1 /*
2 * Copyright (c) 1999, 2015, 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 #include "utilities/globalDefinitions.hpp"
26 #include "prims/jvm.h"
27 #include "semaphore_posix.hpp"
28 #include "runtime/frame.inline.hpp"
29 #include "runtime/interfaceSupport.hpp"
30 #include "runtime/os.hpp"
31 #include "utilities/vmError.hpp"
32
33 #include <signal.h>
34 #include <unistd.h>
35 #include <sys/resource.h>
36 #include <sys/utsname.h>
37 #include <pthread.h>
38 #include <semaphore.h>
39 #include <signal.h>
40
41 // Todo: provide a os::get_max_process_id() or similar. Number of processes
42 // may have been configured, can be read more accurately from proc fs etc.
43 #ifndef MAX_PID
44 #define MAX_PID INT_MAX
45 #endif
46 #define IS_VALID_PID(p) (p > 0 && p < MAX_PID)
47
48 // Check core dump limit and report possible place where core can be found
49 void os::check_dump_limit(char* buffer, size_t bufferSize) {
50 int n;
51 struct rlimit rlim;
52 bool success;
53
54 char core_path[PATH_MAX];
55 n = get_core_path(core_path, PATH_MAX);
56
57 if (n <= 0) {
58 jio_snprintf(buffer, bufferSize, "core.%d (may not exist)", current_process_id());
59 success = true;
60 #ifdef LINUX
61 } else if (core_path[0] == '"') { // redirect to user process
62 jio_snprintf(buffer, bufferSize, "Core dumps may be processed with %s", core_path);
63 success = true;
64 #endif
65 } else if (getrlimit(RLIMIT_CORE, &rlim) != 0) {
66 jio_snprintf(buffer, bufferSize, "%s (may not exist)", core_path);
67 success = true;
68 } else {
69 switch(rlim.rlim_cur) {
70 case RLIM_INFINITY:
71 jio_snprintf(buffer, bufferSize, "%s", core_path);
72 success = true;
73 break;
74 case 0:
75 jio_snprintf(buffer, bufferSize, "Core dumps have been disabled. To enable core dumping, try \"ulimit -c unlimited\" before starting Java again");
76 success = false;
77 break;
78 default:
79 jio_snprintf(buffer, bufferSize, "%s (max size %lu kB). To ensure a full core dump, try \"ulimit -c unlimited\" before starting Java again", core_path, (unsigned long)(rlim.rlim_cur >> 10));
80 success = true;
81 break;
82 }
83 }
84
85 VMError::record_coredump_status(buffer, success);
86 }
87
88 int os::get_native_stack(address* stack, int frames, int toSkip) {
89 #ifdef _NMT_NOINLINE_
90 toSkip++;
91 #endif
92
93 int frame_idx = 0;
94 int num_of_frames; // number of frames captured
95 frame fr = os::current_frame();
96 while (fr.pc() && frame_idx < frames) {
97 if (toSkip > 0) {
98 toSkip --;
99 } else {
100 stack[frame_idx ++] = fr.pc();
101 }
102 if (fr.fp() == NULL || fr.cb() != NULL ||
103 fr.sender_pc() == NULL || os::is_first_C_frame(&fr)) break;
104
105 if (fr.sender_pc() && !os::is_first_C_frame(&fr)) {
106 fr = os::get_sender_for_C_frame(&fr);
107 } else {
108 break;
109 }
110 }
111 num_of_frames = frame_idx;
112 for (; frame_idx < frames; frame_idx ++) {
113 stack[frame_idx] = NULL;
114 }
115
116 return num_of_frames;
117 }
118
119
120 bool os::unsetenv(const char* name) {
121 assert(name != NULL, "Null pointer");
122 return (::unsetenv(name) == 0);
123 }
124
125 int os::get_last_error() {
126 return errno;
127 }
128
129 bool os::is_debugger_attached() {
130 // not implemented
131 return false;
132 }
133
134 void os::wait_for_keypress_at_exit(void) {
135 // don't do anything on posix platforms
136 return;
137 }
138
139 // Multiple threads can race in this code, and can remap over each other with MAP_FIXED,
140 // so on posix, unmap the section at the start and at the end of the chunk that we mapped
141 // rather than unmapping and remapping the whole chunk to get requested alignment.
