1 /*
   2  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 // no precompiled headers
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "classfile/vmSymbols.hpp"
  29 #include "code/icBuffer.hpp"
  30 #include "code/vtableStubs.hpp"
  31 #include "compiler/compileBroker.hpp"
  32 #include "compiler/disassembler.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "jvm_bsd.h"
  35 #include "memory/allocation.inline.hpp"
  36 #include "memory/filemap.hpp"
  37 #include "mutex_bsd.inline.hpp"
  38 #include "oops/oop.inline.hpp"
  39 #include "os_share_bsd.hpp"
  40 #include "prims/jniFastGetField.hpp"
  41 #include "prims/jvm.h"
  42 #include "prims/jvm_misc.hpp"
  43 #include "runtime/arguments.hpp"
  44 #include "runtime/extendedPC.hpp"
  45 #include "runtime/globals.hpp"
  46 #include "runtime/interfaceSupport.hpp"
  47 #include "runtime/java.hpp"
  48 #include "runtime/javaCalls.hpp"
  49 #include "runtime/mutexLocker.hpp"
  50 #include "runtime/objectMonitor.hpp"
  51 #include "runtime/osThread.hpp"
  52 #include "runtime/perfMemory.hpp"
  53 #include "runtime/sharedRuntime.hpp"
  54 #include "runtime/statSampler.hpp"
  55 #include "runtime/stubRoutines.hpp"
  56 #include "runtime/thread.inline.hpp"
  57 #include "runtime/threadCritical.hpp"
  58 #include "runtime/timer.hpp"
  59 #include "services/attachListener.hpp"
  60 #include "services/runtimeService.hpp"
  61 #include "utilities/decoder.hpp"
  62 #include "utilities/defaultStream.hpp"
  63 #include "utilities/events.hpp"
  64 #include "utilities/growableArray.hpp"
  65 #include "utilities/vmError.hpp"
  66 
  67 // put OS-includes here
  68 # include <sys/types.h>
  69 # include <sys/mman.h>
  70 # include <sys/stat.h>
  71 # include <sys/select.h>
  72 # include <pthread.h>
  73 # include <signal.h>
  74 # include <errno.h>
  75 # include <dlfcn.h>
  76 # include <stdio.h>
  77 # include <unistd.h>
  78 # include <sys/resource.h>
  79 # include <pthread.h>
  80 # include <sys/stat.h>
  81 # include <sys/time.h>
  82 # include <sys/times.h>
  83 # include <sys/utsname.h>
  84 # include <sys/socket.h>
  85 # include <sys/wait.h>
  86 # include <time.h>
  87 # include <pwd.h>
  88 # include <poll.h>
  89 # include <semaphore.h>
  90 # include <fcntl.h>
  91 # include <string.h>
  92 # include <sys/param.h>
  93 # include <sys/sysctl.h>
  94 # include <sys/ipc.h>
  95 # include <sys/shm.h>
  96 #ifndef __APPLE__
  97 # include <link.h>
  98 #endif
  99 # include <stdint.h>
 100 # include <inttypes.h>
 101 # include <sys/ioctl.h>
 102 
 103 #if defined(__FreeBSD__) || defined(__NetBSD__)
 104 # include <elf.h>
 105 #endif
 106 
 107 #ifdef __APPLE__
 108 # include <mach/mach.h> // semaphore_* API
 109 # include <mach-o/dyld.h>
 110 # include <sys/proc_info.h>
 111 # include <objc/objc-auto.h>
 112 #endif
 113 
 114 #ifndef MAP_ANONYMOUS
 115 #define MAP_ANONYMOUS MAP_ANON
 116 #endif
 117 
 118 #define MAX_PATH    (2 * K)
 119 
 120 // for timer info max values which include all bits
 121 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
 122 
 123 #define LARGEPAGES_BIT (1 << 6)
 124 ////////////////////////////////////////////////////////////////////////////////
 125 // global variables
 126 julong os::Bsd::_physical_memory = 0;
 127 
 128 
 129 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
 130 pthread_t os::Bsd::_main_thread;
 131 int os::Bsd::_page_size = -1;
 132 
 133 static jlong initial_time_count=0;
 134 
 135 static int clock_tics_per_sec = 100;
 136 
 137 // For diagnostics to print a message once. see run_periodic_checks
 138 static sigset_t check_signal_done;
 139 static bool check_signals = true;
 140 
 141 static pid_t _initial_pid = 0;
 142 
 143 /* Signal number used to suspend/resume a thread */
 144 
 145 /* do not use any signal number less than SIGSEGV, see 4355769 */
 146 static int SR_signum = SIGUSR2;
 147 sigset_t SR_sigset;
 148 
 149 
 150 ////////////////////////////////////////////////////////////////////////////////
 151 // utility functions
 152 
 153 static int SR_initialize();
 154 static int SR_finalize();
 155 
 156 julong os::available_memory() {
 157   return Bsd::available_memory();
 158 }
 159 
 160 julong os::Bsd::available_memory() {
 161   // XXXBSD: this is just a stopgap implementation
 162   return physical_memory() >> 2;
 163 }
 164 
 165 julong os::physical_memory() {
 166   return Bsd::physical_memory();
 167 }
 168 
 169 julong os::allocatable_physical_memory(julong size) {
 170 #ifdef _LP64
 171   return size;
 172 #else
 173   julong result = MIN2(size, (julong)3800*M);
 174    if (!is_allocatable(result)) {
 175      // See comments under solaris for alignment considerations
 176      julong reasonable_size = (julong)2*G - 2 * os::vm_page_size();
 177      result =  MIN2(size, reasonable_size);
 178    }
 179    return result;
 180 #endif // _LP64
 181 }
 182 
 183 ////////////////////////////////////////////////////////////////////////////////
 184 // environment support
 185 
 186 bool os::getenv(const char* name, char* buf, int len) {
 187   const char* val = ::getenv(name);
 188   if (val != NULL && strlen(val) < (size_t)len) {
 189     strcpy(buf, val);
 190     return true;
 191   }
 192   if (len > 0) buf[0] = 0;  // return a null string
 193   return false;
 194 }
 195 
 196 
 197 // Return true if user is running as root.
 198 
 199 bool os::have_special_privileges() {
 200   static bool init = false;
 201   static bool privileges = false;
 202   if (!init) {
 203     privileges = (getuid() != geteuid()) || (getgid() != getegid());
 204     init = true;
 205   }
 206   return privileges;
 207 }
 208 
 209 
 210 
 211 // Cpu architecture string
 212 #if   defined(ZERO)
 213 static char cpu_arch[] = ZERO_LIBARCH;
 214 #elif defined(IA64)
 215 static char cpu_arch[] = "ia64";
 216 #elif defined(IA32)
 217 static char cpu_arch[] = "i386";
 218 #elif defined(AMD64)
 219 static char cpu_arch[] = "amd64";
 220 #elif defined(ARM)
 221 static char cpu_arch[] = "arm";
 222 #elif defined(PPC)
 223 static char cpu_arch[] = "ppc";
 224 #elif defined(SPARC)
 225 #  ifdef _LP64
 226 static char cpu_arch[] = "sparcv9";
 227 #  else
 228 static char cpu_arch[] = "sparc";
 229 #  endif
 230 #else
 231 #error Add appropriate cpu_arch setting
 232 #endif
 233 
 234 // Compiler variant
 235 #ifdef COMPILER2
 236 #define COMPILER_VARIANT "server"
 237 #else
 238 #define COMPILER_VARIANT "client"
 239 #endif
 240 
 241 
 242 void os::Bsd::initialize_system_info() {
 243   int mib[2];
 244   size_t len;
 245   int cpu_val;
 246   julong mem_val;
 247 
 248   /* get processors count via hw.ncpus sysctl */
 249   mib[0] = CTL_HW;
 250   mib[1] = HW_NCPU;
 251   len = sizeof(cpu_val);
 252   if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
 253        assert(len == sizeof(cpu_val), "unexpected data size");
 254        set_processor_count(cpu_val);
 255   }
 256   else {
 257        set_processor_count(1);   // fallback
 258   }
 259 
 260   /* get physical memory via hw.memsize sysctl (hw.memsize is used
 261    * since it returns a 64 bit value)
 262    */
 263   mib[0] = CTL_HW;
 264   mib[1] = HW_MEMSIZE;
 265   len = sizeof(mem_val);
 266   if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
 267        assert(len == sizeof(mem_val), "unexpected data size");
 268        _physical_memory = mem_val;
 269   } else {
 270        _physical_memory = 256*1024*1024;       // fallback (XXXBSD?)
 271   }
 272 
 273 #ifdef __OpenBSD__
 274   {
 275        // limit _physical_memory memory view on OpenBSD since
 276        // datasize rlimit restricts us anyway.
 277        struct rlimit limits;
 278        getrlimit(RLIMIT_DATA, &limits);
 279        _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
 280   }
 281 #endif
 282 }
 283 
 284 #ifdef __APPLE__
 285 static const char *get_home() {
 286   const char *home_dir = ::getenv("HOME");
 287   if ((home_dir == NULL) || (*home_dir == '\0')) {
 288     struct passwd *passwd_info = getpwuid(geteuid());
 289     if (passwd_info != NULL) {
 290       home_dir = passwd_info->pw_dir;
 291     }
 292   }
 293 
 294   return home_dir;
 295 }
 296 #endif
 297 
 298 void os::init_system_properties_values() {
 299 //  char arch[12];
 300 //  sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
 301 
 302   // The next steps are taken in the product version:
 303   //
 304   // Obtain the JAVA_HOME value from the location of libjvm.so.
 305   // This library should be located at:
 306   // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
 307   //
 308   // If "/jre/lib/" appears at the right place in the path, then we
 309   // assume libjvm.so is installed in a JDK and we use this path.
 310   //
 311   // Otherwise exit with message: "Could not create the Java virtual machine."
 312   //
 313   // The following extra steps are taken in the debugging version:
 314   //
 315   // If "/jre/lib/" does NOT appear at the right place in the path
 316   // instead of exit check for $JAVA_HOME environment variable.
 317   //
 318   // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
 319   // then we append a fake suffix "hotspot/libjvm.so" to this path so
 320   // it looks like libjvm.so is installed there
 321   // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
 322   //
 323   // Otherwise exit.
 324   //
 325   // Important note: if the location of libjvm.so changes this
 326   // code needs to be changed accordingly.
 327 
 328   // The next few definitions allow the code to be verbatim:
 329 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
 330 #define getenv(n) ::getenv(n)
 331 
 332 /*
 333  * See ld(1):
 334  *      The linker uses the following search paths to locate required
 335  *      shared libraries:
 336  *        1: ...
 337  *        ...
 338  *        7: The default directories, normally /lib and /usr/lib.
 339  */
 340 #ifndef DEFAULT_LIBPATH
 341 #define DEFAULT_LIBPATH "/lib:/usr/lib"
 342 #endif
 343 
 344 #define EXTENSIONS_DIR  "/lib/ext"
 345 #define ENDORSED_DIR    "/lib/endorsed"
 346 #define REG_DIR         "/usr/java/packages"
 347 
 348 #ifdef __APPLE__
 349 #define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
 350 #define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
 351         const char *user_home_dir = get_home();
 352         // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
 353         int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
 354             sizeof(SYS_EXTENSIONS_DIRS);
 355 #endif
 356 
 357   {
 358     /* sysclasspath, java_home, dll_dir */
 359     {
 360         char *home_path;
 361         char *dll_path;
 362         char *pslash;
 363         char buf[MAXPATHLEN];
 364         os::jvm_path(buf, sizeof(buf));
 365 
 366         // Found the full path to libjvm.so.
 367         // Now cut the path to <java_home>/jre if we can.
 368         *(strrchr(buf, '/')) = '\0';  /* get rid of /libjvm.so */
 369         pslash = strrchr(buf, '/');
 370         if (pslash != NULL)
 371             *pslash = '\0';           /* get rid of /{client|server|hotspot} */
 372         dll_path = malloc(strlen(buf) + 1);
 373         if (dll_path == NULL)
 374             return;
 375         strcpy(dll_path, buf);
 376         Arguments::set_dll_dir(dll_path);
 377 
 378         if (pslash != NULL) {
 379             pslash = strrchr(buf, '/');
 380             if (pslash != NULL) {
 381                 *pslash = '\0';       /* get rid of /<arch> (/lib on macosx) */
 382 #ifndef __APPLE__
 383                 pslash = strrchr(buf, '/');
 384                 if (pslash != NULL)
 385                     *pslash = '\0';   /* get rid of /lib */
 386 #endif
 387             }
 388         }
 389 
 390         home_path = malloc(strlen(buf) + 1);
 391         if (home_path == NULL)
 392             return;
 393         strcpy(home_path, buf);
 394         Arguments::set_java_home(home_path);
 395 
 396         if (!set_boot_path('/', ':'))
 397             return;
 398     }
 399 
 400     /*
 401      * Where to look for native libraries
 402      *
 403      * Note: Due to a legacy implementation, most of the library path
 404      * is set in the launcher.  This was to accomodate linking restrictions
 405      * on legacy Bsd implementations (which are no longer supported).
 406      * Eventually, all the library path setting will be done here.
 407      *
 408      * However, to prevent the proliferation of improperly built native
 409      * libraries, the new path component /usr/java/packages is added here.
 410      * Eventually, all the library path setting will be done here.
 411      */
 412     {
 413         char *ld_library_path;
 414 
 415         /*
 416          * Construct the invariant part of ld_library_path. Note that the
 417          * space for the colon and the trailing null are provided by the
 418          * nulls included by the sizeof operator (so actually we allocate
 419          * a byte more than necessary).
 420          */
 421 #ifdef __APPLE__
 422         ld_library_path = (char *) malloc(system_ext_size);
 423         sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
 424 #else
 425         ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
 426             strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
 427         sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
 428 #endif
 429 
 430         /*
 431          * Get the user setting of LD_LIBRARY_PATH, and prepended it.  It
 432          * should always exist (until the legacy problem cited above is
 433          * addressed).
 434          */
 435 #ifdef __APPLE__
 436         // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
 437         char *l = getenv("JAVA_LIBRARY_PATH");
 438         if (l != NULL) {
 439             char *t = ld_library_path;
 440             /* That's +1 for the colon and +1 for the trailing '\0' */
 441             ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
 442             sprintf(ld_library_path, "%s:%s", l, t);
 443             free(t);
 444         }
 445 
 446         char *v = getenv("DYLD_LIBRARY_PATH");
 447 #else
 448         char *v = getenv("LD_LIBRARY_PATH");
 449 #endif
 450         if (v != NULL) {
 451             char *t = ld_library_path;
 452             /* That's +1 for the colon and +1 for the trailing '\0' */
 453             ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
 454             sprintf(ld_library_path, "%s:%s", v, t);
 455             free(t);
 456         }
 457 
 458 #ifdef __APPLE__
 459         // Apple's Java6 has "." at the beginning of java.library.path.
 460         // OpenJDK on Windows has "." at the end of java.library.path.
 461         // OpenJDK on Linux and Solaris don't have "." in java.library.path
 462         // at all. To ease the transition from Apple's Java6 to OpenJDK7,
 463         // "." is appended to the end of java.library.path. Yes, this
 464         // could cause a change in behavior, but Apple's Java6 behavior
 465         // can be achieved by putting "." at the beginning of the
 466         // JAVA_LIBRARY_PATH environment variable.
 467         {
 468             char *t = ld_library_path;
 469             // that's +3 for appending ":." and the trailing '\0'
 470             ld_library_path = (char *) malloc(strlen(t) + 3);
 471             sprintf(ld_library_path, "%s:%s", t, ".");
 472             free(t);
 473         }
 474 #endif
 475 
 476         Arguments::set_library_path(ld_library_path);
 477     }
 478 
 479     /*
 480      * Extensions directories.
 481      *
 482      * Note that the space for the colon and the trailing null are provided
 483      * by the nulls included by the sizeof operator (so actually one byte more
 484      * than necessary is allocated).
 485      */
 486     {
 487 #ifdef __APPLE__
 488         char *buf = malloc(strlen(Arguments::get_java_home()) +
 489             sizeof(EXTENSIONS_DIR) + system_ext_size);
 490         sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
 491             SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
 492 #else
 493         char *buf = malloc(strlen(Arguments::get_java_home()) +
 494             sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
 495         sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
 496             Arguments::get_java_home());
 497 #endif
 498 
 499         Arguments::set_ext_dirs(buf);
 500     }
 501 
 502     /* Endorsed standards default directory. */
 503     {
 504         char * buf;
 505         buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
 506         sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
 507         Arguments::set_endorsed_dirs(buf);
 508     }
 509   }
 510 
 511 #ifdef __APPLE__
 512 #undef SYS_EXTENSIONS_DIR
 513 #endif
 514 #undef malloc
 515 #undef getenv
 516 #undef EXTENSIONS_DIR
 517 #undef ENDORSED_DIR
 518 
 519   // Done
 520   return;
 521 }
 522 
 523 ////////////////////////////////////////////////////////////////////////////////
 524 // breakpoint support
 525 
 526 void os::breakpoint() {
 527   BREAKPOINT;
 528 }
 529 
 530 extern "C" void breakpoint() {
 531   // use debugger to set breakpoint here
 532 }
 533 
 534 ////////////////////////////////////////////////////////////////////////////////
 535 // signal support
 536 
 537 debug_only(static bool signal_sets_initialized = false);
 538 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
 539 
 540 bool os::Bsd::is_sig_ignored(int sig) {
 541       struct sigaction oact;
 542       sigaction(sig, (struct sigaction*)NULL, &oact);
 543       void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
 544                                      : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
 545       if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
 546            return true;
 547       else
 548            return false;
 549 }
 550 
 551 void os::Bsd::signal_sets_init() {
 552   // Should also have an assertion stating we are still single-threaded.
 553   assert(!signal_sets_initialized, "Already initialized");
 554   // Fill in signals that are necessarily unblocked for all threads in
 555   // the VM. Currently, we unblock the following signals:
 556   // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
 557   //                         by -Xrs (=ReduceSignalUsage));
 558   // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
 559   // other threads. The "ReduceSignalUsage" boolean tells us not to alter
 560   // the dispositions or masks wrt these signals.
 561   // Programs embedding the VM that want to use the above signals for their
 562   // own purposes must, at this time, use the "-Xrs" option to prevent
 563   // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
 564   // (See bug 4345157, and other related bugs).
