif
1085     ::abort(); // dump core
1086   }
1087 
1088   ::exit(1);
1089 }
1090 
1091 // Die immediately, no exit hook, no abort hook, no cleanup.
1092 void os::die() {
1093   // _exit() on BsdThreads only kills current thread
1094   ::abort();
1095 }
1096 
1097 // This method is a copy of JDK's sysGetLastErrorString
1098 // from src/solaris/hpi/src/system_md.c
1099 
1100 size_t os::lasterror(char *buf, size_t len) {
1101   if (errno == 0)  return 0;
1102 
1103   const char *s = os::strerror(errno);
1104   size_t n = ::strlen(s);
1105   if (n >= len) {
1106     n = len - 1;
1107   }
1108   ::strncpy(buf, s, n);
1109   buf[n] = '\0';
1110   return n;
1111 }
1112 
1113 // Information of current thread in variety of formats
1114 pid_t os::Bsd::gettid() {
1115   int retval = -1;
1116 
1117 #ifdef __APPLE__ //XNU kernel
1118   // despite the fact mach port is actually not a thread id use it
1119   // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1120   retval = ::pthread_mach_thread_np(::pthread_self());
1121   guarantee(retval != 0, "just checking");
1122   return retval;
1123 
1124 #else
1125   #ifdef __FreeBSD__
1126   retval = syscall(SYS_thr_self);
1127   #else
1128     #ifdef __OpenBSD__
1129   retval = syscall(SYS_getthrid);
1130     #else
1131       #ifdef __NetBSD__
1132   retval = (pid_t) syscall(SYS__lwp_self);
1133       #endif
1134     #endif
1135   #endif
1136 #endif
1137 
1138   if (retval == -1) {
1139     return getpid();
1140   }
1141 }
1142 
1143 intx os::current_thread_id() {
1144 #ifdef __APPLE__
1145   return (intx)::pthread_mach_thread_np(::pthread_self());
1146 #else
1147   return (intx)::pthread_self();
1148 #endif
1149 }
1150 
1151 int os::current_process_id() {
1152 
1153   // Under the old bsd thread library, bsd gives each thread
1154   // its own process id. Because of this each thread will return
1155   // a different pid if this method were to return the result
1156   // of getpid(2). Bsd provides no api that returns the pid
1157   // of the launcher thread for the vm. This implementation
1158   // returns a unique pid, the pid of the launcher thread
1159   // that starts the vm 'process'.
1160 
1161   // Under the NPTL, getpid() returns the same pid as the
1162   // launcher thread rather than a unique pid per thread.
1163   // Use gettid() if you want the old pre NPTL behaviour.
1164 
1165   // if you are looking for the result of a call to getpid() that
1166   // returns a unique pid for the calling thread, then look at the
1167   // OSThread::thread_id() method in osThread_bsd.hpp file
1168 
1169   return (int)(_initial_pid ? _initial_pid : getpid());
1170 }
1171 
1172 // DLL functions
1173 
1174 #define JNI_LIB_PREFIX "lib"
1175 #ifdef __APPLE__
1176   #define JNI_LIB_SUFFIX ".dylib"
1177 #else
1178   #define JNI_LIB_SUFFIX ".so"
1179 #endif
1180 
1181 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1182 
1183 // This must be hard coded because it's the system's temporary
1184 // directory not the java application's temp directory, ala java.io.tmpdir.
1185 #ifdef __APPLE__
1186 // macosx has a secure per-user temporary directory
1187 char temp_path_storage[PATH_MAX];
1188 const char* os::get_temp_directory() {
1189   static char *temp_path = NULL;
1190   if (temp_path == NULL) {
1191     int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1192     if (pathSize == 0 || pathSize > PATH_MAX) {
1193       strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1194     }
1195     temp_path = temp_path_storage;
1196   }
1197   return temp_path;
1198 }
1199 #else // __APPLE__
1200 const char* os::get_temp_directory() { return "/tmp"; }
1201 #endif // __APPLE__
1202 
1203 static bool file_exists(const char* filename) {
1204   struct stat statbuf;
1205   if (filename == NULL || strlen(filename) == 0) {
1206     return false;
1207   }
1208   return os::stat(filename, &statbuf) == 0;
1209 }
1210 
1211 bool os::dll_build_name(char* buffer, size_t buflen,
1212                         const char* pname, const char* fname) {
1213   bool retval = false;
1214   // Copied from libhpi
1215   const size_t pnamelen = pname ? strlen(pname) : 0;
1216 
1217   // Return error on buffer overflow.
1218   if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1219     return retval;
1220   }
1221 
1222   if (pnamelen == 0) {
1223     snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1224     retval = true;
1225   } else if (strchr(pname, *os::path_separator()) != NULL) {
1226     int n;
1227     char** pelements = split_path(pname, &n);
1228     if (pelements == NULL) {
1229       return false;
1230     }
1231     for (int i = 0; i < n; i++) {
1232       // Really shouldn't be NULL, but check can't hurt
1233       if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1234         continue; // skip the empty path values
1235       }
1236       snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1237                pelements[i], fname);
1238       if (file_exists(buffer)) {
1239         retval = true;
1240         break;
1241       }
1242     }
1243     // release the storage
1244     for (int i = 0; i < n; i++) {
1245       if (pelements[i] != NULL) {
1246         FREE_C_HEAP_ARRAY(char, pelements[i]);
1247       }
1248     }
1249     if (pelements != NULL) {
1250       FREE_C_HEAP_ARRAY(char*, pelements);
1251     }
1252   } else {
1253     snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1254     retval = true;
1255   }
1256   return retval;
1257 }
1258 
1259 // check if addr is inside libjvm.so
1260 bool os::address_is_in_vm(address addr) {
1261   static address libjvm_base_addr;
1262   Dl_info dlinfo;
1263 
1264   if (libjvm_base_addr == NULL) {
1265     if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1266       libjvm_base_addr = (address)dlinfo.dli_fbase;
1267     }
1268     assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1269   }
1270 
1271   if (dladdr((void *)addr, &dlinfo) != 0) {
1272     if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1273   }
1274 
1275   return false;
1276 }
1277 
1278 
1279 #define MACH_MAXSYMLEN 256
1280 
1281 bool os::dll_address_to_function_name(address addr, char *buf,
1282                                       int buflen, int *offset,
1283                                       bool demangle) {
1284   // buf is not optional, but offset is optional
1285   assert(buf != NULL, "sanity check");
1286 
1287   Dl_info dlinfo;
1288   char localbuf[MACH_MAXSYMLEN];
1289 
1290   if (dladdr((void*)addr, &dlinfo) != 0) {
1291     // see if we have a matching symbol
1292     if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1293       if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1294         jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1295       }
1296       if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1297       return true;
1298     }
1299     // no matching symbol so try for just file info
1300     if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1301       if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1302                           buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1303         return true;
1304       }
1305     }
1306 
1307     // Handle non-dynamic manually:
1308     if (dlinfo.dli_fbase != NULL &&
1309         Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1310                         dlinfo.dli_fbase)) {
1311       if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1312         jio_snprintf(buf, buflen, "%s", localbuf);
1313       }
1314       return true;
1315     }
1316   }
1317   buf[0] = '\0';
1318   if (offset != NULL) *offset = -1;
1319   return false;
1320 }
1321 
1322 // ported from solaris version
1323 bool os::dll_address_to_library_name(address addr, char* buf,
1324                                      int buflen, int* offset) {
1325   // buf is not optional, but offset is optional
1326   assert(buf != NULL, "sanity check");
1327 
1328   Dl_info dlinfo;
1329 
1330   if (dladdr((void*)addr, &dlinfo) != 0) {
1331     if (dlinfo.dli_fname != NULL) {
1332       jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1333     }
1334     if (dlinfo.dli_fbase != NULL && offset != NULL) {
1335       *offset = addr - (address)dlinfo.dli_fbase;
1336     }
1337     return true;
1338   }
1339 
1340   buf[0] = '\0';
1341   if (offset) *offset = -1;
1342   return false;
1343 }
1344 
1345 // Loads .dll/.so and
1346 // in case of error it checks if .dll/.so was built for the
1347 // same architecture as Hotspot is running on
1348 
1349 #ifdef __APPLE__
1350 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1351 #ifdef STATIC_BUILD
1352   return os::get_default_process_handle();
1353 #else
1354   void * result= ::dlopen(filename, RTLD_LAZY);
1355   if (result != NULL) {
1356     // Successful loading
1357     return result;
1358   }
1359 
1360   // Read system error message into ebuf
1361   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1362   ebuf[ebuflen-1]='\0';
1363 
1364   return NULL;
1365 #endif // STATIC_BUILD
1366 }
1367 #else
1368 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1369 #ifdef STATIC_BUILD
1370   return os::get_default_process_handle();
1371 #else
1372   void * result= ::dlopen(filename, RTLD_LAZY);
1373   if (result != NULL) {
1374     // Successful loading
1375     return result;
1376   }
1377 
1378   Elf32_Ehdr elf_head;
1379 
1380   // Read system error message into ebuf
1381   // It may or may not be overwritten below
1382   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1383   ebuf[ebuflen-1]='\0';
1384   int diag_msg_max_length=ebuflen-strlen(ebuf);
1385   char* diag_msg_buf=ebuf+strlen(ebuf);
1386 
1387   if (diag_msg_max_length==0) {
1388     // No more space in ebuf for additional diagnostics message
1389     return NULL;
1390   }
1391 
1392 
1393   int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1394 
1395   if (file_descriptor < 0) {
1396     // Can't open library, report dlerror() message
1397     return NULL;
1398   }
1399 
1400   bool failed_to_read_elf_head=
1401     (sizeof(elf_head)!=
1402      (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1403 
1404   ::close(file_descriptor);
1405   if (failed_to_read_elf_head) {
1406     // file i/o error - report dlerror() msg
1407     return NULL;
1408   }
1409 
1410   typedef struct {
1411     Elf32_Half  code;         // Actual value as defined in elf.h
1412     Elf32_Half  compat_class; // Compatibility of archs at VM's sense
1413     char        elf_class;    // 32 or 64 bit
1414     char        endianess;    // MSB or LSB
1415     char*       name;         // String representation
1416   } arch_t;
1417 
1418   #ifndef EM_486
1419     #define EM_486          6               /* Intel 80486 */
1420   #endif
1421 
1422   #ifndef EM_MIPS_RS3_LE
1423     #define EM_MIPS_RS3_LE  10              /* MIPS */
1424   #endif
1425 
1426   #ifndef EM_PPC64
1427     #define EM_PPC64        21              /* PowerPC64 */
1428   #endif
1429 
1430   #ifndef EM_S390
1431     #define EM_S390         22              /* IBM System/390 */
1432   #endif
1433 
1434   #ifndef EM_IA_64
1435     #define EM_IA_64        50              /* HP/Intel IA-64 */
1436   #endif
1437 
1438   #ifndef EM_X86_64
1439     #define EM_X86_64       62              /* AMD x86-64 */
1440   #endif
1441 
1442   static const arch_t arch_array[]={
1443     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1444     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1445     {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1446     {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1447     {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1448     {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1449     {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1450     {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1451     {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1452     {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
1453     {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1454     {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1455     {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1456     {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1457     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1458     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1459   };
1460 
1461   #if  (defined IA32)
1462   static  Elf32_Half running_arch_code=EM_386;
1463   #elif   (defined AMD64)
1464   static  Elf32_Half running_arch_code=EM_X86_64;
1465   #elif  (defined IA64)
1466   static  Elf32_Half running_arch_code=EM_IA_64;
1467   #elif  (defined __sparc) && (defined _LP64)
1468   static  Elf32_Half running_arch_code=EM_SPARCV9;
1469   #elif  (defined __sparc) && (!defined _LP64)
1470   static  Elf32_Half running_arch_code=EM_SPARC;
1471   #elif  (defined __powerpc64__)
1472   static  Elf32_Half running_arch_code=EM_PPC64;
1473   #elif  (defined __powerpc__)
1474   static  Elf32_Half running_arch_code=EM_PPC;
1475   #elif  (defined ARM)
1476   static  Elf32_Half running_arch_code=EM_ARM;
1477   #elif  (defined S390)
1478   static  Elf32_Half running_arch_code=EM_S390;
1479   #elif  (defined ALPHA)
1480   static  Elf32_Half running_arch_code=EM_ALPHA;
1481   #elif  (defined MIPSEL)
1482   static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1483   #elif  (defined PARISC)
1484   static  Elf32_Half running_arch_code=EM_PARISC;
1485   #elif  (defined MIPS)
1486   static  Elf32_Half running_arch_code=EM_MIPS;
1487   #elif  (defined M68K)
1488   static  Elf32_Half running_arch_code=EM_68K;
1489   #else
1490     #error Method os::dll_load requires that one of following is defined:\
1491          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1492   #endif
1493 
1494   // Identify compatability class for VM's architecture and library's architecture
1495   // Obtain string descriptions for architectures
1496 
1497   arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1498   int running_arch_index=-1;
1499 
1500   for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1501     if (running_arch_code == arch_array[i].code) {
1502       running_arch_index    = i;
1503     }
1504     if (lib_arch.code == arch_array[i].code) {
1505       lib_arch.compat_class = arch_array[i].compat_class;
1506       lib_arch.name         = arch_array[i].name;
1507     }
1508   }
1509 
1510   assert(running_arch_index != -1,
1511          "Didn't find running architecture code (running_arch_code) in arch_array");
1512   if (running_arch_index == -1) {
1513     // Even though running architecture detection failed
1514     // we may still continue with reporting dlerror() message
1515     return NULL;
1516   }
1517 
1518   if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1519     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1520     return NULL;
1521   }
1522 
1523 #ifndef S390
1524   if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1525     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1526     return NULL;
1527   }
1528 #endif // !S390
1529 
1530   if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1531     if (lib_arch.name!=NULL) {
1532       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1533                  " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1534                  lib_arch.name, arch_array[running_arch_index].name);
1535     } else {
1536       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1537                  " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1538                  lib_arch.code,
1539                  arch_array[running_arch_index].name);
1540     }
1541   }
1542 
1543   return NULL;
1544 #endif // STATIC_BUILD
1545 }
1546 #endif // !__APPLE__
1547 
1548 void* os::get_default_process_handle() {
1549 #ifdef __APPLE__
1550   // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1551   // to avoid finding unexpected symbols on second (or later)
1552   // loads of a library.
