os_bsd.cpp revision 3957:7d42f3b08300
1/*
2 * Copyright (c) 1999, 2012, 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
126julong os::Bsd::_physical_memory = 0;
127
128
129int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
130pthread_t os::Bsd::_main_thread;
131int os::Bsd::_page_size = -1;
132
133static jlong initial_time_count=0;
134
135static int clock_tics_per_sec = 100;
136
137// For diagnostics to print a message once. see run_periodic_checks
138static sigset_t check_signal_done;
139static bool check_signals = true;
140
141static 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 */
146static int SR_signum = SIGUSR2;
147sigset_t SR_sigset;
148
149
150////////////////////////////////////////////////////////////////////////////////
151// utility functions
152
153static int SR_initialize();
154static int SR_finalize();
155
156julong os::available_memory() {
157  return Bsd::available_memory();
158}
159
160julong os::Bsd::available_memory() {
161  // XXXBSD: this is just a stopgap implementation
162  return physical_memory() >> 2;
163}
164
165julong os::physical_memory() {
166  return Bsd::physical_memory();
167}
168
169julong 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
186bool 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
199bool 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)
213static char cpu_arch[] = ZERO_LIBARCH;
214#elif defined(IA64)
215static char cpu_arch[] = "ia64";
216#elif defined(IA32)
217static char cpu_arch[] = "i386";
218#elif defined(AMD64)
219static char cpu_arch[] = "amd64";
220#elif defined(ARM)
221static char cpu_arch[] = "arm";
222#elif defined(PPC)
223static char cpu_arch[] = "ppc";
224#elif defined(SPARC)
225#  ifdef _LP64
226static char cpu_arch[] = "sparcv9";
227#  else
228static 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
242void os::Bsd::initialize_system_info() {
243  int mib[2];
244  size_t len;
245  int cpu_val;
246  u_long 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       set_processor_count(cpu_val);
254  }
255  else {
256       set_processor_count(1);   // fallback
257  }
258
259  /* get physical memory via hw.usermem sysctl (hw.usermem is used
260   * instead of hw.physmem because we need size of allocatable memory
261   */
262  mib[0] = CTL_HW;
263  mib[1] = HW_USERMEM;
264  len = sizeof(mem_val);
265  if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1)
266       _physical_memory = mem_val;
267  else
268       _physical_memory = 256*1024*1024;       // fallback (XXXBSD?)
269
270#ifdef __OpenBSD__
271  {
272       // limit _physical_memory memory view on OpenBSD since
273       // datasize rlimit restricts us anyway.
274       struct rlimit limits;
275       getrlimit(RLIMIT_DATA, &limits);
276       _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
277  }
278#endif
279}
280
281#ifdef __APPLE__
282static const char *get_home() {
283  const char *home_dir = ::getenv("HOME");
284  if ((home_dir == NULL) || (*home_dir == '\0')) {
285    struct passwd *passwd_info = getpwuid(geteuid());
286    if (passwd_info != NULL) {
287      home_dir = passwd_info->pw_dir;
288    }
289  }
290
291  return home_dir;
292}
293#endif
294
295void os::init_system_properties_values() {
296//  char arch[12];
297//  sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
298
299  // The next steps are taken in the product version:
300  //
301  // Obtain the JAVA_HOME value from the location of libjvm.so.
302  // This library should be located at:
303  // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
304  //
305  // If "/jre/lib/" appears at the right place in the path, then we
306  // assume libjvm.so is installed in a JDK and we use this path.
307  //
308  // Otherwise exit with message: "Could not create the Java virtual machine."
309  //
310  // The following extra steps are taken in the debugging version:
311  //
312  // If "/jre/lib/" does NOT appear at the right place in the path
313  // instead of exit check for $JAVA_HOME environment variable.
314  //
315  // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
316  // then we append a fake suffix "hotspot/libjvm.so" to this path so
317  // it looks like libjvm.so is installed there
318  // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
319  //
320  // Otherwise exit.
321  //
322  // Important note: if the location of libjvm.so changes this
323  // code needs to be changed accordingly.
324
325  // The next few definitions allow the code to be verbatim:
326#define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
327#define getenv(n) ::getenv(n)
328
329/*
330 * See ld(1):
331 *      The linker uses the following search paths to locate required
332 *      shared libraries:
333 *        1: ...
334 *        ...
335 *        7: The default directories, normally /lib and /usr/lib.
336 */
337#ifndef DEFAULT_LIBPATH
338#define DEFAULT_LIBPATH "/lib:/usr/lib"
339#endif
340
341#define EXTENSIONS_DIR  "/lib/ext"
342#define ENDORSED_DIR    "/lib/endorsed"
343#define REG_DIR         "/usr/java/packages"
344
345#ifdef __APPLE__
346#define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
347#define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
348        const char *user_home_dir = get_home();
349        // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
350        int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
351            sizeof(SYS_EXTENSIONS_DIRS);
352#endif
353
354  {
355    /* sysclasspath, java_home, dll_dir */
356    {
357        char *home_path;
358        char *dll_path;
359        char *pslash;
360        char buf[MAXPATHLEN];
361        os::jvm_path(buf, sizeof(buf));
362
363        // Found the full path to libjvm.so.
364        // Now cut the path to <java_home>/jre if we can.
365        *(strrchr(buf, '/')) = '\0';  /* get rid of /libjvm.so */
366        pslash = strrchr(buf, '/');
367        if (pslash != NULL)
368            *pslash = '\0';           /* get rid of /{client|server|hotspot} */
369        dll_path = malloc(strlen(buf) + 1);
370        if (dll_path == NULL)
371            return;
372        strcpy(dll_path, buf);
373        Arguments::set_dll_dir(dll_path);
374
375        if (pslash != NULL) {
376            pslash = strrchr(buf, '/');
377            if (pslash != NULL) {
378                *pslash = '\0';       /* get rid of /<arch> (/lib on macosx) */
379#ifndef __APPLE__
380                pslash = strrchr(buf, '/');
381                if (pslash != NULL)
382                    *pslash = '\0';   /* get rid of /lib */
383#endif
384            }
385        }
386
387        home_path = malloc(strlen(buf) + 1);
388        if (home_path == NULL)
389            return;
390        strcpy(home_path, buf);
391        Arguments::set_java_home(home_path);
392
393        if (!set_boot_path('/', ':'))
394            return;
395    }
396
397    /*
398     * Where to look for native libraries
399     *
400     * Note: Due to a legacy implementation, most of the library path
401     * is set in the launcher.  This was to accomodate linking restrictions
402     * on legacy Bsd implementations (which are no longer supported).
403     * Eventually, all the library path setting will be done here.
404     *
405     * However, to prevent the proliferation of improperly built native
406     * libraries, the new path component /usr/java/packages is added here.
407     * Eventually, all the library path setting will be done here.
408     */
409    {
410        char *ld_library_path;
411
412        /*
413         * Construct the invariant part of ld_library_path. Note that the
414         * space for the colon and the trailing null are provided by the
415         * nulls included by the sizeof operator (so actually we allocate
416         * a byte more than necessary).
417         */
418#ifdef __APPLE__
419        ld_library_path = (char *) malloc(system_ext_size);
420        sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
421#else
422        ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
423            strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
424        sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
425#endif
426
427        /*
428         * Get the user setting of LD_LIBRARY_PATH, and prepended it.  It
429         * should always exist (until the legacy problem cited above is
430         * addressed).
431         */
432#ifdef __APPLE__
433        // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
434        char *l = getenv("JAVA_LIBRARY_PATH");
435        if (l != NULL) {
436            char *t = ld_library_path;
437            /* That's +1 for the colon and +1 for the trailing '\0' */
438            ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
439            sprintf(ld_library_path, "%s:%s", l, t);
440            free(t);
441        }
442
443        char *v = getenv("DYLD_LIBRARY_PATH");
444#else
445        char *v = getenv("LD_LIBRARY_PATH");
446#endif
447        if (v != NULL) {
448            char *t = ld_library_path;
449            /* That's +1 for the colon and +1 for the trailing '\0' */
450            ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
451            sprintf(ld_library_path, "%s:%s", v, t);
452            free(t);
453        }
454
455#ifdef __APPLE__
456        // Apple's Java6 has "." at the beginning of java.library.path.
457        // OpenJDK on Windows has "." at the end of java.library.path.
458        // OpenJDK on Linux and Solaris don't have "." in java.library.path
459        // at all. To ease the transition from Apple's Java6 to OpenJDK7,
460        // "." is appended to the end of java.library.path. Yes, this
461        // could cause a change in behavior, but Apple's Java6 behavior
462        // can be achieved by putting "." at the beginning of the
463        // JAVA_LIBRARY_PATH environment variable.
464        {
465            char *t = ld_library_path;
466            // that's +3 for appending ":." and the trailing '\0'
467            ld_library_path = (char *) malloc(strlen(t) + 3);
468            sprintf(ld_library_path, "%s:%s", t, ".");
469            free(t);
470        }
471#endif
472
473        Arguments::set_library_path(ld_library_path);
474    }
475
476    /*
477     * Extensions directories.
478     *
479     * Note that the space for the colon and the trailing null are provided
480     * by the nulls included by the sizeof operator (so actually one byte more
481     * than necessary is allocated).
482     */
483    {
484#ifdef __APPLE__
485        char *buf = malloc(strlen(Arguments::get_java_home()) +
486            sizeof(EXTENSIONS_DIR) + system_ext_size);
487        sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
488            SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
489#else
490        char *buf = malloc(strlen(Arguments::get_java_home()) +
491            sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
492        sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
493            Arguments::get_java_home());
494#endif
495
496        Arguments::set_ext_dirs(buf);
497    }
498
499    /* Endorsed standards default directory. */
500    {
501        char * buf;
502        buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
503        sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
504        Arguments::set_endorsed_dirs(buf);
505    }
506  }
507
508#ifdef __APPLE__
509#undef SYS_EXTENSIONS_DIR
510#endif
511#undef malloc
512#undef getenv
513#undef EXTENSIONS_DIR
514#undef ENDORSED_DIR
515
516  // Done
517  return;
518}
519
520////////////////////////////////////////////////////////////////////////////////
521// breakpoint support
522
523void os::breakpoint() {
524  BREAKPOINT;
525}
526
527extern "C" void breakpoint() {
528  // use debugger to set breakpoint here
529}
530
531////////////////////////////////////////////////////////////////////////////////
532// signal support
533
534debug_only(static bool signal_sets_initialized = false);
535static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
536
537bool os::Bsd::is_sig_ignored(int sig) {
538      struct sigaction oact;
539      sigaction(sig, (struct sigaction*)NULL, &oact);
540      void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
541                                     : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
542      if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
543           return true;
544      else
545           return false;
546}
547
548void os::Bsd::signal_sets_init() {
549  // Should also have an assertion stating we are still single-threaded.
550  assert(!signal_sets_initialized, "Already initialized");
551  // Fill in signals that are necessarily unblocked for all threads in
552  // the VM. Currently, we unblock the following signals:
553  // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
554  //                         by -Xrs (=ReduceSignalUsage));
555  // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
556  // other threads. The "ReduceSignalUsage" boolean tells us not to alter
557  // the dispositions or masks wrt these signals.
558  // Programs embedding the VM that want to use the above signals for their
559  // own purposes must, at this time, use the "-Xrs" option to prevent
560  // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
561  // (See bug 4345157, and other related bugs).
562  // In reality, though, unblocking these signals is really a nop, since
563  // these signals are not blocked by default.
564  sigemptyset(&unblocked_sigs);
565  sigemptyset(&allowdebug_blocked_sigs);
566  sigaddset(&unblocked_sigs, SIGILL);
567  sigaddset(&unblocked_sigs, SIGSEGV);
568  sigaddset(&unblocked_sigs, SIGBUS);
569  sigaddset(&unblocked_sigs, SIGFPE);
570  sigaddset(&unblocked_sigs, SR_signum);
571
572  if (!ReduceSignalUsage) {
573   if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
574      sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
575      sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
576   }
577   if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
578      sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
579      sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
580   }
581   if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
582      sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
583      sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
584   }
585  }
586  // Fill in signals that are blocked by all but the VM thread.
587  sigemptyset(&vm_sigs);
588  if (!ReduceSignalUsage)
589    sigaddset(&vm_sigs, BREAK_SIGNAL);
590  debug_only(signal_sets_initialized = true);
591
592}
593
594// These are signals that are unblocked while a thread is running Java.
595// (For some reason, they get blocked by default.)
596sigset_t* os::Bsd::unblocked_signals() {
597  assert(signal_sets_initialized, "Not initialized");
598  return &unblocked_sigs;
599}
600
601// These are the signals that are blocked while a (non-VM) thread is
602// running Java. Only the VM thread handles these signals.
603sigset_t* os::Bsd::vm_signals() {
604  assert(signal_sets_initialized, "Not initialized");
605  return &vm_sigs;
606}
607
608// These are signals that are blocked during cond_wait to allow debugger in
609sigset_t* os::Bsd::allowdebug_blocked_signals() {
610  assert(signal_sets_initialized, "Not initialized");
611  return &allowdebug_blocked_sigs;
612}
613
614void os::Bsd::hotspot_sigmask(Thread* thread) {
615
616  //Save caller's signal mask before setting VM signal mask
617  sigset_t caller_sigmask;
618  pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
619
620  OSThread* osthread = thread->osthread();
621  osthread->set_caller_sigmask(caller_sigmask);
622
623  pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
624
625  if (!ReduceSignalUsage) {
626    if (thread->is_VM_thread()) {
627      // Only the VM thread handles BREAK_SIGNAL ...
628      pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
629    } else {
630      // ... all other threads block BREAK_SIGNAL
631      pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
632    }
633  }
634}
635
636
637//////////////////////////////////////////////////////////////////////////////
638// create new thread
639
640static address highest_vm_reserved_address();
641
642// check if it's safe to start a new thread
643static bool _thread_safety_check(Thread* thread) {
644  return true;
645}
646
647#ifdef __APPLE__
648// library handle for calling objc_registerThreadWithCollector()
649// without static linking to the libobjc library
650#define OBJC_LIB "/usr/lib/libobjc.dylib"
651#define OBJC_GCREGISTER "objc_registerThreadWithCollector"
652typedef void (*objc_registerThreadWithCollector_t)();
653extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
654objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
655#endif
656
657// Thread start routine for all newly created threads
658static void *java_start(Thread *thread) {
659  // Try to randomize the cache line index of hot stack frames.
660  // This helps when threads of the same stack traces evict each other's
661  // cache lines. The threads can be either from the same JVM instance, or
662  // from different JVM instances. The benefit is especially true for
663  // processors with hyperthreading technology.
664  static int counter = 0;
665  int pid = os::current_process_id();
666  alloca(((pid ^ counter++) & 7) * 128);
667
668  ThreadLocalStorage::set_thread(thread);
669
670  OSThread* osthread = thread->osthread();
671  Monitor* sync = osthread->startThread_lock();
672
673  // non floating stack BsdThreads needs extra check, see above
674  if (!_thread_safety_check(thread)) {
675    // notify parent thread
676    MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
677    osthread->set_state(ZOMBIE);
678    sync->notify_all();
679    return NULL;
680  }
681
682#ifdef __APPLE__
683  // thread_id is mach thread on macos
684  osthread->set_thread_id(::mach_thread_self());
685#else
686  // thread_id is pthread_id on BSD
687  osthread->set_thread_id(::pthread_self());
688#endif
689  // initialize signal mask for this thread
690  os::Bsd::hotspot_sigmask(thread);
691
692  // initialize floating point control register
693  os::Bsd::init_thread_fpu_state();
694
695#ifdef __APPLE__
696  // register thread with objc gc
697  if (objc_registerThreadWithCollectorFunction != NULL) {
698    objc_registerThreadWithCollectorFunction();
699  }
700#endif
701
702  // handshaking with parent thread
703  {
704    MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
705
706    // notify parent thread
707    osthread->set_state(INITIALIZED);
708    sync->notify_all();
709
710    // wait until os::start_thread()
711    while (osthread->get_state() == INITIALIZED) {
712      sync->wait(Mutex::_no_safepoint_check_flag);
713    }
714  }
715
716  // call one more level start routine
717  thread->run();
718
719  return 0;
720}
721
722bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
723  assert(thread->osthread() == NULL, "caller responsible");
724
725  // Allocate the OSThread object
726  OSThread* osthread = new OSThread(NULL, NULL);
727  if (osthread == NULL) {
728    return false;
729  }
730
731  // set the correct thread state
732  osthread->set_thread_type(thr_type);
733
734  // Initial state is ALLOCATED but not INITIALIZED
735  osthread->set_state(ALLOCATED);
736
737  thread->set_osthread(osthread);
738
739  // init thread attributes
740  pthread_attr_t attr;
741  pthread_attr_init(&attr);
742  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
743
744  // stack size
745  if (os::Bsd::supports_variable_stack_size()) {
746    // calculate stack size if it's not specified by caller
747    if (stack_size == 0) {
748      stack_size = os::Bsd::default_stack_size(thr_type);
749
750      switch (thr_type) {
751      case os::java_thread:
752        // Java threads use ThreadStackSize which default value can be
753        // changed with the flag -Xss
754        assert (JavaThread::stack_size_at_create() > 0, "this should be set");
755        stack_size = JavaThread::stack_size_at_create();
756        break;
757      case os::compiler_thread:
758        if (CompilerThreadStackSize > 0) {
759          stack_size = (size_t)(CompilerThreadStackSize * K);
760          break;
761        } // else fall through:
762          // use VMThreadStackSize if CompilerThreadStackSize is not defined
763      case os::vm_thread:
764      case os::pgc_thread:
765      case os::cgc_thread:
766      case os::watcher_thread:
767        if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
768        break;
769      }
770    }
771
772    stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
773    pthread_attr_setstacksize(&attr, stack_size);
774  } else {
775    // let pthread_create() pick the default value.