 565   // In reality, though, unblocking these signals is really a nop, since
 566   // these signals are not blocked by default.
 567   sigemptyset(&unblocked_sigs);
 568   sigemptyset(&allowdebug_blocked_sigs);
 569   sigaddset(&unblocked_sigs, SIGILL);
 570   sigaddset(&unblocked_sigs, SIGSEGV);
 571   sigaddset(&unblocked_sigs, SIGBUS);
 572   sigaddset(&unblocked_sigs, SIGFPE);
 573   sigaddset(&unblocked_sigs, SR_signum);
 574 
 575   if (!ReduceSignalUsage) {
 576    if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
 577       sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
 578       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
 579    }
 580    if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
 581       sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
 582       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
 583    }
 584    if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
 585       sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
 586       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
 587    }
 588   }
 589   // Fill in signals that are blocked by all but the VM thread.
 590   sigemptyset(&vm_sigs);
 591   if (!ReduceSignalUsage)
 592     sigaddset(&vm_sigs, BREAK_SIGNAL);
 593   debug_only(signal_sets_initialized = true);
 594 
 595 }
 596 
 597 // These are signals that are unblocked while a thread is running Java.
 598 // (For some reason, they get blocked by default.)
 599 sigset_t* os::Bsd::unblocked_signals() {
 600   assert(signal_sets_initialized, "Not initialized");
 601   return &unblocked_sigs;
 602 }
 603 
 604 // These are the signals that are blocked while a (non-VM) thread is
 605 // running Java. Only the VM thread handles these signals.
 606 sigset_t* os::Bsd::vm_signals() {
 607   assert(signal_sets_initialized, "Not initialized");
 608   return &vm_sigs;
 609 }
 610 
 611 // These are signals that are blocked during cond_wait to allow debugger in
 612 sigset_t* os::Bsd::allowdebug_blocked_signals() {
 613   assert(signal_sets_initialized, "Not initialized");
 614   return &allowdebug_blocked_sigs;
 615 }
 616 
 617 void os::Bsd::hotspot_sigmask(Thread* thread) {
 618 
 619   //Save caller's signal mask before setting VM signal mask
 620   sigset_t caller_sigmask;
 621   pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
 622 
 623   OSThread* osthread = thread->osthread();
 624   osthread->set_caller_sigmask(caller_sigmask);
 625 
 626   pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
 627 
 628   if (!ReduceSignalUsage) {
 629     if (thread->is_VM_thread()) {
 630       // Only the VM thread handles BREAK_SIGNAL ...
 631       pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
 632     } else {
 633       // ... all other threads block BREAK_SIGNAL
 634       pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
 635     }
 636   }
 637 }
 638 
 639 
 640 //////////////////////////////////////////////////////////////////////////////
 641 // create new thread
 642 
 643 static address highest_vm_reserved_address();
 644 
 645 // check if it's safe to start a new thread
 646 static bool _thread_safety_check(Thread* thread) {
 647   return true;
 648 }
 649 
 650 #ifdef __APPLE__
 651 // library handle for calling objc_registerThreadWithCollector()
 652 // without static linking to the libobjc library
 653 #define OBJC_LIB "/usr/lib/libobjc.dylib"
 654 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
 655 typedef void (*objc_registerThreadWithCollector_t)();
 656 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
 657 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
 658 #endif
 659 
 660 #ifdef __APPLE__
 661 static uint64_t locate_unique_thread_id() {
 662   // Additional thread_id used to correlate threads in SA
 663   thread_identifier_info_data_t     m_ident_info;
 664   mach_msg_type_number_t            count = THREAD_IDENTIFIER_INFO_COUNT;
 665 
 666   thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
 667               (thread_info_t) &m_ident_info, &count);
 668   return m_ident_info.thread_id;
 669 }
 670 #endif
 671 
 672 // Thread start routine for all newly created threads
 673 static void *java_start(Thread *thread) {
 674   // Try to randomize the cache line index of hot stack frames.
 675   // This helps when threads of the same stack traces evict each other's
 676   // cache lines. The threads can be either from the same JVM instance, or
 677   // from different JVM instances. The benefit is especially true for
 678   // processors with hyperthreading technology.
 679   static int counter = 0;
 680   int pid = os::current_process_id();
 681   alloca(((pid ^ counter++) & 7) * 128);
 682 
 683   ThreadLocalStorage::set_thread(thread);
 684 
 685   OSThread* osthread = thread->osthread();
 686   Monitor* sync = osthread->startThread_lock();
 687 
 688   // non floating stack BsdThreads needs extra check, see above
 689   if (!_thread_safety_check(thread)) {
 690     // notify parent thread
 691     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
 692     osthread->set_state(ZOMBIE);
 693     sync->notify_all();
 694     return NULL;
 695   }
 696 
 697 #ifdef __APPLE__
 698   // thread_id is mach thread on macos
 699   osthread->set_thread_id(::mach_thread_self());
 700   osthread->set_unique_thread_id(locate_unique_thread_id());
 701 #else
 702   // thread_id is pthread_id on BSD
 703   osthread->set_thread_id(::pthread_self());
 704 #endif
 705   // initialize signal mask for this thread
 706   os::Bsd::hotspot_sigmask(thread);
 707 
 708   // initialize floating point control register
 709   os::Bsd::init_thread_fpu_state();
 710 
 711 #ifdef __APPLE__
 712   // register thread with objc gc
 713   if (objc_registerThreadWithCollectorFunction != NULL) {
 714     objc_registerThreadWithCollectorFunction();
 715   }
 716 #endif
 717 
 718   // handshaking with parent thread
 719   {
 720     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
 721 
 722     // notify parent thread
 723     osthread->set_state(INITIALIZED);
 724     sync->notify_all();
 725 
 726     // wait until os::start_thread()
 727     while (osthread->get_state() == INITIALIZED) {
 728       sync->wait(Mutex::_no_safepoint_check_flag);
 729     }
 730   }
 731 
 732   // call one more level start routine
 733   thread->run();
 734 
 735   return 0;
 736 }
 737 
 738 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
 739   assert(thread->osthread() == NULL, "caller responsible");
 740 
 741   // Allocate the OSThread object
 742   OSThread* osthread = new OSThread(NULL, NULL);
 743   if (osthread == NULL) {
 744     return false;
 745   }
 746 
 747   // set the correct thread state
 748   osthread->set_thread_type(thr_type);
 749 
 750   // Initial state is ALLOCATED but not INITIALIZED
 751   osthread->set_state(ALLOCATED);
 752 
 753   thread->set_osthread(osthread);
 754 
 755   // init thread attributes
 756   pthread_attr_t attr;
 757   pthread_attr_init(&attr);
 758   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 759 
 760   // stack size
 761   if (os::Bsd::supports_variable_stack_size()) {
 762     // calculate stack size if it's not specified by caller
 763     if (stack_size == 0) {
 764       stack_size = os::Bsd::default_stack_size(thr_type);
 765 
 766       switch (thr_type) {
 767       case os::java_thread:
 768         // Java threads use ThreadStackSize which default value can be
 769         // changed with the flag -Xss
 770         assert (JavaThread::stack_size_at_create() > 0, "this should be set");
 771         stack_size = JavaThread::stack_size_at_create();
 772         break;
 773       case os::compiler_thread:
 774         if (CompilerThreadStackSize > 0) {
 775           stack_size = (size_t)(CompilerThreadStackSize * K);
 776           break;
 777         } // else fall through:
 778           // use VMThreadStackSize if CompilerThreadStackSize is not defined
 779       case os::vm_thread:
 780       case os::pgc_thread:
 781       case os::cgc_thread:
 782       case os::watcher_thread:
 783         if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
 784         break;
 785       }
 786     }
 787 
 788     stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
 789     pthread_attr_setstacksize(&attr, stack_size);
 790   } else {
 791     // let pthread_create() pick the default value.
 792   }
 793 
 794   ThreadState state;
 795 
 796   {
 797     pthread_t tid;
 798     int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
 799 
 800     pthread_attr_destroy(&attr);
 801 
 802     if (ret != 0) {
 803       if (PrintMiscellaneous && (Verbose || WizardMode)) {
 804         perror("pthread_create()");
 805       }
 806       // Need to clean up stuff we've allocated so far
 807       thread->set_osthread(NULL);
 808       delete osthread;
 809       return false;
 810     }
 811 
 812     // Store pthread info into the OSThread
 813     osthread->set_pthread_id(tid);
 814 
 815     // Wait until child thread is either initialized or aborted
 816     {
 817       Monitor* sync_with_child = osthread->startThread_lock();
 818       MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
 819       while ((state = osthread->get_state()) == ALLOCATED) {
 820         sync_with_child->wait(Mutex::_no_safepoint_check_flag);
 821       }
 822     }
 823 
 824   }
 825 
 826   // Aborted due to thread limit being reached
 827   if (state == ZOMBIE) {
 828       thread->set_osthread(NULL);
 829       delete osthread;
 830       return false;
 831   }
 832 
 833   // The thread is returned suspended (in state INITIALIZED),
 834   // and is started higher up in the call chain
 835   assert(state == INITIALIZED, "race condition");
 836   return true;
 837 }
 838 
 839 /////////////////////////////////////////////////////////////////////////////
 840 // attach existing thread
 841 
 842 // bootstrap the main thread
 843 bool os::create_main_thread(JavaThread* thread) {
 844   assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
 845   return create_attached_thread(thread);
 846 }
 847 
 848 bool os::create_attached_thread(JavaThread* thread) {
 849 #ifdef ASSERT
 850     thread->verify_not_published();
 851 #endif
 852 
 853   // Allocate the OSThread object
 854   OSThread* osthread = new OSThread(NULL, NULL);
 855 
 856   if (osthread == NULL) {
 857     return false;
 858   }
 859 
 860   // Store pthread info into the OSThread
 861 #ifdef __APPLE__
 862   osthread->set_thread_id(::mach_thread_self());
 863   osthread->set_unique_thread_id(locate_unique_thread_id());
 864 #else
 865   osthread->set_thread_id(::pthread_self());
 866 #endif
 867   osthread->set_pthread_id(::pthread_self());
 868 
 869   // initialize floating point control register
 870   os::Bsd::init_thread_fpu_state();
 871 
 872   // Initial thread state is RUNNABLE
 873   osthread->set_state(RUNNABLE);
 874 
 875   thread->set_osthread(osthread);
 876 
 877   // initialize signal mask for this thread
 878   // and save the caller's signal mask
 879   os::Bsd::hotspot_sigmask(thread);
 880 
 881   return true;
 882 }
 883 
 884 void os::pd_start_thread(Thread* thread) {
 885   OSThread * osthread = thread->osthread();
 886   assert(osthread->get_state() != INITIALIZED, "just checking");
 887   Monitor* sync_with_child = osthread->startThread_lock();
 888   MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
 889   sync_with_child->notify();
 890 }
 891 
 892 // Free Bsd resources related to the OSThread
 893 void os::free_thread(OSThread* osthread) {
 894   assert(osthread != NULL, "osthread not set");
 895 
 896   if (Thread::current()->osthread() == osthread) {
 897     // Restore caller's signal mask
 898     sigset_t sigmask = osthread->caller_sigmask();
 899     pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
 900    }
 901 
 902   delete osthread;
 903 }
 904 
 905 //////////////////////////////////////////////////////////////////////////////
 906 // thread local storage
 907 
 908 int os::allocate_thread_local_storage() {
 909   pthread_key_t key;
 910   int rslt = pthread_key_create(&key, NULL);
 911   assert(rslt == 0, "cannot allocate thread local storage");
 912   return (int)key;
 913 }
 914 
 915 // Note: This is currently not used by VM, as we don't destroy TLS key
 916 // on VM exit.
 917 void os::free_thread_local_storage(int index) {
 918   int rslt = pthread_key_delete((pthread_key_t)index);
 919   assert(rslt == 0, "invalid index");
 920 }
 921 
 922 void os::thread_local_storage_at_put(int index, void* value) {
 923   int rslt = pthread_setspecific((pthread_key_t)index, value);
 924   assert(rslt == 0, "pthread_setspecific failed");
 925 }
 926 
 927 extern "C" Thread* get_thread() {
 928   return ThreadLocalStorage::thread();
 929 }
 930 
 931 
 932 ////////////////////////////////////////////////////////////////////////////////
 933 // time support
 934 
 935 // Time since start-up in seconds to a fine granularity.
 936 // Used by VMSelfDestructTimer and the MemProfiler.
 937 double os::elapsedTime() {
 938 
 939   return (double)(os::elapsed_counter()) * 0.000001;
 940 }
 941 
 942 jlong os::elapsed_counter() {
 943   timeval time;
 944   int status = gettimeofday(&time, NULL);
 945   return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
 946 }
 947 
 948 jlong os::elapsed_frequency() {
 949   return (1000 * 1000);
 950 }
 951 
 952 // XXX: For now, code this as if BSD does not support vtime.
 953 bool os::supports_vtime() { return false; }
 954 bool os::enable_vtime()   { return false; }
 955 bool os::vtime_enabled()  { return false; }
 956 double os::elapsedVTime() {
 957   // better than nothing, but not much
 958   return elapsedTime();
 959 }
 960 
 961 jlong os::javaTimeMillis() {
 962   timeval time;
 963   int status = gettimeofday(&time, NULL);
 964   assert(status != -1, "bsd error");
 965   return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
 966 }
 967 
 968 #ifndef CLOCK_MONOTONIC
 969 #define CLOCK_MONOTONIC (1)
 970 #endif
 971 
 972 #ifdef __APPLE__
 973 void os::Bsd::clock_init() {
 974         // XXXDARWIN: Investigate replacement monotonic clock
 975 }
 976 #else
 977 void os::Bsd::clock_init() {
 978   struct timespec res;
 979   struct timespec tp;
 980   if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
 981       ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
 982     // yes, monotonic clock is supported
 983     _clock_gettime = ::clock_gettime;
 984   }
 985 }
 986 #endif
 987 
 988 
 989 jlong os::javaTimeNanos() {
 990   if (Bsd::supports_monotonic_clock()) {
 991     struct timespec tp;
 992     int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
 993     assert(status == 0, "gettime error");
 994     jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
 995     return result;
 996   } else {
 997     timeval time;
 998     int status = gettimeofday(&time, NULL);
 999     assert(status != -1, "bsd error");
1000     jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1001     return 1000 * usecs;
1002   }
1003 }
1004 
1005 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1006   if (Bsd::supports_monotonic_clock()) {
1007     info_ptr->max_value = ALL_64_BITS;
1008 
1009     // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1010     info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
1011     info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
1012   } else {
1013     // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1014     info_ptr->max_value = ALL_64_BITS;
1015 
1016     // gettimeofday is a real time clock so it skips
1017     info_ptr->may_skip_backward = true;
1018     info_ptr->may_skip_forward = true;
1019   }
1020 
1021   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
1022 }
1023 
1024 // Return the real, user, and system times in seconds from an
1025 // arbitrary fixed point in the past.
1026 bool os::getTimesSecs(double* process_real_time,
1027                       double* process_user_time,
1028                       double* process_system_time) {
1029   struct tms ticks;
1030   clock_t real_ticks = times(&ticks);
1031 
1032   if (real_ticks == (clock_t) (-1)) {
1033     return false;
1034   } else {
1035     double ticks_per_second = (double) clock_tics_per_sec;
1036     *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1037     *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1038     *process_real_time = ((double) real_ticks) / ticks_per_second;
1039 
1040     return true;
1041   }
1042 }
1043 
1044 
1045 char * os::local_time_string(char *buf, size_t buflen) {
1046   struct tm t;
1047   time_t long_time;
1048   time(&long_time);
1049   localtime_r(&long_time, &t);
1050   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1051                t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1052                t.tm_hour, t.tm_min, t.tm_sec);
1053   return buf;
1054 }
1055 
1056 struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
1057   return localtime_r(clock, res);
1058 }
1059 
1060 ////////////////////////////////////////////////////////////////////////////////
1061 // runtime exit support
1062 
1063 // Note: os::shutdown() might be called very early during initialization, or
1064 // called from signal handler. Before adding something to os::shutdown(), make
1065 // sure it is async-safe and can handle partially initialized VM.
1066 void os::shutdown() {
1067 
1068   // allow PerfMemory to attempt cleanup of any persistent resources
1069   perfMemory_exit();
1070 
1071   // needs to remove object in file system
1072   AttachListener::abort();
1073 
1074   // flush buffered output, finish log files
1075   ostream_abort();
1076 
1077   // Check for abort hook
1078   abort_hook_t abort_hook = Arguments::abort_hook();
1079   if (abort_hook != NULL) {
1080     abort_hook();
1081   }
1082 
1083 }
1084 
1085 // Note: os::abort() might be called very early during initialization, or
1086 // called from signal handler. Before adding something to os::abort(), make
1087 // sure it is async-safe and can handle partially initialized VM.
1088 void os::abort(bool dump_core) {
1089   os::shutdown();
1090   if (dump_core) {
1091 #ifndef PRODUCT
1092     fdStream out(defaultStream::output_fd());
1093     out.print_raw("Current thread is ");
1094     char buf[16];
1095     jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1096     out.print_raw_cr(buf);
1097     out.print_raw_cr("Dumping core ...");
1098 #endif
1099     ::abort(); // dump core
1100   }
1101 
1102   ::exit(1);
1103 }
1104 
1105 // Die immediately, no exit hook, no abort hook, no cleanup.
1106 void os::die() {
1107   // _exit() on BsdThreads only kills current thread
1108   ::abort();
1109 }
1110 
1111 // unused on bsd for now.
1112 void os::set_error_file(const char *logfile) {}
1113 
1114 
1115 // This method is a copy of JDK's sysGetLastErrorString
1116 // from src/solaris/hpi/src/system_md.c
1117 
1118 size_t os::lasterror(char *buf, size_t len) {
1119 
1120   if (errno == 0)  return 0;
1121 
1122   const char *s = ::strerror(errno);
1123   size_t n = ::strlen(s);
1124   if (n >= len) {
1125     n = len - 1;
1126   }
1127   ::strncpy(buf, s, n);
1128   buf[n] = '\0';
1129   return n;
1130 }
1131 
1132 intx os::current_thread_id() {
1133 #ifdef __APPLE__
1134   return (intx)::mach_thread_self();
1135 #else
1136   return (intx)::pthread_self();
1137 #endif
1138 }
1139 int os::current_process_id() {
1140 
1141   // Under the old bsd thread library, bsd gives each thread
1142   // its own process id. Because of this each thread will return
1143   // a different pid if this method were to return the result
1144   // of getpid(2). Bsd provides no api that returns the pid
1145   // of the launcher thread for the vm. This implementation
1146   // returns a unique pid, the pid of the launcher thread
1147   // that starts the vm 'process'.