1553   return (void*)::dlopen(NULL, RTLD_FIRST);
1554 #else
1555   return (void*)::dlopen(NULL, RTLD_LAZY);
1556 #endif
1557 }
1558 
1559 // XXX: Do we need a lock around this as per Linux?
1560 void* os::dll_lookup(void* handle, const char* name) {
1561   return dlsym(handle, name);
1562 }
1563 
1564 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1565   outputStream * out = (outputStream *) param;
1566   out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1567   return 0;
1568 }
1569 
1570 void os::print_dll_info(outputStream *st) {
1571   st->print_cr("Dynamic libraries:");
1572   if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1573     st->print_cr("Error: Cannot print dynamic libraries.");
1574   }
1575 }
1576 
1577 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1578 #ifdef RTLD_DI_LINKMAP
1579   Dl_info dli;
1580   void *handle;
1581   Link_map *map;
1582   Link_map *p;
1583 
1584   if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1585       dli.dli_fname == NULL) {
1586     return 1;
1587   }
1588   handle = dlopen(dli.dli_fname, RTLD_LAZY);
1589   if (handle == NULL) {
1590     return 1;
1591   }
1592   dlinfo(handle, RTLD_DI_LINKMAP, &map);
1593   if (map == NULL) {
1594     dlclose(handle);
1595     return 1;
1596   }
1597 
1598   while (map->l_prev != NULL)
1599     map = map->l_prev;
1600 
1601   while (map != NULL) {
1602     // Value for top_address is returned as 0 since we don't have any information about module size
1603     if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1604       dlclose(handle);
1605       return 1;
1606     }
1607     map = map->l_next;
1608   }
1609 
1610   dlclose(handle);
1611 #elif defined(__APPLE__)
1612   for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1613     // Value for top_address is returned as 0 since we don't have any information about module size
1614     if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1615       return 1;
1616     }
1617   }
1618   return 0;
1619 #else
1620   return 1;
1621 #endif
1622 }
1623 
1624 void os::get_summary_os_info(char* buf, size_t buflen) {
1625   // These buffers are small because we want this to be brief
1626   // and not use a lot of stack while generating the hs_err file.
1627   char os[100];
1628   size_t size = sizeof(os);
1629   int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1630   if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1631 #ifdef __APPLE__
1632       strncpy(os, "Darwin", sizeof(os));
1633 #elif __OpenBSD__
1634       strncpy(os, "OpenBSD", sizeof(os));
1635 #else
1636       strncpy(os, "BSD", sizeof(os));
1637 #endif
1638   }
1639 
1640   char release[100];
1641   size = sizeof(release);
1642   int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1643   if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1644       // if error, leave blank
1645       strncpy(release, "", sizeof(release));
1646   }
1647   snprintf(buf, buflen, "%s %s", os, release);
1648 }
1649 
1650 void os::print_os_info_brief(outputStream* st) {
1651   os::Posix::print_uname_info(st);
1652 }
1653 
1654 void os::print_os_info(outputStream* st) {
1655   st->print("OS:");
1656 
1657   os::Posix::print_uname_info(st);
1658 
1659   os::Posix::print_rlimit_info(st);
1660 
1661   os::Posix::print_load_average(st);
1662 }
1663 
1664 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1665   // Nothing to do for now.
1666 }
1667 
1668 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1669   unsigned int mhz;
1670   size_t size = sizeof(mhz);
1671   int mib[] = { CTL_HW, HW_CPU_FREQ };
1672   if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1673     mhz = 1;  // looks like an error but can be divided by
1674   } else {
1675     mhz /= 1000000;  // reported in millions
1676   }
1677 
1678   char model[100];
1679   size = sizeof(model);
1680   int mib_model[] = { CTL_HW, HW_MODEL };
1681   if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1682     strncpy(model, cpu_arch, sizeof(model));
1683   }
1684 
1685   char machine[100];
1686   size = sizeof(machine);
1687   int mib_machine[] = { CTL_HW, HW_MACHINE };
1688   if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1689       strncpy(machine, "", sizeof(machine));
1690   }
1691 
1692   snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1693 }
1694 
1695 void os::print_memory_info(outputStream* st) {
1696 
1697   st->print("Memory:");
1698   st->print(" %dk page", os::vm_page_size()>>10);
1699 
1700   st->print(", physical " UINT64_FORMAT "k",
1701             os::physical_memory() >> 10);
1702   st->print("(" UINT64_FORMAT "k free)",
1703             os::available_memory() >> 10);
1704   st->cr();
1705 }
1706 
1707 static void print_signal_handler(outputStream* st, int sig,
1708                                  char* buf, size_t buflen);
1709 
1710 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1711   st->print_cr("Signal Handlers:");
1712   print_signal_handler(st, SIGSEGV, buf, buflen);
1713   print_signal_handler(st, SIGBUS , buf, buflen);
1714   print_signal_handler(st, SIGFPE , buf, buflen);
1715   print_signal_handler(st, SIGPIPE, buf, buflen);
1716   print_signal_handler(st, SIGXFSZ, buf, buflen);
1717   print_signal_handler(st, SIGILL , buf, buflen);
1718   print_signal_handler(st, SR_signum, buf, buflen);
1719   print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1720   print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1721   print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1722   print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1723 }
1724 
1725 static char saved_jvm_path[MAXPATHLEN] = {0};
1726 
1727 // Find the full path to the current module, libjvm
1728 void os::jvm_path(char *buf, jint buflen) {
1729   // Error checking.
1730   if (buflen < MAXPATHLEN) {
1731     assert(false, "must use a large-enough buffer");
1732     buf[0] = '\0';
1733     return;
1734   }
1735   // Lazy resolve the path to current module.
1736   if (saved_jvm_path[0] != 0) {
1737     strcpy(buf, saved_jvm_path);
1738     return;
1739   }
1740 
1741   char dli_fname[MAXPATHLEN];
1742   bool ret = dll_address_to_library_name(
1743                                          CAST_FROM_FN_PTR(address, os::jvm_path),
1744                                          dli_fname, sizeof(dli_fname), NULL);
1745   assert(ret, "cannot locate libjvm");
1746   char *rp = NULL;
1747   if (ret && dli_fname[0] != '\0') {
1748     rp = os::Posix::realpath(dli_fname, buf, buflen);
1749   }
1750   if (rp == NULL) {
1751     return;
1752   }
1753 
1754   if (Arguments::sun_java_launcher_is_altjvm()) {
1755     // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1756     // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1757     // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1758     // appears at the right place in the string, then assume we are
1759     // installed in a JDK and we're done. Otherwise, check for a
1760     // JAVA_HOME environment variable and construct a path to the JVM
1761     // being overridden.
1762 
1763     const char *p = buf + strlen(buf) - 1;
1764     for (int count = 0; p > buf && count < 5; ++count) {
1765       for (--p; p > buf && *p != '/'; --p)
1766         /* empty */ ;
1767     }
1768 
1769     if (strncmp(p, "/jre/lib/", 9) != 0) {
1770       // Look for JAVA_HOME in the environment.
1771       char* java_home_var = ::getenv("JAVA_HOME");
1772       if (java_home_var != NULL && java_home_var[0] != 0) {
1773         char* jrelib_p;
1774         int len;
1775 
1776         // Check the current module name "libjvm"
1777         p = strrchr(buf, '/');
1778         assert(strstr(p, "/libjvm") == p, "invalid library name");
1779 
1780         rp = os::Posix::realpath(java_home_var, buf, buflen);
1781         if (rp == NULL) {
1782           return;
1783         }
1784 
1785         // determine if this is a legacy image or modules image
1786         // modules image doesn't have "jre" subdirectory
1787         len = strlen(buf);
1788         assert(len < buflen, "Ran out of buffer space");
1789         jrelib_p = buf + len;
1790 
1791         // Add the appropriate library subdir
1792         snprintf(jrelib_p, buflen-len, "/jre/lib");
1793         if (0 != access(buf, F_OK)) {
1794           snprintf(jrelib_p, buflen-len, "/lib");
1795         }
1796 
1797         // Add the appropriate client or server subdir
1798         len = strlen(buf);
1799         jrelib_p = buf + len;
1800         snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1801         if (0 != access(buf, F_OK)) {
1802           snprintf(jrelib_p, buflen-len, "%s", "");
1803         }
1804 
1805         // If the path exists within JAVA_HOME, add the JVM library name
1806         // to complete the path to JVM being overridden.  Otherwise fallback
1807         // to the path to the current library.
1808         if (0 == access(buf, F_OK)) {
1809           // Use current module name "libjvm"
1810           len = strlen(buf);
1811           snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1812         } else {
1813           // Fall back to path of current library
1814           rp = os::Posix::realpath(dli_fname, buf, buflen);
1815           if (rp == NULL) {
1816             return;
1817           }
1818         }
1819       }
1820     }
1821   }
1822 
1823   strncpy(saved_jvm_path, buf, MAXPATHLEN);
1824   saved_jvm_path[MAXPATHLEN - 1] = '\0';
1825 }
1826 
1827 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1828   // no prefix required, not even "_"
1829 }
1830 
1831 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1832   // no suffix required
1833 }
1834 
1835 ////////////////////////////////////////////////////////////////////////////////
1836 // sun.misc.Signal support
1837 
1838 static volatile jint sigint_count = 0;
1839 
1840 static void UserHandler(int sig, void *siginfo, void *context) {
1841   // 4511530 - sem_post is serialized and handled by the manager thread. When
1842   // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1843   // don't want to flood the manager thread with sem_post requests.
1844   if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1845     return;
1846   }
1847 
1848   // Ctrl-C is pressed during error reporting, likely because the error
1849   // handler fails to abort. Let VM die immediately.