776  }
777
778  ThreadState state;
779
780  {
781    pthread_t tid;
782    int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
783
784    pthread_attr_destroy(&attr);
785
786    if (ret != 0) {
787      if (PrintMiscellaneous && (Verbose || WizardMode)) {
788        perror("pthread_create()");
789      }
790      // Need to clean up stuff we've allocated so far
791      thread->set_osthread(NULL);
792      delete osthread;
793      return false;
794    }
795
796    // Store pthread info into the OSThread
797    osthread->set_pthread_id(tid);
798
799    // Wait until child thread is either initialized or aborted
800    {
801      Monitor* sync_with_child = osthread->startThread_lock();
802      MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
803      while ((state = osthread->get_state()) == ALLOCATED) {
804        sync_with_child->wait(Mutex::_no_safepoint_check_flag);
805      }
806    }
807
808  }
809
810  // Aborted due to thread limit being reached
811  if (state == ZOMBIE) {
812      thread->set_osthread(NULL);
813      delete osthread;
814      return false;
815  }
816
817  // The thread is returned suspended (in state INITIALIZED),
818  // and is started higher up in the call chain
819  assert(state == INITIALIZED, "race condition");
820  return true;
821}
822
823/////////////////////////////////////////////////////////////////////////////
824// attach existing thread
825
826// bootstrap the main thread
827bool os::create_main_thread(JavaThread* thread) {
828  assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
829  return create_attached_thread(thread);
830}
831
832bool os::create_attached_thread(JavaThread* thread) {
833#ifdef ASSERT
834    thread->verify_not_published();
835#endif
836
837  // Allocate the OSThread object
838  OSThread* osthread = new OSThread(NULL, NULL);
839
840  if (osthread == NULL) {
841    return false;
842  }
843
844  // Store pthread info into the OSThread
845#ifdef __APPLE__
846  osthread->set_thread_id(::mach_thread_self());
847#else
848  osthread->set_thread_id(::pthread_self());
849#endif
850  osthread->set_pthread_id(::pthread_self());
851
852  // initialize floating point control register
853  os::Bsd::init_thread_fpu_state();
854
855  // Initial thread state is RUNNABLE
856  osthread->set_state(RUNNABLE);
857
858  thread->set_osthread(osthread);
859
860  // initialize signal mask for this thread
861  // and save the caller's signal mask
862  os::Bsd::hotspot_sigmask(thread);
863
864  return true;
865}
866
867void os::pd_start_thread(Thread* thread) {
868  OSThread * osthread = thread->osthread();
869  assert(osthread->get_state() != INITIALIZED, "just checking");
870  Monitor* sync_with_child = osthread->startThread_lock();
871  MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
872  sync_with_child->notify();
873}
874
875// Free Bsd resources related to the OSThread
876void os::free_thread(OSThread* osthread) {
877  assert(osthread != NULL, "osthread not set");
878
879  if (Thread::current()->osthread() == osthread) {
880    // Restore caller's signal mask
881    sigset_t sigmask = osthread->caller_sigmask();
882    pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
883   }
884
885  delete osthread;
886}
887
888//////////////////////////////////////////////////////////////////////////////
889// thread local storage
890
891int os::allocate_thread_local_storage() {
892  pthread_key_t key;
893  int rslt = pthread_key_create(&key, NULL);
894  assert(rslt == 0, "cannot allocate thread local storage");
895  return (int)key;
896}
897
898// Note: This is currently not used by VM, as we don't destroy TLS key
899// on VM exit.
900void os::free_thread_local_storage(int index) {
901  int rslt = pthread_key_delete((pthread_key_t)index);
902  assert(rslt == 0, "invalid index");
903}
904
905void os::thread_local_storage_at_put(int index, void* value) {
906  int rslt = pthread_setspecific((pthread_key_t)index, value);
907  assert(rslt == 0, "pthread_setspecific failed");
908}
909
910extern "C" Thread* get_thread() {
911  return ThreadLocalStorage::thread();
912}
913
914
915////////////////////////////////////////////////////////////////////////////////
916// time support
917
918// Time since start-up in seconds to a fine granularity.
919// Used by VMSelfDestructTimer and the MemProfiler.
920double os::elapsedTime() {
921
922  return (double)(os::elapsed_counter()) * 0.000001;
923}
924
925jlong os::elapsed_counter() {
926  timeval time;
927  int status = gettimeofday(&time, NULL);
928  return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
929}
930
931jlong os::elapsed_frequency() {
932  return (1000 * 1000);
933}
934
935// XXX: For now, code this as if BSD does not support vtime.
936bool os::supports_vtime() { return false; }
937bool os::enable_vtime()   { return false; }
938bool os::vtime_enabled()  { return false; }
939double os::elapsedVTime() {
940  // better than nothing, but not much
941  return elapsedTime();
942}
943
944jlong os::javaTimeMillis() {
945  timeval time;
946  int status = gettimeofday(&time, NULL);
947  assert(status != -1, "bsd error");
948  return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
949}
950
951#ifndef CLOCK_MONOTONIC
952#define CLOCK_MONOTONIC (1)
953#endif
954
955#ifdef __APPLE__
956void os::Bsd::clock_init() {
957        // XXXDARWIN: Investigate replacement monotonic clock
958}
959#else
960void os::Bsd::clock_init() {
961  struct timespec res;
962  struct timespec tp;
963  if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
964      ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
965    // yes, monotonic clock is supported
966    _clock_gettime = ::clock_gettime;
967  }
968}
969#endif
970
971
972jlong os::javaTimeNanos() {
973  if (Bsd::supports_monotonic_clock()) {
974    struct timespec tp;
975    int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
976    assert(status == 0, "gettime error");
977    jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
978    return result;
979  } else {
980    timeval time;
981    int status = gettimeofday(&time, NULL);
982    assert(status != -1, "bsd error");
983    jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
984    return 1000 * usecs;
985  }
986}
987
988void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
989  if (Bsd::supports_monotonic_clock()) {
990    info_ptr->max_value = ALL_64_BITS;
991
992    // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
993    info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
994    info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
995  } else {
996    // gettimeofday - based on time in seconds since the Epoch thus does not wrap
997    info_ptr->max_value = ALL_64_BITS;
998
999    // gettimeofday is a real time clock so it skips
1000    info_ptr->may_skip_backward = true;
1001    info_ptr->may_skip_forward = true;
1002  }
1003
1004  info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
1005}
1006
1007// Return the real, user, and system times in seconds from an
1008// arbitrary fixed point in the past.
1009bool os::getTimesSecs(double* process_real_time,
1010                      double* process_user_time,
1011                      double* process_system_time) {
1012  struct tms ticks;
1013  clock_t real_ticks = times(&ticks);
1014
1015  if (real_ticks == (clock_t) (-1)) {
1016    return false;
1017  } else {
1018    double ticks_per_second = (double) clock_tics_per_sec;
1019    *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1020    *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1021    *process_real_time = ((double) real_ticks) / ticks_per_second;
1022
1023    return true;
1024  }
1025}
1026
1027
1028char * os::local_time_string(char *buf, size_t buflen) {
1029  struct tm t;
1030  time_t long_time;
1031  time(&long_time);
1032  localtime_r(&long_time, &t);
1033  jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1034               t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1035               t.tm_hour, t.tm_min, t.tm_sec);
1036  return buf;
1037}
1038
1039struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
1040  return localtime_r(clock, res);
1041}
1042
1043////////////////////////////////////////////////////////////////////////////////
1044// runtime exit support
1045
1046// Note: os::shutdown() might be called very early during initialization, or
1047// called from signal handler. Before adding something to os::shutdown(), make
1048// sure it is async-safe and can handle partially initialized VM.
1049void os::shutdown() {
1050
1051  // allow PerfMemory to attempt cleanup of any persistent resources
1052  perfMemory_exit();
1053
1054  // needs to remove object in file system
1055  AttachListener::abort();
1056
1057  // flush buffered output, finish log files
1058  ostream_abort();
1059
1060  // Check for abort hook
1061  abort_hook_t abort_hook = Arguments::abort_hook();
1062  if (abort_hook != NULL) {
1063    abort_hook();
1064  }
1065
1066}
1067
1068// Note: os::abort() might be called very early during initialization, or
1069// called from signal handler. Before adding something to os::abort(), make
1070// sure it is async-safe and can handle partially initialized VM.
1071void os::abort(bool dump_core) {
1072  os::shutdown();
1073  if (dump_core) {
1074#ifndef PRODUCT
1075    fdStream out(defaultStream::output_fd());
1076    out.print_raw("Current thread is ");
1077    char buf[16];
1078    jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1079    out.print_raw_cr(buf);
1080    out.print_raw_cr("Dumping core ...");
1081#endif
1082    ::abort(); // dump core
1083  }
1084
1085  ::exit(1);
1086}
1087
1088// Die immediately, no exit hook, no abort hook, no cleanup.
1089void os::die() {
1090  // _exit() on BsdThreads only kills current thread
1091  ::abort();
1092}
1093
1094// unused on bsd for now.
1095void os::set_error_file(const char *logfile) {}
1096
1097
1098// This method is a copy of JDK's sysGetLastErrorString
1099// from src/solaris/hpi/src/system_md.c
1100
1101size_t os::lasterror(char *buf, size_t len) {
1102
1103  if (errno == 0)  return 0;
1104
1105  const char *s = ::strerror(errno);
1106  size_t n = ::strlen(s);
1107  if (n >= len) {
1108    n = len - 1;
1109  }
1110  ::strncpy(buf, s, n);
1111  buf[n] = '\0';
1112  return n;
1113}
1114
1115intx os::current_thread_id() {
1116#ifdef __APPLE__
1117  return (intx)::mach_thread_self();
1118#else
1119  return (intx)::pthread_self();
1120#endif
1121}
1122int os::current_process_id() {
1123
1124  // Under the old bsd thread library, bsd gives each thread
1125  // its own process id. Because of this each thread will return
1126  // a different pid if this method were to return the result
1127  // of getpid(2). Bsd provides no api that returns the pid
1128  // of the launcher thread for the vm. This implementation
1129  // returns a unique pid, the pid of the launcher thread
1130  // that starts the vm 'process'.
1131
1132  // Under the NPTL, getpid() returns the same pid as the
1133  // launcher thread rather than a unique pid per thread.
1134  // Use gettid() if you want the old pre NPTL behaviour.
1135
1136  // if you are looking for the result of a call to getpid() that
1137  // returns a unique pid for the calling thread, then look at the
1138  // OSThread::thread_id() method in osThread_bsd.hpp file
1139
1140  return (int)(_initial_pid ? _initial_pid : getpid());
1141}
1142
1143// DLL functions
1144
1145#define JNI_LIB_PREFIX "lib"
1146#ifdef __APPLE__
1147#define JNI_LIB_SUFFIX ".dylib"
1148#else
1149#define JNI_LIB_SUFFIX ".so"
1150#endif
1151
1152const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1153
1154// This must be hard coded because it's the system's temporary
1155// directory not the java application's temp directory, ala java.io.tmpdir.
1156#ifdef __APPLE__
1157// macosx has a secure per-user temporary directory
1158char temp_path_storage[PATH_MAX];
1159const char* os::get_temp_directory() {
1160  static char *temp_path = NULL;
1161  if (temp_path == NULL) {
1162    int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1163    if (pathSize == 0 || pathSize > PATH_MAX) {
1164      strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1165    }
1166    temp_path = temp_path_storage;
1167  }
1168  return temp_path;
1169}
1170#else /* __APPLE__ */
1171const char* os::get_temp_directory() { return "/tmp"; }
1172#endif /* __APPLE__ */
1173
1174static bool file_exists(const char* filename) {
1175  struct stat statbuf;
1176  if (filename == NULL || strlen(filename) == 0) {
1177    return false;
1178  }
1179  return os::stat(filename, &statbuf) == 0;
1180}
1181
1182bool os::dll_build_name(char* buffer, size_t buflen,
1183                        const char* pname, const char* fname) {
1184  bool retval = false;
1185  // Copied from libhpi
1186  const size_t pnamelen = pname ? strlen(pname) : 0;
1187
1188  // Return error on buffer overflow.
1189  if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1190    return retval;
1191  }
1192
1193  if (pnamelen == 0) {
1194    snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1195    retval = true;
1196  } else if (strchr(pname, *os::path_separator()) != NULL) {
1197    int n;
1198    char** pelements = split_path(pname, &n);
1199    for (int i = 0 ; i < n ; i++) {
1200      // Really shouldn't be NULL, but check can't hurt
1201      if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1202        continue; // skip the empty path values
1203      }
1204      snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1205          pelements[i], fname);
1206      if (file_exists(buffer)) {
1207        retval = true;
1208        break;
1209      }
1210    }
1211    // release the storage
1212    for (int i = 0 ; i < n ; i++) {
1213      if (pelements[i] != NULL) {
1214        FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1215      }
1216    }
1217    if (pelements != NULL) {
1218      FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1219    }
1220  } else {
1221    snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1222    retval = true;
1223  }
1224  return retval;
1225}
1226
1227const char* os::get_current_directory(char *buf, int buflen) {
1228  return getcwd(buf, buflen);
1229}
1230
1231// check if addr is inside libjvm.so
1232bool os::address_is_in_vm(address addr) {
1233  static address libjvm_base_addr;
1234  Dl_info dlinfo;
1235
1236  if (libjvm_base_addr == NULL) {
1237    dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1238    libjvm_base_addr = (address)dlinfo.dli_fbase;
1239    assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1240  }
1241
1242  if (dladdr((void *)addr, &dlinfo)) {
1243    if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1244  }
1245
1246  return false;
1247}
1248
1249
1250#define MACH_MAXSYMLEN 256
1251
1252bool os::dll_address_to_function_name(address addr, char *buf,
1253                                      int buflen, int *offset) {
1254  Dl_info dlinfo;
1255  char localbuf[MACH_MAXSYMLEN];
1256
1257  // dladdr will find names of dynamic functions only, but does
1258  // it set dli_fbase with mach_header address when it "fails" ?