1148 
1149   // Under the NPTL, getpid() returns the same pid as the
1150   // launcher thread rather than a unique pid per thread.
1151   // Use gettid() if you want the old pre NPTL behaviour.
1152 
1153   // if you are looking for the result of a call to getpid() that
1154   // returns a unique pid for the calling thread, then look at the
1155   // OSThread::thread_id() method in osThread_bsd.hpp file
1156 
1157   return (int)(_initial_pid ? _initial_pid : getpid());
1158 }
1159 
1160 // DLL functions
1161 
1162 #define JNI_LIB_PREFIX "lib"
1163 #ifdef __APPLE__
1164 #define JNI_LIB_SUFFIX ".dylib"
1165 #else
1166 #define JNI_LIB_SUFFIX ".so"
1167 #endif
1168 
1169 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1170 
1171 // This must be hard coded because it's the system's temporary
1172 // directory not the java application's temp directory, ala java.io.tmpdir.
1173 #ifdef __APPLE__
1174 // macosx has a secure per-user temporary directory
1175 char temp_path_storage[PATH_MAX];
1176 const char* os::get_temp_directory() {
1177   static char *temp_path = NULL;
1178   if (temp_path == NULL) {
1179     int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1180     if (pathSize == 0 || pathSize > PATH_MAX) {
1181       strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1182     }
1183     temp_path = temp_path_storage;
1184   }
1185   return temp_path;
1186 }
1187 #else /* __APPLE__ */
1188 const char* os::get_temp_directory() { return "/tmp"; }
1189 #endif /* __APPLE__ */
1190 
1191 static bool file_exists(const char* filename) {
1192   struct stat statbuf;
1193   if (filename == NULL || strlen(filename) == 0) {
1194     return false;
1195   }
1196   return os::stat(filename, &statbuf) == 0;
1197 }
1198 
1199 bool os::dll_build_name(char* buffer, size_t buflen,
1200                         const char* pname, const char* fname) {
1201   bool retval = false;
1202   // Copied from libhpi
1203   const size_t pnamelen = pname ? strlen(pname) : 0;
1204 
1205   // Return error on buffer overflow.
1206   if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1207     return retval;
1208   }
1209 
1210   if (pnamelen == 0) {
1211     snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1212     retval = true;
1213   } else if (strchr(pname, *os::path_separator()) != NULL) {
1214     int n;
1215     char** pelements = split_path(pname, &n);
1216     for (int i = 0 ; i < n ; i++) {
1217       // Really shouldn't be NULL, but check can't hurt
1218       if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1219         continue; // skip the empty path values
1220       }
1221       snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1222           pelements[i], fname);
1223       if (file_exists(buffer)) {
1224         retval = true;
1225         break;
1226       }
1227     }
1228     // release the storage
1229     for (int i = 0 ; i < n ; i++) {
1230       if (pelements[i] != NULL) {
1231         FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1232       }
1233     }
1234     if (pelements != NULL) {
1235       FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1236     }
1237   } else {
1238     snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1239     retval = true;
1240   }
1241   return retval;
1242 }
1243 
1244 const char* os::get_current_directory(char *buf, int buflen) {
1245   return getcwd(buf, buflen);
1246 }
1247 
1248 // check if addr is inside libjvm.so
1249 bool os::address_is_in_vm(address addr) {
1250   static address libjvm_base_addr;
1251   Dl_info dlinfo;
1252 
1253   if (libjvm_base_addr == NULL) {
1254     dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1255     libjvm_base_addr = (address)dlinfo.dli_fbase;
1256     assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1257   }
1258 
1259   if (dladdr((void *)addr, &dlinfo)) {
1260     if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1261   }
1262 
1263   return false;
1264 }
1265 
1266 
1267 #define MACH_MAXSYMLEN 256
1268 
1269 bool os::dll_address_to_function_name(address addr, char *buf,
1270                                       int buflen, int *offset) {
1271   Dl_info dlinfo;
1272   char localbuf[MACH_MAXSYMLEN];
1273 
1274   // dladdr will find names of dynamic functions only, but does
1275   // it set dli_fbase with mach_header address when it "fails" ?
1276   if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1277     if (buf != NULL) {
1278       if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1279         jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1280       }
1281     }
1282     if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1283     return true;
1284   } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1285     if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1286        buf, buflen, offset, dlinfo.dli_fname)) {
1287        return true;
1288     }
1289   }
1290 
1291   // Handle non-dymanic manually:
1292   if (dlinfo.dli_fbase != NULL &&
1293       Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1294     if(!Decoder::demangle(localbuf, buf, buflen)) {
1295       jio_snprintf(buf, buflen, "%s", localbuf);
1296     }
1297     return true;
1298   }
1299   if (buf != NULL) buf[0] = '\0';
1300   if (offset != NULL) *offset = -1;
1301   return false;
1302 }
1303 
1304 // ported from solaris version
1305 bool os::dll_address_to_library_name(address addr, char* buf,
1306                                      int buflen, int* offset) {
1307   Dl_info dlinfo;
1308 
1309   if (dladdr((void*)addr, &dlinfo)){
1310      if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1311      if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1312      return true;
1313   } else {
1314      if (buf) buf[0] = '\0';
1315      if (offset) *offset = -1;
1316      return false;
1317   }
1318 }
1319 
1320 // Loads .dll/.so and
1321 // in case of error it checks if .dll/.so was built for the
1322 // same architecture as Hotspot is running on
1323 
1324 #ifdef __APPLE__
1325 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1326   void * result= ::dlopen(filename, RTLD_LAZY);
1327   if (result != NULL) {
1328     // Successful loading
1329     return result;
1330   }
1331 
1332   // Read system error message into ebuf
1333   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1334   ebuf[ebuflen-1]='\0';
1335 
1336   return NULL;
1337 }
1338 #else
1339 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1340 {
1341   void * result= ::dlopen(filename, RTLD_LAZY);
1342   if (result != NULL) {
1343     // Successful loading
1344     return result;
1345   }
1346 
1347   Elf32_Ehdr elf_head;
1348 
1349   // Read system error message into ebuf
1350   // It may or may not be overwritten below
1351   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1352   ebuf[ebuflen-1]='\0';
1353   int diag_msg_max_length=ebuflen-strlen(ebuf);
1354   char* diag_msg_buf=ebuf+strlen(ebuf);
1355 
1356   if (diag_msg_max_length==0) {
1357     // No more space in ebuf for additional diagnostics message
1358     return NULL;
1359   }
1360 
1361 
1362   int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1363 
1364   if (file_descriptor < 0) {
1365     // Can't open library, report dlerror() message
1366     return NULL;
1367   }
1368 
1369   bool failed_to_read_elf_head=
1370     (sizeof(elf_head)!=
1371         (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1372 
1373   ::close(file_descriptor);
1374   if (failed_to_read_elf_head) {
1375     // file i/o error - report dlerror() msg
1376     return NULL;
1377   }
1378 
1379   typedef struct {
1380     Elf32_Half  code;         // Actual value as defined in elf.h
1381     Elf32_Half  compat_class; // Compatibility of archs at VM's sense
1382     char        elf_class;    // 32 or 64 bit
1383     char        endianess;    // MSB or LSB
1384     char*       name;         // String representation
1385   } arch_t;
1386 
1387   #ifndef EM_486
1388   #define EM_486          6               /* Intel 80486 */
1389   #endif
1390 
1391   #ifndef EM_MIPS_RS3_LE
1392   #define EM_MIPS_RS3_LE  10              /* MIPS */
1393   #endif
1394 
1395   #ifndef EM_PPC64
1396   #define EM_PPC64        21              /* PowerPC64 */
1397   #endif
1398 
1399   #ifndef EM_S390
1400   #define EM_S390         22              /* IBM System/390 */
1401   #endif
1402 
1403   #ifndef EM_IA_64
1404   #define EM_IA_64        50              /* HP/Intel IA-64 */
1405   #endif
1406 
1407   #ifndef EM_X86_64
1408   #define EM_X86_64       62              /* AMD x86-64 */
1409   #endif
1410 
1411   static const arch_t arch_array[]={
1412     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1413     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1414     {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1415     {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1416     {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1417     {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1418     {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1419     {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1420     {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1421     {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
1422     {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1423     {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1424     {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1425     {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1426     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1427     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1428   };
1429 
1430   #if  (defined IA32)
1431     static  Elf32_Half running_arch_code=EM_386;
1432   #elif   (defined AMD64)
1433     static  Elf32_Half running_arch_code=EM_X86_64;
1434   #elif  (defined IA64)
1435     static  Elf32_Half running_arch_code=EM_IA_64;
1436   #elif  (defined __sparc) && (defined _LP64)
1437     static  Elf32_Half running_arch_code=EM_SPARCV9;
1438   #elif  (defined __sparc) && (!defined _LP64)
1439     static  Elf32_Half running_arch_code=EM_SPARC;
1440   #elif  (defined __powerpc64__)
1441     static  Elf32_Half running_arch_code=EM_PPC64;
1442   #elif  (defined __powerpc__)
1443     static  Elf32_Half running_arch_code=EM_PPC;
1444   #elif  (defined ARM)
1445     static  Elf32_Half running_arch_code=EM_ARM;
1446   #elif  (defined S390)
1447     static  Elf32_Half running_arch_code=EM_S390;
1448   #elif  (defined ALPHA)
1449     static  Elf32_Half running_arch_code=EM_ALPHA;
1450   #elif  (defined MIPSEL)
1451     static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1452   #elif  (defined PARISC)
1453     static  Elf32_Half running_arch_code=EM_PARISC;
1454   #elif  (defined MIPS)
1455     static  Elf32_Half running_arch_code=EM_MIPS;
1456   #elif  (defined M68K)
1457     static  Elf32_Half running_arch_code=EM_68K;
1458   #else
1459     #error Method os::dll_load requires that one of following is defined:\
1460          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1461   #endif
1462 
1463   // Identify compatability class for VM's architecture and library's architecture
1464   // Obtain string descriptions for architectures
1465 
1466   arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1467   int running_arch_index=-1;
1468 
1469   for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1470     if (running_arch_code == arch_array[i].code) {
1471       running_arch_index    = i;
1472     }
1473     if (lib_arch.code == arch_array[i].code) {
1474       lib_arch.compat_class = arch_array[i].compat_class;
1475       lib_arch.name         = arch_array[i].name;
1476     }
1477   }
1478 
1479   assert(running_arch_index != -1,
1480     "Didn't find running architecture code (running_arch_code) in arch_array");
1481   if (running_arch_index == -1) {
1482     // Even though running architecture detection failed
1483     // we may still continue with reporting dlerror() message
1484     return NULL;
1485   }
1486 
1487   if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1488     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1489     return NULL;
1490   }
1491 
1492 #ifndef S390
1493   if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1494     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1495     return NULL;
1496   }
1497 #endif // !S390
1498 
1499   if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1500     if ( lib_arch.name!=NULL ) {
1501       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1502         " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1503         lib_arch.name, arch_array[running_arch_index].name);
1504     } else {
1505       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1506       " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1507         lib_arch.code,
1508         arch_array[running_arch_index].name);
1509     }
1510   }
1511 
1512   return NULL;
1513 }
1514 #endif /* !__APPLE__ */
1515 
1516 // XXX: Do we need a lock around this as per Linux?
1517 void* os::dll_lookup(void* handle, const char* name) {
1518   return dlsym(handle, name);
1519 }
1520 
1521 
1522 static bool _print_ascii_file(const char* filename, outputStream* st) {
1523   int fd = ::open(filename, O_RDONLY);
1524   if (fd == -1) {
1525      return false;
1526   }
1527 
1528   char buf[32];
1529   int bytes;
1530   while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1531     st->print_raw(buf, bytes);
1532   }
1533 
1534   ::close(fd);
1535 
1536   return true;
1537 }
1538 
1539 void os::print_dll_info(outputStream *st) {
1540    st->print_cr("Dynamic libraries:");
1541 #ifdef RTLD_DI_LINKMAP
1542     Dl_info dli;
1543     void *handle;
1544     Link_map *map;
1545     Link_map *p;
1546 
1547     if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
1548         st->print_cr("Error: Cannot print dynamic libraries.");
1549         return;
1550     }
1551     handle = dlopen(dli.dli_fname, RTLD_LAZY);
1552     if (handle == NULL) {
1553         st->print_cr("Error: Cannot print dynamic libraries.");
1554         return;
1555     }
1556     dlinfo(handle, RTLD_DI_LINKMAP, &map);
1557     if (map == NULL) {
1558         st->print_cr("Error: Cannot print dynamic libraries.");
1559         return;
1560     }
1561 
1562     while (map->l_prev != NULL)
1563         map = map->l_prev;
1564 
1565     while (map != NULL) {
1566         st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1567         map = map->l_next;
1568     }
1569 
1570     dlclose(handle);
1571 #elif defined(__APPLE__)
1572     uint32_t count;
1573     uint32_t i;
1574 
1575     count = _dyld_image_count();
1576     for (i = 1; i < count; i++) {
1577         const char *name = _dyld_get_image_name(i);
1578         intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1579         st->print_cr(PTR_FORMAT " \t%s", slide, name);
1580     }
1581 #else
1582    st->print_cr("Error: Cannot print dynamic libraries.");
1583 #endif
1584 }
1585 
1586 void os::print_os_info_brief(outputStream* st) {
1587   st->print("Bsd");
1588 
1589   os::Posix::print_uname_info(st);
1590 }
1591 
1592 void os::print_os_info(outputStream* st) {
1593   st->print("OS:");
1594   st->print("Bsd");
1595 
1596   os::Posix::print_uname_info(st);
1597 
1598   os::Posix::print_rlimit_info(st);
1599 
1600   os::Posix::print_load_average(st);
1601 }
1602 
1603 void os::pd_print_cpu_info(outputStream* st) {
1604   // Nothing to do for now.
1605 }
1606 
1607 void os::print_memory_info(outputStream* st) {
1608 
1609   st->print("Memory:");
1610   st->print(" %dk page", os::vm_page_size()>>10);
1611 
1612   st->print(", physical " UINT64_FORMAT "k",
1613             os::physical_memory() >> 10);
1614   st->print("(" UINT64_FORMAT "k free)",
1615             os::available_memory() >> 10);
1616   st->cr();
1617 
1618   // meminfo
1619   st->print("\n/proc/meminfo:\n");
1620   _print_ascii_file("/proc/meminfo", st);
1621   st->cr();
1622 }
1623 
1624 // Taken from /usr/include/bits/siginfo.h  Supposed to be architecture specific
1625 // but they're the same for all the bsd arch that we support
1626 // and they're the same for solaris but there's no common place to put this.
1627 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1628                           "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1629                           "ILL_COPROC", "ILL_BADSTK" };
1630 
1631 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1632                           "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1633                           "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1634 
1635 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1636 
1637 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1638 
1639 void os::print_siginfo(outputStream* st, void* siginfo) {
1640   st->print("siginfo:");
1641 
1642   const int buflen = 100;
1643   char buf[buflen];
1644   siginfo_t *si = (siginfo_t*)siginfo;
1645   st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1646   if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1647     st->print("si_errno=%s", buf);
1648   } else {
1649     st->print("si_errno=%d", si->si_errno);
1650   }
1651   const int c = si->si_code;
1652   assert(c > 0, "unexpected si_code");
1653   switch (si->si_signo) {
1654   case SIGILL:
1655     st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1656     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1657     break;
1658   case SIGFPE:
1659     st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1660     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1661     break;
1662   case SIGSEGV:
1663     st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1664     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1665     break;
1666   case SIGBUS:
1667     st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1668     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1669     break;
1670   default:
1671     st->print(", si_code=%d", si->si_code);
1672     // no si_addr
1673   }
1674 
1675   if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1676       UseSharedSpaces) {
1677     FileMapInfo* mapinfo = FileMapInfo::current_info();
1678     if (mapinfo->is_in_shared_space(si->si_addr)) {
1679       st->print("\n\nError accessing class data sharing archive."   \
1680                 " Mapped file inaccessible during execution, "      \
1681                 " possible disk/network problem.");
1682     }
1683   }
1684   st->cr();
1685 }
1686 
1687 
1688 static void print_signal_handler(outputStream* st, int sig,
1689                                  char* buf, size_t buflen);
1690 
1691 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1692   st->print_cr("Signal Handlers:");
1693   print_signal_handler(st, SIGSEGV, buf, buflen);
1694   print_signal_handler(st, SIGBUS , buf, buflen);
1695   print_signal_handler(st, SIGFPE , buf, buflen);
1696   print_signal_handler(st, SIGPIPE, buf, buflen);
1697   print_signal_handler(st, SIGXFSZ, buf, buflen);
1698   print_signal_handler(st, SIGILL , buf, buflen);
1699   print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1700   print_signal_handler(st, SR_signum, buf, buflen);
1701   print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1702   print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1703   print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1704   print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1705 }
1706 
1707 static char saved_jvm_path[MAXPATHLEN] = {0};
1708 
1709 // Find the full path to the current module, libjvm
1710 void os::jvm_path(char *buf, jint buflen) {
1711   // Error checking.
1712   if (buflen < MAXPATHLEN) {
1713     assert(false, "must use a large-enough buffer");
1714     buf[0] = '\0';
1715     return;
1716   }
1717   // Lazy resolve the path to current module.
1718   if (saved_jvm_path[0] != 0) {
1719     strcpy(buf, saved_jvm_path);
1720     return;
1721   }
1722 
1723   char dli_fname[MAXPATHLEN];
1724   bool ret = dll_address_to_library_name(
1725                 CAST_FROM_FN_PTR(address, os::jvm_path),
1726                 dli_fname, sizeof(dli_fname), NULL);
1727   assert(ret != 0, "cannot locate libjvm");
1728   char *rp = realpath(dli_fname, buf);
1729   if (rp == NULL)
1730     return;
1731 
1732   if (Arguments::created_by_gamma_launcher()) {
1733     // Support for the gamma launcher.  Typical value for buf is
1734     // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm".  If "/jre/lib/" appears at
1735     // the right place in the string, then assume we are installed in a JDK and
1736     // we're done.  Otherwise, check for a JAVA_HOME environment variable and
1737     // construct a path to the JVM being overridden.