1850   if (sig == SIGINT && VMError::is_error_reported()) {
1851     os::die();
1852   }
1853 
1854   os::signal_notify(sig);
1855 }
1856 
1857 void* os::user_handler() {
1858   return CAST_FROM_FN_PTR(void*, UserHandler);
1859 }
1860 
1861 extern "C" {
1862   typedef void (*sa_handler_t)(int);
1863   typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1864 }
1865 
1866 void* os::signal(int signal_number, void* handler) {
1867   struct sigaction sigAct, oldSigAct;
1868 
1869   sigfillset(&(sigAct.sa_mask));
1870   sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
1871   sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1872 
1873   if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1874     // -1 means registration failed
1875     return (void *)-1;
1876   }
1877 
1878   return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1879 }
1880 
1881 void os::signal_raise(int signal_number) {
1882   ::raise(signal_number);
1883 }
1884 
1885 // The following code is moved from os.cpp for making this
1886 // code platform specific, which it is by its very nature.
1887 
1888 // Will be modified when max signal is changed to be dynamic
1889 int os::sigexitnum_pd() {
1890   return NSIG;
1891 }
1892 
1893 // a counter for each possible signal value
1894 static volatile jint pending_signals[NSIG+1] = { 0 };
1895 
1896 // Bsd(POSIX) specific hand shaking semaphore.
1897 #ifdef __APPLE__
1898 typedef semaphore_t os_semaphore_t;
1899 
1900   #define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1901   #define SEM_WAIT(sem)           semaphore_wait(sem)
1902   #define SEM_POST(sem)           semaphore_signal(sem)
1903   #define SEM_DESTROY(sem)        semaphore_destroy(mach_task_self(), sem)
1904 #else
1905 typedef sem_t os_semaphore_t;
1906 
1907   #define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
1908   #define SEM_WAIT(sem)           sem_wait(&sem)
1909   #define SEM_POST(sem)           sem_post(&sem)
1910   #define SEM_DESTROY(sem)        sem_destroy(&sem)
1911 #endif
1912 
1913 #ifdef __APPLE__
1914 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
1915 
1916 static const char* sem_init_strerror(kern_return_t value) {
1917   switch (value) {
1918     case KERN_INVALID_ARGUMENT:  return "Invalid argument";
1919     case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
1920     default:                     return "Unknown";
1921   }
1922 }
1923 
1924 OSXSemaphore::OSXSemaphore(uint value) {
1925   kern_return_t ret = SEM_INIT(_semaphore, value);
1926 
1927   guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
1928 }
1929 
1930 OSXSemaphore::~OSXSemaphore() {
1931   SEM_DESTROY(_semaphore);
1932 }
1933 
1934 void OSXSemaphore::signal(uint count) {
1935   for (uint i = 0; i < count; i++) {
1936     kern_return_t ret = SEM_POST(_semaphore);
1937 
1938     assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
1939   }
1940 }
1941 
1942 void OSXSemaphore::wait() {
1943   kern_return_t ret;
1944   while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
1945     // Semaphore was interrupted. Retry.
1946   }
1947   assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
1948 }
1949 
1950 jlong OSXSemaphore::currenttime() {
1951   struct timeval tv;
1952   gettimeofday(&tv, NULL);
1953   return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1954 }
1955 
1956 bool OSXSemaphore::trywait() {
1957   return timedwait(0, 0);
1958 }
1959 
1960 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
1961   kern_return_t kr = KERN_ABORTED;
1962   mach_timespec_t waitspec;
1963   waitspec.tv_sec = sec;
1964   waitspec.tv_nsec = nsec;
1965 
1966   jlong starttime = currenttime();
1967 
1968   kr = semaphore_timedwait(_semaphore, waitspec);
1969   while (kr == KERN_ABORTED) {
1970     jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1971 
1972     jlong current = currenttime();
1973     jlong passedtime = current - starttime;
1974 
1975     if (passedtime >= totalwait) {
1976       waitspec.tv_sec = 0;
1977       waitspec.tv_nsec = 0;
1978     } else {
1979       jlong waittime = totalwait - (current - starttime);
1980       waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1981       waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1982     }
1983 
1984     kr = semaphore_timedwait(_semaphore, waitspec);
1985   }
1986 
1987   return kr == KERN_SUCCESS;
1988 }
1989 
1990 #else
1991 // Use POSIX implementation of semaphores.
1992 
1993 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
1994   struct timespec ts;
1995   unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1996 
1997   return ts;
1998 }
1999 
2000 #endif // __APPLE__
2001 
2002 static os_semaphore_t sig_sem;
2003 
2004 #ifdef __APPLE__
2005 static OSXSemaphore sr_semaphore;
2006 #else
2007 static PosixSemaphore sr_semaphore;
2008 #endif
2009 
2010 void os::signal_init_pd() {
2011   // Initialize signal structures
2012   ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2013 
2014   // Initialize signal semaphore
2015   ::SEM_INIT(sig_sem, 0);
2016 }
2017 
2018 void os::signal_notify(int sig) {
2019   Atomic::inc(&pending_signals[sig]);
2020   ::SEM_POST(sig_sem);
2021 }
2022 
2023 static int check_pending_signals(bool wait) {
2024   Atomic::store(0, &sigint_count);
2025   for (;;) {
2026     for (int i = 0; i < NSIG + 1; i++) {
2027       jint n = pending_signals[i];
2028       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2029         return i;
2030       }
2031     }
2032     if (!wait) {
2033       return -1;
2034     }
2035     JavaThread *thread = JavaThread::current();
2036     ThreadBlockInVM tbivm(thread);
2037 
2038     bool threadIsSuspended;
2039     do {
2040       thread->set_suspend_equivalent();
2041       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2042       ::SEM_WAIT(sig_sem);
2043 
2044       // were we externally suspended while we were waiting?
2045       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2046       if (threadIsSuspended) {
2047         // The semaphore has been incremented, but while we were waiting
2048         // another thread suspended us. We don't want to continue running
2049         // while suspended because that would surprise the thread that
2050         // suspended us.
2051         ::SEM_POST(sig_sem);
2052 
2053         thread->java_suspend_self();
2054       }
2055     } while (threadIsSuspended);
2056   }
2057 }
2058 
2059 int os::signal_lookup() {
2060   return check_pending_signals(false);
2061 }
2062 
2063 int os::signal_wait() {
2064   return check_pending_signals(true);
2065 }
2066 
2067 ////////////////////////////////////////////////////////////////////////////////
2068 // Virtual Memory
2069 
2070 int os::vm_page_size() {
2071   // Seems redundant as all get out
2072   assert(os::Bsd::page_size() != -1, "must call os::init");
2073   return os::Bsd::page_size();
2074 }
2075 
2076 // Solaris allocates memory by pages.
2077 int os::vm_allocation_granularity() {
2078   assert(os::Bsd::page_size() != -1, "must call os::init");
2079   return os::Bsd::page_size();
2080 }
2081 
2082 // Rationale behind this function:
2083 //  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2084 //  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2085 //  samples for JITted code. Here we create private executable mapping over the code cache
2086 //  and then we can use standard (well, almost, as mapping can change) way to provide
2087 //  info for the reporting script by storing timestamp and location of symbol
2088 void bsd_wrap_code(char* base, size_t size) {
2089   static volatile jint cnt = 0;
2090 
2091   if (!UseOprofile) {
2092     return;
2093   }
2094 
2095   char buf[PATH_MAX + 1];
2096   int num = Atomic::add(1, &cnt);
2097 
2098   snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2099            os::get_temp_directory(), os::current_process_id(), num);
2100   unlink(buf);
2101 
2102   int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2103 
2104   if (fd != -1) {
2105     off_t rv = ::lseek(fd, size-2, SEEK_SET);
2106     if (rv != (off_t)-1) {
2107       if (::write(fd, "", 1) == 1) {
2108         mmap(base, size,
2109              PROT_READ|PROT_WRITE|PROT_EXEC,
2110              MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2111       }
2112     }
2113     ::close(fd);
2114     unlink(buf);
2115   }
2116 }
2117 
2118 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2119                                     int err) {
2120   warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2121           ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2122           os::errno_name(err), err);
2123 }
2124 
2125 // NOTE: Bsd kernel does not really reserve the pages for us.
2126 //       All it does is to check if there are enough free pages
2127 //       left at the time of mmap(). This could be a potential
2128 //       problem.
2129 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2130   int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2131 #ifdef __OpenBSD__
2132   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2133   if (::mprotect(addr, size, prot) == 0) {
2134     return true;
2135   }
2136 #else
2137   uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2138                                      MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2139   if (res != (uintptr_t) MAP_FAILED) {
2140     return true;
2141   }
2142 #endif
2143 
2144   // Warn about any commit errors we see in non-product builds just
2145   // in case mmap() doesn't work as described on the man page.
2146   NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2147 
2148   return false;
2149 }
2150 
2151 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2152                           bool exec) {
2153   // alignment_hint is ignored on this OS
2154   return pd_commit_memory(addr, size, exec);
2155 }
2156 
2157 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2158                                   const char* mesg) {
2159   assert(mesg != NULL, "mesg must be specified");
2160   if (!pd_commit_memory(addr, size, exec)) {
2161     // add extra info in product mode for vm_exit_out_of_memory():
2162     PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2163     vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
2164   }
2165 }
2166 
2167 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2168                                   size_t alignment_hint, bool exec,
2169                                   const char* mesg) {
2170   // alignment_hint is ignored on this OS
2171   pd_commit_memory_or_exit(addr, size, exec, mesg);
2172 }
2173 
2174 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2175 }
2176 
2177 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2178   ::madvise(addr, bytes, MADV_DONTNEED);
2179 }
2180 
2181 void os::numa_make_global(char *addr, size_t bytes) {
2182 }
2183 
2184 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2185 }
2186 
2187 bool os::numa_topology_changed()   { return false; }
2188 
2189 size_t os::numa_get_groups_num() {
2190   return 1;
2191 }
2192 
2193 int os::numa_get_group_id() {
2194   return 0;
2195 }
2196 
2197 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2198   if (size > 0) {
2199     ids[0] = 0;
2200     return 1;
2201   }
2202   return 0;
2203 }
2204 
2205 bool os::get_page_info(char *start, page_info* info) {
2206   return false;
2207 }
2208 
2209 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2210   return end;
2211 }
2212 
2213 
2214 bool os::pd_uncommit_memory(char* addr, size_t size) {
2215 #ifdef __OpenBSD__
2216   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2217   return ::mprotect(addr, size, PROT_NONE) == 0;
2218 #else
2219   uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2220                                      MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2221   return res  != (uintptr_t) MAP_FAILED;
2222 #endif
2223 }
2224 
2225 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2226   return os::commit_memory(addr, size, !ExecMem);
2227 }
2228 
2229 // If this is a growable mapping, remove the guard pages entirely by
2230 // munmap()ping them.  If not, just call uncommit_memory().
2231 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2232   return os::uncommit_memory(addr, size);
2233 }
2234 
2235 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2236 // at 'requested_addr'. If there are existing memory mappings at the same
2237 // location, however, they will be overwritten. If 'fixed' is false,
2238 // 'requested_addr' is only treated as a hint, the return value may or
2239 // may not start from the requested address. Unlike Bsd mmap(), this
2240 // function returns NULL to indicate failure.
2241 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2242   char * addr;
2243   int flags;
2244 
2245   flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2246   if (fixed) {
2247     assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2248     flags |= MAP_FIXED;
2249   }
2250 
2251   // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2252   // touch an uncommitted page. Otherwise, the read/write might
2253   // succeed if we have enough swap space to back the physical page.
2254   addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2255                        flags, -1, 0);
2256 
2257   return addr == MAP_FAILED ? NULL : addr;
2258 }
2259 
2260 static int anon_munmap(char * addr, size_t size) {
2261   return ::munmap(addr, size) == 0;
2262 }
2263 
2264 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2265                             size_t alignment_hint) {
2266   return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2267 }
2268 
2269 bool os::pd_release_memory(char* addr, size_t size) {
2270   return anon_munmap(addr, size);
2271 }
2272 
2273 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2274   // Bsd wants the mprotect address argument to be page aligned.