1259  if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1260    if (buf != NULL) {
1261      if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1262        jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1263      }
1264    }
1265    if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1266    return true;
1267  } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1268    if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1269       buf, buflen, offset, dlinfo.dli_fname)) {
1270       return true;
1271    }
1272  }
1273
1274  // Handle non-dymanic manually:
1275  if (dlinfo.dli_fbase != NULL &&
1276      Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1277    if(!Decoder::demangle(localbuf, buf, buflen)) {
1278      jio_snprintf(buf, buflen, "%s", localbuf);
1279    }
1280    return true;
1281  }
1282  if (buf != NULL) buf[0] = '\0';
1283  if (offset != NULL) *offset = -1;
1284  return false;
1285}
1286
1287// ported from solaris version
1288bool os::dll_address_to_library_name(address addr, char* buf,
1289                                     int buflen, int* offset) {
1290  Dl_info dlinfo;
1291
1292  if (dladdr((void*)addr, &dlinfo)){
1293     if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1294     if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1295     return true;
1296  } else {
1297     if (buf) buf[0] = '\0';
1298     if (offset) *offset = -1;
1299     return false;
1300  }
1301}
1302
1303// Loads .dll/.so and
1304// in case of error it checks if .dll/.so was built for the
1305// same architecture as Hotspot is running on
1306
1307#ifdef __APPLE__
1308void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1309  void * result= ::dlopen(filename, RTLD_LAZY);
1310  if (result != NULL) {
1311    // Successful loading
1312    return result;
1313  }
1314
1315  // Read system error message into ebuf
1316  ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1317  ebuf[ebuflen-1]='\0';
1318
1319  return NULL;
1320}
1321#else
1322void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1323{
1324  void * result= ::dlopen(filename, RTLD_LAZY);
1325  if (result != NULL) {
1326    // Successful loading
1327    return result;
1328  }
1329
1330  Elf32_Ehdr elf_head;
1331
1332  // Read system error message into ebuf
1333  // It may or may not be overwritten below
1334  ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1335  ebuf[ebuflen-1]='\0';
1336  int diag_msg_max_length=ebuflen-strlen(ebuf);
1337  char* diag_msg_buf=ebuf+strlen(ebuf);
1338
1339  if (diag_msg_max_length==0) {
1340    // No more space in ebuf for additional diagnostics message
1341    return NULL;
1342  }
1343
1344
1345  int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1346
1347  if (file_descriptor < 0) {
1348    // Can't open library, report dlerror() message
1349    return NULL;
1350  }
1351
1352  bool failed_to_read_elf_head=
1353    (sizeof(elf_head)!=
1354        (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1355
1356  ::close(file_descriptor);
1357  if (failed_to_read_elf_head) {
1358    // file i/o error - report dlerror() msg
1359    return NULL;
1360  }
1361
1362  typedef struct {
1363    Elf32_Half  code;         // Actual value as defined in elf.h
1364    Elf32_Half  compat_class; // Compatibility of archs at VM's sense
1365    char        elf_class;    // 32 or 64 bit
1366    char        endianess;    // MSB or LSB
1367    char*       name;         // String representation
1368  } arch_t;
1369
1370  #ifndef EM_486
1371  #define EM_486          6               /* Intel 80486 */
1372  #endif
1373
1374  #ifndef EM_MIPS_RS3_LE
1375  #define EM_MIPS_RS3_LE  10              /* MIPS */
1376  #endif
1377
1378  #ifndef EM_PPC64
1379  #define EM_PPC64        21              /* PowerPC64 */
1380  #endif
1381
1382  #ifndef EM_S390
1383  #define EM_S390         22              /* IBM System/390 */
1384  #endif
1385
1386  #ifndef EM_IA_64
1387  #define EM_IA_64        50              /* HP/Intel IA-64 */
1388  #endif
1389
1390  #ifndef EM_X86_64
1391  #define EM_X86_64       62              /* AMD x86-64 */
1392  #endif
1393
1394  static const arch_t arch_array[]={
1395    {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1396    {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1397    {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1398    {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1399    {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1400    {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1401    {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1402    {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1403    {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1404    {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
1405    {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1406    {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1407    {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1408    {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1409    {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1410    {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1411  };
1412
1413  #if  (defined IA32)
1414    static  Elf32_Half running_arch_code=EM_386;
1415  #elif   (defined AMD64)
1416    static  Elf32_Half running_arch_code=EM_X86_64;
1417  #elif  (defined IA64)
1418    static  Elf32_Half running_arch_code=EM_IA_64;
1419  #elif  (defined __sparc) && (defined _LP64)
1420    static  Elf32_Half running_arch_code=EM_SPARCV9;
1421  #elif  (defined __sparc) && (!defined _LP64)
1422    static  Elf32_Half running_arch_code=EM_SPARC;
1423  #elif  (defined __powerpc64__)
1424    static  Elf32_Half running_arch_code=EM_PPC64;
1425  #elif  (defined __powerpc__)
1426    static  Elf32_Half running_arch_code=EM_PPC;
1427  #elif  (defined ARM)
1428    static  Elf32_Half running_arch_code=EM_ARM;
1429  #elif  (defined S390)
1430    static  Elf32_Half running_arch_code=EM_S390;
1431  #elif  (defined ALPHA)
1432    static  Elf32_Half running_arch_code=EM_ALPHA;
1433  #elif  (defined MIPSEL)
1434    static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1435  #elif  (defined PARISC)
1436    static  Elf32_Half running_arch_code=EM_PARISC;
1437  #elif  (defined MIPS)
1438    static  Elf32_Half running_arch_code=EM_MIPS;
1439  #elif  (defined M68K)
1440    static  Elf32_Half running_arch_code=EM_68K;
1441  #else
1442    #error Method os::dll_load requires that one of following is defined:\
1443         IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1444  #endif
1445
1446  // Identify compatability class for VM's architecture and library's architecture
1447  // Obtain string descriptions for architectures
1448
1449  arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1450  int running_arch_index=-1;
1451
1452  for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1453    if (running_arch_code == arch_array[i].code) {
1454      running_arch_index    = i;
1455    }
1456    if (lib_arch.code == arch_array[i].code) {
1457      lib_arch.compat_class = arch_array[i].compat_class;
1458      lib_arch.name         = arch_array[i].name;
1459    }
1460  }
1461
1462  assert(running_arch_index != -1,
1463    "Didn't find running architecture code (running_arch_code) in arch_array");
1464  if (running_arch_index == -1) {
1465    // Even though running architecture detection failed
1466    // we may still continue with reporting dlerror() message
1467    return NULL;
1468  }
1469
1470  if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1471    ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1472    return NULL;
1473  }
1474
1475#ifndef S390
1476  if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1477    ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1478    return NULL;
1479  }
1480#endif // !S390
1481
1482  if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1483    if ( lib_arch.name!=NULL ) {
1484      ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1485        " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1486        lib_arch.name, arch_array[running_arch_index].name);
1487    } else {
1488      ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1489      " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1490        lib_arch.code,
1491        arch_array[running_arch_index].name);
1492    }
1493  }
1494
1495  return NULL;
1496}
1497#endif /* !__APPLE__ */
1498
1499// XXX: Do we need a lock around this as per Linux?
1500void* os::dll_lookup(void* handle, const char* name) {
1501  return dlsym(handle, name);
1502}
1503
1504
1505static bool _print_ascii_file(const char* filename, outputStream* st) {
1506  int fd = ::open(filename, O_RDONLY);
1507  if (fd == -1) {
1508     return false;
1509  }
1510
1511  char buf[32];
1512  int bytes;
1513  while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1514    st->print_raw(buf, bytes);
1515  }
1516
1517  ::close(fd);
1518
1519  return true;
1520}
1521
1522void os::print_dll_info(outputStream *st) {
1523   st->print_cr("Dynamic libraries:");
1524#ifdef RTLD_DI_LINKMAP
1525    Dl_info dli;
1526    void *handle;
1527    Link_map *map;
1528    Link_map *p;
1529
1530    if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
1531        st->print_cr("Error: Cannot print dynamic libraries.");
1532        return;
1533    }
1534    handle = dlopen(dli.dli_fname, RTLD_LAZY);
1535    if (handle == NULL) {
1536        st->print_cr("Error: Cannot print dynamic libraries.");
1537        return;
1538    }
1539    dlinfo(handle, RTLD_DI_LINKMAP, &map);
1540    if (map == NULL) {
1541        st->print_cr("Error: Cannot print dynamic libraries.");
1542        return;
1543    }
1544
1545    while (map->l_prev != NULL)
1546        map = map->l_prev;
1547
1548    while (map != NULL) {
1549        st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1550        map = map->l_next;
1551    }
1552
1553    dlclose(handle);
1554#elif defined(__APPLE__)
1555    uint32_t count;
1556    uint32_t i;
1557
1558    count = _dyld_image_count();
1559    for (i = 1; i < count; i++) {
1560        const char *name = _dyld_get_image_name(i);
1561        intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1562        st->print_cr(PTR_FORMAT " \t%s", slide, name);
1563    }
1564#else
1565   st->print_cr("Error: Cannot print dynamic libraries.");
1566#endif
1567}
1568
1569void os::print_os_info_brief(outputStream* st) {
1570  st->print("Bsd");
1571
1572  os::Posix::print_uname_info(st);
1573}
1574
1575void os::print_os_info(outputStream* st) {
1576  st->print("OS:");
1577  st->print("Bsd");
1578
1579  os::Posix::print_uname_info(st);
1580
1581  os::Posix::print_rlimit_info(st);
1582
1583  os::Posix::print_load_average(st);
1584}
1585
1586void os::pd_print_cpu_info(outputStream* st) {
1587  // Nothing to do for now.
1588}
1589
1590void os::print_memory_info(outputStream* st) {
1591
1592  st->print("Memory:");
1593  st->print(" %dk page", os::vm_page_size()>>10);
1594
1595  st->print(", physical " UINT64_FORMAT "k",
1596            os::physical_memory() >> 10);
1597  st->print("(" UINT64_FORMAT "k free)",
1598            os::available_memory() >> 10);
1599  st->cr();
1600
1601  // meminfo
1602  st->print("\n/proc/meminfo:\n");
1603  _print_ascii_file("/proc/meminfo", st);
1604  st->cr();
1605}
1606
1607// Taken from /usr/include/bits/siginfo.h  Supposed to be architecture specific
1608// but they're the same for all the bsd arch that we support
1609// and they're the same for solaris but there's no common place to put this.
1610const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1611                          "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1612                          "ILL_COPROC", "ILL_BADSTK" };
1613
1614const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1615                          "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1616                          "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1617
1618const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1619
1620const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1621
1622void os::print_siginfo(outputStream* st, void* siginfo) {
1623  st->print("siginfo:");
1624
1625  const int buflen = 100;
1626  char buf[buflen];
1627  siginfo_t *si = (siginfo_t*)siginfo;
1628  st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1629  if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1630    st->print("si_errno=%s", buf);
1631  } else {
1632    st->print("si_errno=%d", si->si_errno);
1633  }
1634  const int c = si->si_code;
1635  assert(c > 0, "unexpected si_code");
1636  switch (si->si_signo) {
1637  case SIGILL:
1638    st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1639    st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1640    break;
1641  case SIGFPE:
1642    st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1643    st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1644    break;
1645  case SIGSEGV:
1646    st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1647    st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1648    break;
1649  case SIGBUS:
1650    st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1651    st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1652    break;
1653  default:
1654    st->print(", si_code=%d", si->si_code);
1655    // no si_addr
1656  }
1657
1658  if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1659      UseSharedSpaces) {
1660    FileMapInfo* mapinfo = FileMapInfo::current_info();
1661    if (mapinfo->is_in_shared_space(si->si_addr)) {
1662      st->print("\n\nError accessing class data sharing archive."   \
1663                " Mapped file inaccessible during execution, "      \
1664                " possible disk/network problem.");
1665    }
1666  }
1667  st->cr();
1668}
1669
1670
1671static void print_signal_handler(outputStream* st, int sig,
1672                                 char* buf, size_t buflen);
1673
1674void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1675  st->print_cr("Signal Handlers:");
1676  print_signal_handler(st, SIGSEGV, buf, buflen);
1677  print_signal_handler(st, SIGBUS , buf, buflen);
1678  print_signal_handler(st, SIGFPE , buf, buflen);
1679  print_signal_handler(st, SIGPIPE, buf, buflen);
1680  print_signal_handler(st, SIGXFSZ, buf, buflen);
1681  print_signal_handler(st, SIGILL , buf, buflen);
1682  print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1683  print_signal_handler(st, SR_signum, buf, buflen);
1684  print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1685  print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1686  print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1687  print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1688}
1689
1690static char saved_jvm_path[MAXPATHLEN] = {0};
1691
1692// Find the full path to the current module, libjvm
1693void os::jvm_path(char *buf, jint buflen) {
1694  // Error checking.
1695  if (buflen < MAXPATHLEN) {
1696    assert(false, "must use a large-enough buffer");
1697    buf[0] = '\0';
1698    return;
1699  }
1700  // Lazy resolve the path to current module.
1701  if (saved_jvm_path[0] != 0) {
1702    strcpy(buf, saved_jvm_path);
1703    return;
1704  }
1705
1706  char dli_fname[MAXPATHLEN];
1707  bool ret = dll_address_to_library_name(
1708                CAST_FROM_FN_PTR(address, os::jvm_path),
1709                dli_fname, sizeof(dli_fname), NULL);
1710  assert(ret != 0, "cannot locate libjvm");
1711  char *rp = realpath(dli_fname, buf);
1712  if (rp == NULL)
1713    return;
1714
1715  if (Arguments::created_by_gamma_launcher()) {
1716    // Support for the gamma launcher.  Typical value for buf is
1717    // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm".  If "/jre/lib/" appears at
1718    // the right place in the string, then assume we are installed in a JDK and
1719    // we're done.  Otherwise, check for a JAVA_HOME environment variable and
1720    // construct a path to the JVM being overridden.
1721
1722    const char *p = buf + strlen(buf) - 1;
1723    for (int count = 0; p > buf && count < 5; ++count) {
1724      for (--p; p > buf && *p != '/'; --p)
1725        /* empty */ ;
1726    }
1727
1728    if (strncmp(p, "/jre/lib/", 9) != 0) {
1729      // Look for JAVA_HOME in the environment.
1730      char* java_home_var = ::getenv("JAVA_HOME");
1731      if (java_home_var != NULL && java_home_var[0] != 0) {
1732        char* jrelib_p;
1733        int len;
1734
1735        // Check the current module name "libjvm"
1736        p = strrchr(buf, '/');
1737        assert(strstr(p, "/libjvm") == p, "invalid library name");
1738
1739        rp = realpath(java_home_var, buf);
1740        if (rp == NULL)
1741          return;
1742
1743        // determine if this is a legacy image or modules image
1744        // modules image doesn't have "jre" subdirectory
1745        len = strlen(buf);
1746        jrelib_p = buf + len;
1747
1748        // Add the appropriate library subdir
1749        snprintf(jrelib_p, buflen-len, "/jre/lib");
1750        if (0 != access(buf, F_OK)) {
1751          snprintf(jrelib_p, buflen-len, "/lib");
1752        }
1753
1754        // Add the appropriate client or server subdir
1755        len = strlen(buf);
1756        jrelib_p = buf + len;
1757        snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1758        if (0 != access(buf, F_OK)) {
1759          snprintf(jrelib_p, buflen-len, "");
1760        }
1761
1762        // If the path exists within JAVA_HOME, add the JVM library name
1763        // to complete the path to JVM being overridden.  Otherwise fallback
1764        // to the path to the current library.
1765        if (0 == access(buf, F_OK)) {
1766          // Use current module name "libjvm"
1767          len = strlen(buf);
1768          snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1769        } else {
1770          // Fall back to path of current library
1771          rp = realpath(dli_fname, buf);
1772          if (rp == NULL)
1773            return;
1774        }
1775      }
1776    }
1777  }
1778
1779  strcpy(saved_jvm_path, buf);
1780}
1781
1782void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1783  // no prefix required, not even "_"
1784}
1785
1786void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1787  // no suffix required
1788}
1789
1790////////////////////////////////////////////////////////////////////////////////
1791// sun.misc.Signal support
1792
1793static volatile jint sigint_count = 0;
1794
1795static void
1796UserHandler(int sig, void *siginfo, void *context) {
1797  // 4511530 - sem_post is serialized and handled by the manager thread. When
1798  // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1799  // don't want to flood the manager thread with sem_post requests.
1800  if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1801      return;
1802
1803  // Ctrl-C is pressed during error reporting, likely because the error
1804  // handler fails to abort. Let VM die immediately.
1805  if (sig == SIGINT && is_error_reported()) {
1806     os::die();
1807  }
1808
1809  os::signal_notify(sig);
1810}
1811
1812void* os::user_handler() {
1813  return CAST_FROM_FN_PTR(void*, UserHandler);
1814}
1815
1816extern "C" {
1817  typedef void (*sa_handler_t)(int);
1818  typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1819}
1820
1821void* os::signal(int signal_number, void* handler) {
1822  struct sigaction sigAct, oldSigAct;
1823
1824  sigfillset(&(sigAct.sa_mask));
1825  sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
1826  sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1827
1828  if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1829    // -1 means registration failed
1830    return (void *)-1;
1831  }
1832
1833  return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1834}
1835
1836void os::signal_raise(int signal_number) {
1837  ::raise(signal_number);
1838}
1839
1840/*
1841 * The following code is moved from os.cpp for making this
1842 * code platform specific, which it is by its very nature.
1843 */
1844
1845// Will be modified when max signal is changed to be dynamic
1846int os::sigexitnum_pd() {
1847  return NSIG;
1848}
1849
1850// a counter for each possible signal value
1851static volatile jint pending_signals[NSIG+1] = { 0 };
1852
1853// Bsd(POSIX) specific hand shaking semaphore.
1854#ifdef __APPLE__
1855static semaphore_t sig_sem;
1856#define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1857#define SEM_WAIT(sem)           semaphore_wait(sem);
1858#define SEM_POST(sem)           semaphore_signal(sem);
1859#else
1860static sem_t sig_sem;
1861#define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
1862#define SEM_WAIT(sem)           sem_wait(&sem);
1863#define SEM_POST(sem)           sem_post(&sem);
1864#endif
1865
1866void os::signal_init_pd() {
1867  // Initialize signal structures
1868  ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1869
1870  // Initialize signal semaphore
1871  ::SEM_INIT(sig_sem, 0);
1872}
1873
1874void os::signal_notify(int sig) {
1875  Atomic::inc(&pending_signals[sig]);
1876  ::SEM_POST(sig_sem);
1877}
1878
1879static int check_pending_signals(bool wait) {
1880  Atomic::store(0, &sigint_count);
1881  for (;;) {
1882    for (int i = 0; i < NSIG + 1; i++) {
1883      jint n = pending_signals[i];
1884      if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1885        return i;
1886      }
1887    }
1888    if (!wait) {
1889      return -1;
1890    }
1891    JavaThread *thread = JavaThread::current();
1892    ThreadBlockInVM tbivm(thread);
1893
1894    bool threadIsSuspended;
1895    do {
1896      thread->set_suspend_equivalent();
1897      // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1898      ::SEM_WAIT(sig_sem);
1899
1900      // were we externally suspended while we were waiting?