1738 
1739     const char *p = buf + strlen(buf) - 1;
1740     for (int count = 0; p > buf && count < 5; ++count) {
1741       for (--p; p > buf && *p != '/'; --p)
1742         /* empty */ ;
1743     }
1744 
1745     if (strncmp(p, "/jre/lib/", 9) != 0) {
1746       // Look for JAVA_HOME in the environment.
1747       char* java_home_var = ::getenv("JAVA_HOME");
1748       if (java_home_var != NULL && java_home_var[0] != 0) {
1749         char* jrelib_p;
1750         int len;
1751 
1752         // Check the current module name "libjvm"
1753         p = strrchr(buf, '/');
1754         assert(strstr(p, "/libjvm") == p, "invalid library name");
1755 
1756         rp = realpath(java_home_var, buf);
1757         if (rp == NULL)
1758           return;
1759 
1760         // determine if this is a legacy image or modules image
1761         // modules image doesn't have "jre" subdirectory
1762         len = strlen(buf);
1763         jrelib_p = buf + len;
1764 
1765         // Add the appropriate library subdir
1766         snprintf(jrelib_p, buflen-len, "/jre/lib");
1767         if (0 != access(buf, F_OK)) {
1768           snprintf(jrelib_p, buflen-len, "/lib");
1769         }
1770 
1771         // Add the appropriate client or server subdir
1772         len = strlen(buf);
1773         jrelib_p = buf + len;
1774         snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1775         if (0 != access(buf, F_OK)) {
1776           snprintf(jrelib_p, buflen-len, "");
1777         }
1778 
1779         // If the path exists within JAVA_HOME, add the JVM library name
1780         // to complete the path to JVM being overridden.  Otherwise fallback
1781         // to the path to the current library.
1782         if (0 == access(buf, F_OK)) {
1783           // Use current module name "libjvm"
1784           len = strlen(buf);
1785           snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1786         } else {
1787           // Fall back to path of current library
1788           rp = realpath(dli_fname, buf);
1789           if (rp == NULL)
1790             return;
1791         }
1792       }
1793     }
1794   }
1795 
1796   strcpy(saved_jvm_path, buf);
1797 }
1798 
1799 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1800   // no prefix required, not even "_"
1801 }
1802 
1803 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1804   // no suffix required
1805 }
1806 
1807 ////////////////////////////////////////////////////////////////////////////////
1808 // sun.misc.Signal support
1809 
1810 static volatile jint sigint_count = 0;
1811 
1812 static void
1813 UserHandler(int sig, void *siginfo, void *context) {
1814   // 4511530 - sem_post is serialized and handled by the manager thread. When
1815   // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1816   // don't want to flood the manager thread with sem_post requests.
1817   if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1818       return;
1819 
1820   // Ctrl-C is pressed during error reporting, likely because the error
1821   // handler fails to abort. Let VM die immediately.
1822   if (sig == SIGINT && is_error_reported()) {
1823      os::die();
1824   }
1825 
1826   os::signal_notify(sig);
1827 }
1828 
1829 void* os::user_handler() {
1830   return CAST_FROM_FN_PTR(void*, UserHandler);
1831 }
1832 
1833 extern "C" {
1834   typedef void (*sa_handler_t)(int);
1835   typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1836 }
1837 
1838 void* os::signal(int signal_number, void* handler) {
1839   struct sigaction sigAct, oldSigAct;
1840 
1841   sigfillset(&(sigAct.sa_mask));
1842   sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
1843   sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1844 
1845   if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1846     // -1 means registration failed
1847     return (void *)-1;
1848   }
1849 
1850   return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1851 }
1852 
1853 void os::signal_raise(int signal_number) {
1854   ::raise(signal_number);
1855 }
1856 
1857 /*
1858  * The following code is moved from os.cpp for making this
1859  * code platform specific, which it is by its very nature.
1860  */
1861 
1862 // Will be modified when max signal is changed to be dynamic
1863 int os::sigexitnum_pd() {
1864   return NSIG;
1865 }
1866 
1867 // a counter for each possible signal value
1868 static volatile jint pending_signals[NSIG+1] = { 0 };
1869 
1870 // Bsd(POSIX) specific hand shaking semaphore.
1871 #ifdef __APPLE__
1872 static semaphore_t sig_sem;
1873 #define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1874 #define SEM_WAIT(sem)           semaphore_wait(sem);
1875 #define SEM_POST(sem)           semaphore_signal(sem);
1876 #else
1877 static sem_t sig_sem;
1878 #define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
1879 #define SEM_WAIT(sem)           sem_wait(&sem);
1880 #define SEM_POST(sem)           sem_post(&sem);
1881 #endif
1882 
1883 void os::signal_init_pd() {
1884   // Initialize signal structures
1885   ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1886 
1887   // Initialize signal semaphore
1888   ::SEM_INIT(sig_sem, 0);
1889 }
1890 
1891 void os::signal_notify(int sig) {
1892   Atomic::inc(&pending_signals[sig]);
1893   ::SEM_POST(sig_sem);
1894 }
1895 
1896 static int check_pending_signals(bool wait) {
1897   Atomic::store(0, &sigint_count);
1898   for (;;) {
1899     for (int i = 0; i < NSIG + 1; i++) {
1900       jint n = pending_signals[i];
1901       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1902         return i;
1903       }
1904     }
1905     if (!wait) {
1906       return -1;
1907     }
1908     JavaThread *thread = JavaThread::current();
1909     ThreadBlockInVM tbivm(thread);
1910 
1911     bool threadIsSuspended;
1912     do {
1913       thread->set_suspend_equivalent();
1914       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1915       ::SEM_WAIT(sig_sem);
1916 
1917       // were we externally suspended while we were waiting?
1918       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1919       if (threadIsSuspended) {
1920         //
1921         // The semaphore has been incremented, but while we were waiting
1922         // another thread suspended us. We don't want to continue running
1923         // while suspended because that would surprise the thread that
1924         // suspended us.
1925         //
1926         ::SEM_POST(sig_sem);
1927 
1928         thread->java_suspend_self();
1929       }
1930     } while (threadIsSuspended);
1931   }
1932 }
1933 
1934 int os::signal_lookup() {
1935   return check_pending_signals(false);
1936 }
1937 
1938 int os::signal_wait() {
1939   return check_pending_signals(true);
1940 }
1941 
1942 ////////////////////////////////////////////////////////////////////////////////
1943 // Virtual Memory
1944 
1945 int os::vm_page_size() {
1946   // Seems redundant as all get out
1947   assert(os::Bsd::page_size() != -1, "must call os::init");
1948   return os::Bsd::page_size();
1949 }
1950 
1951 // Solaris allocates memory by pages.
1952 int os::vm_allocation_granularity() {
1953   assert(os::Bsd::page_size() != -1, "must call os::init");
1954   return os::Bsd::page_size();
1955 }
1956 
1957 // Rationale behind this function:
1958 //  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1959 //  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1960 //  samples for JITted code. Here we create private executable mapping over the code cache
1961 //  and then we can use standard (well, almost, as mapping can change) way to provide
1962 //  info for the reporting script by storing timestamp and location of symbol
1963 void bsd_wrap_code(char* base, size_t size) {
1964   static volatile jint cnt = 0;
1965 
1966   if (!UseOprofile) {
1967     return;
1968   }
1969 
1970   char buf[PATH_MAX + 1];
1971   int num = Atomic::add(1, &cnt);
1972 
1973   snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1974            os::get_temp_directory(), os::current_process_id(), num);
1975   unlink(buf);
1976 
1977   int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1978 
1979   if (fd != -1) {
1980     off_t rv = ::lseek(fd, size-2, SEEK_SET);
1981     if (rv != (off_t)-1) {
1982       if (::write(fd, "", 1) == 1) {
1983         mmap(base, size,
1984              PROT_READ|PROT_WRITE|PROT_EXEC,
1985              MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1986       }
1987     }
1988     ::close(fd);
1989     unlink(buf);
1990   }
1991 }
1992 
1993 // NOTE: Bsd kernel does not really reserve the pages for us.
1994 //       All it does is to check if there are enough free pages
1995 //       left at the time of mmap(). This could be a potential
1996 //       problem.
1997 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1998   int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1999 #ifdef __OpenBSD__
2000   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2001   return ::mprotect(addr, size, prot) == 0;
2002 #else
2003   uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2004                                    MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2005   return res != (uintptr_t) MAP_FAILED;
2006 #endif
2007 }
2008 
2009 
2010 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2011                        bool exec) {
2012   return commit_memory(addr, size, exec);
2013 }
2014 
2015 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2016 }
2017 
2018 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2019   ::madvise(addr, bytes, MADV_DONTNEED);
2020 }
2021 
2022 void os::numa_make_global(char *addr, size_t bytes) {
2023 }
2024 
2025 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2026 }
2027 
2028 bool os::numa_topology_changed()   { return false; }
2029 
2030 size_t os::numa_get_groups_num() {
2031   return 1;
2032 }
2033 
2034 int os::numa_get_group_id() {
2035   return 0;
2036 }
2037 
2038 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2039   if (size > 0) {
2040     ids[0] = 0;
2041     return 1;
2042   }
2043   return 0;
2044 }
2045 
2046 bool os::get_page_info(char *start, page_info* info) {
2047   return false;
2048 }
2049 
2050 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2051   return end;
2052 }
2053 
2054 
2055 bool os::pd_uncommit_memory(char* addr, size_t size) {
2056 #ifdef __OpenBSD__
2057   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2058   return ::mprotect(addr, size, PROT_NONE) == 0;
2059 #else
2060   uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2061                 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2062   return res  != (uintptr_t) MAP_FAILED;
2063 #endif
2064 }
2065 
2066 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2067   return os::commit_memory(addr, size);
2068 }
2069 
2070 // If this is a growable mapping, remove the guard pages entirely by
2071 // munmap()ping them.  If not, just call uncommit_memory().
2072 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2073   return os::uncommit_memory(addr, size);
2074 }
2075 
2076 static address _highest_vm_reserved_address = NULL;
2077 
2078 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2079 // at 'requested_addr'. If there are existing memory mappings at the same
2080 // location, however, they will be overwritten. If 'fixed' is false,
2081 // 'requested_addr' is only treated as a hint, the return value may or
2082 // may not start from the requested address. Unlike Bsd mmap(), this
2083 // function returns NULL to indicate failure.
2084 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2085   char * addr;
2086   int flags;
2087 
2088   flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2089   if (fixed) {
2090     assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2091     flags |= MAP_FIXED;
2092   }
2093 
2094   // Map uncommitted pages PROT_READ and PROT_WRITE, change access
2095   // to PROT_EXEC if executable when we commit the page.
2096   addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
2097                        flags, -1, 0);
2098 
2099   if (addr != MAP_FAILED) {
2100     // anon_mmap() should only get called during VM initialization,
2101     // don't need lock (actually we can skip locking even it can be called
2102     // from multiple threads, because _highest_vm_reserved_address is just a
2103     // hint about the upper limit of non-stack memory regions.)
2104     if ((address)addr + bytes > _highest_vm_reserved_address) {
2105       _highest_vm_reserved_address = (address)addr + bytes;
2106     }
2107   }
2108 
2109   return addr == MAP_FAILED ? NULL : addr;
2110 }
2111 
2112 // Don't update _highest_vm_reserved_address, because there might be memory
2113 // regions above addr + size. If so, releasing a memory region only creates
2114 // a hole in the address space, it doesn't help prevent heap-stack collision.
2115 //
2116 static int anon_munmap(char * addr, size_t size) {
2117   return ::munmap(addr, size) == 0;
2118 }
2119 
2120 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2121                          size_t alignment_hint) {
2122   return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2123 }
2124 
2125 bool os::pd_release_memory(char* addr, size_t size) {
2126   return anon_munmap(addr, size);
2127 }
2128 
2129 static address highest_vm_reserved_address() {
2130   return _highest_vm_reserved_address;
2131 }
2132 
2133 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2134   // Bsd wants the mprotect address argument to be page aligned.
2135   char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2136 
2137   // According to SUSv3, mprotect() should only be used with mappings
2138   // established by mmap(), and mmap() always maps whole pages. Unaligned
2139   // 'addr' likely indicates problem in the VM (e.g. trying to change
2140   // protection of malloc'ed or statically allocated memory). Check the
2141   // caller if you hit this assert.
2142   assert(addr == bottom, "sanity check");
2143 
2144   size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2145   return ::mprotect(bottom, size, prot) == 0;
2146 }
2147 
2148 // Set protections specified
2149 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2150                         bool is_committed) {
2151   unsigned int p = 0;
2152   switch (prot) {
2153   case MEM_PROT_NONE: p = PROT_NONE; break;
2154   case MEM_PROT_READ: p = PROT_READ; break;
2155   case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
2156   case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2157   default:
2158     ShouldNotReachHere();
2159   }
2160   // is_committed is unused.
2161   return bsd_mprotect(addr, bytes, p);
2162 }
2163 
2164 bool os::guard_memory(char* addr, size_t size) {
2165   return bsd_mprotect(addr, size, PROT_NONE);
2166 }
2167 
2168 bool os::unguard_memory(char* addr, size_t size) {
2169   return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2170 }
2171 
2172 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2173   return false;
2174 }
2175 
2176 /*
2177 * Set the coredump_filter bits to include largepages in core dump (bit 6)
2178 *
2179 * From the coredump_filter documentation:
2180 *
2181 * - (bit 0) anonymous private memory
2182 * - (bit 1) anonymous shared memory
2183 * - (bit 2) file-backed private memory
2184 * - (bit 3) file-backed shared memory
2185 * - (bit 4) ELF header pages in file-backed private memory areas (it is
2186 *           effective only if the bit 2 is cleared)
2187 * - (bit 5) hugetlb private memory
2188 * - (bit 6) hugetlb shared memory
2189 */
2190 static void set_coredump_filter(void) {
2191   FILE *f;
2192   long cdm;
2193 
2194   if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
2195     return;
2196   }
2197 
2198   if (fscanf(f, "%lx", &cdm) != 1) {
2199     fclose(f);
2200     return;
2201   }
2202 
2203   rewind(f);
2204 
2205   if ((cdm & LARGEPAGES_BIT) == 0) {
2206     cdm |= LARGEPAGES_BIT;
2207     fprintf(f, "%#lx", cdm);
2208   }
2209 
2210   fclose(f);
2211 }
2212 
2213 // Large page support
2214 
2215 static size_t _large_page_size = 0;
2216 
2217 void os::large_page_init() {
2218 }
2219 
2220 
2221 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2222   // "exec" is passed in but not used.  Creating the shared image for
2223   // the code cache doesn't have an SHM_X executable permission to check.
2224   assert(UseLargePages && UseSHM, "only for SHM large pages");
2225 
2226   key_t key = IPC_PRIVATE;
2227   char *addr;
2228 
2229   bool warn_on_failure = UseLargePages &&
2230                         (!FLAG_IS_DEFAULT(UseLargePages) ||
2231                          !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2232                         );
2233   char msg[128];
2234 
2235   // Create a large shared memory region to attach to based on size.
2236   // Currently, size is the total size of the heap
2237   int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2238   if (shmid == -1) {
2239      // Possible reasons for shmget failure:
2240      // 1. shmmax is too small for Java heap.
2241      //    > check shmmax value: cat /proc/sys/kernel/shmmax
2242      //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2243      // 2. not enough large page memory.
2244      //    > check available large pages: cat /proc/meminfo
2245      //    > increase amount of large pages:
2246      //          echo new_value > /proc/sys/vm/nr_hugepages
2247      //      Note 1: different Bsd may use different name for this property,
2248      //            e.g. on Redhat AS-3 it is "hugetlb_pool".
2249      //      Note 2: it's possible there's enough physical memory available but
2250      //            they are so fragmented after a long run that they can't
2251      //            coalesce into large pages. Try to reserve large pages when
2252      //            the system is still "fresh".
2253      if (warn_on_failure) {
2254        jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2255        warning(msg);
2256      }
2257      return NULL;
2258   }
2259 
2260   // attach to the region
2261   addr = (char*)shmat(shmid, req_addr, 0);
2262   int err = errno;
2263 
2264   // Remove shmid. If shmat() is successful, the actual shared memory segment
2265   // will be deleted when it's detached by shmdt() or when the process
2266   // terminates. If shmat() is not successful this will remove the shared
2267   // segment immediately.
2268   shmctl(shmid, IPC_RMID, NULL);
2269 
2270   if ((intptr_t)addr == -1) {
2271      if (warn_on_failure) {
2272        jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2273        warning(msg);
2274      }
2275      return NULL;
2276   }
2277 
2278   return addr;
2279 }
2280 
2281 bool os::release_memory_special(char* base, size_t bytes) {
2282   // detaching the SHM segment will also delete it, see reserve_memory_special()
2283   int rslt = shmdt(base);
2284   return rslt == 0;
2285 }
2286 
2287 size_t os::large_page_size() {
2288   return _large_page_size;
2289 }
2290 
2291 // HugeTLBFS allows application to commit large page memory on demand;
2292 // with SysV SHM the entire memory region must be allocated as shared
2293 // memory.
2294 bool os::can_commit_large_page_memory() {
2295   return UseHugeTLBFS;
2296 }
2297 
2298 bool os::can_execute_large_page_memory() {
2299   return UseHugeTLBFS;
2300 }
2301 
2302 // Reserve memory at an arbitrary address, only if that area is
2303 // available (and not reserved for something else).
2304 
2305 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2306   const int max_tries = 10;
2307   char* base[max_tries];
2308   size_t size[max_tries];
2309   const size_t gap = 0x000000;
2310 
2311   // Assert only that the size is a multiple of the page size, since
2312   // that's all that mmap requires, and since that's all we really know
2313   // about at this low abstraction level.  If we need higher alignment,
2314   // we can either pass an alignment to this method or verify alignment
2315   // in one of the methods further up the call chain.  See bug 5044738.