2275   char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2276 
2277   // According to SUSv3, mprotect() should only be used with mappings
2278   // established by mmap(), and mmap() always maps whole pages. Unaligned
2279   // 'addr' likely indicates problem in the VM (e.g. trying to change
2280   // protection of malloc'ed or statically allocated memory). Check the
2281   // caller if you hit this assert.
2282   assert(addr == bottom, "sanity check");
2283 
2284   size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2285   return ::mprotect(bottom, size, prot) == 0;
2286 }
2287 
2288 // Set protections specified
2289 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2290                         bool is_committed) {
2291   unsigned int p = 0;
2292   switch (prot) {
2293   case MEM_PROT_NONE: p = PROT_NONE; break;
2294   case MEM_PROT_READ: p = PROT_READ; break;
2295   case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
2296   case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2297   default:
2298     ShouldNotReachHere();
2299   }
2300   // is_committed is unused.
2301   return bsd_mprotect(addr, bytes, p);
2302 }
2303 
2304 bool os::guard_memory(char* addr, size_t size) {
2305   return bsd_mprotect(addr, size, PROT_NONE);
2306 }
2307 
2308 bool os::unguard_memory(char* addr, size_t size) {
2309   return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2310 }
2311 
2312 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2313   return false;
2314 }
2315 
2316 // Large page support
2317 
2318 static size_t _large_page_size = 0;
2319 
2320 void os::large_page_init() {
2321 }
2322 
2323 
2324 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2325   fatal("This code is not used or maintained.");
2326 
2327   // "exec" is passed in but not used.  Creating the shared image for
2328   // the code cache doesn't have an SHM_X executable permission to check.
2329   assert(UseLargePages && UseSHM, "only for SHM large pages");
2330 
2331   key_t key = IPC_PRIVATE;
2332   char *addr;
2333 
2334   bool warn_on_failure = UseLargePages &&
2335                          (!FLAG_IS_DEFAULT(UseLargePages) ||
2336                           !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2337 
2338   // Create a large shared memory region to attach to based on size.
2339   // Currently, size is the total size of the heap
2340   int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2341   if (shmid == -1) {
2342     // Possible reasons for shmget failure:
2343     // 1. shmmax is too small for Java heap.
2344     //    > check shmmax value: cat /proc/sys/kernel/shmmax
2345     //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2346     // 2. not enough large page memory.
2347     //    > check available large pages: cat /proc/meminfo
2348     //    > increase amount of large pages:
2349     //          echo new_value > /proc/sys/vm/nr_hugepages
2350     //      Note 1: different Bsd may use different name for this property,
2351     //            e.g. on Redhat AS-3 it is "hugetlb_pool".
2352     //      Note 2: it's possible there's enough physical memory available but
2353     //            they are so fragmented after a long run that they can't
2354     //            coalesce into large pages. Try to reserve large pages when
2355     //            the system is still "fresh".
2356     if (warn_on_failure) {
2357       warning("Failed to reserve shared memory (errno = %d).", errno);
2358     }
2359     return NULL;
2360   }
2361 
2362   // attach to the region
2363   addr = (char*)shmat(shmid, req_addr, 0);
2364   int err = errno;
2365 
2366   // Remove shmid. If shmat() is successful, the actual shared memory segment
2367   // will be deleted when it's detached by shmdt() or when the process
2368   // terminates. If shmat() is not successful this will remove the shared
2369   // segment immediately.
2370   shmctl(shmid, IPC_RMID, NULL);
2371 
2372   if ((intptr_t)addr == -1) {
2373     if (warn_on_failure) {
2374       warning("Failed to attach shared memory (errno = %d).", err);
2375     }
2376     return NULL;
2377   }
2378 
2379   // The memory is committed
2380   MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2381 
2382   return addr;
2383 }
2384 
2385 bool os::release_memory_special(char* base, size_t bytes) {
2386   if (MemTracker::tracking_level() > NMT_minimal) {
2387     Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2388     // detaching the SHM segment will also delete it, see reserve_memory_special()
2389     int rslt = shmdt(base);
2390     if (rslt == 0) {
2391       tkr.record((address)base, bytes);
2392       return true;
2393     } else {
2394       return false;
2395     }
2396   } else {
2397     return shmdt(base) == 0;
2398   }
2399 }
2400 
2401 size_t os::large_page_size() {
2402   return _large_page_size;
2403 }
2404 
2405 // HugeTLBFS allows application to commit large page memory on demand;
2406 // with SysV SHM the entire memory region must be allocated as shared
2407 // memory.
2408 bool os::can_commit_large_page_memory() {
2409   return UseHugeTLBFS;
2410 }
2411 
2412 bool os::can_execute_large_page_memory() {
2413   return UseHugeTLBFS;
2414 }
2415 
2416 // Reserve memory at an arbitrary address, only if that area is
2417 // available (and not reserved for something else).
2418 
2419 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2420   const int max_tries = 10;
2421   char* base[max_tries];
2422   size_t size[max_tries];
2423   const size_t gap = 0x000000;
2424 
2425   // Assert only that the size is a multiple of the page size, since
2426   // that's all that mmap requires, and since that's all we really know
2427   // about at this low abstraction level.  If we need higher alignment,
2428   // we can either pass an alignment to this method or verify alignment
2429   // in one of the methods further up the call chain.  See bug 5044738.
2430   assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2431 
2432   // Repeatedly allocate blocks until the block is allocated at the
2433   // right spot.
2434 
2435   // Bsd mmap allows caller to pass an address as hint; give it a try first,
2436   // if kernel honors the hint then we can return immediately.
2437   char * addr = anon_mmap(requested_addr, bytes, false);
2438   if (addr == requested_addr) {
2439     return requested_addr;
2440   }
2441 
2442   if (addr != NULL) {
2443     // mmap() is successful but it fails to reserve at the requested address
2444     anon_munmap(addr, bytes);
2445   }
2446 
2447   int i;
2448   for (i = 0; i < max_tries; ++i) {
2449     base[i] = reserve_memory(bytes);
2450 
2451     if (base[i] != NULL) {
2452       // Is this the block we wanted?
2453       if (base[i] == requested_addr) {
2454         size[i] = bytes;
2455         break;
2456       }
2457 
2458       // Does this overlap the block we wanted? Give back the overlapped
2459       // parts and try again.
2460 
2461       size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2462       if (top_overlap >= 0 && top_overlap < bytes) {
2463         unmap_memory(base[i], top_overlap);
2464         base[i] += top_overlap;
2465         size[i] = bytes - top_overlap;
2466       } else {
2467         size_t bottom_overlap = base[i] + bytes - requested_addr;
2468         if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2469           unmap_memory(requested_addr, bottom_overlap);
2470           size[i] = bytes - bottom_overlap;
2471         } else {
2472           size[i] = bytes;
2473         }
2474       }
2475     }
2476   }
2477 
2478   // Give back the unused reserved pieces.
2479 
2480   for (int j = 0; j < i; ++j) {
2481     if (base[j] != NULL) {
2482       unmap_memory(base[j], size[j]);
2483     }
2484   }
2485 
2486   if (i < max_tries) {
2487     return requested_addr;
2488   } else {
2489     return NULL;
2490   }
2491 }
2492 
2493 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2494   RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2495 }
2496 
2497 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2498   RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2499 }
2500 
2501 void os::naked_short_sleep(jlong ms) {
2502   struct timespec req;
2503 
2504   assert(ms < 1000, "Un-interruptable sleep, short time use only");
2505   req.tv_sec = 0;
2506   if (ms > 0) {
2507     req.tv_nsec = (ms % 1000) * 1000000;
2508   } else {
2509     req.tv_nsec = 1;
2510   }
2511 
2512   nanosleep(&req, NULL);
2513 
2514   return;
2515 }
2516 
2517 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2518 void os::infinite_sleep() {
2519   while (true) {    // sleep forever ...
2520     ::sleep(100);   // ... 100 seconds at a time
2521   }
2522 }
2523 
2524 // Used to convert frequent JVM_Yield() to nops
2525 bool os::dont_yield() {
2526   return DontYieldALot;
2527 }
2528 
2529 void os::naked_yield() {
2530   sched_yield();
2531 }
2532 
2533 ////////////////////////////////////////////////////////////////////////////////
2534 // thread priority support
2535 
2536 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2537 // only supports dynamic priority, static priority must be zero. For real-time
2538 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2539 // However, for large multi-threaded applications, SCHED_RR is not only slower
2540 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2541 // of 5 runs - Sep 2005).
2542 //
2543 // The following code actually changes the niceness of kernel-thread/LWP. It
2544 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2545 // not the entire user process, and user level threads are 1:1 mapped to kernel
2546 // threads. It has always been the case, but could change in the future. For
2547 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2548 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2549 
2550 #if !defined(__APPLE__)
2551 int os::java_to_os_priority[CriticalPriority + 1] = {
2552   19,              // 0 Entry should never be used
2553 
2554    0,              // 1 MinPriority
2555    3,              // 2
2556    6,              // 3
2557 
2558   10,              // 4
2559   15,              // 5 NormPriority
2560   18,              // 6
2561 
2562   21,              // 7
2563   25,              // 8
2564   28,              // 9 NearMaxPriority
2565 
2566   31,              // 10 MaxPriority
2567 
2568   31               // 11 CriticalPriority
2569 };
2570 #else
2571 // Using Mach high-level priority assignments
2572 int os::java_to_os_priority[CriticalPriority + 1] = {
2573    0,              // 0 Entry should never be used (MINPRI_USER)
2574 
2575   27,              // 1 MinPriority
2576   28,              // 2
2577   29,              // 3
2578 
2579   30,              // 4
2580   31,              // 5 NormPriority (BASEPRI_DEFAULT)
2581   32,              // 6
2582 
2583   33,              // 7
2584   34,              // 8
2585   35,              // 9 NearMaxPriority
2586 
2587   36,              // 10 MaxPriority
2588 
2589   36               // 11 CriticalPriority
2590 };
2591 #endif
2592 
2593 static int prio_init() {
2594   if (ThreadPriorityPolicy == 1) {
2595     // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2596     // if effective uid is not root. Perhaps, a more elegant way of doing
2597     // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2598     if (geteuid() != 0) {
2599       if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2600         warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2601       }
2602       ThreadPriorityPolicy = 0;
2603     }
2604   }
2605   if (UseCriticalJavaThreadPriority) {
2606     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2607   }
2608   return 0;
2609 }
2610 
2611 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2612   if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2613 
2614 #ifdef __OpenBSD__
2615   // OpenBSD pthread_setprio starves low priority threads
2616   return OS_OK;
2617 #elif defined(__FreeBSD__)
2618   int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2619 #elif defined(__APPLE__) || defined(__NetBSD__)
2620   struct sched_param sp;
2621   int policy;
2622   pthread_t self = pthread_self();
2623 
2624   if (pthread_getschedparam(self, &policy, &sp) != 0) {
2625     return OS_ERR;
2626   }
2627 
2628   sp.sched_priority = newpri;
2629   if (pthread_setschedparam(self, policy, &sp) != 0) {
2630     return OS_ERR;
2631   }
2632 
2633   return OS_OK;
2634 #else
2635   int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2636   return (ret == 0) ? OS_OK : OS_ERR;
2637 #endif
2638 }
2639 
2640 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2641   if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2642     *priority_ptr = java_to_os_priority[NormPriority];
2643     return OS_OK;
2644   }
2645 
2646   errno = 0;
2647 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2648   *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2649 #elif defined(__APPLE__) || defined(__NetBSD__)
2650   int policy;
2651   struct sched_param sp;
2652 
2653   pthread_getschedparam(pthread_self(), &policy, &sp);
2654   *priority_ptr = sp.sched_priority;
2655 #else
2656   *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2657 #endif
2658   return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2659 }
2660 
2661 // Hint to the underlying OS that a task switch would not be good.