1901      threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1902      if (threadIsSuspended) {
1903        //
1904        // The semaphore has been incremented, but while we were waiting
1905        // another thread suspended us. We don't want to continue running
1906        // while suspended because that would surprise the thread that
1907        // suspended us.
1908        //
1909        ::SEM_POST(sig_sem);
1910
1911        thread->java_suspend_self();
1912      }
1913    } while (threadIsSuspended);
1914  }
1915}
1916
1917int os::signal_lookup() {
1918  return check_pending_signals(false);
1919}
1920
1921int os::signal_wait() {
1922  return check_pending_signals(true);
1923}
1924
1925////////////////////////////////////////////////////////////////////////////////
1926// Virtual Memory
1927
1928int os::vm_page_size() {
1929  // Seems redundant as all get out
1930  assert(os::Bsd::page_size() != -1, "must call os::init");
1931  return os::Bsd::page_size();
1932}
1933
1934// Solaris allocates memory by pages.
1935int os::vm_allocation_granularity() {
1936  assert(os::Bsd::page_size() != -1, "must call os::init");
1937  return os::Bsd::page_size();
1938}
1939
1940// Rationale behind this function:
1941//  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1942//  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1943//  samples for JITted code. Here we create private executable mapping over the code cache
1944//  and then we can use standard (well, almost, as mapping can change) way to provide
1945//  info for the reporting script by storing timestamp and location of symbol
1946void bsd_wrap_code(char* base, size_t size) {
1947  static volatile jint cnt = 0;
1948
1949  if (!UseOprofile) {
1950    return;
1951  }
1952
1953  char buf[PATH_MAX + 1];
1954  int num = Atomic::add(1, &cnt);
1955
1956  snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1957           os::get_temp_directory(), os::current_process_id(), num);
1958  unlink(buf);
1959
1960  int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1961
1962  if (fd != -1) {
1963    off_t rv = ::lseek(fd, size-2, SEEK_SET);
1964    if (rv != (off_t)-1) {
1965      if (::write(fd, "", 1) == 1) {
1966        mmap(base, size,
1967             PROT_READ|PROT_WRITE|PROT_EXEC,
1968             MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1969      }
1970    }
1971    ::close(fd);
1972    unlink(buf);
1973  }
1974}
1975
1976// NOTE: Bsd kernel does not really reserve the pages for us.
1977//       All it does is to check if there are enough free pages
1978//       left at the time of mmap(). This could be a potential
1979//       problem.
1980bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1981  int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1982#ifdef __OpenBSD__
1983  // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1984  return ::mprotect(addr, size, prot) == 0;
1985#else
1986  uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1987                                   MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1988  return res != (uintptr_t) MAP_FAILED;
1989#endif
1990}
1991
1992
1993bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1994                       bool exec) {
1995  return commit_memory(addr, size, exec);
1996}
1997
1998void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1999}
2000
2001void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2002  ::madvise(addr, bytes, MADV_DONTNEED);
2003}
2004
2005void os::numa_make_global(char *addr, size_t bytes) {
2006}
2007
2008void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2009}
2010
2011bool os::numa_topology_changed()   { return false; }
2012
2013size_t os::numa_get_groups_num() {
2014  return 1;
2015}
2016
2017int os::numa_get_group_id() {
2018  return 0;
2019}
2020
2021size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2022  if (size > 0) {
2023    ids[0] = 0;
2024    return 1;
2025  }
2026  return 0;
2027}
2028
2029bool os::get_page_info(char *start, page_info* info) {
2030  return false;
2031}
2032
2033char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2034  return end;
2035}
2036
2037
2038bool os::pd_uncommit_memory(char* addr, size_t size) {
2039#ifdef __OpenBSD__
2040  // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2041  return ::mprotect(addr, size, PROT_NONE) == 0;
2042#else
2043  uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2044                MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2045  return res  != (uintptr_t) MAP_FAILED;
2046#endif
2047}
2048
2049bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2050  return os::commit_memory(addr, size);
2051}
2052
2053// If this is a growable mapping, remove the guard pages entirely by
2054// munmap()ping them.  If not, just call uncommit_memory().
2055bool os::remove_stack_guard_pages(char* addr, size_t size) {
2056  return os::uncommit_memory(addr, size);
2057}
2058
2059static address _highest_vm_reserved_address = NULL;
2060
2061// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2062// at 'requested_addr'. If there are existing memory mappings at the same
2063// location, however, they will be overwritten. If 'fixed' is false,
2064// 'requested_addr' is only treated as a hint, the return value may or
2065// may not start from the requested address. Unlike Bsd mmap(), this
2066// function returns NULL to indicate failure.
2067static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2068  char * addr;
2069  int flags;
2070
2071  flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2072  if (fixed) {
2073    assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2074    flags |= MAP_FIXED;
2075  }
2076
2077  // Map uncommitted pages PROT_READ and PROT_WRITE, change access
2078  // to PROT_EXEC if executable when we commit the page.
2079  addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
2080                       flags, -1, 0);
2081
2082  if (addr != MAP_FAILED) {
2083    // anon_mmap() should only get called during VM initialization,
2084    // don't need lock (actually we can skip locking even it can be called
2085    // from multiple threads, because _highest_vm_reserved_address is just a
2086    // hint about the upper limit of non-stack memory regions.)
2087    if ((address)addr + bytes > _highest_vm_reserved_address) {
2088      _highest_vm_reserved_address = (address)addr + bytes;
2089    }
2090  }
2091
2092  return addr == MAP_FAILED ? NULL : addr;
2093}
2094
2095// Don't update _highest_vm_reserved_address, because there might be memory
2096// regions above addr + size. If so, releasing a memory region only creates
2097// a hole in the address space, it doesn't help prevent heap-stack collision.
2098//
2099static int anon_munmap(char * addr, size_t size) {
2100  return ::munmap(addr, size) == 0;
2101}
2102
2103char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2104                         size_t alignment_hint) {
2105  return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2106}
2107
2108bool os::pd_release_memory(char* addr, size_t size) {
2109  return anon_munmap(addr, size);
2110}
2111
2112static address highest_vm_reserved_address() {
2113  return _highest_vm_reserved_address;
2114}
2115
2116static bool bsd_mprotect(char* addr, size_t size, int prot) {
2117  // Bsd wants the mprotect address argument to be page aligned.
2118  char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2119
2120  // According to SUSv3, mprotect() should only be used with mappings
2121  // established by mmap(), and mmap() always maps whole pages. Unaligned
2122  // 'addr' likely indicates problem in the VM (e.g. trying to change
2123  // protection of malloc'ed or statically allocated memory). Check the
2124  // caller if you hit this assert.
2125  assert(addr == bottom, "sanity check");
2126
2127  size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2128  return ::mprotect(bottom, size, prot) == 0;
2129}
2130
2131// Set protections specified
2132bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2133                        bool is_committed) {
2134  unsigned int p = 0;
2135  switch (prot) {
2136  case MEM_PROT_NONE: p = PROT_NONE; break;
2137  case MEM_PROT_READ: p = PROT_READ; break;
2138  case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
2139  case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2140  default:
2141    ShouldNotReachHere();
2142  }
2143  // is_committed is unused.
2144  return bsd_mprotect(addr, bytes, p);
2145}
2146
2147bool os::guard_memory(char* addr, size_t size) {
2148  return bsd_mprotect(addr, size, PROT_NONE);
2149}
2150
2151bool os::unguard_memory(char* addr, size_t size) {
2152  return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2153}
2154
2155bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2156  return false;
2157}
2158
2159/*
2160* Set the coredump_filter bits to include largepages in core dump (bit 6)
2161*
2162* From the coredump_filter documentation:
2163*
2164* - (bit 0) anonymous private memory
2165* - (bit 1) anonymous shared memory
2166* - (bit 2) file-backed private memory
2167* - (bit 3) file-backed shared memory
2168* - (bit 4) ELF header pages in file-backed private memory areas (it is
2169*           effective only if the bit 2 is cleared)
2170* - (bit 5) hugetlb private memory
2171* - (bit 6) hugetlb shared memory
2172*/
2173static void set_coredump_filter(void) {
2174  FILE *f;
2175  long cdm;
2176
2177  if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
2178    return;
2179  }
2180
2181  if (fscanf(f, "%lx", &cdm) != 1) {
2182    fclose(f);
2183    return;
2184  }
2185
2186  rewind(f);
2187
2188  if ((cdm & LARGEPAGES_BIT) == 0) {
2189    cdm |= LARGEPAGES_BIT;
2190    fprintf(f, "%#lx", cdm);
2191  }
2192
2193  fclose(f);
2194}
2195
2196// Large page support
2197
2198static size_t _large_page_size = 0;
2199
2200void os::large_page_init() {
2201}
2202
2203
2204char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2205  // "exec" is passed in but not used.  Creating the shared image for
2206  // the code cache doesn't have an SHM_X executable permission to check.
2207  assert(UseLargePages && UseSHM, "only for SHM large pages");
2208
2209  key_t key = IPC_PRIVATE;
2210  char *addr;
2211
2212  bool warn_on_failure = UseLargePages &&
2213                        (!FLAG_IS_DEFAULT(UseLargePages) ||
2214                         !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2215                        );
2216  char msg[128];
2217
2218  // Create a large shared memory region to attach to based on size.
2219  // Currently, size is the total size of the heap
2220  int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2221  if (shmid == -1) {
2222     // Possible reasons for shmget failure:
2223     // 1. shmmax is too small for Java heap.
2224     //    > check shmmax value: cat /proc/sys/kernel/shmmax
2225     //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2226     // 2. not enough large page memory.
2227     //    > check available large pages: cat /proc/meminfo
2228     //    > increase amount of large pages:
2229     //          echo new_value > /proc/sys/vm/nr_hugepages
2230     //      Note 1: different Bsd may use different name for this property,
2231     //            e.g. on Redhat AS-3 it is "hugetlb_pool".
2232     //      Note 2: it's possible there's enough physical memory available but
2233     //            they are so fragmented after a long run that they can't
2234     //            coalesce into large pages. Try to reserve large pages when
2235     //            the system is still "fresh".
2236     if (warn_on_failure) {
2237       jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2238       warning(msg);
2239     }
2240     return NULL;
2241  }
2242
2243  // attach to the region
2244  addr = (char*)shmat(shmid, req_addr, 0);
2245  int err = errno;
2246
2247  // Remove shmid. If shmat() is successful, the actual shared memory segment
2248  // will be deleted when it's detached by shmdt() or when the process
2249  // terminates. If shmat() is not successful this will remove the shared
2250  // segment immediately.
2251  shmctl(shmid, IPC_RMID, NULL);
2252
2253  if ((intptr_t)addr == -1) {
2254     if (warn_on_failure) {
2255       jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2256       warning(msg);
2257     }
2258     return NULL;
2259  }
2260
2261  return addr;
2262}
2263
2264bool os::release_memory_special(char* base, size_t bytes) {
2265  // detaching the SHM segment will also delete it, see reserve_memory_special()
2266  int rslt = shmdt(base);
2267  return rslt == 0;
2268}
2269
2270size_t os::large_page_size() {
2271  return _large_page_size;
2272}
2273
2274// HugeTLBFS allows application to commit large page memory on demand;
2275// with SysV SHM the entire memory region must be allocated as shared
2276// memory.
2277bool os::can_commit_large_page_memory() {
2278  return UseHugeTLBFS;
2279}
2280
2281bool os::can_execute_large_page_memory() {
2282  return UseHugeTLBFS;
2283}
2284
2285// Reserve memory at an arbitrary address, only if that area is
2286// available (and not reserved for something else).
2287
2288char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2289  const int max_tries = 10;
2290  char* base[max_tries];
2291  size_t size[max_tries];
2292  const size_t gap = 0x000000;
2293
2294  // Assert only that the size is a multiple of the page size, since
2295  // that's all that mmap requires, and since that's all we really know
2296  // about at this low abstraction level.  If we need higher alignment,
2297  // we can either pass an alignment to this method or verify alignment
2298  // in one of the methods further up the call chain.  See bug 5044738.
2299  assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2300
2301  // Repeatedly allocate blocks until the block is allocated at the
2302  // right spot. Give up after max_tries. Note that reserve_memory() will
2303  // automatically update _highest_vm_reserved_address if the call is
2304  // successful. The variable tracks the highest memory address every reserved
2305  // by JVM. It is used to detect heap-stack collision if running with
2306  // fixed-stack BsdThreads. Because here we may attempt to reserve more
2307  // space than needed, it could confuse the collision detecting code. To
2308  // solve the problem, save current _highest_vm_reserved_address and
2309  // calculate the correct value before return.
2310  address old_highest = _highest_vm_reserved_address;
2311
2312  // Bsd mmap allows caller to pass an address as hint; give it a try first,
2313  // if kernel honors the hint then we can return immediately.
2314  char * addr = anon_mmap(requested_addr, bytes, false);
2315  if (addr == requested_addr) {
2316     return requested_addr;
2317  }
2318
2319  if (addr != NULL) {
2320     // mmap() is successful but it fails to reserve at the requested address
2321     anon_munmap(addr, bytes);
2322  }
2323
2324  int i;
2325  for (i = 0; i < max_tries; ++i) {
2326    base[i] = reserve_memory(bytes);
2327
2328    if (base[i] != NULL) {
2329      // Is this the block we wanted?
2330      if (base[i] == requested_addr) {
2331        size[i] = bytes;
2332        break;
2333      }
2334
2335      // Does this overlap the block we wanted? Give back the overlapped
2336      // parts and try again.
2337
2338      size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2339      if (top_overlap >= 0 && top_overlap < bytes) {
2340        unmap_memory(base[i], top_overlap);
2341        base[i] += top_overlap;
2342        size[i] = bytes - top_overlap;
2343      } else {
2344        size_t bottom_overlap = base[i] + bytes - requested_addr;
2345        if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2346          unmap_memory(requested_addr, bottom_overlap);
2347          size[i] = bytes - bottom_overlap;
2348        } else {
2349          size[i] = bytes;
2350        }
2351      }
2352    }
2353  }
2354
2355  // Give back the unused reserved pieces.
2356
2357  for (int j = 0; j < i; ++j) {
2358    if (base[j] != NULL) {
2359      unmap_memory(base[j], size[j]);
2360    }
2361  }
2362
2363  if (i < max_tries) {
2364    _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2365    return requested_addr;
2366  } else {
2367    _highest_vm_reserved_address = old_highest;
2368    return NULL;
2369  }
2370}
2371
2372size_t os::read(int fd, void *buf, unsigned int nBytes) {
2373  RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2374}
2375
2376// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2377// Solaris uses poll(), bsd uses park().
2378// Poll() is likely a better choice, assuming that Thread.interrupt()
2379// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2380// SIGSEGV, see 4355769.
2381
2382int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2383  assert(thread == Thread::current(),  "thread consistency check");
2384
2385  ParkEvent * const slp = thread->_SleepEvent ;
2386  slp->reset() ;
2387  OrderAccess::fence() ;
2388
2389  if (interruptible) {
2390    jlong prevtime = javaTimeNanos();
2391
2392    for (;;) {
2393      if (os::is_interrupted(thread, true)) {
2394        return OS_INTRPT;
2395      }
2396
2397      jlong newtime = javaTimeNanos();
2398
2399      if (newtime - prevtime < 0) {
2400        // time moving backwards, should only happen if no monotonic clock
2401        // not a guarantee() because JVM should not abort on kernel/glibc bugs
2402        assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2403      } else {
2404        millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2405      }
2406
2407      if(millis <= 0) {
2408        return OS_OK;
2409      }
2410
2411      prevtime = newtime;
2412
2413      {
2414        assert(thread->is_Java_thread(), "sanity check");
2415        JavaThread *jt = (JavaThread *) thread;
2416        ThreadBlockInVM tbivm(jt);
2417        OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2418
2419        jt->set_suspend_equivalent();
2420        // cleared by handle_special_suspend_equivalent_condition() or
2421        // java_suspend_self() via check_and_wait_while_suspended()
2422
2423        slp->park(millis);
2424
2425        // were we externally suspended while we were waiting?
2426        jt->check_and_wait_while_suspended();
2427      }
2428    }
2429  } else {
2430    OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2431    jlong prevtime = javaTimeNanos();
2432
2433    for (;;) {
2434      // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2435      // the 1st iteration ...