2316   assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2317 
2318   // Repeatedly allocate blocks until the block is allocated at the
2319   // right spot. Give up after max_tries. Note that reserve_memory() will
2320   // automatically update _highest_vm_reserved_address if the call is
2321   // successful. The variable tracks the highest memory address every reserved
2322   // by JVM. It is used to detect heap-stack collision if running with
2323   // fixed-stack BsdThreads. Because here we may attempt to reserve more
2324   // space than needed, it could confuse the collision detecting code. To
2325   // solve the problem, save current _highest_vm_reserved_address and
2326   // calculate the correct value before return.
2327   address old_highest = _highest_vm_reserved_address;
2328 
2329   // Bsd mmap allows caller to pass an address as hint; give it a try first,
2330   // if kernel honors the hint then we can return immediately.
2331   char * addr = anon_mmap(requested_addr, bytes, false);
2332   if (addr == requested_addr) {
2333      return requested_addr;
2334   }
2335 
2336   if (addr != NULL) {
2337      // mmap() is successful but it fails to reserve at the requested address
2338      anon_munmap(addr, bytes);
2339   }
2340 
2341   int i;
2342   for (i = 0; i < max_tries; ++i) {
2343     base[i] = reserve_memory(bytes);
2344 
2345     if (base[i] != NULL) {
2346       // Is this the block we wanted?
2347       if (base[i] == requested_addr) {
2348         size[i] = bytes;
2349         break;
2350       }
2351 
2352       // Does this overlap the block we wanted? Give back the overlapped
2353       // parts and try again.
2354 
2355       size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2356       if (top_overlap >= 0 && top_overlap < bytes) {
2357         unmap_memory(base[i], top_overlap);
2358         base[i] += top_overlap;
2359         size[i] = bytes - top_overlap;
2360       } else {
2361         size_t bottom_overlap = base[i] + bytes - requested_addr;
2362         if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2363           unmap_memory(requested_addr, bottom_overlap);
2364           size[i] = bytes - bottom_overlap;
2365         } else {
2366           size[i] = bytes;
2367         }
2368       }
2369     }
2370   }
2371 
2372   // Give back the unused reserved pieces.
2373 
2374   for (int j = 0; j < i; ++j) {
2375     if (base[j] != NULL) {
2376       unmap_memory(base[j], size[j]);
2377     }
2378   }
2379 
2380   if (i < max_tries) {
2381     _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2382     return requested_addr;
2383   } else {
2384     _highest_vm_reserved_address = old_highest;
2385     return NULL;
2386   }
2387 }
2388 
2389 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2390   RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2391 }
2392 
2393 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2394 // Solaris uses poll(), bsd uses park().
2395 // Poll() is likely a better choice, assuming that Thread.interrupt()
2396 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2397 // SIGSEGV, see 4355769.
2398 
2399 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2400   assert(thread == Thread::current(),  "thread consistency check");
2401 
2402   ParkEvent * const slp = thread->_SleepEvent ;
2403   slp->reset() ;
2404   OrderAccess::fence() ;
2405 
2406   if (interruptible) {
2407     jlong prevtime = javaTimeNanos();
2408 
2409     for (;;) {
2410       if (os::is_interrupted(thread, true)) {
2411         return OS_INTRPT;
2412       }
2413 
2414       jlong newtime = javaTimeNanos();
2415 
2416       if (newtime - prevtime < 0) {
2417         // time moving backwards, should only happen if no monotonic clock
2418         // not a guarantee() because JVM should not abort on kernel/glibc bugs
2419         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2420       } else {
2421         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2422       }
2423 
2424       if(millis <= 0) {
2425         return OS_OK;
2426       }
2427 
2428       prevtime = newtime;
2429 
2430       {
2431         assert(thread->is_Java_thread(), "sanity check");
2432         JavaThread *jt = (JavaThread *) thread;
2433         ThreadBlockInVM tbivm(jt);
2434         OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2435 
2436         jt->set_suspend_equivalent();
2437         // cleared by handle_special_suspend_equivalent_condition() or
2438         // java_suspend_self() via check_and_wait_while_suspended()
2439 
2440         slp->park(millis);
2441 
2442         // were we externally suspended while we were waiting?
2443         jt->check_and_wait_while_suspended();
2444       }
2445     }
2446   } else {
2447     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2448     jlong prevtime = javaTimeNanos();
2449 
2450     for (;;) {
2451       // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2452       // the 1st iteration ...
2453       jlong newtime = javaTimeNanos();
2454 
2455       if (newtime - prevtime < 0) {
2456         // time moving backwards, should only happen if no monotonic clock
2457         // not a guarantee() because JVM should not abort on kernel/glibc bugs
2458         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2459       } else {
2460         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2461       }
2462 
2463       if(millis <= 0) break ;
2464 
2465       prevtime = newtime;
2466       slp->park(millis);
2467     }
2468     return OS_OK ;
2469   }
2470 }
2471 
2472 int os::naked_sleep() {
2473   // %% make the sleep time an integer flag. for now use 1 millisec.
2474   return os::sleep(Thread::current(), 1, false);
2475 }
2476 
2477 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2478 void os::infinite_sleep() {
2479   while (true) {    // sleep forever ...
2480     ::sleep(100);   // ... 100 seconds at a time
2481   }
2482 }
2483 
2484 // Used to convert frequent JVM_Yield() to nops
2485 bool os::dont_yield() {
2486   return DontYieldALot;
2487 }
2488 
2489 void os::yield() {
2490   sched_yield();
2491 }
2492 
2493 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2494 
2495 void os::yield_all(int attempts) {
2496   // Yields to all threads, including threads with lower priorities
2497   // Threads on Bsd are all with same priority. The Solaris style
2498   // os::yield_all() with nanosleep(1ms) is not necessary.
2499   sched_yield();
2500 }
2501 
2502 // Called from the tight loops to possibly influence time-sharing heuristics
2503 void os::loop_breaker(int attempts) {
2504   os::yield_all(attempts);
2505 }
2506 
2507 ////////////////////////////////////////////////////////////////////////////////
2508 // thread priority support
2509 
2510 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2511 // only supports dynamic priority, static priority must be zero. For real-time
2512 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2513 // However, for large multi-threaded applications, SCHED_RR is not only slower
2514 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2515 // of 5 runs - Sep 2005).
2516 //
2517 // The following code actually changes the niceness of kernel-thread/LWP. It
2518 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2519 // not the entire user process, and user level threads are 1:1 mapped to kernel
2520 // threads. It has always been the case, but could change in the future. For
2521 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2522 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2523 
2524 #if !defined(__APPLE__)
2525 int os::java_to_os_priority[CriticalPriority + 1] = {
2526   19,              // 0 Entry should never be used
2527 
2528    0,              // 1 MinPriority
2529    3,              // 2
2530    6,              // 3
2531 
2532   10,              // 4
2533   15,              // 5 NormPriority
2534   18,              // 6
2535 
2536   21,              // 7
2537   25,              // 8
2538   28,              // 9 NearMaxPriority
2539 
2540   31,              // 10 MaxPriority
2541 
2542   31               // 11 CriticalPriority
2543 };
2544 #else
2545 /* Using Mach high-level priority assignments */
2546 int os::java_to_os_priority[CriticalPriority + 1] = {
2547    0,              // 0 Entry should never be used (MINPRI_USER)
2548 
2549   27,              // 1 MinPriority
2550   28,              // 2
2551   29,              // 3
2552 
2553   30,              // 4
2554   31,              // 5 NormPriority (BASEPRI_DEFAULT)
2555   32,              // 6
2556 
2557   33,              // 7
2558   34,              // 8
2559   35,              // 9 NearMaxPriority
2560 
2561   36,              // 10 MaxPriority
2562 
2563   36               // 11 CriticalPriority
2564 };
2565 #endif
2566 
2567 static int prio_init() {
2568   if (ThreadPriorityPolicy == 1) {
2569     // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2570     // if effective uid is not root. Perhaps, a more elegant way of doing
2571     // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2572     if (geteuid() != 0) {
2573       if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2574         warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2575       }
2576       ThreadPriorityPolicy = 0;
2577     }
2578   }
2579   if (UseCriticalJavaThreadPriority) {
2580     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2581   }
2582   return 0;
2583 }
2584 
2585 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2586   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2587 
2588 #ifdef __OpenBSD__
2589   // OpenBSD pthread_setprio starves low priority threads
2590   return OS_OK;
2591 #elif defined(__FreeBSD__)
2592   int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2593 #elif defined(__APPLE__) || defined(__NetBSD__)
2594   struct sched_param sp;
2595   int policy;
2596   pthread_t self = pthread_self();
2597 
2598   if (pthread_getschedparam(self, &policy, &sp) != 0)
2599     return OS_ERR;
2600 
2601   sp.sched_priority = newpri;
2602   if (pthread_setschedparam(self, policy, &sp) != 0)
2603     return OS_ERR;
2604 
2605   return OS_OK;
2606 #else
2607   int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2608   return (ret == 0) ? OS_OK : OS_ERR;
2609 #endif
2610 }
2611 
2612 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2613   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2614     *priority_ptr = java_to_os_priority[NormPriority];
2615     return OS_OK;
2616   }
2617 
2618   errno = 0;
2619 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2620   *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2621 #elif defined(__APPLE__) || defined(__NetBSD__)
2622   int policy;
2623   struct sched_param sp;
2624 
2625   pthread_getschedparam(pthread_self(), &policy, &sp);
2626   *priority_ptr = sp.sched_priority;
2627 #else
2628   *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2629 #endif
2630   return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2631 }
2632 
2633 // Hint to the underlying OS that a task switch would not be good.
2634 // Void return because it's a hint and can fail.
2635 void os::hint_no_preempt() {}
2636 
2637 ////////////////////////////////////////////////////////////////////////////////
2638 // suspend/resume support
2639 
2640 //  the low-level signal-based suspend/resume support is a remnant from the
2641 //  old VM-suspension that used to be for java-suspension, safepoints etc,
2642 //  within hotspot. Now there is a single use-case for this:
2643 //    - calling get_thread_pc() on the VMThread by the flat-profiler task
2644 //      that runs in the watcher thread.
2645 //  The remaining code is greatly simplified from the more general suspension
2646 //  code that used to be used.
2647 //
2648 //  The protocol is quite simple:
2649 //  - suspend:
2650 //      - sends a signal to the target thread
2651 //      - polls the suspend state of the osthread using a yield loop
2652 //      - target thread signal handler (SR_handler) sets suspend state
2653 //        and blocks in sigsuspend until continued
2654 //  - resume:
2655 //      - sets target osthread state to continue
2656 //      - sends signal to end the sigsuspend loop in the SR_handler
2657 //
2658 //  Note that the SR_lock plays no role in this suspend/resume protocol.
2659 //
2660 
2661 static void resume_clear_context(OSThread *osthread) {
2662   osthread->set_ucontext(NULL);
2663   osthread->set_siginfo(NULL);
2664 
2665   // notify the suspend action is completed, we have now resumed
2666   osthread->sr.clear_suspended();
2667 }
2668 
2669 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2670   osthread->set_ucontext(context);
2671   osthread->set_siginfo(siginfo);
2672 }
2673 
2674 //
2675 // Handler function invoked when a thread's execution is suspended or
2676 // resumed. We have to be careful that only async-safe functions are
2677 // called here (Note: most pthread functions are not async safe and
2678 // should be avoided.)
2679 //
2680 // Note: sigwait() is a more natural fit than sigsuspend() from an
2681 // interface point of view, but sigwait() prevents the signal hander
2682 // from being run. libpthread would get very confused by not having
2683 // its signal handlers run and prevents sigwait()'s use with the
2684 // mutex granting granting signal.
2685 //
2686 // Currently only ever called on the VMThread
2687 //
2688 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2689   // Save and restore errno to avoid confusing native code with EINTR
2690   // after sigsuspend.
2691   int old_errno = errno;
2692 
2693   Thread* thread = Thread::current();
2694   OSThread* osthread = thread->osthread();
2695   assert(thread->is_VM_thread(), "Must be VMThread");
2696   // read current suspend action
2697   int action = osthread->sr.suspend_action();
2698   if (action == SR_SUSPEND) {
2699     suspend_save_context(osthread, siginfo, context);
2700 
2701     // Notify the suspend action is about to be completed. do_suspend()
2702     // waits until SR_SUSPENDED is set and then returns. We will wait
2703     // here for a resume signal and that completes the suspend-other
2704     // action. do_suspend/do_resume is always called as a pair from
2705     // the same thread - so there are no races
2706 
2707     // notify the caller
2708     osthread->sr.set_suspended();
2709 
2710     sigset_t suspend_set;  // signals for sigsuspend()
2711 
2712     // get current set of blocked signals and unblock resume signal
2713     pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2714     sigdelset(&suspend_set, SR_signum);
2715 
2716     // wait here until we are resumed
2717     do {
2718       sigsuspend(&suspend_set);
2719       // ignore all returns until we get a resume signal
2720     } while (osthread->sr.suspend_action() != SR_CONTINUE);
2721 
2722     resume_clear_context(osthread);
2723 
2724   } else {
2725     assert(action == SR_CONTINUE, "unexpected sr action");
2726     // nothing special to do - just leave the handler
2727   }
2728 
2729   errno = old_errno;
2730 }
2731 
2732 
2733 static int SR_initialize() {
2734   struct sigaction act;
2735   char *s;
2736   /* Get signal number to use for suspend/resume */
2737   if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2738     int sig = ::strtol(s, 0, 10);
2739     if (sig > 0 || sig < NSIG) {
2740         SR_signum = sig;
2741     }
2742   }
2743 
2744   assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2745         "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2746 
2747   sigemptyset(&SR_sigset);
2748   sigaddset(&SR_sigset, SR_signum);
2749 
2750   /* Set up signal handler for suspend/resume */
2751   act.sa_flags = SA_RESTART|SA_SIGINFO;
2752   act.sa_handler = (void (*)(int)) SR_handler;
2753 
2754   // SR_signum is blocked by default.
2755   // 4528190 - We also need to block pthread restart signal (32 on all
2756   // supported Bsd platforms). Note that BsdThreads need to block
2757   // this signal for all threads to work properly. So we don't have
2758   // to use hard-coded signal number when setting up the mask.
2759   pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2760 
2761   if (sigaction(SR_signum, &act, 0) == -1) {
2762     return -1;
2763   }
2764 
2765   // Save signal flag
2766   os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2767   return 0;
2768 }
2769 
2770 static int SR_finalize() {
2771   return 0;
2772 }
2773 
2774 
2775 // returns true on success and false on error - really an error is fatal
2776 // but this seems the normal response to library errors
2777 static bool do_suspend(OSThread* osthread) {
2778   // mark as suspended and send signal
2779   osthread->sr.set_suspend_action(SR_SUSPEND);
2780   int status = pthread_kill(osthread->pthread_id(), SR_signum);
2781   assert_status(status == 0, status, "pthread_kill");
2782 
2783   // check status and wait until notified of suspension
2784   if (status == 0) {
2785     for (int i = 0; !osthread->sr.is_suspended(); i++) {
2786       os::yield_all(i);
2787     }
2788     osthread->sr.set_suspend_action(SR_NONE);
2789     return true;
2790   }
2791   else {
2792     osthread->sr.set_suspend_action(SR_NONE);
2793     return false;
2794   }
2795 }
2796 
2797 static void do_resume(OSThread* osthread) {
2798   assert(osthread->sr.is_suspended(), "thread should be suspended");
2799   osthread->sr.set_suspend_action(SR_CONTINUE);
2800 
2801   int status = pthread_kill(osthread->pthread_id(), SR_signum);
2802   assert_status(status == 0, status, "pthread_kill");
2803   // check status and wait unit notified of resumption
2804   if (status == 0) {
2805     for (int i = 0; osthread->sr.is_suspended(); i++) {
2806       os::yield_all(i);
2807     }
2808   }
2809   osthread->sr.set_suspend_action(SR_NONE);
2810 }
2811 
2812 ////////////////////////////////////////////////////////////////////////////////
2813 // interrupt support
2814 
2815 void os::interrupt(Thread* thread) {
2816   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2817     "possibility of dangling Thread pointer");
2818 
2819   OSThread* osthread = thread->osthread();
2820 
2821   if (!osthread->interrupted()) {
2822     osthread->set_interrupted(true);
2823     // More than one thread can get here with the same value of osthread,
2824     // resulting in multiple notifications.  We do, however, want the store
2825     // to interrupted() to be visible to other threads before we execute unpark().
2826     OrderAccess::fence();
2827     ParkEvent * const slp = thread->_SleepEvent ;
2828     if (slp != NULL) slp->unpark() ;
2829   }
2830 
2831   // For JSR166. Unpark even if interrupt status already was set
2832   if (thread->is_Java_thread())
2833     ((JavaThread*)thread)->parker()->unpark();
2834 
2835   ParkEvent * ev = thread->_ParkEvent ;
2836   if (ev != NULL) ev->unpark() ;
2837 
2838 }
2839 
2840 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2841   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2842     "possibility of dangling Thread pointer");
2843 
2844   OSThread* osthread = thread->osthread();
2845 
2846   bool interrupted = osthread->interrupted();
2847 
2848   if (interrupted && clear_interrupted) {
2849     osthread->set_interrupted(false);
2850     // consider thread->_SleepEvent->reset() ... optional optimization
2851   }
2852 
2853   return interrupted;
2854 }
2855 
2856 ///////////////////////////////////////////////////////////////////////////////////
2857 // signal handling (except suspend/resume)
2858 
2859 // This routine may be used by user applications as a "hook" to catch signals.
2860 // The user-defined signal handler must pass unrecognized signals to this
2861 // routine, and if it returns true (non-zero), then the signal handler must
2862 // return immediately.  If the flag "abort_if_unrecognized" is true, then this
2863 // routine will never retun false (zero), but instead will execute a VM panic
2864 // routine kill the process.
2865 //
2866 // If this routine returns false, it is OK to call it again.  This allows
2867 // the user-defined signal handler to perform checks either before or after
2868 // the VM performs its own checks.  Naturally, the user code would be making
2869 // a serious error if it tried to handle an exception (such as a null check
2870 // or breakpoint) that the VM was generating for its own correct operation.
2871 //
2872 // This routine may recognize any of the following kinds of signals:
2873 //    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2874 // It should be consulted by handlers for any of those signals.