2662 // Void return because it's a hint and can fail.
2663 void os::hint_no_preempt() {}
2664 
2665 ////////////////////////////////////////////////////////////////////////////////
2666 // suspend/resume support
2667 
2668 //  the low-level signal-based suspend/resume support is a remnant from the
2669 //  old VM-suspension that used to be for java-suspension, safepoints etc,
2670 //  within hotspot. Now there is a single use-case for this:
2671 //    - calling get_thread_pc() on the VMThread by the flat-profiler task
2672 //      that runs in the watcher thread.
2673 //  The remaining code is greatly simplified from the more general suspension
2674 //  code that used to be used.
2675 //
2676 //  The protocol is quite simple:
2677 //  - suspend:
2678 //      - sends a signal to the target thread
2679 //      - polls the suspend state of the osthread using a yield loop
2680 //      - target thread signal handler (SR_handler) sets suspend state
2681 //        and blocks in sigsuspend until continued
2682 //  - resume:
2683 //      - sets target osthread state to continue
2684 //      - sends signal to end the sigsuspend loop in the SR_handler
2685 //
2686 //  Note that the SR_lock plays no role in this suspend/resume protocol,
2687 //  but is checked for NULL in SR_handler as a thread termination indicator.
2688 
2689 static void resume_clear_context(OSThread *osthread) {
2690   osthread->set_ucontext(NULL);
2691   osthread->set_siginfo(NULL);
2692 }
2693 
2694 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2695   osthread->set_ucontext(context);
2696   osthread->set_siginfo(siginfo);
2697 }
2698 
2699 // Handler function invoked when a thread's execution is suspended or
2700 // resumed. We have to be careful that only async-safe functions are
2701 // called here (Note: most pthread functions are not async safe and
2702 // should be avoided.)
2703 //
2704 // Note: sigwait() is a more natural fit than sigsuspend() from an
2705 // interface point of view, but sigwait() prevents the signal hander
2706 // from being run. libpthread would get very confused by not having
2707 // its signal handlers run and prevents sigwait()'s use with the
2708 // mutex granting granting signal.
2709 //
2710 // Currently only ever called on the VMThread or JavaThread
2711 //
2712 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2713   // Save and restore errno to avoid confusing native code with EINTR
2714   // after sigsuspend.
2715   int old_errno = errno;
2716 
2717   Thread* thread = Thread::current_or_null_safe();
2718   assert(thread != NULL, "Missing current thread in SR_handler");
2719 
2720   // On some systems we have seen signal delivery get "stuck" until the signal
2721   // mask is changed as part of thread termination. Check that the current thread
2722   // has not already terminated (via SR_lock()) - else the following assertion
2723   // will fail because the thread is no longer a JavaThread as the ~JavaThread
2724   // destructor has completed.
2725 
2726   if (thread->SR_lock() == NULL) {
2727     return;
2728   }
2729 
2730   assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2731 
2732   OSThread* osthread = thread->osthread();
2733 
2734   os::SuspendResume::State current = osthread->sr.state();
2735   if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2736     suspend_save_context(osthread, siginfo, context);
2737 
2738     // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2739     os::SuspendResume::State state = osthread->sr.suspended();
2740     if (state == os::SuspendResume::SR_SUSPENDED) {
2741       sigset_t suspend_set;  // signals for sigsuspend()
2742 
2743       // get current set of blocked signals and unblock resume signal
2744       pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2745       sigdelset(&suspend_set, SR_signum);
2746 
2747       sr_semaphore.signal();
2748       // wait here until we are resumed
2749       while (1) {
2750         sigsuspend(&suspend_set);
2751 
2752         os::SuspendResume::State result = osthread->sr.running();
2753         if (result == os::SuspendResume::SR_RUNNING) {
2754           sr_semaphore.signal();
2755           break;
2756         } else if (result != os::SuspendResume::SR_SUSPENDED) {
2757           ShouldNotReachHere();
2758         }
2759       }
2760 
2761     } else if (state == os::SuspendResume::SR_RUNNING) {
2762       // request was cancelled, continue
2763     } else {
2764       ShouldNotReachHere();
2765     }
2766 
2767     resume_clear_context(osthread);
2768   } else if (current == os::SuspendResume::SR_RUNNING) {
2769     // request was cancelled, continue
2770   } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2771     // ignore
2772   } else {
2773     // ignore
2774   }
2775 
2776   errno = old_errno;
2777 }
2778 
2779 
2780 static int SR_initialize() {
2781   struct sigaction act;
2782   char *s;
2783   // Get signal number to use for suspend/resume
2784   if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2785     int sig = ::strtol(s, 0, 10);
2786     if (sig > MAX2(SIGSEGV, SIGBUS) &&  // See 4355769.
2787         sig < NSIG) {                   // Must be legal signal and fit into sigflags[].
2788       SR_signum = sig;
2789     } else {
2790       warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2791               sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2792     }
2793   }
2794 
2795   assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2796          "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2797 
2798   sigemptyset(&SR_sigset);
2799   sigaddset(&SR_sigset, SR_signum);
2800 
2801   // Set up signal handler for suspend/resume
2802   act.sa_flags = SA_RESTART|SA_SIGINFO;
2803   act.sa_handler = (void (*)(int)) SR_handler;
2804 
2805   // SR_signum is blocked by default.
2806   // 4528190 - We also need to block pthread restart signal (32 on all
2807   // supported Bsd platforms). Note that BsdThreads need to block
2808   // this signal for all threads to work properly. So we don't have
2809   // to use hard-coded signal number when setting up the mask.
2810   pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2811 
2812   if (sigaction(SR_signum, &act, 0) == -1) {
2813     return -1;
2814   }
2815 
2816   // Save signal flag
2817   os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2818   return 0;
2819 }
2820 
2821 static int sr_notify(OSThread* osthread) {
2822   int status = pthread_kill(osthread->pthread_id(), SR_signum);
2823   assert_status(status == 0, status, "pthread_kill");
2824   return status;
2825 }
2826 
2827 // "Randomly" selected value for how long we want to spin
2828 // before bailing out on suspending a thread, also how often
2829 // we send a signal to a thread we want to resume
2830 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2831 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2832 
2833 // returns true on success and false on error - really an error is fatal
2834 // but this seems the normal response to library errors
2835 static bool do_suspend(OSThread* osthread) {
2836   assert(osthread->sr.is_running(), "thread should be running");
2837   assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2838 
2839   // mark as suspended and send signal
2840   if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2841     // failed to switch, state wasn't running?
2842     ShouldNotReachHere();
2843     return false;
2844   }
2845 
2846   if (sr_notify(osthread) != 0) {
2847     ShouldNotReachHere();
2848   }
2849 
2850   // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2851   while (true) {
2852     if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2853       break;
2854     } else {
2855       // timeout
2856       os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2857       if (cancelled == os::SuspendResume::SR_RUNNING) {
2858         return false;
2859       } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2860         // make sure that we consume the signal on the semaphore as well
2861         sr_semaphore.wait();
2862         break;
2863       } else {
2864         ShouldNotReachHere();
2865         return false;
2866       }
2867     }
2868   }
2869 
2870   guarantee(osthread->sr.is_suspended(), "Must be suspended");
2871   return true;
2872 }
2873 
2874 static void do_resume(OSThread* osthread) {
2875   assert(osthread->sr.is_suspended(), "thread should be suspended");
2876   assert(!sr_semaphore.trywait(), "invalid semaphore state");
2877 
2878   if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2879     // failed to switch to WAKEUP_REQUEST
2880     ShouldNotReachHere();
2881     return;
2882   }
2883 
2884   while (true) {
2885     if (sr_notify(osthread) == 0) {
2886       if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2887         if (osthread->sr.is_running()) {
2888           return;
2889         }
2890       }
2891     } else {
2892       ShouldNotReachHere();
2893     }
2894   }
2895 
2896   guarantee(osthread->sr.is_running(), "Must be running!");
2897 }
2898 
2899 ///////////////////////////////////////////////////////////////////////////////////
2900 // signal handling (except suspend/resume)
2901 
2902 // This routine may be used by user applications as a "hook" to catch signals.
2903 // The user-defined signal handler must pass unrecognized signals to this
2904 // routine, and if it returns true (non-zero), then the signal handler must
2905 // return immediately.  If the flag "abort_if_unrecognized" is true, then this
2906 // routine will never retun false (zero), but instead will execute a VM panic
2907 // routine kill the process.
2908 //
2909 // If this routine returns false, it is OK to call it again.  This allows
2910 // the user-defined signal handler to perform checks either before or after
2911 // the VM performs its own checks.  Naturally, the user code would be making
2912 // a serious error if it tried to handle an exception (such as a null check
2913 // or breakpoint) that the VM was generating for its own correct operation.
2914 //
2915 // This routine may recognize any of the following kinds of signals:
2916 //    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2917 // It should be consulted by handlers for any of those signals.
2918 //
2919 // The caller of this routine must pass in the three arguments supplied
2920 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2921 // field of the structure passed to sigaction().  This routine assumes that
2922 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2923 //
2924 // Note that the VM will print warnings if it detects conflicting signal
2925 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2926 //
2927 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2928                                                void* ucontext,
2929                                                int abort_if_unrecognized);
2930 
2931 void signalHandler(int sig, siginfo_t* info, void* uc) {
2932   assert(info != NULL && uc != NULL, "it must be old kernel");
2933   int orig_errno = errno;  // Preserve errno value over signal handler.
2934   JVM_handle_bsd_signal(sig, info, uc, true);
2935   errno = orig_errno;
2936 }
2937 
2938 
2939 // This boolean allows users to forward their own non-matching signals
2940 // to JVM_handle_bsd_signal, harmlessly.
2941 bool os::Bsd::signal_handlers_are_installed = false;
2942 
2943 // For signal-chaining
2944 struct sigaction sigact[NSIG];
2945 uint32_t sigs = 0;
2946 #if (32 < NSIG-1)
2947 #error "Not all signals can be encoded in sigs. Adapt its type!"
2948 #endif
2949 bool os::Bsd::libjsig_is_loaded = false;
2950 typedef struct sigaction *(*get_signal_t)(int);
2951 get_signal_t os::Bsd::get_signal_action = NULL;
2952 
2953 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2954   struct sigaction *actp = NULL;
2955 
2956   if (libjsig_is_loaded) {
2957     // Retrieve the old signal handler from libjsig
2958     actp = (*get_signal_action)(sig);
2959   }
2960   if (actp == NULL) {
2961     // Retrieve the preinstalled signal handler from jvm
2962     actp = get_preinstalled_handler(sig);
2963   }
2964 
2965   return actp;
2966 }
2967 
2968 static bool call_chained_handler(struct sigaction *actp, int sig,
2969                                  siginfo_t *siginfo, void *context) {
2970   // Call the old signal handler
2971   if (actp->sa_handler == SIG_DFL) {
2972     // It's more reasonable to let jvm treat it as an unexpected exception
2973     // instead of taking the default action.
2974     return false;
2975   } else if (actp->sa_handler != SIG_IGN) {
2976     if ((actp->sa_flags & SA_NODEFER) == 0) {
2977       // automaticlly block the signal
2978       sigaddset(&(actp->sa_mask), sig);
2979     }
2980 
2981     sa_handler_t hand;
2982     sa_sigaction_t sa;
2983     bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2984     // retrieve the chained handler
2985     if (siginfo_flag_set) {
2986       sa = actp->sa_sigaction;
2987     } else {
2988       hand = actp->sa_handler;
2989     }
2990 
2991     if ((actp->sa_flags & SA_RESETHAND) != 0) {
2992       actp->sa_handler = SIG_DFL;
2993     }
2994 
2995     // try to honor the signal mask
2996     sigset_t oset;
2997     pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2998 
2999     // call into the chained handler
3000     if (siginfo_flag_set) {
3001       (*sa)(sig, siginfo, context);
3002     } else {
3003       (*hand)(sig);
3004     }
3005 
3006     // restore the signal mask
3007     pthread_sigmask(SIG_SETMASK, &oset, 0);
3008   }
3009   // Tell jvm's signal handler the signal is taken care of.