2436      jlong newtime = javaTimeNanos();
2437
2438      if (newtime - prevtime < 0) {
2439        // time moving backwards, should only happen if no monotonic clock
2440        // not a guarantee() because JVM should not abort on kernel/glibc bugs
2441        assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2442      } else {
2443        millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2444      }
2445
2446      if(millis <= 0) break ;
2447
2448      prevtime = newtime;
2449      slp->park(millis);
2450    }
2451    return OS_OK ;
2452  }
2453}
2454
2455int os::naked_sleep() {
2456  // %% make the sleep time an integer flag. for now use 1 millisec.
2457  return os::sleep(Thread::current(), 1, false);
2458}
2459
2460// Sleep forever; naked call to OS-specific sleep; use with CAUTION
2461void os::infinite_sleep() {
2462  while (true) {    // sleep forever ...
2463    ::sleep(100);   // ... 100 seconds at a time
2464  }
2465}
2466
2467// Used to convert frequent JVM_Yield() to nops
2468bool os::dont_yield() {
2469  return DontYieldALot;
2470}
2471
2472void os::yield() {
2473  sched_yield();
2474}
2475
2476os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2477
2478void os::yield_all(int attempts) {
2479  // Yields to all threads, including threads with lower priorities
2480  // Threads on Bsd are all with same priority. The Solaris style
2481  // os::yield_all() with nanosleep(1ms) is not necessary.
2482  sched_yield();
2483}
2484
2485// Called from the tight loops to possibly influence time-sharing heuristics
2486void os::loop_breaker(int attempts) {
2487  os::yield_all(attempts);
2488}
2489
2490////////////////////////////////////////////////////////////////////////////////
2491// thread priority support
2492
2493// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2494// only supports dynamic priority, static priority must be zero. For real-time
2495// applications, Bsd supports SCHED_RR which allows static priority (1-99).
2496// However, for large multi-threaded applications, SCHED_RR is not only slower
2497// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2498// of 5 runs - Sep 2005).
2499//
2500// The following code actually changes the niceness of kernel-thread/LWP. It
2501// has an assumption that setpriority() only modifies one kernel-thread/LWP,
2502// not the entire user process, and user level threads are 1:1 mapped to kernel
2503// threads. It has always been the case, but could change in the future. For
2504// this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2505// It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2506
2507#if !defined(__APPLE__)
2508int os::java_to_os_priority[CriticalPriority + 1] = {
2509  19,              // 0 Entry should never be used
2510
2511   0,              // 1 MinPriority
2512   3,              // 2
2513   6,              // 3
2514
2515  10,              // 4
2516  15,              // 5 NormPriority
2517  18,              // 6
2518
2519  21,              // 7
2520  25,              // 8
2521  28,              // 9 NearMaxPriority
2522
2523  31,              // 10 MaxPriority
2524
2525  31               // 11 CriticalPriority
2526};
2527#else
2528/* Using Mach high-level priority assignments */
2529int os::java_to_os_priority[CriticalPriority + 1] = {
2530   0,              // 0 Entry should never be used (MINPRI_USER)
2531
2532  27,              // 1 MinPriority
2533  28,              // 2
2534  29,              // 3
2535
2536  30,              // 4
2537  31,              // 5 NormPriority (BASEPRI_DEFAULT)
2538  32,              // 6
2539
2540  33,              // 7
2541  34,              // 8
2542  35,              // 9 NearMaxPriority
2543
2544  36,              // 10 MaxPriority
2545
2546  36               // 11 CriticalPriority
2547};
2548#endif
2549
2550static int prio_init() {
2551  if (ThreadPriorityPolicy == 1) {
2552    // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2553    // if effective uid is not root. Perhaps, a more elegant way of doing
2554    // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2555    if (geteuid() != 0) {
2556      if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2557        warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2558      }
2559      ThreadPriorityPolicy = 0;
2560    }
2561  }
2562  if (UseCriticalJavaThreadPriority) {
2563    os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2564  }
2565  return 0;
2566}
2567
2568OSReturn os::set_native_priority(Thread* thread, int newpri) {
2569  if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2570
2571#ifdef __OpenBSD__
2572  // OpenBSD pthread_setprio starves low priority threads
2573  return OS_OK;
2574#elif defined(__FreeBSD__)
2575  int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2576#elif defined(__APPLE__) || defined(__NetBSD__)
2577  struct sched_param sp;
2578  int policy;
2579  pthread_t self = pthread_self();
2580
2581  if (pthread_getschedparam(self, &policy, &sp) != 0)
2582    return OS_ERR;
2583
2584  sp.sched_priority = newpri;
2585  if (pthread_setschedparam(self, policy, &sp) != 0)
2586    return OS_ERR;
2587
2588  return OS_OK;
2589#else
2590  int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2591  return (ret == 0) ? OS_OK : OS_ERR;
2592#endif
2593}
2594
2595OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2596  if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2597    *priority_ptr = java_to_os_priority[NormPriority];
2598    return OS_OK;
2599  }
2600
2601  errno = 0;
2602#if defined(__OpenBSD__) || defined(__FreeBSD__)
2603  *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2604#elif defined(__APPLE__) || defined(__NetBSD__)
2605  int policy;
2606  struct sched_param sp;
2607
2608  pthread_getschedparam(pthread_self(), &policy, &sp);
2609  *priority_ptr = sp.sched_priority;
2610#else
2611  *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2612#endif
2613  return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2614}
2615
2616// Hint to the underlying OS that a task switch would not be good.
2617// Void return because it's a hint and can fail.
2618void os::hint_no_preempt() {}
2619
2620////////////////////////////////////////////////////////////////////////////////
2621// suspend/resume support
2622
2623//  the low-level signal-based suspend/resume support is a remnant from the
2624//  old VM-suspension that used to be for java-suspension, safepoints etc,
2625//  within hotspot. Now there is a single use-case for this:
2626//    - calling get_thread_pc() on the VMThread by the flat-profiler task
2627//      that runs in the watcher thread.
2628//  The remaining code is greatly simplified from the more general suspension
2629//  code that used to be used.
2630//
2631//  The protocol is quite simple:
2632//  - suspend:
2633//      - sends a signal to the target thread
2634//      - polls the suspend state of the osthread using a yield loop
2635//      - target thread signal handler (SR_handler) sets suspend state
2636//        and blocks in sigsuspend until continued
2637//  - resume:
2638//      - sets target osthread state to continue
2639//      - sends signal to end the sigsuspend loop in the SR_handler
2640//
2641//  Note that the SR_lock plays no role in this suspend/resume protocol.
2642//
2643
2644static void resume_clear_context(OSThread *osthread) {
2645  osthread->set_ucontext(NULL);
2646  osthread->set_siginfo(NULL);
2647
2648  // notify the suspend action is completed, we have now resumed
2649  osthread->sr.clear_suspended();
2650}
2651
2652static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2653  osthread->set_ucontext(context);
2654  osthread->set_siginfo(siginfo);
2655}
2656
2657//
2658// Handler function invoked when a thread's execution is suspended or
2659// resumed. We have to be careful that only async-safe functions are
2660// called here (Note: most pthread functions are not async safe and
2661// should be avoided.)
2662//
2663// Note: sigwait() is a more natural fit than sigsuspend() from an
2664// interface point of view, but sigwait() prevents the signal hander
2665// from being run. libpthread would get very confused by not having
2666// its signal handlers run and prevents sigwait()'s use with the
2667// mutex granting granting signal.
2668//
2669// Currently only ever called on the VMThread
2670//
2671static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2672  // Save and restore errno to avoid confusing native code with EINTR
2673  // after sigsuspend.
2674  int old_errno = errno;
2675
2676  Thread* thread = Thread::current();
2677  OSThread* osthread = thread->osthread();
2678  assert(thread->is_VM_thread(), "Must be VMThread");
2679  // read current suspend action
2680  int action = osthread->sr.suspend_action();
2681  if (action == SR_SUSPEND) {
2682    suspend_save_context(osthread, siginfo, context);
2683
2684    // Notify the suspend action is about to be completed. do_suspend()
2685    // waits until SR_SUSPENDED is set and then returns. We will wait
2686    // here for a resume signal and that completes the suspend-other
2687    // action. do_suspend/do_resume is always called as a pair from
2688    // the same thread - so there are no races
2689
2690    // notify the caller
2691    osthread->sr.set_suspended();
2692
2693    sigset_t suspend_set;  // signals for sigsuspend()
2694
2695    // get current set of blocked signals and unblock resume signal
2696    pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2697    sigdelset(&suspend_set, SR_signum);
2698
2699    // wait here until we are resumed
2700    do {
2701      sigsuspend(&suspend_set);
2702      // ignore all returns until we get a resume signal
2703    } while (osthread->sr.suspend_action() != SR_CONTINUE);
2704
2705    resume_clear_context(osthread);
2706
2707  } else {
2708    assert(action == SR_CONTINUE, "unexpected sr action");
2709    // nothing special to do - just leave the handler
2710  }
2711
2712  errno = old_errno;
2713}
2714
2715
2716static int SR_initialize() {
2717  struct sigaction act;
2718  char *s;
2719  /* Get signal number to use for suspend/resume */
2720  if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2721    int sig = ::strtol(s, 0, 10);
2722    if (sig > 0 || sig < NSIG) {
2723        SR_signum = sig;
2724    }
2725  }
2726
2727  assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2728        "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2729
2730  sigemptyset(&SR_sigset);
2731  sigaddset(&SR_sigset, SR_signum);
2732
2733  /* Set up signal handler for suspend/resume */
2734  act.sa_flags = SA_RESTART|SA_SIGINFO;
2735  act.sa_handler = (void (*)(int)) SR_handler;
2736
2737  // SR_signum is blocked by default.
2738  // 4528190 - We also need to block pthread restart signal (32 on all
2739  // supported Bsd platforms). Note that BsdThreads need to block
2740  // this signal for all threads to work properly. So we don't have
2741  // to use hard-coded signal number when setting up the mask.
2742  pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2743
2744  if (sigaction(SR_signum, &act, 0) == -1) {
2745    return -1;
2746  }
2747
2748  // Save signal flag
2749  os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2750  return 0;
2751}
2752
2753static int SR_finalize() {
2754  return 0;
2755}
2756
2757
2758// returns true on success and false on error - really an error is fatal
2759// but this seems the normal response to library errors
2760static bool do_suspend(OSThread* osthread) {
2761  // mark as suspended and send signal
2762  osthread->sr.set_suspend_action(SR_SUSPEND);
2763  int status = pthread_kill(osthread->pthread_id(), SR_signum);
2764  assert_status(status == 0, status, "pthread_kill");
2765
2766  // check status and wait until notified of suspension
2767  if (status == 0) {
2768    for (int i = 0; !osthread->sr.is_suspended(); i++) {
2769      os::yield_all(i);
2770    }
2771    osthread->sr.set_suspend_action(SR_NONE);
2772    return true;
2773  }
2774  else {
2775    osthread->sr.set_suspend_action(SR_NONE);
2776    return false;
2777  }
2778}
2779
2780static void do_resume(OSThread* osthread) {
2781  assert(osthread->sr.is_suspended(), "thread should be suspended");
2782  osthread->sr.set_suspend_action(SR_CONTINUE);
2783
2784  int status = pthread_kill(osthread->pthread_id(), SR_signum);
2785  assert_status(status == 0, status, "pthread_kill");
2786  // check status and wait unit notified of resumption
2787  if (status == 0) {
2788    for (int i = 0; osthread->sr.is_suspended(); i++) {
2789      os::yield_all(i);
2790    }
2791  }
2792  osthread->sr.set_suspend_action(SR_NONE);
2793}
2794
2795////////////////////////////////////////////////////////////////////////////////
2796// interrupt support
2797
2798void os::interrupt(Thread* thread) {
2799  assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2800    "possibility of dangling Thread pointer");
2801
2802  OSThread* osthread = thread->osthread();
2803
2804  if (!osthread->interrupted()) {
2805    osthread->set_interrupted(true);
2806    // More than one thread can get here with the same value of osthread,
2807    // resulting in multiple notifications.  We do, however, want the store
2808    // to interrupted() to be visible to other threads before we execute unpark().
2809    OrderAccess::fence();
2810    ParkEvent * const slp = thread->_SleepEvent ;
2811    if (slp != NULL) slp->unpark() ;
2812  }
2813
2814  // For JSR166. Unpark even if interrupt status already was set
2815  if (thread->is_Java_thread())
2816    ((JavaThread*)thread)->parker()->unpark();
2817
2818  ParkEvent * ev = thread->_ParkEvent ;
2819  if (ev != NULL) ev->unpark() ;
2820
2821}
2822
2823bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2824  assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2825    "possibility of dangling Thread pointer");
2826
2827  OSThread* osthread = thread->osthread();
2828
2829  bool interrupted = osthread->interrupted();
2830
2831  if (interrupted && clear_interrupted) {
2832    osthread->set_interrupted(false);
2833    // consider thread->_SleepEvent->reset() ... optional optimization
2834  }
2835
2836  return interrupted;
2837}
2838
2839///////////////////////////////////////////////////////////////////////////////////
2840// signal handling (except suspend/resume)
2841
2842// This routine may be used by user applications as a "hook" to catch signals.
2843// The user-defined signal handler must pass unrecognized signals to this
2844// routine, and if it returns true (non-zero), then the signal handler must
2845// return immediately.  If the flag "abort_if_unrecognized" is true, then this
2846// routine will never retun false (zero), but instead will execute a VM panic
2847// routine kill the process.
2848//
2849// If this routine returns false, it is OK to call it again.  This allows
2850// the user-defined signal handler to perform checks either before or after
2851// the VM performs its own checks.  Naturally, the user code would be making
2852// a serious error if it tried to handle an exception (such as a null check
2853// or breakpoint) that the VM was generating for its own correct operation.
2854//
2855// This routine may recognize any of the following kinds of signals:
2856//    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2857// It should be consulted by handlers for any of those signals.
2858//
2859// The caller of this routine must pass in the three arguments supplied
2860// to the function referred to in the "sa_sigaction" (not the "sa_handler")
2861// field of the structure passed to sigaction().  This routine assumes that
2862// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2863//
2864// Note that the VM will print warnings if it detects conflicting signal
2865// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2866//
2867extern "C" JNIEXPORT int
2868JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2869                        void* ucontext, int abort_if_unrecognized);
2870
2871void signalHandler(int sig, siginfo_t* info, void* uc) {
2872  assert(info != NULL && uc != NULL, "it must be old kernel");
2873  JVM_handle_bsd_signal(sig, info, uc, true);
2874}
2875
2876
2877// This boolean allows users to forward their own non-matching signals
2878// to JVM_handle_bsd_signal, harmlessly.
2879bool os::Bsd::signal_handlers_are_installed = false;
2880
2881// For signal-chaining
2882struct sigaction os::Bsd::sigact[MAXSIGNUM];
2883unsigned int os::Bsd::sigs = 0;
2884bool os::Bsd::libjsig_is_loaded = false;
2885typedef struct sigaction *(*get_signal_t)(int);
2886get_signal_t os::Bsd::get_signal_action = NULL;
2887
2888struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2889  struct sigaction *actp = NULL;
2890
2891  if (libjsig_is_loaded) {
2892    // Retrieve the old signal handler from libjsig
2893    actp = (*get_signal_action)(sig);
2894  }
2895  if (actp == NULL) {
2896    // Retrieve the preinstalled signal handler from jvm
2897    actp = get_preinstalled_handler(sig);
2898  }
2899
2900  return actp;
2901}
2902
2903static bool call_chained_handler(struct sigaction *actp, int sig,
2904                                 siginfo_t *siginfo, void *context) {
2905  // Call the old signal handler
2906  if (actp->sa_handler == SIG_DFL) {
2907    // It's more reasonable to let jvm treat it as an unexpected exception
2908    // instead of taking the default action.
2909    return false;
2910  } else if (actp->sa_handler != SIG_IGN) {
2911    if ((actp->sa_flags & SA_NODEFER) == 0) {
2912      // automaticlly block the signal
2913      sigaddset(&(actp->sa_mask), sig);
2914    }
2915
2916    sa_handler_t hand;
2917    sa_sigaction_t sa;
2918    bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2919    // retrieve the chained handler
2920    if (siginfo_flag_set) {
2921      sa = actp->sa_sigaction;
2922    } else {
2923      hand = actp->sa_handler;
2924    }
2925
2926    if ((actp->sa_flags & SA_RESETHAND) != 0) {
2927      actp->sa_handler = SIG_DFL;
2928    }
2929
2930    // try to honor the signal mask
2931    sigset_t oset;
2932    pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2933
2934    // call into the chained handler
2935    if (siginfo_flag_set) {
2936      (*sa)(sig, siginfo, context);
2937    } else {
2938      (*hand)(sig);
2939    }
2940
2941    // restore the signal mask
2942    pthread_sigmask(SIG_SETMASK, &oset, 0);
2943  }
2944  // Tell jvm's signal handler the signal is taken care of.