2875 //
2876 // The caller of this routine must pass in the three arguments supplied
2877 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2878 // field of the structure passed to sigaction().  This routine assumes that
2879 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2880 //
2881 // Note that the VM will print warnings if it detects conflicting signal
2882 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2883 //
2884 extern "C" JNIEXPORT int
2885 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2886                         void* ucontext, int abort_if_unrecognized);
2887 
2888 void signalHandler(int sig, siginfo_t* info, void* uc) {
2889   assert(info != NULL && uc != NULL, "it must be old kernel");
2890   int orig_errno = errno;  // Preserve errno value over signal handler.
2891   JVM_handle_bsd_signal(sig, info, uc, true);
2892   errno = orig_errno;
2893 }
2894 
2895 
2896 // This boolean allows users to forward their own non-matching signals
2897 // to JVM_handle_bsd_signal, harmlessly.
2898 bool os::Bsd::signal_handlers_are_installed = false;
2899 
2900 // For signal-chaining
2901 struct sigaction os::Bsd::sigact[MAXSIGNUM];
2902 unsigned int os::Bsd::sigs = 0;
2903 bool os::Bsd::libjsig_is_loaded = false;
2904 typedef struct sigaction *(*get_signal_t)(int);
2905 get_signal_t os::Bsd::get_signal_action = NULL;
2906 
2907 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2908   struct sigaction *actp = NULL;
2909 
2910   if (libjsig_is_loaded) {
2911     // Retrieve the old signal handler from libjsig
2912     actp = (*get_signal_action)(sig);
2913   }
2914   if (actp == NULL) {
2915     // Retrieve the preinstalled signal handler from jvm
2916     actp = get_preinstalled_handler(sig);
2917   }
2918 
2919   return actp;
2920 }
2921 
2922 static bool call_chained_handler(struct sigaction *actp, int sig,
2923                                  siginfo_t *siginfo, void *context) {
2924   // Call the old signal handler
2925   if (actp->sa_handler == SIG_DFL) {
2926     // It's more reasonable to let jvm treat it as an unexpected exception
2927     // instead of taking the default action.
2928     return false;
2929   } else if (actp->sa_handler != SIG_IGN) {
2930     if ((actp->sa_flags & SA_NODEFER) == 0) {
2931       // automaticlly block the signal
2932       sigaddset(&(actp->sa_mask), sig);
2933     }
2934 
2935     sa_handler_t hand;
2936     sa_sigaction_t sa;
2937     bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2938     // retrieve the chained handler
2939     if (siginfo_flag_set) {
2940       sa = actp->sa_sigaction;
2941     } else {
2942       hand = actp->sa_handler;
2943     }
2944 
2945     if ((actp->sa_flags & SA_RESETHAND) != 0) {
2946       actp->sa_handler = SIG_DFL;
2947     }
2948 
2949     // try to honor the signal mask
2950     sigset_t oset;
2951     pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2952 
2953     // call into the chained handler
2954     if (siginfo_flag_set) {
2955       (*sa)(sig, siginfo, context);
2956     } else {
2957       (*hand)(sig);
2958     }
2959 
2960     // restore the signal mask
2961     pthread_sigmask(SIG_SETMASK, &oset, 0);
2962   }
2963   // Tell jvm's signal handler the signal is taken care of.
2964   return true;
2965 }
2966 
2967 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2968   bool chained = false;
2969   // signal-chaining
2970   if (UseSignalChaining) {
2971     struct sigaction *actp = get_chained_signal_action(sig);
2972     if (actp != NULL) {
2973       chained = call_chained_handler(actp, sig, siginfo, context);
2974     }
2975   }
2976   return chained;
2977 }
2978 
2979 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
2980   if ((( (unsigned int)1 << sig ) & sigs) != 0) {
2981     return &sigact[sig];
2982   }
2983   return NULL;
2984 }
2985 
2986 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
2987   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2988   sigact[sig] = oldAct;
2989   sigs |= (unsigned int)1 << sig;
2990 }
2991 
2992 // for diagnostic
2993 int os::Bsd::sigflags[MAXSIGNUM];
2994 
2995 int os::Bsd::get_our_sigflags(int sig) {
2996   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2997   return sigflags[sig];
2998 }
2999 
3000 void os::Bsd::set_our_sigflags(int sig, int flags) {
3001   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3002   sigflags[sig] = flags;
3003 }
3004 
3005 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3006   // Check for overwrite.
3007   struct sigaction oldAct;
3008   sigaction(sig, (struct sigaction*)NULL, &oldAct);
3009 
3010   void* oldhand = oldAct.sa_sigaction
3011                 ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
3012                 : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
3013   if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3014       oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3015       oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3016     if (AllowUserSignalHandlers || !set_installed) {
3017       // Do not overwrite; user takes responsibility to forward to us.
3018       return;
3019     } else if (UseSignalChaining) {
3020       // save the old handler in jvm
3021       save_preinstalled_handler(sig, oldAct);
3022       // libjsig also interposes the sigaction() call below and saves the
3023       // old sigaction on it own.
3024     } else {
3025       fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3026                     "%#lx for signal %d.", (long)oldhand, sig));
3027     }
3028   }
3029 
3030   struct sigaction sigAct;
3031   sigfillset(&(sigAct.sa_mask));
3032   sigAct.sa_handler = SIG_DFL;
3033   if (!set_installed) {
3034     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3035   } else {
3036     sigAct.sa_sigaction = signalHandler;
3037     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3038   }
3039   // Save flags, which are set by ours
3040   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3041   sigflags[sig] = sigAct.sa_flags;
3042 
3043   int ret = sigaction(sig, &sigAct, &oldAct);
3044   assert(ret == 0, "check");
3045 
3046   void* oldhand2  = oldAct.sa_sigaction
3047                   ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3048                   : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3049   assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3050 }
3051 
3052 // install signal handlers for signals that HotSpot needs to
3053 // handle in order to support Java-level exception handling.
3054 
3055 void os::Bsd::install_signal_handlers() {
3056   if (!signal_handlers_are_installed) {
3057     signal_handlers_are_installed = true;
3058 
3059     // signal-chaining
3060     typedef void (*signal_setting_t)();
3061     signal_setting_t begin_signal_setting = NULL;
3062     signal_setting_t end_signal_setting = NULL;
3063     begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3064                              dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3065     if (begin_signal_setting != NULL) {
3066       end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3067                              dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3068       get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3069                             dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3070       libjsig_is_loaded = true;
3071       assert(UseSignalChaining, "should enable signal-chaining");
3072     }
3073     if (libjsig_is_loaded) {
3074       // Tell libjsig jvm is setting signal handlers
3075       (*begin_signal_setting)();
3076     }
3077 
3078     set_signal_handler(SIGSEGV, true);
3079     set_signal_handler(SIGPIPE, true);
3080     set_signal_handler(SIGBUS, true);
3081     set_signal_handler(SIGILL, true);
3082     set_signal_handler(SIGFPE, true);
3083     set_signal_handler(SIGXFSZ, true);
3084 
3085 #if defined(__APPLE__)
3086     // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3087     // signals caught and handled by the JVM. To work around this, we reset the mach task
3088     // signal handler that's placed on our process by CrashReporter. This disables
3089     // CrashReporter-based reporting.
3090     //
3091     // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3092     // on caught fatal signals.
3093     //
3094     // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3095     // handlers. By replacing the existing task exception handler, we disable gdb's mach
3096     // exception handling, while leaving the standard BSD signal handlers functional.
3097     kern_return_t kr;
3098     kr = task_set_exception_ports(mach_task_self(),
3099         EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3100         MACH_PORT_NULL,
3101         EXCEPTION_STATE_IDENTITY,
3102         MACHINE_THREAD_STATE);
3103 
3104     assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3105 #endif
3106 
3107     if (libjsig_is_loaded) {
3108       // Tell libjsig jvm finishes setting signal handlers
3109       (*end_signal_setting)();
3110     }
3111 
3112     // We don't activate signal checker if libjsig is in place, we trust ourselves
3113     // and if UserSignalHandler is installed all bets are off
3114     if (CheckJNICalls) {
3115       if (libjsig_is_loaded) {
3116         tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3117         check_signals = false;
3118       }
3119       if (AllowUserSignalHandlers) {
3120         tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3121         check_signals = false;
3122       }
3123     }
3124   }
3125 }
3126 
3127 
3128 /////
3129 // glibc on Bsd platform uses non-documented flag
3130 // to indicate, that some special sort of signal
3131 // trampoline is used.
3132 // We will never set this flag, and we should
3133 // ignore this flag in our diagnostic
3134 #ifdef SIGNIFICANT_SIGNAL_MASK
3135 #undef SIGNIFICANT_SIGNAL_MASK
3136 #endif
3137 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3138 
3139 static const char* get_signal_handler_name(address handler,
3140                                            char* buf, int buflen) {
3141   int offset;
3142   bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3143   if (found) {
3144     // skip directory names
3145     const char *p1, *p2;
3146     p1 = buf;
3147     size_t len = strlen(os::file_separator());
3148     while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3149     jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3150   } else {
3151     jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3152   }
3153   return buf;
3154 }
3155 
3156 static void print_signal_handler(outputStream* st, int sig,
3157                                  char* buf, size_t buflen) {
3158   struct sigaction sa;
3159 
3160   sigaction(sig, NULL, &sa);
3161 
3162   // See comment for SIGNIFICANT_SIGNAL_MASK define
3163   sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3164 
3165   st->print("%s: ", os::exception_name(sig, buf, buflen));
3166 
3167   address handler = (sa.sa_flags & SA_SIGINFO)
3168     ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3169     : CAST_FROM_FN_PTR(address, sa.sa_handler);
3170 
3171   if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3172     st->print("SIG_DFL");
3173   } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3174     st->print("SIG_IGN");
3175   } else {
3176     st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3177   }
3178 
3179   st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3180 
3181   address rh = VMError::get_resetted_sighandler(sig);
3182   // May be, handler was resetted by VMError?
3183   if(rh != NULL) {
3184     handler = rh;
3185     sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3186   }
3187 
3188   st->print(", sa_flags="   PTR32_FORMAT, sa.sa_flags);
3189 
3190   // Check: is it our handler?
3191   if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3192      handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3193     // It is our signal handler
3194     // check for flags, reset system-used one!
3195     if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3196       st->print(
3197                 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3198                 os::Bsd::get_our_sigflags(sig));
3199     }
3200   }
3201   st->cr();
3202 }
3203 
3204 
3205 #define DO_SIGNAL_CHECK(sig) \
3206   if (!sigismember(&check_signal_done, sig)) \
3207     os::Bsd::check_signal_handler(sig)
3208 
3209 // This method is a periodic task to check for misbehaving JNI applications
3210 // under CheckJNI, we can add any periodic checks here
3211 
3212 void os::run_periodic_checks() {
3213 
3214   if (check_signals == false) return;
3215 
3216   // SEGV and BUS if overridden could potentially prevent
3217   // generation of hs*.log in the event of a crash, debugging
3218   // such a case can be very challenging, so we absolutely
3219   // check the following for a good measure:
3220   DO_SIGNAL_CHECK(SIGSEGV);
3221   DO_SIGNAL_CHECK(SIGILL);
3222   DO_SIGNAL_CHECK(SIGFPE);
3223   DO_SIGNAL_CHECK(SIGBUS);
3224   DO_SIGNAL_CHECK(SIGPIPE);
3225   DO_SIGNAL_CHECK(SIGXFSZ);
3226 
3227 
3228   // ReduceSignalUsage allows the user to override these handlers
3229   // see comments at the very top and jvm_solaris.h
3230   if (!ReduceSignalUsage) {
3231     DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3232     DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3233     DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3234     DO_SIGNAL_CHECK(BREAK_SIGNAL);
3235   }
3236 
3237   DO_SIGNAL_CHECK(SR_signum);
3238   DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3239 }
3240 
3241 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3242 
3243 static os_sigaction_t os_sigaction = NULL;
3244 
3245 void os::Bsd::check_signal_handler(int sig) {
3246   char buf[O_BUFLEN];
3247   address jvmHandler = NULL;
3248 
3249 
3250   struct sigaction act;
3251   if (os_sigaction == NULL) {
3252     // only trust the default sigaction, in case it has been interposed
3253     os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3254     if (os_sigaction == NULL) return;
3255   }
3256 
3257   os_sigaction(sig, (struct sigaction*)NULL, &act);
3258 
3259 
3260   act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3261 
3262   address thisHandler = (act.sa_flags & SA_SIGINFO)
3263     ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3264     : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3265 
3266 
3267   switch(sig) {
3268   case SIGSEGV:
3269   case SIGBUS:
3270   case SIGFPE:
3271   case SIGPIPE:
3272   case SIGILL:
3273   case SIGXFSZ:
3274     jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3275     break;
3276 
3277   case SHUTDOWN1_SIGNAL:
3278   case SHUTDOWN2_SIGNAL:
3279   case SHUTDOWN3_SIGNAL:
3280   case BREAK_SIGNAL:
3281     jvmHandler = (address)user_handler();
3282     break;
3283 
3284   case INTERRUPT_SIGNAL:
3285     jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3286     break;
3287 
3288   default:
3289     if (sig == SR_signum) {
3290       jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3291     } else {
3292       return;
3293     }
3294     break;
3295   }
3296 
3297   if (thisHandler != jvmHandler) {
3298     tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3299     tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3300     tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3301     // No need to check this sig any longer
3302     sigaddset(&check_signal_done, sig);
3303   } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3304     tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3305     tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3306     tty->print_cr("  found:" PTR32_FORMAT, act.sa_flags);
3307     // No need to check this sig any longer
3308     sigaddset(&check_signal_done, sig);
3309   }
3310 
3311   // Dump all the signal
3312   if (sigismember(&check_signal_done, sig)) {
3313     print_signal_handlers(tty, buf, O_BUFLEN);
3314   }
3315 }
3316 
3317 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3318 
3319 extern bool signal_name(int signo, char* buf, size_t len);
3320 
3321 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3322   if (0 < exception_code && exception_code <= SIGRTMAX) {
3323     // signal
3324     if (!signal_name(exception_code, buf, size)) {
3325       jio_snprintf(buf, size, "SIG%d", exception_code);
3326     }
3327     return buf;
3328   } else {
3329     return NULL;
3330   }
3331 }
3332 
3333 // this is called _before_ the most of global arguments have been parsed
3334 void os::init(void) {
3335   char dummy;   /* used to get a guess on initial stack address */
3336 //  first_hrtime = gethrtime();
3337 
3338   // With BsdThreads the JavaMain thread pid (primordial thread)
3339   // is different than the pid of the java launcher thread.
3340   // So, on Bsd, the launcher thread pid is passed to the VM
3341   // via the sun.java.launcher.pid property.
3342   // Use this property instead of getpid() if it was correctly passed.
3343   // See bug 6351349.
3344   pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3345 
3346   _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3347 
3348   clock_tics_per_sec = CLK_TCK;
3349 
3350   init_random(1234567);
3351 
3352   ThreadCritical::initialize();
3353 
3354   Bsd::set_page_size(getpagesize());
3355   if (Bsd::page_size() == -1) {
3356     fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3357                   strerror(errno)));
3358   }
3359   init_page_sizes((size_t) Bsd::page_size());
3360 
3361   Bsd::initialize_system_info();
3362 
3363   // main_thread points to the aboriginal thread
3364   Bsd::_main_thread = pthread_self();
3365 
3366   Bsd::clock_init();
3367   initial_time_count = os::elapsed_counter();
3368 
3369 #ifdef __APPLE__
3370   // XXXDARWIN
3371   // Work around the unaligned VM callbacks in hotspot's
3372   // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3373   // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3374   // alignment when doing symbol lookup. To work around this, we force early
3375   // binding of all symbols now, thus binding when alignment is known-good.
3376   _dyld_bind_fully_image_containing_address((const void *) &os::init);
3377 #endif
3378 }
3379 
3380 // To install functions for atexit system call
3381 extern "C" {
3382   static void perfMemory_exit_helper() {
3383     perfMemory_exit();
3384   }
3385 }
3386 
3387 // this is called _after_ the global arguments have been parsed
3388 jint os::init_2(void)
3389 {
3390   // Allocate a single page and mark it as readable for safepoint polling
3391   address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3392   guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3393 
3394   os::set_polling_page( polling_page );
3395 
3396 #ifndef PRODUCT
3397   if(Verbose && PrintMiscellaneous)
3398     tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3399 #endif
3400 
3401   if (!UseMembar) {
3402     address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3403     guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3404     os::set_memory_serialize_page( mem_serialize_page );
3405 
3406 #ifndef PRODUCT
3407     if(Verbose && PrintMiscellaneous)
3408       tty->print("[Memory Serialize  Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3409 #endif
3410   }
3411 
3412   os::large_page_init();
3413 
3414   // initialize suspend/resume support - must do this before signal_sets_init()
3415   if (SR_initialize() != 0) {
3416     perror("SR_initialize failed");
3417     return JNI_ERR;
3418   }
3419 
3420   Bsd::signal_sets_init();
3421   Bsd::install_signal_handlers();
3422 
3423   // Check minimum allowable stack size for thread creation and to initialize
3424   // the java system classes, including StackOverflowError - depends on page
3425   // size.  Add a page for compiler2 recursion in main thread.
3426   // Add in 2*BytesPerWord times page size to account for VM stack during
3427   // class initialization depending on 32 or 64 bit VM.
3428   os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3429             (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3430                     2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3431 
3432   size_t threadStackSizeInBytes = ThreadStackSize * K;
3433   if (threadStackSizeInBytes != 0 &&
3434       threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3435         tty->print_cr("\nThe stack size specified is too small, "
3436                       "Specify at least %dk",
3437                       os::Bsd::min_stack_allowed/ K);
3438         return JNI_ERR;
3439   }
3440 
3441   // Make the stack size a multiple of the page size so that
3442   // the yellow/red zones can be guarded.
3443   JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3444         vm_page_size()));
3445 
3446   if (MaxFDLimit) {
3447     // set the number of file descriptors to max. print out error
3448     // if getrlimit/setrlimit fails but continue regardless.
3449     struct rlimit nbr_files;
3450     int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3451     if (status != 0) {
3452       if (PrintMiscellaneous && (Verbose || WizardMode))
3453         perror("os::init_2 getrlimit failed");
3454     } else {
3455       nbr_files.rlim_cur = nbr_files.rlim_max;
3456 
3457 #ifdef __APPLE__
3458       // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3459       // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3460       // be used instead
3461       nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3462 #endif
3463 
3464       status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3465       if (status != 0) {
3466         if (PrintMiscellaneous && (Verbose || WizardMode))
3467           perror("os::init_2 setrlimit failed");
3468       }
3469     }
3470   }
3471 
3472   // at-exit methods are called in the reverse order of their registration.