3010   return true;
3011 }
3012 
3013 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3014   bool chained = false;
3015   // signal-chaining
3016   if (UseSignalChaining) {
3017     struct sigaction *actp = get_chained_signal_action(sig);
3018     if (actp != NULL) {
3019       chained = call_chained_handler(actp, sig, siginfo, context);
3020     }
3021   }
3022   return chained;
3023 }
3024 
3025 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3026   if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
3027     return &sigact[sig];
3028   }
3029   return NULL;
3030 }
3031 
3032 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3033   assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3034   sigact[sig] = oldAct;
3035   sigs |= (uint32_t)1 << (sig-1);
3036 }
3037 
3038 // for diagnostic
3039 int sigflags[NSIG];
3040 
3041 int os::Bsd::get_our_sigflags(int sig) {
3042   assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3043   return sigflags[sig];
3044 }
3045 
3046 void os::Bsd::set_our_sigflags(int sig, int flags) {
3047   assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3048   if (sig > 0 && sig < NSIG) {
3049     sigflags[sig] = flags;
3050   }
3051 }
3052 
3053 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3054   // Check for overwrite.
3055   struct sigaction oldAct;
3056   sigaction(sig, (struct sigaction*)NULL, &oldAct);
3057 
3058   void* oldhand = oldAct.sa_sigaction
3059                 ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
3060                 : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
3061   if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3062       oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3063       oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3064     if (AllowUserSignalHandlers || !set_installed) {
3065       // Do not overwrite; user takes responsibility to forward to us.
3066       return;
3067     } else if (UseSignalChaining) {
3068       // save the old handler in jvm
3069       save_preinstalled_handler(sig, oldAct);
3070       // libjsig also interposes the sigaction() call below and saves the
3071       // old sigaction on it own.
3072     } else {
3073       fatal("Encountered unexpected pre-existing sigaction handler "
3074             "%#lx for signal %d.", (long)oldhand, sig);
3075     }
3076   }
3077 
3078   struct sigaction sigAct;
3079   sigfillset(&(sigAct.sa_mask));
3080   sigAct.sa_handler = SIG_DFL;
3081   if (!set_installed) {
3082     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3083   } else {
3084     sigAct.sa_sigaction = signalHandler;
3085     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3086   }
3087 #ifdef __APPLE__
3088   // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3089   // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3090   // if the signal handler declares it will handle it on alternate stack.
3091   // Notice we only declare we will handle it on alt stack, but we are not
3092   // actually going to use real alt stack - this is just a workaround.
3093   // Please see ux_exception.c, method catch_mach_exception_raise for details
3094   // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3095   if (sig == SIGSEGV) {
3096     sigAct.sa_flags |= SA_ONSTACK;
3097   }
3098 #endif
3099 
3100   // Save flags, which are set by ours
3101   assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3102   sigflags[sig] = sigAct.sa_flags;
3103 
3104   int ret = sigaction(sig, &sigAct, &oldAct);
3105   assert(ret == 0, "check");
3106 
3107   void* oldhand2  = oldAct.sa_sigaction
3108                   ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3109                   : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3110   assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3111 }
3112 
3113 // install signal handlers for signals that HotSpot needs to
3114 // handle in order to support Java-level exception handling.
3115 
3116 void os::Bsd::install_signal_handlers() {
3117   if (!signal_handlers_are_installed) {
3118     signal_handlers_are_installed = true;
3119 
3120     // signal-chaining
3121     typedef void (*signal_setting_t)();
3122     signal_setting_t begin_signal_setting = NULL;
3123     signal_setting_t end_signal_setting = NULL;
3124     begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3125                                           dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3126     if (begin_signal_setting != NULL) {
3127       end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3128                                           dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3129       get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3130                                          dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3131       libjsig_is_loaded = true;
3132       assert(UseSignalChaining, "should enable signal-chaining");
3133     }
3134     if (libjsig_is_loaded) {
3135       // Tell libjsig jvm is setting signal handlers
3136       (*begin_signal_setting)();
3137     }
3138 
3139     set_signal_handler(SIGSEGV, true);
3140     set_signal_handler(SIGPIPE, true);
3141     set_signal_handler(SIGBUS, true);
3142     set_signal_handler(SIGILL, true);
3143     set_signal_handler(SIGFPE, true);
3144     set_signal_handler(SIGXFSZ, true);
3145 
3146 #if defined(__APPLE__)
3147     // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3148     // signals caught and handled by the JVM. To work around this, we reset the mach task
3149     // signal handler that's placed on our process by CrashReporter. This disables
3150     // CrashReporter-based reporting.
3151     //
3152     // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3153     // on caught fatal signals.
3154     //
3155     // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3156     // handlers. By replacing the existing task exception handler, we disable gdb's mach
3157     // exception handling, while leaving the standard BSD signal handlers functional.
3158     kern_return_t kr;
3159     kr = task_set_exception_ports(mach_task_self(),
3160                                   EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3161                                   MACH_PORT_NULL,
3162                                   EXCEPTION_STATE_IDENTITY,
3163                                   MACHINE_THREAD_STATE);
3164 
3165     assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3166 #endif
3167 
3168     if (libjsig_is_loaded) {
3169       // Tell libjsig jvm finishes setting signal handlers
3170       (*end_signal_setting)();
3171     }
3172 
3173     // We don't activate signal checker if libjsig is in place, we trust ourselves
3174     // and if UserSignalHandler is installed all bets are off
3175     if (CheckJNICalls) {
3176       if (libjsig_is_loaded) {
3177         if (PrintJNIResolving) {
3178           tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3179         }
3180         check_signals = false;
3181       }
3182       if (AllowUserSignalHandlers) {
3183         if (PrintJNIResolving) {
3184           tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3185         }
3186         check_signals = false;
3187       }
3188     }
3189   }
3190 }
3191 
3192 
3193 /////
3194 // glibc on Bsd platform uses non-documented flag
3195 // to indicate, that some special sort of signal
3196 // trampoline is used.
3197 // We will never set this flag, and we should
3198 // ignore this flag in our diagnostic
3199 #ifdef SIGNIFICANT_SIGNAL_MASK
3200   #undef SIGNIFICANT_SIGNAL_MASK
3201 #endif
3202 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3203 
3204 static const char* get_signal_handler_name(address handler,
3205                                            char* buf, int buflen) {
3206   int offset;
3207   bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3208   if (found) {
3209     // skip directory names
3210     const char *p1, *p2;
3211     p1 = buf;
3212     size_t len = strlen(os::file_separator());
3213     while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3214     jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3215   } else {
3216     jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3217   }
3218   return buf;
3219 }
3220 
3221 static void print_signal_handler(outputStream* st, int sig,
3222                                  char* buf, size_t buflen) {
3223   struct sigaction sa;
3224 
3225   sigaction(sig, NULL, &sa);
3226 
3227   // See comment for SIGNIFICANT_SIGNAL_MASK define
3228   sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3229 
3230   st->print("%s: ", os::exception_name(sig, buf, buflen));
3231 
3232   address handler = (sa.sa_flags & SA_SIGINFO)
3233     ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3234     : CAST_FROM_FN_PTR(address, sa.sa_handler);
3235 
3236   if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3237     st->print("SIG_DFL");
3238   } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3239     st->print("SIG_IGN");
3240   } else {
3241     st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3242   }
3243 
3244   st->print(", sa_mask[0]=");
3245   os::Posix::print_signal_set_short(st, &sa.sa_mask);
3246 
3247   address rh = VMError::get_resetted_sighandler(sig);
3248   // May be, handler was resetted by VMError?
3249   if (rh != NULL) {
3250     handler = rh;
3251     sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3252   }
3253 
3254   st->print(", sa_flags=");
3255   os::Posix::print_sa_flags(st, sa.sa_flags);
3256 
3257   // Check: is it our handler?
3258   if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3259       handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3260     // It is our signal handler
3261     // check for flags, reset system-used one!
3262     if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3263       st->print(
3264                 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3265                 os::Bsd::get_our_sigflags(sig));
3266     }
3267   }
3268   st->cr();
3269 }
3270 
3271 
3272 #define DO_SIGNAL_CHECK(sig)                      \
3273   do {                                            \
3274     if (!sigismember(&check_signal_done, sig)) {  \
3275       os::Bsd::check_signal_handler(sig);         \
3276     }                                             \
3277   } while (0)
3278 
3279 // This method is a periodic task to check for misbehaving JNI applications
3280 // under CheckJNI, we can add any periodic checks here
3281 
3282 void os::run_periodic_checks() {
3283 
3284   if (check_signals == false) return;
3285 
3286   // SEGV and BUS if overridden could potentially prevent
3287   // generation of hs*.log in the event of a crash, debugging
3288   // such a case can be very challenging, so we absolutely
3289   // check the following for a good measure:
3290   DO_SIGNAL_CHECK(SIGSEGV);
3291   DO_SIGNAL_CHECK(SIGILL);
3292   DO_SIGNAL_CHECK(SIGFPE);
3293   DO_SIGNAL_CHECK(SIGBUS);
3294   DO_SIGNAL_CHECK(SIGPIPE);
3295   DO_SIGNAL_CHECK(SIGXFSZ);
3296 
3297 
3298   // ReduceSignalUsage allows the user to override these handlers
3299   // see comments at the very top and jvm_solaris.h
3300   if (!ReduceSignalUsage) {
3301     DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3302     DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3303     DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3304     DO_SIGNAL_CHECK(BREAK_SIGNAL);
3305   }
3306 
3307   DO_SIGNAL_CHECK(SR_signum);
3308 }
3309 
3310 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3311 
3312 static os_sigaction_t os_sigaction = NULL;
3313 
3314 void os::Bsd::check_signal_handler(int sig) {
3315   char buf[O_BUFLEN];
3316   address jvmHandler = NULL;
3317 
3318 
3319   struct sigaction act;
3320   if (os_sigaction == NULL) {
3321     // only trust the default sigaction, in case it has been interposed
3322     os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3323     if (os_sigaction == NULL) return;
3324   }
3325 
3326   os_sigaction(sig, (struct sigaction*)NULL, &act);
3327 
3328 
3329   act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3330 
3331   address thisHandler = (act.sa_flags & SA_SIGINFO)
3332     ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3333     : CAST_FROM_FN_PTR(address, act.sa_handler);
3334 
3335 
3336   switch (sig) {
3337   case SIGSEGV:
3338   case SIGBUS:
3339   case SIGFPE:
3340   case SIGPIPE:
3341   case SIGILL:
3342   case SIGXFSZ:
3343     jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3344     break;
3345 
3346   case SHUTDOWN1_SIGNAL:
3347   case SHUTDOWN2_SIGNAL:
3348   case SHUTDOWN3_SIGNAL:
3349   case BREAK_SIGNAL:
3350     jvmHandler = (address)user_handler();
3351     break;
3352 
3353   default:
3354     if (sig == SR_signum) {
3355       jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3356     } else {
3357       return;
3358     }
3359     break;
3360   }
3361 
3362   if (thisHandler != jvmHandler) {
3363     tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3364     tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3365     tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3366     // No need to check this sig any longer
3367     sigaddset(&check_signal_done, sig);
3368     // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3369     if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3370       tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3371                     exception_name(sig, buf, O_BUFLEN));
3372     }
3373   } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3374     tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3375     tty->print("expected:");
3376     os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3377     tty->cr();
3378     tty->print("  found:");
3379     os::Posix::print_sa_flags(tty, act.sa_flags);
3380     tty->cr();
3381     // No need to check this sig any longer
3382     sigaddset(&check_signal_done, sig);
3383   }
3384 
3385   // Dump all the signal
3386   if (sigismember(&check_signal_done, sig)) {
3387     print_signal_handlers(tty, buf, O_BUFLEN);
3388   }
3389 }
3390 
3391 extern void report_error(char* file_name, int line_no, char* title,
3392                          char* format, ...);
3393 
3394 // this is called _before_ the most of global arguments have been parsed
3395 void os::init(void) {
3396   char dummy;   // used to get a guess on initial stack address
3397 
3398   // With BsdThreads the JavaMain thread pid (primordial thread)
3399   // is different than the pid of the java launcher thread.