2945  return true;
2946}
2947
2948bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2949  bool chained = false;
2950  // signal-chaining
2951  if (UseSignalChaining) {
2952    struct sigaction *actp = get_chained_signal_action(sig);
2953    if (actp != NULL) {
2954      chained = call_chained_handler(actp, sig, siginfo, context);
2955    }
2956  }
2957  return chained;
2958}
2959
2960struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
2961  if ((( (unsigned int)1 << sig ) & sigs) != 0) {
2962    return &sigact[sig];
2963  }
2964  return NULL;
2965}
2966
2967void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
2968  assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2969  sigact[sig] = oldAct;
2970  sigs |= (unsigned int)1 << sig;
2971}
2972
2973// for diagnostic
2974int os::Bsd::sigflags[MAXSIGNUM];
2975
2976int os::Bsd::get_our_sigflags(int sig) {
2977  assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2978  return sigflags[sig];
2979}
2980
2981void os::Bsd::set_our_sigflags(int sig, int flags) {
2982  assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2983  sigflags[sig] = flags;
2984}
2985
2986void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2987  // Check for overwrite.
2988  struct sigaction oldAct;
2989  sigaction(sig, (struct sigaction*)NULL, &oldAct);
2990
2991  void* oldhand = oldAct.sa_sigaction
2992                ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
2993                : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
2994  if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2995      oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2996      oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2997    if (AllowUserSignalHandlers || !set_installed) {
2998      // Do not overwrite; user takes responsibility to forward to us.
2999      return;
3000    } else if (UseSignalChaining) {
3001      // save the old handler in jvm
3002      save_preinstalled_handler(sig, oldAct);
3003      // libjsig also interposes the sigaction() call below and saves the
3004      // old sigaction on it own.
3005    } else {
3006      fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3007                    "%#lx for signal %d.", (long)oldhand, sig));
3008    }
3009  }
3010
3011  struct sigaction sigAct;
3012  sigfillset(&(sigAct.sa_mask));
3013  sigAct.sa_handler = SIG_DFL;
3014  if (!set_installed) {
3015    sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3016  } else {
3017    sigAct.sa_sigaction = signalHandler;
3018    sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3019  }
3020  // Save flags, which are set by ours
3021  assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3022  sigflags[sig] = sigAct.sa_flags;
3023
3024  int ret = sigaction(sig, &sigAct, &oldAct);
3025  assert(ret == 0, "check");
3026
3027  void* oldhand2  = oldAct.sa_sigaction
3028                  ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3029                  : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3030  assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3031}
3032
3033// install signal handlers for signals that HotSpot needs to
3034// handle in order to support Java-level exception handling.
3035
3036void os::Bsd::install_signal_handlers() {
3037  if (!signal_handlers_are_installed) {
3038    signal_handlers_are_installed = true;
3039
3040    // signal-chaining
3041    typedef void (*signal_setting_t)();
3042    signal_setting_t begin_signal_setting = NULL;
3043    signal_setting_t end_signal_setting = NULL;
3044    begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3045                             dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3046    if (begin_signal_setting != NULL) {
3047      end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3048                             dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3049      get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3050                            dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3051      libjsig_is_loaded = true;
3052      assert(UseSignalChaining, "should enable signal-chaining");
3053    }
3054    if (libjsig_is_loaded) {
3055      // Tell libjsig jvm is setting signal handlers
3056      (*begin_signal_setting)();
3057    }
3058
3059    set_signal_handler(SIGSEGV, true);
3060    set_signal_handler(SIGPIPE, true);
3061    set_signal_handler(SIGBUS, true);
3062    set_signal_handler(SIGILL, true);
3063    set_signal_handler(SIGFPE, true);
3064    set_signal_handler(SIGXFSZ, true);
3065
3066#if defined(__APPLE__)
3067    // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3068    // signals caught and handled by the JVM. To work around this, we reset the mach task
3069    // signal handler that's placed on our process by CrashReporter. This disables
3070    // CrashReporter-based reporting.
3071    //
3072    // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3073    // on caught fatal signals.
3074    //
3075    // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3076    // handlers. By replacing the existing task exception handler, we disable gdb's mach
3077    // exception handling, while leaving the standard BSD signal handlers functional.
3078    kern_return_t kr;
3079    kr = task_set_exception_ports(mach_task_self(),
3080        EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3081        MACH_PORT_NULL,
3082        EXCEPTION_STATE_IDENTITY,
3083        MACHINE_THREAD_STATE);
3084
3085    assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3086#endif
3087
3088    if (libjsig_is_loaded) {
3089      // Tell libjsig jvm finishes setting signal handlers
3090      (*end_signal_setting)();
3091    }
3092
3093    // We don't activate signal checker if libjsig is in place, we trust ourselves
3094    // and if UserSignalHandler is installed all bets are off
3095    if (CheckJNICalls) {
3096      if (libjsig_is_loaded) {
3097        tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3098        check_signals = false;
3099      }
3100      if (AllowUserSignalHandlers) {
3101        tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3102        check_signals = false;
3103      }
3104    }
3105  }
3106}
3107
3108
3109/////
3110// glibc on Bsd platform uses non-documented flag
3111// to indicate, that some special sort of signal
3112// trampoline is used.
3113// We will never set this flag, and we should
3114// ignore this flag in our diagnostic
3115#ifdef SIGNIFICANT_SIGNAL_MASK
3116#undef SIGNIFICANT_SIGNAL_MASK
3117#endif
3118#define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3119
3120static const char* get_signal_handler_name(address handler,
3121                                           char* buf, int buflen) {
3122  int offset;
3123  bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3124  if (found) {
3125    // skip directory names
3126    const char *p1, *p2;
3127    p1 = buf;
3128    size_t len = strlen(os::file_separator());
3129    while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3130    jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3131  } else {
3132    jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3133  }
3134  return buf;
3135}
3136
3137static void print_signal_handler(outputStream* st, int sig,
3138                                 char* buf, size_t buflen) {
3139  struct sigaction sa;
3140
3141  sigaction(sig, NULL, &sa);
3142
3143  // See comment for SIGNIFICANT_SIGNAL_MASK define
3144  sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3145
3146  st->print("%s: ", os::exception_name(sig, buf, buflen));
3147
3148  address handler = (sa.sa_flags & SA_SIGINFO)
3149    ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3150    : CAST_FROM_FN_PTR(address, sa.sa_handler);
3151
3152  if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3153    st->print("SIG_DFL");
3154  } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3155    st->print("SIG_IGN");
3156  } else {
3157    st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3158  }
3159
3160  st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3161
3162  address rh = VMError::get_resetted_sighandler(sig);
3163  // May be, handler was resetted by VMError?
3164  if(rh != NULL) {
3165    handler = rh;
3166    sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3167  }
3168
3169  st->print(", sa_flags="   PTR32_FORMAT, sa.sa_flags);
3170
3171  // Check: is it our handler?
3172  if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3173     handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3174    // It is our signal handler
3175    // check for flags, reset system-used one!
3176    if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3177      st->print(
3178                ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3179                os::Bsd::get_our_sigflags(sig));
3180    }
3181  }
3182  st->cr();
3183}
3184
3185
3186#define DO_SIGNAL_CHECK(sig) \
3187  if (!sigismember(&check_signal_done, sig)) \
3188    os::Bsd::check_signal_handler(sig)
3189
3190// This method is a periodic task to check for misbehaving JNI applications
3191// under CheckJNI, we can add any periodic checks here
3192
3193void os::run_periodic_checks() {
3194
3195  if (check_signals == false) return;
3196
3197  // SEGV and BUS if overridden could potentially prevent
3198  // generation of hs*.log in the event of a crash, debugging
3199  // such a case can be very challenging, so we absolutely
3200  // check the following for a good measure:
3201  DO_SIGNAL_CHECK(SIGSEGV);
3202  DO_SIGNAL_CHECK(SIGILL);
3203  DO_SIGNAL_CHECK(SIGFPE);
3204  DO_SIGNAL_CHECK(SIGBUS);
3205  DO_SIGNAL_CHECK(SIGPIPE);
3206  DO_SIGNAL_CHECK(SIGXFSZ);
3207
3208
3209  // ReduceSignalUsage allows the user to override these handlers
3210  // see comments at the very top and jvm_solaris.h
3211  if (!ReduceSignalUsage) {
3212    DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3213    DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3214    DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3215    DO_SIGNAL_CHECK(BREAK_SIGNAL);
3216  }
3217
3218  DO_SIGNAL_CHECK(SR_signum);
3219  DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3220}
3221
3222typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3223
3224static os_sigaction_t os_sigaction = NULL;
3225
3226void os::Bsd::check_signal_handler(int sig) {
3227  char buf[O_BUFLEN];
3228  address jvmHandler = NULL;
3229
3230
3231  struct sigaction act;
3232  if (os_sigaction == NULL) {
3233    // only trust the default sigaction, in case it has been interposed
3234    os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3235    if (os_sigaction == NULL) return;
3236  }
3237
3238  os_sigaction(sig, (struct sigaction*)NULL, &act);
3239
3240
3241  act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3242
3243  address thisHandler = (act.sa_flags & SA_SIGINFO)
3244    ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3245    : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3246
3247
3248  switch(sig) {
3249  case SIGSEGV:
3250  case SIGBUS:
3251  case SIGFPE:
3252  case SIGPIPE:
3253  case SIGILL:
3254  case SIGXFSZ:
3255    jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3256    break;
3257
3258  case SHUTDOWN1_SIGNAL:
3259  case SHUTDOWN2_SIGNAL:
3260  case SHUTDOWN3_SIGNAL:
3261  case BREAK_SIGNAL:
3262    jvmHandler = (address)user_handler();
3263    break;
3264
3265  case INTERRUPT_SIGNAL:
3266    jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3267    break;
3268
3269  default:
3270    if (sig == SR_signum) {
3271      jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3272    } else {
3273      return;
3274    }
3275    break;
3276  }
3277
3278  if (thisHandler != jvmHandler) {
3279    tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3280    tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3281    tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3282    // No need to check this sig any longer
3283    sigaddset(&check_signal_done, sig);
3284  } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3285    tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3286    tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3287    tty->print_cr("  found:" PTR32_FORMAT, act.sa_flags);
3288    // No need to check this sig any longer
3289    sigaddset(&check_signal_done, sig);
3290  }
3291
3292  // Dump all the signal
3293  if (sigismember(&check_signal_done, sig)) {
3294    print_signal_handlers(tty, buf, O_BUFLEN);
3295  }
3296}
3297
3298extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3299
3300extern bool signal_name(int signo, char* buf, size_t len);
3301
3302const char* os::exception_name(int exception_code, char* buf, size_t size) {
3303  if (0 < exception_code && exception_code <= SIGRTMAX) {
3304    // signal
3305    if (!signal_name(exception_code, buf, size)) {
3306      jio_snprintf(buf, size, "SIG%d", exception_code);
3307    }
3308    return buf;
3309  } else {
3310    return NULL;
3311  }
3312}
3313
3314// this is called _before_ the most of global arguments have been parsed
3315void os::init(void) {
3316  char dummy;   /* used to get a guess on initial stack address */
3317//  first_hrtime = gethrtime();
3318
3319  // With BsdThreads the JavaMain thread pid (primordial thread)
3320  // is different than the pid of the java launcher thread.
3321  // So, on Bsd, the launcher thread pid is passed to the VM
3322  // via the sun.java.launcher.pid property.
3323  // Use this property instead of getpid() if it was correctly passed.
3324  // See bug 6351349.
3325  pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3326
3327  _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3328
3329  clock_tics_per_sec = CLK_TCK;
3330
3331  init_random(1234567);
3332
3333  ThreadCritical::initialize();
3334
3335  Bsd::set_page_size(getpagesize());
3336  if (Bsd::page_size() == -1) {
3337    fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3338                  strerror(errno)));
3339  }
3340  init_page_sizes((size_t) Bsd::page_size());
3341
3342  Bsd::initialize_system_info();
3343
3344  // main_thread points to the aboriginal thread
3345  Bsd::_main_thread = pthread_self();
3346
3347  Bsd::clock_init();
3348  initial_time_count = os::elapsed_counter();
3349
3350#ifdef __APPLE__
3351  // XXXDARWIN
3352  // Work around the unaligned VM callbacks in hotspot's
3353  // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3354  // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3355  // alignment when doing symbol lookup. To work around this, we force early
3356  // binding of all symbols now, thus binding when alignment is known-good.
3357  _dyld_bind_fully_image_containing_address((const void *) &os::init);
3358#endif
3359}
3360
3361// To install functions for atexit system call
3362extern "C" {
3363  static void perfMemory_exit_helper() {
3364    perfMemory_exit();
3365  }
3366}
3367
3368// this is called _after_ the global arguments have been parsed
3369jint os::init_2(void)
3370{
3371  // Allocate a single page and mark it as readable for safepoint polling
3372  address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3373  guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3374
3375  os::set_polling_page( polling_page );
3376
3377#ifndef PRODUCT
3378  if(Verbose && PrintMiscellaneous)
3379    tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3380#endif
3381
3382  if (!UseMembar) {
3383    address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3384    guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3385    os::set_memory_serialize_page( mem_serialize_page );
3386
3387#ifndef PRODUCT
3388    if(Verbose && PrintMiscellaneous)
3389      tty->print("[Memory Serialize  Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3390#endif
3391  }
3392
3393  os::large_page_init();
3394
3395  // initialize suspend/resume support - must do this before signal_sets_init()
3396  if (SR_initialize() != 0) {
3397    perror("SR_initialize failed");
3398    return JNI_ERR;
3399  }
3400
3401  Bsd::signal_sets_init();
3402  Bsd::install_signal_handlers();
3403
3404  // Check minimum allowable stack size for thread creation and to initialize
3405  // the java system classes, including StackOverflowError - depends on page
3406  // size.  Add a page for compiler2 recursion in main thread.
3407  // Add in 2*BytesPerWord times page size to account for VM stack during
3408  // class initialization depending on 32 or 64 bit VM.
3409  os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3410            (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3411                    2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3412
3413  size_t threadStackSizeInBytes = ThreadStackSize * K;
3414  if (threadStackSizeInBytes != 0 &&
3415      threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3416        tty->print_cr("\nThe stack size specified is too small, "
3417                      "Specify at least %dk",
3418                      os::Bsd::min_stack_allowed/ K);
3419        return JNI_ERR;
3420  }
3421
3422  // Make the stack size a multiple of the page size so that
3423  // the yellow/red zones can be guarded.
3424  JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3425        vm_page_size()));
3426
3427  if (MaxFDLimit) {
3428    // set the number of file descriptors to max. print out error
3429    // if getrlimit/setrlimit fails but continue regardless.
3430    struct rlimit nbr_files;
3431    int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3432    if (status != 0) {
3433      if (PrintMiscellaneous && (Verbose || WizardMode))
3434        perror("os::init_2 getrlimit failed");
3435    } else {
3436      nbr_files.rlim_cur = nbr_files.rlim_max;
3437
3438#ifdef __APPLE__
3439      // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3440      // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3441      // be used instead
3442      nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3443#endif
3444
3445      status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3446      if (status != 0) {
3447        if (PrintMiscellaneous && (Verbose || WizardMode))
3448          perror("os::init_2 setrlimit failed");
3449      }
3450    }
3451  }
3452
3453  // at-exit methods are called in the reverse order of their registration.
3454  // atexit functions are called on return from main or as a result of a
3455  // call to exit(3C). There can be only 32 of these functions registered
3456  // and atexit() does not set errno.
3457
3458  if (PerfAllowAtExitRegistration) {
3459    // only register atexit functions if PerfAllowAtExitRegistration is set.
3460    // atexit functions can be delayed until process exit time, which
3461    // can be problematic for embedded VM situations. Embedded VMs should
3462    // call DestroyJavaVM() to assure that VM resources are released.
3463
3464    // note: perfMemory_exit_helper atexit function may be removed in
3465    // the future if the appropriate cleanup code can be added to the
3466    // VM_Exit VMOperation's doit method.
3467    if (atexit(perfMemory_exit_helper) != 0) {
3468      warning("os::init2 atexit(perfMemory_exit_helper) failed");
3469    }
3470  }
3471
3472  // initialize thread priority policy
3473  prio_init();
3474
3475#ifdef __APPLE__
3476  // dynamically link to objective c gc registration
3477  void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3478  if (handleLibObjc != NULL) {
3479    objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3480  }
3481#endif
3482
3483  return JNI_OK;
3484}
3485
3486// this is called at the end of vm_initialization
3487void os::init_3(void) { }
3488
3489// Mark the polling page as unreadable
3490void os::make_polling_page_unreadable(void) {
3491  if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3492    fatal("Could not disable polling page");
3493};
3494
3495// Mark the polling page as readable
3496void os::make_polling_page_readable(void) {
3497  if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3498    fatal("Could not enable polling page");
3499  }
3500};
3501
3502int os::active_processor_count() {
3503  return _processor_count;
3504}
3505
3506void os::set_native_thread_name(const char *name) {
3507#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3508  // This is only supported in Snow Leopard and beyond
3509  if (name != NULL) {
3510    // Add a "Java: " prefix to the name
3511    char buf[MAXTHREADNAMESIZE];
3512    snprintf(buf, sizeof(buf), "Java: %s", name);
3513    pthread_setname_np(buf);
3514  }
3515#endif
3516}
3517
3518bool os::distribute_processes(uint length, uint* distribution) {
3519  // Not yet implemented.