3473   // atexit functions are called on return from main or as a result of a
3474   // call to exit(3C). There can be only 32 of these functions registered
3475   // and atexit() does not set errno.
3476 
3477   if (PerfAllowAtExitRegistration) {
3478     // only register atexit functions if PerfAllowAtExitRegistration is set.
3479     // atexit functions can be delayed until process exit time, which
3480     // can be problematic for embedded VM situations. Embedded VMs should
3481     // call DestroyJavaVM() to assure that VM resources are released.
3482 
3483     // note: perfMemory_exit_helper atexit function may be removed in
3484     // the future if the appropriate cleanup code can be added to the
3485     // VM_Exit VMOperation's doit method.
3486     if (atexit(perfMemory_exit_helper) != 0) {
3487       warning("os::init2 atexit(perfMemory_exit_helper) failed");
3488     }
3489   }
3490 
3491   // initialize thread priority policy
3492   prio_init();
3493 
3494 #ifdef __APPLE__
3495   // dynamically link to objective c gc registration
3496   void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3497   if (handleLibObjc != NULL) {
3498     objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3499   }
3500 #endif
3501 
3502   return JNI_OK;
3503 }
3504 
3505 // this is called at the end of vm_initialization
3506 void os::init_3(void) { }
3507 
3508 // Mark the polling page as unreadable
3509 void os::make_polling_page_unreadable(void) {
3510   if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3511     fatal("Could not disable polling page");
3512 };
3513 
3514 // Mark the polling page as readable
3515 void os::make_polling_page_readable(void) {
3516   if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3517     fatal("Could not enable polling page");
3518   }
3519 };
3520 
3521 int os::active_processor_count() {
3522   return _processor_count;
3523 }
3524 
3525 void os::set_native_thread_name(const char *name) {
3526 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3527   // This is only supported in Snow Leopard and beyond
3528   if (name != NULL) {
3529     // Add a "Java: " prefix to the name
3530     char buf[MAXTHREADNAMESIZE];
3531     snprintf(buf, sizeof(buf), "Java: %s", name);
3532     pthread_setname_np(buf);
3533   }
3534 #endif
3535 }
3536 
3537 bool os::distribute_processes(uint length, uint* distribution) {
3538   // Not yet implemented.
3539   return false;
3540 }
3541 
3542 bool os::bind_to_processor(uint processor_id) {
3543   // Not yet implemented.
3544   return false;
3545 }
3546 
3547 ///
3548 
3549 // Suspends the target using the signal mechanism and then grabs the PC before
3550 // resuming the target. Used by the flat-profiler only
3551 ExtendedPC os::get_thread_pc(Thread* thread) {
3552   // Make sure that it is called by the watcher for the VMThread
3553   assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3554   assert(thread->is_VM_thread(), "Can only be called for VMThread");
3555 
3556   ExtendedPC epc;
3557 
3558   OSThread* osthread = thread->osthread();
3559   if (do_suspend(osthread)) {
3560     if (osthread->ucontext() != NULL) {
3561       epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
3562     } else {
3563       // NULL context is unexpected, double-check this is the VMThread
3564       guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3565     }
3566     do_resume(osthread);
3567   }
3568   // failure means pthread_kill failed for some reason - arguably this is
3569   // a fatal problem, but such problems are ignored elsewhere
3570 
3571   return epc;
3572 }
3573 
3574 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3575 {
3576   return pthread_cond_timedwait(_cond, _mutex, _abstime);
3577 }
3578 
3579 ////////////////////////////////////////////////////////////////////////////////
3580 // debug support
3581 
3582 static address same_page(address x, address y) {
3583   int page_bits = -os::vm_page_size();
3584   if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
3585     return x;
3586   else if (x > y)
3587     return (address)(intptr_t(y) | ~page_bits) + 1;
3588   else
3589     return (address)(intptr_t(y) & page_bits);
3590 }
3591 
3592 bool os::find(address addr, outputStream* st) {
3593   Dl_info dlinfo;
3594   memset(&dlinfo, 0, sizeof(dlinfo));
3595   if (dladdr(addr, &dlinfo)) {
3596     st->print(PTR_FORMAT ": ", addr);
3597     if (dlinfo.dli_sname != NULL) {
3598       st->print("%s+%#x", dlinfo.dli_sname,
3599                  addr - (intptr_t)dlinfo.dli_saddr);
3600     } else if (dlinfo.dli_fname) {
3601       st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3602     } else {
3603       st->print("<absolute address>");
3604     }
3605     if (dlinfo.dli_fname) {
3606       st->print(" in %s", dlinfo.dli_fname);
3607     }
3608     if (dlinfo.dli_fbase) {
3609       st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3610     }
3611     st->cr();
3612 
3613     if (Verbose) {
3614       // decode some bytes around the PC
3615       address begin = same_page(addr-40, addr);
3616       address end   = same_page(addr+40, addr);
3617       address       lowest = (address) dlinfo.dli_sname;
3618       if (!lowest)  lowest = (address) dlinfo.dli_fbase;
3619       if (begin < lowest)  begin = lowest;
3620       Dl_info dlinfo2;
3621       if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
3622           && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3623         end = (address) dlinfo2.dli_saddr;
3624       Disassembler::decode(begin, end, st);
3625     }
3626     return true;
3627   }
3628   return false;
3629 }
3630 
3631 ////////////////////////////////////////////////////////////////////////////////
3632 // misc
3633 
3634 // This does not do anything on Bsd. This is basically a hook for being
3635 // able to use structured exception handling (thread-local exception filters)
3636 // on, e.g., Win32.
3637 void
3638 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3639                          JavaCallArguments* args, Thread* thread) {
3640   f(value, method, args, thread);
3641 }
3642 
3643 void os::print_statistics() {
3644 }
3645 
3646 int os::message_box(const char* title, const char* message) {
3647   int i;
3648   fdStream err(defaultStream::error_fd());
3649   for (i = 0; i < 78; i++) err.print_raw("=");
3650   err.cr();
3651   err.print_raw_cr(title);
3652   for (i = 0; i < 78; i++) err.print_raw("-");
3653   err.cr();
3654   err.print_raw_cr(message);
3655   for (i = 0; i < 78; i++) err.print_raw("=");
3656   err.cr();
3657 
3658   char buf[16];
3659   // Prevent process from exiting upon "read error" without consuming all CPU
3660   while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3661 
3662   return buf[0] == 'y' || buf[0] == 'Y';
3663 }
3664 
3665 int os::stat(const char *path, struct stat *sbuf) {
3666   char pathbuf[MAX_PATH];
3667   if (strlen(path) > MAX_PATH - 1) {
3668     errno = ENAMETOOLONG;
3669     return -1;
3670   }
3671   os::native_path(strcpy(pathbuf, path));
3672   return ::stat(pathbuf, sbuf);
3673 }
3674 
3675 bool os::check_heap(bool force) {
3676   return true;
3677 }
3678 
3679 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3680   return ::vsnprintf(buf, count, format, args);
3681 }
3682 
3683 // Is a (classpath) directory empty?
3684 bool os::dir_is_empty(const char* path) {
3685   DIR *dir = NULL;
3686   struct dirent *ptr;
3687 
3688   dir = opendir(path);
3689   if (dir == NULL) return true;
3690 
3691   /* Scan the directory */
3692   bool result = true;
3693   char buf[sizeof(struct dirent) + MAX_PATH];
3694   while (result && (ptr = ::readdir(dir)) != NULL) {
3695     if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3696       result = false;
3697     }
3698   }
3699   closedir(dir);
3700   return result;
3701 }
3702 
3703 // This code originates from JDK's sysOpen and open64_w
3704 // from src/solaris/hpi/src/system_md.c
3705 
3706 #ifndef O_DELETE
3707 #define O_DELETE 0x10000
3708 #endif
3709 
3710 // Open a file. Unlink the file immediately after open returns
3711 // if the specified oflag has the O_DELETE flag set.
3712 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3713 
3714 int os::open(const char *path, int oflag, int mode) {
3715 
3716   if (strlen(path) > MAX_PATH - 1) {
3717     errno = ENAMETOOLONG;
3718     return -1;
3719   }
3720   int fd;
3721   int o_delete = (oflag & O_DELETE);
3722   oflag = oflag & ~O_DELETE;
3723 
3724   fd = ::open(path, oflag, mode);
3725   if (fd == -1) return -1;
3726 
3727   //If the open succeeded, the file might still be a directory
3728   {
3729     struct stat buf;
3730     int ret = ::fstat(fd, &buf);
3731     int st_mode = buf.st_mode;
3732 
3733     if (ret != -1) {
3734       if ((st_mode & S_IFMT) == S_IFDIR) {
3735         errno = EISDIR;
3736         ::close(fd);
3737         return -1;
3738       }
3739     } else {
3740       ::close(fd);
3741       return -1;
3742     }
3743   }
3744 
3745     /*
3746      * All file descriptors that are opened in the JVM and not
3747      * specifically destined for a subprocess should have the
3748      * close-on-exec flag set.  If we don't set it, then careless 3rd
3749      * party native code might fork and exec without closing all
3750      * appropriate file descriptors (e.g. as we do in closeDescriptors in
3751      * UNIXProcess.c), and this in turn might:
3752      *
3753      * - cause end-of-file to fail to be detected on some file
3754      *   descriptors, resulting in mysterious hangs, or
3755      *
3756      * - might cause an fopen in the subprocess to fail on a system
3757      *   suffering from bug 1085341.
3758      *
3759      * (Yes, the default setting of the close-on-exec flag is a Unix
3760      * design flaw)
3761      *
3762      * See:
3763      * 1085341: 32-bit stdio routines should support file descriptors >255
3764      * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3765      * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3766      */
3767 #ifdef FD_CLOEXEC
3768     {
3769         int flags = ::fcntl(fd, F_GETFD);
3770         if (flags != -1)
3771             ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3772     }
3773 #endif
3774 
3775   if (o_delete != 0) {
3776     ::unlink(path);
3777   }
3778   return fd;
3779 }
3780 
3781 
3782 // create binary file, rewriting existing file if required
3783 int os::create_binary_file(const char* path, bool rewrite_existing) {
3784   int oflags = O_WRONLY | O_CREAT;
3785   if (!rewrite_existing) {
3786     oflags |= O_EXCL;
3787   }
3788   return ::open(path, oflags, S_IREAD | S_IWRITE);
3789 }
3790 
3791 // return current position of file pointer
3792 jlong os::current_file_offset(int fd) {
3793   return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3794 }
3795 
3796 // move file pointer to the specified offset
3797 jlong os::seek_to_file_offset(int fd, jlong offset) {
3798   return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3799 }
3800 
3801 // This code originates from JDK's sysAvailable
3802 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3803 
3804 int os::available(int fd, jlong *bytes) {
3805   jlong cur, end;
3806   int mode;
3807   struct stat buf;
3808 
3809   if (::fstat(fd, &buf) >= 0) {
3810     mode = buf.st_mode;
3811     if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3812       /*
3813       * XXX: is the following call interruptible? If so, this might
3814       * need to go through the INTERRUPT_IO() wrapper as for other
3815       * blocking, interruptible calls in this file.
3816       */
3817       int n;
3818       if (::ioctl(fd, FIONREAD, &n) >= 0) {
3819         *bytes = n;
3820         return 1;
3821       }
3822     }
3823   }
3824   if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3825     return 0;
3826   } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3827     return 0;
3828   } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3829     return 0;
3830   }
3831   *bytes = end - cur;
3832   return 1;
3833 }
3834 
3835 int os::socket_available(int fd, jint *pbytes) {
3836    if (fd < 0)
3837      return OS_OK;
3838 
3839    int ret;
3840 
3841    RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3842 
3843    //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3844    // is expected to return 0 on failure and 1 on success to the jdk.
3845 
3846    return (ret == OS_ERR) ? 0 : 1;
3847 }
3848 
3849 // Map a block of memory.
3850 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3851                      char *addr, size_t bytes, bool read_only,
3852                      bool allow_exec) {
3853   int prot;
3854   int flags;
3855 
3856   if (read_only) {
3857     prot = PROT_READ;
3858     flags = MAP_SHARED;
3859   } else {
3860     prot = PROT_READ | PROT_WRITE;
3861     flags = MAP_PRIVATE;
3862   }
3863 
3864   if (allow_exec) {
3865     prot |= PROT_EXEC;
3866   }
3867 
3868   if (addr != NULL) {
3869     flags |= MAP_FIXED;
3870   }
3871 
3872   char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3873                                      fd, file_offset);
3874   if (mapped_address == MAP_FAILED) {
3875     return NULL;
3876   }
3877   return mapped_address;
3878 }
3879 
3880 
3881 // Remap a block of memory.
3882 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3883                        char *addr, size_t bytes, bool read_only,
3884                        bool allow_exec) {
3885   // same as map_memory() on this OS
3886   return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3887                         allow_exec);
3888 }
3889 
3890 
3891 // Unmap a block of memory.
3892 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3893   return munmap(addr, bytes) == 0;
3894 }
3895 
3896 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3897 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3898 // of a thread.
3899 //
3900 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3901 // the fast estimate available on the platform.
3902 
3903 jlong os::current_thread_cpu_time() {
3904 #ifdef __APPLE__
3905   return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3906 #endif
3907 }
3908 
3909 jlong os::thread_cpu_time(Thread* thread) {
3910 }
3911 
3912 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3913 #ifdef __APPLE__
3914   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3915 #endif
3916 }
3917 
3918 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3919 #ifdef __APPLE__
3920   struct thread_basic_info tinfo;
3921   mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3922   kern_return_t kr;
3923   thread_t mach_thread;
3924 
3925   mach_thread = thread->osthread()->thread_id();
3926   kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3927   if (kr != KERN_SUCCESS)
3928     return -1;
3929 
3930   if (user_sys_cpu_time) {
3931     jlong nanos;
3932     nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3933     nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3934     return nanos;
3935   } else {
3936     return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3937   }
3938 #endif
3939 }
3940 
3941 
3942 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3943   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3944   info_ptr->may_skip_backward = false;     // elapsed time not wall time
3945   info_ptr->may_skip_forward = false;      // elapsed time not wall time
3946   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3947 }
3948 
3949 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3950   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3951   info_ptr->may_skip_backward = false;     // elapsed time not wall time
3952   info_ptr->may_skip_forward = false;      // elapsed time not wall time
3953   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3954 }
3955 
3956 bool os::is_thread_cpu_time_supported() {
3957 #ifdef __APPLE__
3958   return true;
3959 #else
3960   return false;
3961 #endif
3962 }
3963 
3964 // System loadavg support.  Returns -1 if load average cannot be obtained.
3965 // Bsd doesn't yet have a (official) notion of processor sets,
3966 // so just return the system wide load average.
3967 int os::loadavg(double loadavg[], int nelem) {
3968   return ::getloadavg(loadavg, nelem);
3969 }
3970 
3971 void os::pause() {
3972   char filename[MAX_PATH];
3973   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3974     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3975   } else {
3976     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3977   }
3978 
3979   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3980   if (fd != -1) {
3981     struct stat buf;
3982     ::close(fd);
3983     while (::stat(filename, &buf) == 0) {
3984       (void)::poll(NULL, 0, 100);
3985     }
3986   } else {
3987     jio_fprintf(stderr,
3988       "Could not open pause file '%s', continuing immediately.\n", filename);
3989   }
3990 }
3991 
3992 
3993 // Refer to the comments in os_solaris.cpp park-unpark.
3994 //
3995 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
3996 // hang indefinitely.  For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
3997 // For specifics regarding the bug see GLIBC BUGID 261237 :
3998 //    http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
3999 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4000 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4001 // is used.  (The simple C test-case provided in the GLIBC bug report manifests the
4002 // hang).  The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4003 // and monitorenter when we're using 1-0 locking.  All those operations may result in
4004 // calls to pthread_cond_timedwait().  Using LD_ASSUME_KERNEL to use an older version
4005 // of libpthread avoids the problem, but isn't practical.
4006 //
4007 // Possible remedies:
4008 //
4009 // 1.   Establish a minimum relative wait time.  50 to 100 msecs seems to work.
4010 //      This is palliative and probabilistic, however.  If the thread is preempted
4011 //      between the call to compute_abstime() and pthread_cond_timedwait(), more
4012 //      than the minimum period may have passed, and the abstime may be stale (in the
4013 //      past) resultin in a hang.   Using this technique reduces the odds of a hang
4014 //      but the JVM is still vulnerable, particularly on heavily loaded systems.
4015 //
4016 // 2.   Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4017 //      of the usual flag-condvar-mutex idiom.  The write side of the pipe is set
4018 //      NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4019 //      reduces to poll()+read().  This works well, but consumes 2 FDs per extant
4020 //      thread.
4021 //
4022 // 3.   Embargo pthread_cond_timedwait() and implement a native "chron" thread
4023 //      that manages timeouts.  We'd emulate pthread_cond_timedwait() by enqueuing
4024 //      a timeout request to the chron thread and then blocking via pthread_cond_wait().
4025 //      This also works well.  In fact it avoids kernel-level scalability impediments
4026 //      on certain platforms that don't handle lots of active pthread_cond_timedwait()
4027 //      timers in a graceful fashion.
4028 //
4029 // 4.   When the abstime value is in the past it appears that control returns
4030 //      correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4031 //      Subsequent timedwait/wait calls may hang indefinitely.  Given that, we
4032 //      can avoid the problem by reinitializing the condvar -- by cond_destroy()
4033 //      followed by cond_init() -- after all calls to pthread_cond_timedwait().
4034 //      It may be possible to avoid reinitialization by checking the return
4035 //      value from pthread_cond_timedwait().  In addition to reinitializing the
4036 //      condvar we must establish the invariant that cond_signal() is only called
4037 //      within critical sections protected by the adjunct mutex.  This prevents
4038 //      cond_signal() from "seeing" a condvar that's in the midst of being
4039 //      reinitialized or that is corrupt.  Sadly, this invariant obviates the
4040 //      desirable signal-after-unlock optimization that avoids futile context switching.
4041 //
4042 //      I'm also concerned that some versions of NTPL might allocate an auxilliary
4043 //      structure when a condvar is used or initialized.  cond_destroy()  would
4044 //      release the helper structure.  Our reinitialize-after-timedwait fix
4045 //      put excessive stress on malloc/free and locks protecting the c-heap.
