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