3520  return false;
3521}
3522
3523bool os::bind_to_processor(uint processor_id) {
3524  // Not yet implemented.
3525  return false;
3526}
3527
3528///
3529
3530// Suspends the target using the signal mechanism and then grabs the PC before
3531// resuming the target. Used by the flat-profiler only
3532ExtendedPC os::get_thread_pc(Thread* thread) {
3533  // Make sure that it is called by the watcher for the VMThread
3534  assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3535  assert(thread->is_VM_thread(), "Can only be called for VMThread");
3536
3537  ExtendedPC epc;
3538
3539  OSThread* osthread = thread->osthread();
3540  if (do_suspend(osthread)) {
3541    if (osthread->ucontext() != NULL) {
3542      epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
3543    } else {
3544      // NULL context is unexpected, double-check this is the VMThread
3545      guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3546    }
3547    do_resume(osthread);
3548  }
3549  // failure means pthread_kill failed for some reason - arguably this is
3550  // a fatal problem, but such problems are ignored elsewhere
3551
3552  return epc;
3553}
3554
3555int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3556{
3557  return pthread_cond_timedwait(_cond, _mutex, _abstime);
3558}
3559
3560////////////////////////////////////////////////////////////////////////////////
3561// debug support
3562
3563static address same_page(address x, address y) {
3564  int page_bits = -os::vm_page_size();
3565  if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
3566    return x;
3567  else if (x > y)
3568    return (address)(intptr_t(y) | ~page_bits) + 1;
3569  else
3570    return (address)(intptr_t(y) & page_bits);
3571}
3572
3573bool os::find(address addr, outputStream* st) {
3574  Dl_info dlinfo;
3575  memset(&dlinfo, 0, sizeof(dlinfo));
3576  if (dladdr(addr, &dlinfo)) {
3577    st->print(PTR_FORMAT ": ", addr);
3578    if (dlinfo.dli_sname != NULL) {
3579      st->print("%s+%#x", dlinfo.dli_sname,
3580                 addr - (intptr_t)dlinfo.dli_saddr);
3581    } else if (dlinfo.dli_fname) {
3582      st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3583    } else {
3584      st->print("<absolute address>");
3585    }
3586    if (dlinfo.dli_fname) {
3587      st->print(" in %s", dlinfo.dli_fname);
3588    }
3589    if (dlinfo.dli_fbase) {
3590      st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3591    }
3592    st->cr();
3593
3594    if (Verbose) {
3595      // decode some bytes around the PC
3596      address begin = same_page(addr-40, addr);
3597      address end   = same_page(addr+40, addr);
3598      address       lowest = (address) dlinfo.dli_sname;
3599      if (!lowest)  lowest = (address) dlinfo.dli_fbase;
3600      if (begin < lowest)  begin = lowest;
3601      Dl_info dlinfo2;
3602      if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
3603          && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3604        end = (address) dlinfo2.dli_saddr;
3605      Disassembler::decode(begin, end, st);
3606    }
3607    return true;
3608  }
3609  return false;
3610}
3611
3612////////////////////////////////////////////////////////////////////////////////
3613// misc
3614
3615// This does not do anything on Bsd. This is basically a hook for being
3616// able to use structured exception handling (thread-local exception filters)
3617// on, e.g., Win32.
3618void
3619os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3620                         JavaCallArguments* args, Thread* thread) {
3621  f(value, method, args, thread);
3622}
3623
3624void os::print_statistics() {
3625}
3626
3627int os::message_box(const char* title, const char* message) {
3628  int i;
3629  fdStream err(defaultStream::error_fd());
3630  for (i = 0; i < 78; i++) err.print_raw("=");
3631  err.cr();
3632  err.print_raw_cr(title);
3633  for (i = 0; i < 78; i++) err.print_raw("-");
3634  err.cr();
3635  err.print_raw_cr(message);
3636  for (i = 0; i < 78; i++) err.print_raw("=");
3637  err.cr();
3638
3639  char buf[16];
3640  // Prevent process from exiting upon "read error" without consuming all CPU
3641  while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3642
3643  return buf[0] == 'y' || buf[0] == 'Y';
3644}
3645
3646int os::stat(const char *path, struct stat *sbuf) {
3647  char pathbuf[MAX_PATH];
3648  if (strlen(path) > MAX_PATH - 1) {
3649    errno = ENAMETOOLONG;
3650    return -1;
3651  }
3652  os::native_path(strcpy(pathbuf, path));
3653  return ::stat(pathbuf, sbuf);
3654}
3655
3656bool os::check_heap(bool force) {
3657  return true;
3658}
3659
3660int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3661  return ::vsnprintf(buf, count, format, args);
3662}
3663
3664// Is a (classpath) directory empty?
3665bool os::dir_is_empty(const char* path) {
3666  DIR *dir = NULL;
3667  struct dirent *ptr;
3668
3669  dir = opendir(path);
3670  if (dir == NULL) return true;
3671
3672  /* Scan the directory */
3673  bool result = true;
3674  char buf[sizeof(struct dirent) + MAX_PATH];
3675  while (result && (ptr = ::readdir(dir)) != NULL) {
3676    if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3677      result = false;
3678    }
3679  }
3680  closedir(dir);
3681  return result;
3682}
3683
3684// This code originates from JDK's sysOpen and open64_w
3685// from src/solaris/hpi/src/system_md.c
3686
3687#ifndef O_DELETE
3688#define O_DELETE 0x10000
3689#endif
3690
3691// Open a file. Unlink the file immediately after open returns
3692// if the specified oflag has the O_DELETE flag set.
3693// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3694
3695int os::open(const char *path, int oflag, int mode) {
3696
3697  if (strlen(path) > MAX_PATH - 1) {
3698    errno = ENAMETOOLONG;
3699    return -1;
3700  }
3701  int fd;
3702  int o_delete = (oflag & O_DELETE);
3703  oflag = oflag & ~O_DELETE;
3704
3705  fd = ::open(path, oflag, mode);
3706  if (fd == -1) return -1;
3707
3708  //If the open succeeded, the file might still be a directory
3709  {
3710    struct stat buf;
3711    int ret = ::fstat(fd, &buf);
3712    int st_mode = buf.st_mode;
3713
3714    if (ret != -1) {
3715      if ((st_mode & S_IFMT) == S_IFDIR) {
3716        errno = EISDIR;
3717        ::close(fd);
3718        return -1;
3719      }
3720    } else {
3721      ::close(fd);
3722      return -1;
3723    }
3724  }
3725
3726    /*
3727     * All file descriptors that are opened in the JVM and not
3728     * specifically destined for a subprocess should have the
3729     * close-on-exec flag set.  If we don't set it, then careless 3rd
3730     * party native code might fork and exec without closing all
3731     * appropriate file descriptors (e.g. as we do in closeDescriptors in
3732     * UNIXProcess.c), and this in turn might:
3733     *
3734     * - cause end-of-file to fail to be detected on some file
3735     *   descriptors, resulting in mysterious hangs, or
3736     *
3737     * - might cause an fopen in the subprocess to fail on a system
3738     *   suffering from bug 1085341.
3739     *
3740     * (Yes, the default setting of the close-on-exec flag is a Unix
3741     * design flaw)
3742     *
3743     * See:
3744     * 1085341: 32-bit stdio routines should support file descriptors >255
3745     * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3746     * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3747     */
3748#ifdef FD_CLOEXEC
3749    {
3750        int flags = ::fcntl(fd, F_GETFD);
3751        if (flags != -1)
3752            ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3753    }
3754#endif
3755
3756  if (o_delete != 0) {
3757    ::unlink(path);
3758  }
3759  return fd;
3760}
3761
3762
3763// create binary file, rewriting existing file if required
3764int os::create_binary_file(const char* path, bool rewrite_existing) {
3765  int oflags = O_WRONLY | O_CREAT;
3766  if (!rewrite_existing) {
3767    oflags |= O_EXCL;
3768  }
3769  return ::open(path, oflags, S_IREAD | S_IWRITE);
3770}
3771
3772// return current position of file pointer
3773jlong os::current_file_offset(int fd) {
3774  return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3775}
3776
3777// move file pointer to the specified offset
3778jlong os::seek_to_file_offset(int fd, jlong offset) {
3779  return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3780}
3781
3782// This code originates from JDK's sysAvailable
3783// from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3784
3785int os::available(int fd, jlong *bytes) {
3786  jlong cur, end;
3787  int mode;
3788  struct stat buf;
3789
3790  if (::fstat(fd, &buf) >= 0) {
3791    mode = buf.st_mode;
3792    if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3793      /*
3794      * XXX: is the following call interruptible? If so, this might
3795      * need to go through the INTERRUPT_IO() wrapper as for other
3796      * blocking, interruptible calls in this file.
3797      */
3798      int n;
3799      if (::ioctl(fd, FIONREAD, &n) >= 0) {
3800        *bytes = n;
3801        return 1;
3802      }
3803    }
3804  }
3805  if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3806    return 0;
3807  } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3808    return 0;
3809  } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3810    return 0;
3811  }
3812  *bytes = end - cur;
3813  return 1;
3814}
3815
3816int os::socket_available(int fd, jint *pbytes) {
3817   if (fd < 0)
3818     return OS_OK;
3819
3820   int ret;
3821
3822   RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3823
3824   //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3825   // is expected to return 0 on failure and 1 on success to the jdk.
3826
3827   return (ret == OS_ERR) ? 0 : 1;
3828}
3829
3830// Map a block of memory.
3831char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3832                     char *addr, size_t bytes, bool read_only,
3833                     bool allow_exec) {
3834  int prot;
3835  int flags;
3836
3837  if (read_only) {
3838    prot = PROT_READ;
3839    flags = MAP_SHARED;
3840  } else {
3841    prot = PROT_READ | PROT_WRITE;
3842    flags = MAP_PRIVATE;
3843  }
3844
3845  if (allow_exec) {
3846    prot |= PROT_EXEC;
3847  }
3848
3849  if (addr != NULL) {
3850    flags |= MAP_FIXED;
3851  }
3852
3853  char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3854                                     fd, file_offset);
3855  if (mapped_address == MAP_FAILED) {
3856    return NULL;
3857  }
3858  return mapped_address;
3859}
3860
3861
3862// Remap a block of memory.
3863char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3864                       char *addr, size_t bytes, bool read_only,
3865                       bool allow_exec) {
3866  // same as map_memory() on this OS
3867  return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3868                        allow_exec);
3869}
3870
3871
3872// Unmap a block of memory.
3873bool os::pd_unmap_memory(char* addr, size_t bytes) {
3874  return munmap(addr, bytes) == 0;
3875}
3876
3877// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3878// are used by JVM M&M and JVMTI to get user+sys or user CPU time
3879// of a thread.
3880//
3881// current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3882// the fast estimate available on the platform.
3883
3884jlong os::current_thread_cpu_time() {
3885#ifdef __APPLE__
3886  return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3887#endif
3888}
3889
3890jlong os::thread_cpu_time(Thread* thread) {
3891}
3892
3893jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3894#ifdef __APPLE__
3895  return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3896#endif
3897}
3898
3899jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3900#ifdef __APPLE__
3901  struct thread_basic_info tinfo;
3902  mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3903  kern_return_t kr;
3904  thread_t mach_thread;
3905
3906  mach_thread = thread->osthread()->thread_id();
3907  kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3908  if (kr != KERN_SUCCESS)
3909    return -1;
3910
3911  if (user_sys_cpu_time) {
3912    jlong nanos;
3913    nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3914    nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3915    return nanos;
3916  } else {
3917    return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3918  }
3919#endif
3920}
3921
3922
3923void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3924  info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3925  info_ptr->may_skip_backward = false;     // elapsed time not wall time
3926  info_ptr->may_skip_forward = false;      // elapsed time not wall time
3927  info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3928}
3929
3930void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3931  info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
3932  info_ptr->may_skip_backward = false;     // elapsed time not wall time
3933  info_ptr->may_skip_forward = false;      // elapsed time not wall time
3934  info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
3935}
3936
3937bool os::is_thread_cpu_time_supported() {
3938#ifdef __APPLE__
3939  return true;
3940#else
3941  return false;
3942#endif
3943}
3944
3945// System loadavg support.  Returns -1 if load average cannot be obtained.
3946// Bsd doesn't yet have a (official) notion of processor sets,
3947// so just return the system wide load average.
3948int os::loadavg(double loadavg[], int nelem) {
3949  return ::getloadavg(loadavg, nelem);
3950}
3951
3952void os::pause() {
3953  char filename[MAX_PATH];
3954  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3955    jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3956  } else {
3957    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3958  }
3959
3960  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3961  if (fd != -1) {
3962    struct stat buf;
3963    ::close(fd);
3964    while (::stat(filename, &buf) == 0) {
3965      (void)::poll(NULL, 0, 100);
3966    }
3967  } else {
3968    jio_fprintf(stderr,
3969      "Could not open pause file '%s', continuing immediately.\n", filename);
3970  }
3971}
3972
3973
3974// Refer to the comments in os_solaris.cpp park-unpark.
3975//
3976// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
3977// hang indefinitely.  For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
3978// For specifics regarding the bug see GLIBC BUGID 261237 :
3979//    http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
3980// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
3981// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
3982// is used.  (The simple C test-case provided in the GLIBC bug report manifests the
3983// hang).  The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
3984// and monitorenter when we're using 1-0 locking.  All those operations may result in
3985// calls to pthread_cond_timedwait().  Using LD_ASSUME_KERNEL to use an older version
3986// of libpthread avoids the problem, but isn't practical.
3987//
3988// Possible remedies:
3989//
3990// 1.   Establish a minimum relative wait time.  50 to 100 msecs seems to work.
3991//      This is palliative and probabilistic, however.  If the thread is preempted
3992//      between the call to compute_abstime() and pthread_cond_timedwait(), more
3993//      than the minimum period may have passed, and the abstime may be stale (in the
3994//      past) resultin in a hang.   Using this technique reduces the odds of a hang
3995//      but the JVM is still vulnerable, particularly on heavily loaded systems.
3996//
3997// 2.   Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
3998//      of the usual flag-condvar-mutex idiom.  The write side of the pipe is set
3999//      NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4000//      reduces to poll()+read().  This works well, but consumes 2 FDs per extant
4001//      thread.
4002//
4003// 3.   Embargo pthread_cond_timedwait() and implement a native "chron" thread
4004//      that manages timeouts.  We'd emulate pthread_cond_timedwait() by enqueuing
4005//      a timeout request to the chron thread and then blocking via pthread_cond_wait().
4006//      This also works well.  In fact it avoids kernel-level scalability impediments
4007//      on certain platforms that don't handle lots of active pthread_cond_timedwait()
4008//      timers in a graceful fashion.
4009//
4010// 4.   When the abstime value is in the past it appears that control returns
4011//      correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4012//      Subsequent timedwait/wait calls may hang indefinitely.  Given that, we
4013//      can avoid the problem by reinitializing the condvar -- by cond_destroy()
4014//      followed by cond_init() -- after all calls to pthread_cond_timedwait().
4015//      It may be possible to avoid reinitialization by checking the return
4016//      value from pthread_cond_timedwait().  In addition to reinitializing the
4017//      condvar we must establish the invariant that cond_signal() is only called
4018//      within critical sections protected by the adjunct mutex.  This prevents
4019//      cond_signal() from "seeing" a condvar that's in the midst of being
4020//      reinitialized or that is corrupt.  Sadly, this invariant obviates the
4021//      desirable signal-after-unlock optimization that avoids futile context switching.
4022//
4023//      I'm also concerned that some versions of NTPL might allocate an auxilliary
4024//      structure when a condvar is used or initialized.  cond_destroy()  would
4025//      release the helper structure.  Our reinitialize-after-timedwait fix
4026//      put excessive stress on malloc/free and locks protecting the c-heap.
4027//
4028// We currently use (4).  See the WorkAroundNTPLTimedWaitHang flag.
4029// It may be possible to refine (4) by checking the kernel and NTPL verisons
4030// and only enabling the work-around for vulnerable environments.