3400   // So, on Bsd, the launcher thread pid is passed to the VM
3401   // via the sun.java.launcher.pid property.
3402   // Use this property instead of getpid() if it was correctly passed.
3403   // See bug 6351349.
3404   pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3405 
3406   _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3407 
3408   clock_tics_per_sec = CLK_TCK;
3409 
3410   init_random(1234567);
3411 
3412   ThreadCritical::initialize();
3413 
3414   Bsd::set_page_size(getpagesize());
3415   if (Bsd::page_size() == -1) {
3416     fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3417   }
3418   init_page_sizes((size_t) Bsd::page_size());
3419 
3420   Bsd::initialize_system_info();
3421 
3422   // main_thread points to the aboriginal thread
3423   Bsd::_main_thread = pthread_self();
3424 
3425   Bsd::clock_init();
3426   initial_time_count = javaTimeNanos();
3427 
3428 #ifdef __APPLE__
3429   // XXXDARWIN
3430   // Work around the unaligned VM callbacks in hotspot's
3431   // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3432   // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3433   // alignment when doing symbol lookup. To work around this, we force early
3434   // binding of all symbols now, thus binding when alignment is known-good.
3435   _dyld_bind_fully_image_containing_address((const void *) &os::init);
3436 #endif
3437 
3438   os::Posix::init();
3439 }
3440 
3441 // To install functions for atexit system call
3442 extern "C" {
3443   static void perfMemory_exit_helper() {
3444     perfMemory_exit();
3445   }
3446 }
3447 
3448 // this is called _after_ the global arguments have been parsed
3449 jint os::init_2(void) {
3450 
3451   os::Posix::init_2();
3452 
3453   // Allocate a single page and mark it as readable for safepoint polling
3454   address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3455   guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3456 
3457   os::set_polling_page(polling_page);
3458   log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3459 
3460   if (!UseMembar) {
3461     address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3462     guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3463     os::set_memory_serialize_page(mem_serialize_page);
3464     log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3465   }
3466 
3467   // initialize suspend/resume support - must do this before signal_sets_init()
3468   if (SR_initialize() != 0) {
3469     perror("SR_initialize failed");
3470     return JNI_ERR;
3471   }
3472 
3473   Bsd::signal_sets_init();
3474   Bsd::install_signal_handlers();
3475 
3476   // Check and sets minimum stack sizes against command line options
3477   if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3478     return JNI_ERR;
3479   }
3480 
3481   if (MaxFDLimit) {
3482     // set the number of file descriptors to max. print out error
3483     // if getrlimit/setrlimit fails but continue regardless.
3484     struct rlimit nbr_files;
3485     int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3486     if (status != 0) {
3487       log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3488     } else {
3489       nbr_files.rlim_cur = nbr_files.rlim_max;
3490 
3491 #ifdef __APPLE__
3492       // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3493       // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3494       // be used instead
3495       nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3496 #endif
3497 
3498       status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3499       if (status != 0) {
3500         log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3501       }
3502     }
3503   }
3504 
3505   // at-exit methods are called in the reverse order of their registration.
3506   // atexit functions are called on return from main or as a result of a
3507   // call to exit(3C). There can be only 32 of these functions registered
3508   // and atexit() does not set errno.
3509 
3510   if (PerfAllowAtExitRegistration) {
3511     // only register atexit functions if PerfAllowAtExitRegistration is set.
3512     // atexit functions can be delayed until process exit time, which
3513     // can be problematic for embedded VM situations. Embedded VMs should
3514     // call DestroyJavaVM() to assure that VM resources are released.
3515 
3516     // note: perfMemory_exit_helper atexit function may be removed in
3517     // the future if the appropriate cleanup code can be added to the
3518     // VM_Exit VMOperation's doit method.
3519     if (atexit(perfMemory_exit_helper) != 0) {
3520       warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3521     }
3522   }
3523 
3524   // initialize thread priority policy
3525   prio_init();
3526 
3527 #ifdef __APPLE__
3528   // dynamically link to objective c gc registration
3529   void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3530   if (handleLibObjc != NULL) {
3531     objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3532   }
3533 #endif
3534 
3535   return JNI_OK;
3536 }
3537 
3538 // Mark the polling page as unreadable
3539 void os::make_polling_page_unreadable(void) {
3540   if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3541     fatal("Could not disable polling page");
3542   }
3543 }
3544 
3545 // Mark the polling page as readable
3546 void os::make_polling_page_readable(void) {
3547   if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3548     fatal("Could not enable polling page");
3549   }
3550 }
3551 
3552 int os::active_processor_count() {
3553   return _processor_count;
3554 }
3555 
3556 void os::set_native_thread_name(const char *name) {
3557 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3558   // This is only supported in Snow Leopard and beyond
3559   if (name != NULL) {
3560     // Add a "Java: " prefix to the name
3561     char buf[MAXTHREADNAMESIZE];
3562     snprintf(buf, sizeof(buf), "Java: %s", name);
3563     pthread_setname_np(buf);
3564   }
3565 #endif
3566 }
3567 
3568 bool os::distribute_processes(uint length, uint* distribution) {
3569   // Not yet implemented.
3570   return false;
3571 }
3572 
3573 bool os::bind_to_processor(uint processor_id) {
3574   // Not yet implemented.
3575   return false;
3576 }
3577 
3578 void os::SuspendedThreadTask::internal_do_task() {
3579   if (do_suspend(_thread->osthread())) {
3580     SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3581     do_task(context);
3582     do_resume(_thread->osthread());
3583   }
3584 }
3585 
3586 ///
3587 class PcFetcher : public os::SuspendedThreadTask {
3588  public:
3589   PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3590   ExtendedPC result();
3591  protected:
3592   void do_task(const os::SuspendedThreadTaskContext& context);
3593  private:
3594   ExtendedPC _epc;
3595 };
3596 
3597 ExtendedPC PcFetcher::result() {
3598   guarantee(is_done(), "task is not done yet.");
3599   return _epc;
3600 }
3601 
3602 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3603   Thread* thread = context.thread();
3604   OSThread* osthread = thread->osthread();
3605   if (osthread->ucontext() != NULL) {
3606     _epc = os::Bsd::ucontext_get_pc((const ucontext_t *) context.ucontext());
3607   } else {
3608     // NULL context is unexpected, double-check this is the VMThread
3609     guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3610   }
3611 }
3612 
3613 // Suspends the target using the signal mechanism and then grabs the PC before
3614 // resuming the target. Used by the flat-profiler only
3615 ExtendedPC os::get_thread_pc(Thread* thread) {
3616   // Make sure that it is called by the watcher for the VMThread
3617   assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3618   assert(thread->is_VM_thread(), "Can only be called for VMThread");
3619 
3620   PcFetcher fetcher(thread);
3621   fetcher.run();
3622   return fetcher.result();
3623 }
3624 
3625 ////////////////////////////////////////////////////////////////////////////////
3626 // debug support
3627 
3628 bool os::find(address addr, outputStream* st) {
3629   Dl_info dlinfo;
3630   memset(&dlinfo, 0, sizeof(dlinfo));
3631   if (dladdr(addr, &dlinfo) != 0) {
3632     st->print(PTR_FORMAT ": ", addr);
3633     if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3634       st->print("%s+%#x", dlinfo.dli_sname,
3635                 addr - (intptr_t)dlinfo.dli_saddr);
3636     } else if (dlinfo.dli_fbase != NULL) {
3637       st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3638     } else {
3639       st->print("<absolute address>");
3640     }
3641     if (dlinfo.dli_fname != NULL) {
3642       st->print(" in %s", dlinfo.dli_fname);
3643     }
3644     if (dlinfo.dli_fbase != NULL) {
3645       st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3646     }
3647     st->cr();
3648 
3649     if (Verbose) {
3650       // decode some bytes around the PC
3651       address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3652       address end   = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3653       address       lowest = (address) dlinfo.dli_sname;
3654       if (!lowest)  lowest = (address) dlinfo.dli_fbase;
3655       if (begin < lowest)  begin = lowest;
3656       Dl_info dlinfo2;
3657       if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3658           && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3659         end = (address) dlinfo2.dli_saddr;
3660       }
3661       Disassembler::decode(begin, end, st);
3662     }
3663     return true;
3664   }
3665   return false;
3666 }
3667 
3668 ////////////////////////////////////////////////////////////////////////////////
3669 // misc
3670 
3671 // This does not do anything on Bsd. This is basically a hook for being
3672 // able to use structured exception handling (thread-local exception filters)
3673 // on, e.g., Win32.
3674 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3675                               const methodHandle& method, JavaCallArguments* args,
3676                               Thread* thread) {
3677   f(value, method, args, thread);
3678 }
3679 
3680 void os::print_statistics() {
3681 }
3682 
3683 bool os::message_box(const char* title, const char* message) {
3684   int i;
3685   fdStream err(defaultStream::error_fd());
3686   for (i = 0; i < 78; i++) err.print_raw("=");
3687   err.cr();
3688   err.print_raw_cr(title);
3689   for (i = 0; i < 78; i++) err.print_raw("-");
3690   err.cr();
3691   err.print_raw_cr(message);
3692   for (i = 0; i < 78; i++) err.print_raw("=");
3693   err.cr();
3694 
3695   char buf[16];
3696   // Prevent process from exiting upon "read error" without consuming all CPU
3697   while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3698 
3699   return buf[0] == 'y' || buf[0] == 'Y';
3700 }
3701 
3702 int os::stat(const char *path, struct stat *sbuf) {
3703   char pathbuf[MAX_PATH];
3704   if (strlen(path) > MAX_PATH - 1) {
3705     errno = ENAMETOOLONG;
3706     return -1;
3707   }
3708   os::native_path(strcpy(pathbuf, path));
3709   return ::stat(pathbuf, sbuf);
3710 }
3711 
3712 static inline struct timespec get_mtime(const char* filename) {
3713   struct stat st;
3714   int ret = os::stat(filename, &st);
3715   assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
3716 #ifdef __APPLE__
3717   return st.st_mtimespec;
3718 #else
3719   return st.st_mtim;
3720 #endif
3721 }
3722 
3723 int os::compare_file_modified_times(const char* file1, const char* file2) {
3724   struct timespec filetime1 = get_mtime(file1);
3725   struct timespec filetime2 = get_mtime(file2);
3726   int diff = filetime1.tv_sec - filetime2.tv_sec;
3727   if (diff == 0) {
3728     return filetime1.tv_nsec - filetime2.tv_nsec;
3729   }
3730   return diff;
3731 }
3732 
3733 // Is a (classpath) directory empty?
3734 bool os::dir_is_empty(const char* path) {
3735   DIR *dir = NULL;
3736   struct dirent *ptr;
3737 
3738   dir = opendir(path);
3739   if (dir == NULL) return true;
3740 
3741   // Scan the directory
3742   bool result = true;
3743   char buf[sizeof(struct dirent) + MAX_PATH];
3744   while (result && (ptr = ::readdir(dir)) != NULL) {
3745     if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3746       result = false;
3747     }
3748   }
3749   closedir(dir);
3750   return result;
3751 }
3752 
3753 // This code originates from JDK's sysOpen and open64_w
3754 // from src/solaris/hpi/src/system_md.c
3755 
3756 int os::open(const char *path, int oflag, int mode) {
3757   if (strlen(path) > MAX_PATH - 1) {
3758     errno = ENAMETOOLONG;
3759     return -1;
3760   }
3761   int fd;
3762 
3763   fd = ::open(path, oflag, mode);
3764   if (fd == -1) return -1;
3765 
3766   // If the open succeeded, the file might still be a directory
3767   {
3768     struct stat buf;
3769     int ret = ::fstat(fd, &buf);
3770     int st_mode = buf.st_mode;
3771 
3772     if (ret != -1) {
3773       if ((st_mode & S_IFMT) == S_IFDIR) {
3774         errno = EISDIR;
3775         ::close(fd);
3776         return -1;
3777       }
3778     } else {
3779       ::close(fd);
3780       return -1;
3781     }
3782   }
3783 
3784   // All file descriptors that are opened in the JVM and not
3785   // specifically destined for a subprocess should have the
3786   // close-on-exec flag set.  If we don't set it, then careless 3rd
3787   // party native code might fork and exec without closing all
3788   // appropriate file descriptors (e.g. as we do in closeDescriptors in
3789   // UNIXProcess.c), and this in turn might:
3790   //
3791   // - cause end-of-file to fail to be detected on some file
3792   //   descriptors, resulting in mysterious hangs, or
3793   //
3794   // - might cause an fopen in the subprocess to fail on a system
3795   //   suffering from bug 1085341.