4046 //
4047 // We currently use (4).  See the WorkAroundNTPLTimedWaitHang flag.
4048 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4049 // and only enabling the work-around for vulnerable environments.
4050 
4051 // utility to compute the abstime argument to timedwait:
4052 // millis is the relative timeout time
4053 // abstime will be the absolute timeout time
4054 // TODO: replace compute_abstime() with unpackTime()
4055 
4056 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4057   if (millis < 0)  millis = 0;
4058   struct timeval now;
4059   int status = gettimeofday(&now, NULL);
4060   assert(status == 0, "gettimeofday");
4061   jlong seconds = millis / 1000;
4062   millis %= 1000;
4063   if (seconds > 50000000) { // see man cond_timedwait(3T)
4064     seconds = 50000000;
4065   }
4066   abstime->tv_sec = now.tv_sec  + seconds;
4067   long       usec = now.tv_usec + millis * 1000;
4068   if (usec >= 1000000) {
4069     abstime->tv_sec += 1;
4070     usec -= 1000000;
4071   }
4072   abstime->tv_nsec = usec * 1000;
4073   return abstime;
4074 }
4075 
4076 
4077 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4078 // Conceptually TryPark() should be equivalent to park(0).
4079 
4080 int os::PlatformEvent::TryPark() {
4081   for (;;) {
4082     const int v = _Event ;
4083     guarantee ((v == 0) || (v == 1), "invariant") ;
4084     if (Atomic::cmpxchg (0, &_Event, v) == v) return v  ;
4085   }
4086 }
4087 
4088 void os::PlatformEvent::park() {       // AKA "down()"
4089   // Invariant: Only the thread associated with the Event/PlatformEvent
4090   // may call park().
4091   // TODO: assert that _Assoc != NULL or _Assoc == Self
4092   int v ;
4093   for (;;) {
4094       v = _Event ;
4095       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4096   }
4097   guarantee (v >= 0, "invariant") ;
4098   if (v == 0) {
4099      // Do this the hard way by blocking ...
4100      int status = pthread_mutex_lock(_mutex);
4101      assert_status(status == 0, status, "mutex_lock");
4102      guarantee (_nParked == 0, "invariant") ;
4103      ++ _nParked ;
4104      while (_Event < 0) {
4105         status = pthread_cond_wait(_cond, _mutex);
4106         // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4107         // Treat this the same as if the wait was interrupted
4108         if (status == ETIMEDOUT) { status = EINTR; }
4109         assert_status(status == 0 || status == EINTR, status, "cond_wait");
4110      }
4111      -- _nParked ;
4112 
4113     _Event = 0 ;
4114      status = pthread_mutex_unlock(_mutex);
4115      assert_status(status == 0, status, "mutex_unlock");
4116     // Paranoia to ensure our locked and lock-free paths interact
4117     // correctly with each other.
4118     OrderAccess::fence();
4119   }
4120   guarantee (_Event >= 0, "invariant") ;
4121 }
4122 
4123 int os::PlatformEvent::park(jlong millis) {
4124   guarantee (_nParked == 0, "invariant") ;
4125 
4126   int v ;
4127   for (;;) {
4128       v = _Event ;
4129       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4130   }
4131   guarantee (v >= 0, "invariant") ;
4132   if (v != 0) return OS_OK ;
4133 
4134   // We do this the hard way, by blocking the thread.
4135   // Consider enforcing a minimum timeout value.
4136   struct timespec abst;
4137   compute_abstime(&abst, millis);
4138 
4139   int ret = OS_TIMEOUT;
4140   int status = pthread_mutex_lock(_mutex);
4141   assert_status(status == 0, status, "mutex_lock");
4142   guarantee (_nParked == 0, "invariant") ;
4143   ++_nParked ;
4144 
4145   // Object.wait(timo) will return because of
4146   // (a) notification
4147   // (b) timeout
4148   // (c) thread.interrupt
4149   //
4150   // Thread.interrupt and object.notify{All} both call Event::set.
4151   // That is, we treat thread.interrupt as a special case of notification.
4152   // The underlying Solaris implementation, cond_timedwait, admits
4153   // spurious/premature wakeups, but the JLS/JVM spec prevents the
4154   // JVM from making those visible to Java code.  As such, we must
4155   // filter out spurious wakeups.  We assume all ETIME returns are valid.
4156   //
4157   // TODO: properly differentiate simultaneous notify+interrupt.
4158   // In that case, we should propagate the notify to another waiter.
4159 
4160   while (_Event < 0) {
4161     status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4162     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4163       pthread_cond_destroy (_cond);
4164       pthread_cond_init (_cond, NULL) ;
4165     }
4166     assert_status(status == 0 || status == EINTR ||
4167                   status == ETIMEDOUT,
4168                   status, "cond_timedwait");
4169     if (!FilterSpuriousWakeups) break ;                 // previous semantics
4170     if (status == ETIMEDOUT) break ;
4171     // We consume and ignore EINTR and spurious wakeups.
4172   }
4173   --_nParked ;
4174   if (_Event >= 0) {
4175      ret = OS_OK;
4176   }
4177   _Event = 0 ;
4178   status = pthread_mutex_unlock(_mutex);
4179   assert_status(status == 0, status, "mutex_unlock");
4180   assert (_nParked == 0, "invariant") ;
4181   // Paranoia to ensure our locked and lock-free paths interact
4182   // correctly with each other.
4183   OrderAccess::fence();
4184   return ret;
4185 }
4186 
4187 void os::PlatformEvent::unpark() {
4188   // Transitions for _Event:
4189   //    0 :=> 1
4190   //    1 :=> 1
4191   //   -1 :=> either 0 or 1; must signal target thread
4192   //          That is, we can safely transition _Event from -1 to either
4193   //          0 or 1. Forcing 1 is slightly more efficient for back-to-back
4194   //          unpark() calls.
4195   // See also: "Semaphores in Plan 9" by Mullender & Cox
4196   //
4197   // Note: Forcing a transition from "-1" to "1" on an unpark() means
4198   // that it will take two back-to-back park() calls for the owning
4199   // thread to block. This has the benefit of forcing a spurious return
4200   // from the first park() call after an unpark() call which will help
4201   // shake out uses of park() and unpark() without condition variables.
4202 
4203   if (Atomic::xchg(1, &_Event) >= 0) return;
4204 
4205   // Wait for the thread associated with the event to vacate
4206   int status = pthread_mutex_lock(_mutex);
4207   assert_status(status == 0, status, "mutex_lock");
4208   int AnyWaiters = _nParked;
4209   assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4210   if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4211     AnyWaiters = 0;
4212     pthread_cond_signal(_cond);
4213   }
4214   status = pthread_mutex_unlock(_mutex);
4215   assert_status(status == 0, status, "mutex_unlock");
4216   if (AnyWaiters != 0) {
4217     status = pthread_cond_signal(_cond);
4218     assert_status(status == 0, status, "cond_signal");
4219   }
4220 
4221   // Note that we signal() _after dropping the lock for "immortal" Events.
4222   // This is safe and avoids a common class of  futile wakeups.  In rare
4223   // circumstances this can cause a thread to return prematurely from
4224   // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4225   // simply re-test the condition and re-park itself.
4226 }
4227 
4228 
4229 // JSR166
4230 // -------------------------------------------------------
4231 
4232 /*
4233  * The solaris and bsd implementations of park/unpark are fairly
4234  * conservative for now, but can be improved. They currently use a
4235  * mutex/condvar pair, plus a a count.
4236  * Park decrements count if > 0, else does a condvar wait.  Unpark
4237  * sets count to 1 and signals condvar.  Only one thread ever waits
4238  * on the condvar. Contention seen when trying to park implies that someone
4239  * is unparking you, so don't wait. And spurious returns are fine, so there
4240  * is no need to track notifications.
4241  */
4242 
4243 #define MAX_SECS 100000000
4244 /*
4245  * This code is common to bsd and solaris and will be moved to a
4246  * common place in dolphin.
4247  *
4248  * The passed in time value is either a relative time in nanoseconds
4249  * or an absolute time in milliseconds. Either way it has to be unpacked
4250  * into suitable seconds and nanoseconds components and stored in the
4251  * given timespec structure.
4252  * Given time is a 64-bit value and the time_t used in the timespec is only
4253  * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4254  * overflow if times way in the future are given. Further on Solaris versions
4255  * prior to 10 there is a restriction (see cond_timedwait) that the specified
4256  * number of seconds, in abstime, is less than current_time  + 100,000,000.
4257  * As it will be 28 years before "now + 100000000" will overflow we can
4258  * ignore overflow and just impose a hard-limit on seconds using the value
4259  * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4260  * years from "now".
4261  */
4262 
4263 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4264   assert (time > 0, "convertTime");
4265 
4266   struct timeval now;
4267   int status = gettimeofday(&now, NULL);
4268   assert(status == 0, "gettimeofday");
4269 
4270   time_t max_secs = now.tv_sec + MAX_SECS;
4271 
4272   if (isAbsolute) {
4273     jlong secs = time / 1000;
4274     if (secs > max_secs) {
4275       absTime->tv_sec = max_secs;
4276     }
4277     else {
4278       absTime->tv_sec = secs;
4279     }
4280     absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4281   }
4282   else {
4283     jlong secs = time / NANOSECS_PER_SEC;
4284     if (secs >= MAX_SECS) {
4285       absTime->tv_sec = max_secs;
4286       absTime->tv_nsec = 0;
4287     }
4288     else {
4289       absTime->tv_sec = now.tv_sec + secs;
4290       absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4291       if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4292         absTime->tv_nsec -= NANOSECS_PER_SEC;
4293         ++absTime->tv_sec; // note: this must be <= max_secs
4294       }
4295     }
4296   }
4297   assert(absTime->tv_sec >= 0, "tv_sec < 0");
4298   assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4299   assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4300   assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4301 }
4302 
4303 void Parker::park(bool isAbsolute, jlong time) {
4304   // Ideally we'd do something useful while spinning, such
4305   // as calling unpackTime().
4306 
4307   // Optional fast-path check:
4308   // Return immediately if a permit is available.
4309   // We depend on Atomic::xchg() having full barrier semantics
4310   // since we are doing a lock-free update to _counter.
4311   if (Atomic::xchg(0, &_counter) > 0) return;
4312 
4313   Thread* thread = Thread::current();
4314   assert(thread->is_Java_thread(), "Must be JavaThread");
4315   JavaThread *jt = (JavaThread *)thread;
4316 
4317   // Optional optimization -- avoid state transitions if there's an interrupt pending.
4318   // Check interrupt before trying to wait
4319   if (Thread::is_interrupted(thread, false)) {
4320     return;
4321   }
4322 
4323   // Next, demultiplex/decode time arguments
4324   struct timespec absTime;
4325   if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4326     return;
4327   }
4328   if (time > 0) {
4329     unpackTime(&absTime, isAbsolute, time);
4330   }
4331 
4332 
4333   // Enter safepoint region
4334   // Beware of deadlocks such as 6317397.
4335   // The per-thread Parker:: mutex is a classic leaf-lock.
4336   // In particular a thread must never block on the Threads_lock while
4337   // holding the Parker:: mutex.  If safepoints are pending both the
4338   // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4339   ThreadBlockInVM tbivm(jt);
4340 
4341   // Don't wait if cannot get lock since interference arises from
4342   // unblocking.  Also. check interrupt before trying wait
4343   if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4344     return;
4345   }
4346 
4347   int status ;
4348   if (_counter > 0)  { // no wait needed
4349     _counter = 0;
4350     status = pthread_mutex_unlock(_mutex);
4351     assert (status == 0, "invariant") ;
4352     // Paranoia to ensure our locked and lock-free paths interact
4353     // correctly with each other and Java-level accesses.
4354     OrderAccess::fence();
4355     return;
4356   }
4357 
4358 #ifdef ASSERT
4359   // Don't catch signals while blocked; let the running threads have the signals.
4360   // (This allows a debugger to break into the running thread.)
4361   sigset_t oldsigs;
4362   sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4363   pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4364 #endif
4365 
4366   OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4367   jt->set_suspend_equivalent();
4368   // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4369 
4370   if (time == 0) {
4371     status = pthread_cond_wait (_cond, _mutex) ;
4372   } else {
4373     status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4374     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4375       pthread_cond_destroy (_cond) ;
4376       pthread_cond_init    (_cond, NULL);
4377     }
4378   }
4379   assert_status(status == 0 || status == EINTR ||
4380                 status == ETIMEDOUT,
4381                 status, "cond_timedwait");
4382 
4383 #ifdef ASSERT
4384   pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4385 #endif
4386 
4387   _counter = 0 ;
4388   status = pthread_mutex_unlock(_mutex) ;
4389   assert_status(status == 0, status, "invariant") ;
4390   // Paranoia to ensure our locked and lock-free paths interact
4391   // correctly with each other and Java-level accesses.
4392   OrderAccess::fence();
4393 
4394   // If externally suspended while waiting, re-suspend
4395   if (jt->handle_special_suspend_equivalent_condition()) {
4396     jt->java_suspend_self();
4397   }
4398 }
4399 
4400 void Parker::unpark() {
4401   int s, status ;
4402   status = pthread_mutex_lock(_mutex);
4403   assert (status == 0, "invariant") ;
4404   s = _counter;
4405   _counter = 1;
4406   if (s < 1) {
4407      if (WorkAroundNPTLTimedWaitHang) {
4408         status = pthread_cond_signal (_cond) ;
4409         assert (status == 0, "invariant") ;
4410         status = pthread_mutex_unlock(_mutex);
4411         assert (status == 0, "invariant") ;
4412      } else {
4413         status = pthread_mutex_unlock(_mutex);
4414         assert (status == 0, "invariant") ;
4415         status = pthread_cond_signal (_cond) ;
4416         assert (status == 0, "invariant") ;
4417      }
4418   } else {
4419     pthread_mutex_unlock(_mutex);
4420     assert (status == 0, "invariant") ;
4421   }
4422 }
4423 
4424 
4425 /* Darwin has no "environ" in a dynamic library. */
4426 #ifdef __APPLE__
4427 #include <crt_externs.h>
4428 #define environ (*_NSGetEnviron())
4429 #else
4430 extern char** environ;
4431 #endif
4432 
4433 // Run the specified command in a separate process. Return its exit value,
4434 // or -1 on failure (e.g. can't fork a new process).
4435 // Unlike system(), this function can be called from signal handler. It
4436 // doesn't block SIGINT et al.
4437 int os::fork_and_exec(char* cmd) {
4438   const char * argv[4] = {"sh", "-c", cmd, NULL};
4439 
4440   // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4441   // pthread_atfork handlers and reset pthread library. All we need is a
4442   // separate process to execve. Make a direct syscall to fork process.
4443   // On IA64 there's no fork syscall, we have to use fork() and hope for
4444   // the best...
4445   pid_t pid = fork();
4446 
4447   if (pid < 0) {
4448     // fork failed
4449     return -1;
4450 
4451   } else if (pid == 0) {
4452     // child process
4453 
4454     // execve() in BsdThreads will call pthread_kill_other_threads_np()
4455     // first to kill every thread on the thread list. Because this list is
4456     // not reset by fork() (see notes above), execve() will instead kill
4457     // every thread in the parent process. We know this is the only thread
4458     // in the new process, so make a system call directly.
4459     // IA64 should use normal execve() from glibc to match the glibc fork()
4460     // above.
4461     execve("/bin/sh", (char* const*)argv, environ);
4462 
4463     // execve failed
4464     _exit(-1);
4465 
4466   } else  {
4467     // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4468     // care about the actual exit code, for now.
4469 
4470     int status;
4471 
4472     // Wait for the child process to exit.  This returns immediately if
4473     // the child has already exited. */
4474     while (waitpid(pid, &status, 0) < 0) {
4475         switch (errno) {
4476         case ECHILD: return 0;
4477         case EINTR: break;
4478         default: return -1;
4479         }
4480     }
4481 
4482     if (WIFEXITED(status)) {
4483        // The child exited normally; get its exit code.
4484        return WEXITSTATUS(status);
4485     } else if (WIFSIGNALED(status)) {
4486        // The child exited because of a signal
4487        // The best value to return is 0x80 + signal number,
4488        // because that is what all Unix shells do, and because
4489        // it allows callers to distinguish between process exit and
4490        // process death by signal.
4491        return 0x80 + WTERMSIG(status);
4492     } else {
4493        // Unknown exit code; pass it through
4494        return status;
4495     }
4496   }
4497 }
4498 
4499 // is_headless_jre()
4500 //
4501 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4502 // in order to report if we are running in a headless jre
4503 //
4504 // Since JDK8 xawt/libmawt.so was moved into the same directory
4505 // as libawt.so, and renamed libawt_xawt.so
4506 //
4507 bool os::is_headless_jre() {
4508     struct stat statbuf;
4509     char buf[MAXPATHLEN];
4510     char libmawtpath[MAXPATHLEN];
4511     const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
4512     const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4513     char *p;
4514 
4515     // Get path to libjvm.so
4516     os::jvm_path(buf, sizeof(buf));
4517 
4518     // Get rid of libjvm.so
4519     p = strrchr(buf, '/');
4520     if (p == NULL) return false;
4521     else *p = '\0';
4522 
4523     // Get rid of client or server
4524     p = strrchr(buf, '/');
4525     if (p == NULL) return false;
4526     else *p = '\0';
4527 
4528     // check xawt/libmawt.so
4529     strcpy(libmawtpath, buf);
4530     strcat(libmawtpath, xawtstr);
4531     if (::stat(libmawtpath, &statbuf) == 0) return false;
4532 
4533     // check libawt_xawt.so
4534     strcpy(libmawtpath, buf);
4535     strcat(libmawtpath, new_xawtstr);
4536     if (::stat(libmawtpath, &statbuf) == 0) return false;
4537 
4538     return true;
4539 }
4540 
4541 // Get the default path to the core file
4542 // Returns the length of the string
4543 int os::get_core_path(char* buffer, size_t bufferSize) {
4544   int n = jio_snprintf(buffer, bufferSize, "/cores");
4545 
4546   // Truncate if theoretical string was longer than bufferSize
4547   n = MIN2(n, (int)bufferSize);
4548 
4549   return n;
4550 }