4031
4032// utility to compute the abstime argument to timedwait:
4033// millis is the relative timeout time
4034// abstime will be the absolute timeout time
4035// TODO: replace compute_abstime() with unpackTime()
4036
4037static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4038  if (millis < 0)  millis = 0;
4039  struct timeval now;
4040  int status = gettimeofday(&now, NULL);
4041  assert(status == 0, "gettimeofday");
4042  jlong seconds = millis / 1000;
4043  millis %= 1000;
4044  if (seconds > 50000000) { // see man cond_timedwait(3T)
4045    seconds = 50000000;
4046  }
4047  abstime->tv_sec = now.tv_sec  + seconds;
4048  long       usec = now.tv_usec + millis * 1000;
4049  if (usec >= 1000000) {
4050    abstime->tv_sec += 1;
4051    usec -= 1000000;
4052  }
4053  abstime->tv_nsec = usec * 1000;
4054  return abstime;
4055}
4056
4057
4058// Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4059// Conceptually TryPark() should be equivalent to park(0).
4060
4061int os::PlatformEvent::TryPark() {
4062  for (;;) {
4063    const int v = _Event ;
4064    guarantee ((v == 0) || (v == 1), "invariant") ;
4065    if (Atomic::cmpxchg (0, &_Event, v) == v) return v  ;
4066  }
4067}
4068
4069void os::PlatformEvent::park() {       // AKA "down()"
4070  // Invariant: Only the thread associated with the Event/PlatformEvent
4071  // may call park().
4072  // TODO: assert that _Assoc != NULL or _Assoc == Self
4073  int v ;
4074  for (;;) {
4075      v = _Event ;
4076      if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4077  }
4078  guarantee (v >= 0, "invariant") ;
4079  if (v == 0) {
4080     // Do this the hard way by blocking ...
4081     int status = pthread_mutex_lock(_mutex);
4082     assert_status(status == 0, status, "mutex_lock");
4083     guarantee (_nParked == 0, "invariant") ;
4084     ++ _nParked ;
4085     while (_Event < 0) {
4086        status = pthread_cond_wait(_cond, _mutex);
4087        // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4088        // Treat this the same as if the wait was interrupted
4089        if (status == ETIMEDOUT) { status = EINTR; }
4090        assert_status(status == 0 || status == EINTR, status, "cond_wait");
4091     }
4092     -- _nParked ;
4093
4094    // In theory we could move the ST of 0 into _Event past the unlock(),
4095    // but then we'd need a MEMBAR after the ST.
4096    _Event = 0 ;
4097     status = pthread_mutex_unlock(_mutex);
4098     assert_status(status == 0, status, "mutex_unlock");
4099  }
4100  guarantee (_Event >= 0, "invariant") ;
4101}
4102
4103int os::PlatformEvent::park(jlong millis) {
4104  guarantee (_nParked == 0, "invariant") ;
4105
4106  int v ;
4107  for (;;) {
4108      v = _Event ;
4109      if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4110  }
4111  guarantee (v >= 0, "invariant") ;
4112  if (v != 0) return OS_OK ;
4113
4114  // We do this the hard way, by blocking the thread.
4115  // Consider enforcing a minimum timeout value.
4116  struct timespec abst;
4117  compute_abstime(&abst, millis);
4118
4119  int ret = OS_TIMEOUT;
4120  int status = pthread_mutex_lock(_mutex);
4121  assert_status(status == 0, status, "mutex_lock");
4122  guarantee (_nParked == 0, "invariant") ;
4123  ++_nParked ;
4124
4125  // Object.wait(timo) will return because of
4126  // (a) notification
4127  // (b) timeout
4128  // (c) thread.interrupt
4129  //
4130  // Thread.interrupt and object.notify{All} both call Event::set.
4131  // That is, we treat thread.interrupt as a special case of notification.
4132  // The underlying Solaris implementation, cond_timedwait, admits
4133  // spurious/premature wakeups, but the JLS/JVM spec prevents the
4134  // JVM from making those visible to Java code.  As such, we must
4135  // filter out spurious wakeups.  We assume all ETIME returns are valid.
4136  //
4137  // TODO: properly differentiate simultaneous notify+interrupt.
4138  // In that case, we should propagate the notify to another waiter.
4139
4140  while (_Event < 0) {
4141    status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4142    if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4143      pthread_cond_destroy (_cond);
4144      pthread_cond_init (_cond, NULL) ;
4145    }
4146    assert_status(status == 0 || status == EINTR ||
4147                  status == ETIMEDOUT,
4148                  status, "cond_timedwait");
4149    if (!FilterSpuriousWakeups) break ;                 // previous semantics
4150    if (status == ETIMEDOUT) break ;
4151    // We consume and ignore EINTR and spurious wakeups.
4152  }
4153  --_nParked ;
4154  if (_Event >= 0) {
4155     ret = OS_OK;
4156  }
4157  _Event = 0 ;
4158  status = pthread_mutex_unlock(_mutex);
4159  assert_status(status == 0, status, "mutex_unlock");
4160  assert (_nParked == 0, "invariant") ;
4161  return ret;
4162}
4163
4164void os::PlatformEvent::unpark() {
4165  int v, AnyWaiters ;
4166  for (;;) {
4167      v = _Event ;
4168      if (v > 0) {
4169         // The LD of _Event could have reordered or be satisfied
4170         // by a read-aside from this processor's write buffer.
4171         // To avoid problems execute a barrier and then
4172         // ratify the value.
4173         OrderAccess::fence() ;
4174         if (_Event == v) return ;
4175         continue ;
4176      }
4177      if (Atomic::cmpxchg (v+1, &_Event, v) == v) break ;
4178  }
4179  if (v < 0) {
4180     // Wait for the thread associated with the event to vacate
4181     int status = pthread_mutex_lock(_mutex);
4182     assert_status(status == 0, status, "mutex_lock");
4183     AnyWaiters = _nParked ;
4184     assert (AnyWaiters == 0 || AnyWaiters == 1, "invariant") ;
4185     if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4186        AnyWaiters = 0 ;
4187        pthread_cond_signal (_cond);
4188     }
4189     status = pthread_mutex_unlock(_mutex);
4190     assert_status(status == 0, status, "mutex_unlock");
4191     if (AnyWaiters != 0) {
4192        status = pthread_cond_signal(_cond);
4193        assert_status(status == 0, status, "cond_signal");
4194     }
4195  }
4196
4197  // Note that we signal() _after dropping the lock for "immortal" Events.
4198  // This is safe and avoids a common class of  futile wakeups.  In rare
4199  // circumstances this can cause a thread to return prematurely from
4200  // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4201  // simply re-test the condition and re-park itself.
4202}
4203
4204
4205// JSR166
4206// -------------------------------------------------------
4207
4208/*
4209 * The solaris and bsd implementations of park/unpark are fairly
4210 * conservative for now, but can be improved. They currently use a
4211 * mutex/condvar pair, plus a a count.
4212 * Park decrements count if > 0, else does a condvar wait.  Unpark
4213 * sets count to 1 and signals condvar.  Only one thread ever waits
4214 * on the condvar. Contention seen when trying to park implies that someone
4215 * is unparking you, so don't wait. And spurious returns are fine, so there
4216 * is no need to track notifications.
4217 */
4218
4219#define MAX_SECS 100000000
4220/*
4221 * This code is common to bsd and solaris and will be moved to a
4222 * common place in dolphin.
4223 *
4224 * The passed in time value is either a relative time in nanoseconds
4225 * or an absolute time in milliseconds. Either way it has to be unpacked
4226 * into suitable seconds and nanoseconds components and stored in the
4227 * given timespec structure.
4228 * Given time is a 64-bit value and the time_t used in the timespec is only
4229 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4230 * overflow if times way in the future are given. Further on Solaris versions
4231 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4232 * number of seconds, in abstime, is less than current_time  + 100,000,000.
4233 * As it will be 28 years before "now + 100000000" will overflow we can
4234 * ignore overflow and just impose a hard-limit on seconds using the value
4235 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4236 * years from "now".
4237 */
4238
4239static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4240  assert (time > 0, "convertTime");
4241
4242  struct timeval now;
4243  int status = gettimeofday(&now, NULL);
4244  assert(status == 0, "gettimeofday");
4245
4246  time_t max_secs = now.tv_sec + MAX_SECS;
4247
4248  if (isAbsolute) {
4249    jlong secs = time / 1000;
4250    if (secs > max_secs) {
4251      absTime->tv_sec = max_secs;
4252    }
4253    else {
4254      absTime->tv_sec = secs;
4255    }
4256    absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4257  }
4258  else {
4259    jlong secs = time / NANOSECS_PER_SEC;
4260    if (secs >= MAX_SECS) {
4261      absTime->tv_sec = max_secs;
4262      absTime->tv_nsec = 0;
4263    }
4264    else {
4265      absTime->tv_sec = now.tv_sec + secs;
4266      absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4267      if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4268        absTime->tv_nsec -= NANOSECS_PER_SEC;
4269        ++absTime->tv_sec; // note: this must be <= max_secs
4270      }
4271    }
4272  }
4273  assert(absTime->tv_sec >= 0, "tv_sec < 0");
4274  assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4275  assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4276  assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4277}
4278
4279void Parker::park(bool isAbsolute, jlong time) {
4280  // Optional fast-path check:
4281  // Return immediately if a permit is available.
4282  if (_counter > 0) {
4283      _counter = 0 ;
4284      OrderAccess::fence();
4285      return ;
4286  }
4287
4288  Thread* thread = Thread::current();
4289  assert(thread->is_Java_thread(), "Must be JavaThread");
4290  JavaThread *jt = (JavaThread *)thread;
4291
4292  // Optional optimization -- avoid state transitions if there's an interrupt pending.
4293  // Check interrupt before trying to wait
4294  if (Thread::is_interrupted(thread, false)) {
4295    return;
4296  }
4297
4298  // Next, demultiplex/decode time arguments
4299  struct timespec absTime;
4300  if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4301    return;
4302  }
4303  if (time > 0) {
4304    unpackTime(&absTime, isAbsolute, time);
4305  }
4306
4307
4308  // Enter safepoint region
4309  // Beware of deadlocks such as 6317397.
4310  // The per-thread Parker:: mutex is a classic leaf-lock.
4311  // In particular a thread must never block on the Threads_lock while
4312  // holding the Parker:: mutex.  If safepoints are pending both the
4313  // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4314  ThreadBlockInVM tbivm(jt);
4315
4316  // Don't wait if cannot get lock since interference arises from
4317  // unblocking.  Also. check interrupt before trying wait
4318  if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4319    return;
4320  }
4321
4322  int status ;
4323  if (_counter > 0)  { // no wait needed
4324    _counter = 0;
4325    status = pthread_mutex_unlock(_mutex);
4326    assert (status == 0, "invariant") ;
4327    OrderAccess::fence();
4328    return;
4329  }
4330
4331#ifdef ASSERT
4332  // Don't catch signals while blocked; let the running threads have the signals.
4333  // (This allows a debugger to break into the running thread.)
4334  sigset_t oldsigs;
4335  sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4336  pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4337#endif
4338
4339  OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4340  jt->set_suspend_equivalent();
4341  // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4342
4343  if (time == 0) {
4344    status = pthread_cond_wait (_cond, _mutex) ;
4345  } else {
4346    status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4347    if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4348      pthread_cond_destroy (_cond) ;
4349      pthread_cond_init    (_cond, NULL);
4350    }
4351  }
4352  assert_status(status == 0 || status == EINTR ||
4353                status == ETIMEDOUT,
4354                status, "cond_timedwait");
4355
4356#ifdef ASSERT
4357  pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4358#endif
4359
4360  _counter = 0 ;
4361  status = pthread_mutex_unlock(_mutex) ;
4362  assert_status(status == 0, status, "invariant") ;
4363  // If externally suspended while waiting, re-suspend
4364  if (jt->handle_special_suspend_equivalent_condition()) {
4365    jt->java_suspend_self();
4366  }
4367
4368  OrderAccess::fence();
4369}
4370
4371void Parker::unpark() {
4372  int s, status ;
4373  status = pthread_mutex_lock(_mutex);
4374  assert (status == 0, "invariant") ;
4375  s = _counter;
4376  _counter = 1;
4377  if (s < 1) {
4378     if (WorkAroundNPTLTimedWaitHang) {
4379        status = pthread_cond_signal (_cond) ;
4380        assert (status == 0, "invariant") ;
4381        status = pthread_mutex_unlock(_mutex);
4382        assert (status == 0, "invariant") ;
4383     } else {
4384        status = pthread_mutex_unlock(_mutex);
4385        assert (status == 0, "invariant") ;
4386        status = pthread_cond_signal (_cond) ;
4387        assert (status == 0, "invariant") ;
4388     }
4389  } else {
4390    pthread_mutex_unlock(_mutex);
4391    assert (status == 0, "invariant") ;
4392  }
4393}
4394
4395
4396/* Darwin has no "environ" in a dynamic library. */
4397#ifdef __APPLE__
4398#include <crt_externs.h>
4399#define environ (*_NSGetEnviron())
4400#else
4401extern char** environ;
4402#endif
4403
4404// Run the specified command in a separate process. Return its exit value,
4405// or -1 on failure (e.g. can't fork a new process).
4406// Unlike system(), this function can be called from signal handler. It
4407// doesn't block SIGINT et al.
4408int os::fork_and_exec(char* cmd) {
4409  const char * argv[4] = {"sh", "-c", cmd, NULL};
4410
4411  // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4412  // pthread_atfork handlers and reset pthread library. All we need is a
4413  // separate process to execve. Make a direct syscall to fork process.
4414  // On IA64 there's no fork syscall, we have to use fork() and hope for
4415  // the best...
4416  pid_t pid = fork();
4417
4418  if (pid < 0) {
4419    // fork failed
4420    return -1;
4421
4422  } else if (pid == 0) {
4423    // child process
4424
4425    // execve() in BsdThreads will call pthread_kill_other_threads_np()
4426    // first to kill every thread on the thread list. Because this list is
4427    // not reset by fork() (see notes above), execve() will instead kill
4428    // every thread in the parent process. We know this is the only thread
4429    // in the new process, so make a system call directly.
4430    // IA64 should use normal execve() from glibc to match the glibc fork()
4431    // above.
4432    execve("/bin/sh", (char* const*)argv, environ);
4433
4434    // execve failed
4435    _exit(-1);
4436
4437  } else  {
4438    // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4439    // care about the actual exit code, for now.
4440
4441    int status;
4442
4443    // Wait for the child process to exit.  This returns immediately if
4444    // the child has already exited. */
4445    while (waitpid(pid, &status, 0) < 0) {
4446        switch (errno) {
4447        case ECHILD: return 0;
4448        case EINTR: break;
4449        default: return -1;
4450        }
4451    }
4452
4453    if (WIFEXITED(status)) {
4454       // The child exited normally; get its exit code.
4455       return WEXITSTATUS(status);
4456    } else if (WIFSIGNALED(status)) {
4457       // The child exited because of a signal
4458       // The best value to return is 0x80 + signal number,
4459       // because that is what all Unix shells do, and because
4460       // it allows callers to distinguish between process exit and
4461       // process death by signal.
4462       return 0x80 + WTERMSIG(status);
4463    } else {
4464       // Unknown exit code; pass it through
4465       return status;
4466    }
4467  }
4468}
4469
4470// is_headless_jre()
4471//
4472// Test for the existence of xawt/libmawt.so or libawt_xawt.so
4473// in order to report if we are running in a headless jre
4474//
4475// Since JDK8 xawt/libmawt.so was moved into the same directory
4476// as libawt.so, and renamed libawt_xawt.so
4477//
4478bool os::is_headless_jre() {
4479    struct stat statbuf;
4480    char buf[MAXPATHLEN];
4481    char libmawtpath[MAXPATHLEN];
4482    const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
4483    const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4484    char *p;
4485
4486    // Get path to libjvm.so
4487    os::jvm_path(buf, sizeof(buf));
4488
4489    // Get rid of libjvm.so
4490    p = strrchr(buf, '/');
4491    if (p == NULL) return false;
4492    else *p = '\0';
4493
4494    // Get rid of client or server
4495    p = strrchr(buf, '/');
4496    if (p == NULL) return false;
4497    else *p = '\0';
4498
4499    // check xawt/libmawt.so
4500    strcpy(libmawtpath, buf);
4501    strcat(libmawtpath, xawtstr);
4502    if (::stat(libmawtpath, &statbuf) == 0) return false;
4503
4504    // check libawt_xawt.so
4505    strcpy(libmawtpath, buf);
4506    strcat(libmawtpath, new_xawtstr);
4507    if (::stat(libmawtpath, &statbuf) == 0) return false;
4508
4509    return true;
4510}
4511
4512// Get the default path to the core file
4513// Returns the length of the string
4514int os::get_core_path(char* buffer, size_t bufferSize) {
4515  int n = jio_snprintf(buffer, bufferSize, "/cores");
4516
4517  // Truncate if theoretical string was longer than bufferSize
4518  n = MIN2(n, (int)bufferSize);
4519
4520  return n;
4521}
4522