3796   //
3797   // (Yes, the default setting of the close-on-exec flag is a Unix
3798   // design flaw)
3799   //
3800   // See:
3801   // 1085341: 32-bit stdio routines should support file descriptors >255
3802   // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3803   // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3804   //
3805 #ifdef FD_CLOEXEC
3806   {
3807     int flags = ::fcntl(fd, F_GETFD);
3808     if (flags != -1) {
3809       ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3810     }
3811   }
3812 #endif
3813 
3814   return fd;
3815 }
3816 
3817 
3818 // create binary file, rewriting existing file if required
3819 int os::create_binary_file(const char* path, bool rewrite_existing) {
3820   int oflags = O_WRONLY | O_CREAT;
3821   if (!rewrite_existing) {
3822     oflags |= O_EXCL;
3823   }
3824   return ::open(path, oflags, S_IREAD | S_IWRITE);
3825 }
3826 
3827 // return current position of file pointer
3828 jlong os::current_file_offset(int fd) {
3829   return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3830 }
3831 
3832 // move file pointer to the specified offset
3833 jlong os::seek_to_file_offset(int fd, jlong offset) {
3834   return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3835 }
3836 
3837 // This code originates from JDK's sysAvailable
3838 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3839 
3840 int os::available(int fd, jlong *bytes) {
3841   jlong cur, end;
3842   int mode;
3843   struct stat buf;
3844 
3845   if (::fstat(fd, &buf) >= 0) {
3846     mode = buf.st_mode;
3847     if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3848       int n;
3849       if (::ioctl(fd, FIONREAD, &n) >= 0) {
3850         *bytes = n;
3851         return 1;
3852       }
3853     }
3854   }
3855   if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3856     return 0;
3857   } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3858     return 0;
3859   } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3860     return 0;
3861   }
3862   *bytes = end - cur;
3863   return 1;
3864 }
3865 
3866 // Map a block of memory.
3867 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3868                         char *addr, size_t bytes, bool read_only,
3869                         bool allow_exec) {
3870   int prot;
3871   int flags;
3872 
3873   if (read_only) {
3874     prot = PROT_READ;
3875     flags = MAP_SHARED;
3876   } else {
3877     prot = PROT_READ | PROT_WRITE;
3878     flags = MAP_PRIVATE;
3879   }
3880 
3881   if (allow_exec) {
3882     prot |= PROT_EXEC;
3883   }
3884 
3885   if (addr != NULL) {
3886     flags |= MAP_FIXED;
3887   }
3888 
3889   char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3890                                      fd, file_offset);
3891   if (mapped_address == MAP_FAILED) {
3892     return NULL;
3893   }
3894   return mapped_address;
3895 }
3896 
3897 
3898 // Remap a block of memory.
3899 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3900                           char *addr, size_t bytes, bool read_only,
3901                           bool allow_exec) {
3902   // same as map_memory() on this OS
3903   return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3904                         allow_exec);
3905 }
3906 
3907 
3908 // Unmap a block of memory.
3909 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3910   return munmap(addr, bytes) == 0;
3911 }
3912 
3913 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3914 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3915 // of a thread.
3916 //
3917 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3918 // the fast estimate available on the platform.
3919 
3920 jlong os::current_thread_cpu_time() {
3921 #ifdef __APPLE__
3922   return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3923 #else
3924   Unimplemented();
3925   return 0;
3926 #endif
3927 }
3928 
3929 jlong os::thread_cpu_time(Thread* thread) {
3930 #ifdef __APPLE__
3931   return os::thread_cpu_time(thread, true /* user + sys */);
3932 #else
3933   Unimplemented();
3934   return 0;
3935 #endif
3936 }
3937 
3938 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3939 #ifdef __APPLE__
3940   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3941 #else
3942   Unimplemented();
3943   return 0;
3944 #endif
3945 }
3946 
3947 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3948 #ifdef __APPLE__
3949   struct thread_basic_info tinfo;
3950   mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3951   kern_return_t kr;
3952   thread_t mach_thread;
3953 
3954   mach_thread = thread->osthread()->thread_id();
3955   kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3956   if (kr != KERN_SUCCESS) {
3957     return -1;
3958   }
3959 
3960   if (user_sys_cpu_time) {
3961     jlong nanos;
3962     nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3963     nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3964     return nanos;
3965   } else {
3966     return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3967   }
3968 #else
3969   Unimplemented();
3970   return 0;
3971 #endif
3972 }
3973 
3974 
3975 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3976   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3977   info_ptr->may_skip_backward = false;     // elapsed time not wall time
3978   info_ptr->may_skip_forward = false;      // elapsed time not wall time
3979   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3980 }
3981 
3982 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3983   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3984   info_ptr->may_skip_backward = false;     // elapsed time not wall time
3985   info_ptr->may_skip_forward = false;      // elapsed time not wall time
3986   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3987 }
3988 
3989 bool os::is_thread_cpu_time_supported() {
3990 #ifdef __APPLE__
3991   return true;
3992 #else
3993   return false;
3994 #endif
3995 }
3996 
3997 // System loadavg support.  Returns -1 if load average cannot be obtained.
3998 // Bsd doesn't yet have a (official) notion of processor sets,
3999 // so just return the system wide load average.
4000 int os::loadavg(double loadavg[], int nelem) {
4001   return ::getloadavg(loadavg, nelem);
4002 }
4003 
4004 void os::pause() {
4005   char filename[MAX_PATH];
4006   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4007     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4008   } else {
4009     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4010   }
4011 
4012   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4013   if (fd != -1) {
4014     struct stat buf;
4015     ::close(fd);
4016     while (::stat(filename, &buf) == 0) {
4017       (void)::poll(NULL, 0, 100);
4018     }
4019   } else {
4020     jio_fprintf(stderr,
4021                 "Could not open pause file '%s', continuing immediately.\n", filename);
4022   }
4023 }
4024 
4025 // Darwin has no "environ" in a dynamic library.
4026 #ifdef __APPLE__
4027   #include <crt_externs.h>
4028   #define environ (*_NSGetEnviron())
4029 #else
4030 extern char** environ;
4031 #endif
4032 
4033 // Run the specified command in a separate process. Return its exit value,
4034 // or -1 on failure (e.g. can't fork a new process).
4035 // Unlike system(), this function can be called from signal handler. It
4036 // doesn't block SIGINT et al.
4037 int os::fork_and_exec(char* cmd) {
4038   const char * argv[4] = {"sh", "-c", cmd, NULL};
4039 
4040   // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4041   // pthread_atfork handlers and reset pthread library. All we need is a
4042   // separate process to execve. Make a direct syscall to fork process.
4043   // On IA64 there's no fork syscall, we have to use fork() and hope for
4044   // the best...
4045   pid_t pid = fork();
4046 
4047   if (pid < 0) {
4048     // fork failed
4049     return -1;
4050 
4051   } else if (pid == 0) {
4052     // child process
4053 
4054     // execve() in BsdThreads will call pthread_kill_other_threads_np()
4055     // first to kill every thread on the thread list. Because this list is
4056     // not reset by fork() (see notes above), execve() will instead kill
4057     // every thread in the parent process. We know this is the only thread
4058     // in the new process, so make a system call directly.
4059     // IA64 should use normal execve() from glibc to match the glibc fork()
4060     // above.
4061     execve("/bin/sh", (char* const*)argv, environ);
4062 
4063     // execve failed
4064     _exit(-1);
4065 
4066   } else  {
4067     // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4068     // care about the actual exit code, for now.
4069 
4070     int status;
4071 
4072     // Wait for the child process to exit.  This returns immediately if
4073     // the child has already exited. */
4074     while (waitpid(pid, &status, 0) < 0) {
4075       switch (errno) {
4076       case ECHILD: return 0;
4077       case EINTR: break;
4078       default: return -1;
4079       }
4080     }
4081 
4082     if (WIFEXITED(status)) {
4083       // The child exited normally; get its exit code.
4084       return WEXITSTATUS(status);
4085     } else if (WIFSIGNALED(status)) {
4086       // The child exited because of a signal
4087       // The best value to return is 0x80 + signal number,
4088       // because that is what all Unix shells do, and because
4089       // it allows callers to distinguish between process exit and
4090       // process death by signal.
4091       return 0x80 + WTERMSIG(status);
4092     } else {
4093       // Unknown exit code; pass it through
4094       return status;
4095     }
4096   }
4097 }
4098 
4099 // is_headless_jre()
4100 //
4101 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4102 // in order to report if we are running in a headless jre
4103 //
4104 // Since JDK8 xawt/libmawt.so was moved into the same directory
4105 // as libawt.so, and renamed libawt_xawt.so
4106 //
4107 bool os::is_headless_jre() {
4108 #ifdef __APPLE__
4109   // We no longer build headless-only on Mac OS X
4110   return false;
4111 #else
4112   struct stat statbuf;
4113   char buf[MAXPATHLEN];
4114   char libmawtpath[MAXPATHLEN];
4115   const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
4116   const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4117   char *p;
4118 
4119   // Get path to libjvm.so
4120   os::jvm_path(buf, sizeof(buf));
4121 
4122   // Get rid of libjvm.so
4123   p = strrchr(buf, '/');
4124   if (p == NULL) {
4125     return false;
4126   } else {
4127     *p = '\0';
4128   }
4129 
4130   // Get rid of client or server
4131   p = strrchr(buf, '/');
4132   if (p == NULL) {
4133     return false;
4134   } else {
4135     *p = '\0';
4136   }
4137 
4138   // check xawt/libmawt.so
4139   strcpy(libmawtpath, buf);
4140   strcat(libmawtpath, xawtstr);
4141   if (::stat(libmawtpath, &statbuf) == 0) return false;
4142 
4143   // check libawt_xawt.so
4144   strcpy(libmawtpath, buf);
4145   strcat(libmawtpath, new_xawtstr);
4146   if (::stat(libmawtpath, &statbuf) == 0) return false;
4147 
4148   return true;
4149 #endif
4150 }
4151 
4152 // Get the default path to the core file
4153 // Returns the length of the string
4154 int os::get_core_path(char* buffer, size_t bufferSize) {
4155   int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4156 
4157   // Truncate if theoretical string was longer than bufferSize
4158   n = MIN2(n, (int)bufferSize);
4159 
4160   return n;
4161 }
4162 
4163 #ifndef PRODUCT
4164 void TestReserveMemorySpecial_test() {
4165   // No tests available for this platform
4166 }
4167 #endif
4168 
4169 bool os::start_debugging(char *buf, int buflen) {
4170   int len = (int)strlen(buf);
4171   char *p = &buf[len];
4172 
4173   jio_snprintf(p, buflen-len,
4174              "\n\n"
4175              "Do you want to debug the problem?\n\n"
4176              "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
4177              "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
4178              "Otherwise, press RETURN to abort...",
4179              os::current_process_id(), os::current_process_id(),
4180              os::current_thread_id(), os::current_thread_id());
4181 
4182   bool yes = os::message_box("Unexpected Error", buf);
4183 
4184   if (yes) {
4185     // yes, user asked VM to launch debugger
4186     jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
4187                      os::current_process_id(), os::current_process_id());
4188 
4189     os::fork_and_exec(buf);
4190     yes = false;
4191   }
4192   return yes;
4193 }