142 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
143 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
144 "Alignment must be a multiple of allocation granularity (page size)");
145 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
146
147 size_t extra_size = size + alignment;
148 assert(extra_size >= size, "overflow, size is too large to allow alignment");
149
150 char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
151
152 if (extra_base == NULL) {
153 return NULL;
154 }
155
156 // Do manual alignment
157 char* aligned_base = (char*) align_size_up((uintptr_t) extra_base, alignment);
158
159 // [ | | ]
160 // ^ extra_base
161 // ^ extra_base + begin_offset == aligned_base
162 // extra_base + begin_offset + size ^
163 // extra_base + extra_size ^
164 // |<>| == begin_offset
165 // end_offset == |<>|
166 size_t begin_offset = aligned_base - extra_base;
167 size_t end_offset = (extra_base + extra_size) - (aligned_base + size);
168
169 if (begin_offset > 0) {
170 os::release_memory(extra_base, begin_offset);
171 }
172
173 if (end_offset > 0) {
174 os::release_memory(extra_base + begin_offset + size, end_offset);
175 }
176
177 return aligned_base;
178 }
179
180 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
181 return vsnprintf(buf, len, fmt, args);
182 }
183
184 void os::Posix::print_load_average(outputStream* st) {
185 st->print("load average:");
186 double loadavg[3];
187 os::loadavg(loadavg, 3);
188 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
189 st->cr();
190 }
191
192 void os::Posix::print_rlimit_info(outputStream* st) {
193 st->print("rlimit:");
194 struct rlimit rlim;
195
196 st->print(" STACK ");
197 getrlimit(RLIMIT_STACK, &rlim);
198 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
199 else st->print("%luk", rlim.rlim_cur >> 10);
200
201 st->print(", CORE ");
202 getrlimit(RLIMIT_CORE, &rlim);
203 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
204 else st->print("%luk", rlim.rlim_cur >> 10);
205
206 // Isn't there on solaris
207 #if !defined(TARGET_OS_FAMILY_solaris) && !defined(TARGET_OS_FAMILY_aix)
208 st->print(", NPROC ");
209 getrlimit(RLIMIT_NPROC, &rlim);
210 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
211 else st->print("%lu", rlim.rlim_cur);
212 #endif
213
214 st->print(", NOFILE ");
215 getrlimit(RLIMIT_NOFILE, &rlim);
216 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
217 else st->print("%lu", rlim.rlim_cur);
218
219 st->print(", AS ");
220 getrlimit(RLIMIT_AS, &rlim);
221 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
222 else st->print("%luk", rlim.rlim_cur >> 10);
223 st->cr();
224 }
225
226 void os::Posix::print_uname_info(outputStream* st) {
227 // kernel
228 st->print("uname:");
229 struct utsname name;
230 uname(&name);
231 st->print("%s ", name.sysname);
232 #ifdef ASSERT
233 st->print("%s ", name.nodename);
234 #endif
235 st->print("%s ", name.release);
236 st->print("%s ", name.version);
237 st->print("%s", name.machine);
238 st->cr();
239 }
240
241 #ifndef PRODUCT
242 bool os::get_host_name(char* buf, size_t buflen) {
243 struct utsname name;
244 uname(&name);
245 jio_snprintf(buf, buflen, "%s", name.nodename);
246 return true;
247 }
248 #endif // PRODUCT
249
250 bool os::has_allocatable_memory_limit(julong* limit) {
251 struct rlimit rlim;
252 int getrlimit_res = getrlimit(RLIMIT_AS, &rlim);
253 // if there was an error when calling getrlimit, assume that there is no limitation
254 // on virtual memory.
255 bool result;
256 if ((getrlimit_res != 0) || (rlim.rlim_cur == RLIM_INFINITY)) {
257 result = false;
258 } else {
259 *limit = (julong)rlim.rlim_cur;
260 result = true;
261 }
262 #ifdef _LP64
263 return result;
264 #else
265 // arbitrary virtual space limit for 32 bit Unices found by testing. If
266 // getrlimit above returned a limit, bound it with this limit. Otherwise
267 // directly use it.
268 const julong max_virtual_limit = (julong)3800*M;
269 if (result) {
270 *limit = MIN2(*limit, max_virtual_limit);
271 } else {
272 *limit = max_virtual_limit;
273 }
274
275 // bound by actually allocatable memory. The algorithm uses two bounds, an
276 // upper and a lower limit. The upper limit is the current highest amount of
277 // memory that could not be allocated, the lower limit is the current highest
278 // amount of memory that could be allocated.
279 // The algorithm iteratively refines the result by halving the difference
280 // between these limits, updating either the upper limit (if that value could
281 // not be allocated) or the lower limit (if the that value could be allocated)
282 // until the difference between these limits is "small".
283
284 // the minimum amount of memory we care about allocating.
285 const julong min_allocation_size = M;
286
287 julong upper_limit = *limit;
288
289 // first check a few trivial cases
290 if (is_allocatable(upper_limit) || (upper_limit <= min_allocation_size)) {
291 *limit = upper_limit;
292 } else if (!is_allocatable(min_allocation_size)) {
293 // we found that not even min_allocation_size is allocatable. Return it
294 // anyway. There is no point to search for a better value any more.
295 *limit = min_allocation_size;
296 } else {
297 // perform the binary search.
298 julong lower_limit = min_allocation_size;
299 while ((upper_limit - lower_limit) > min_allocation_size) {
300 julong temp_limit = ((upper_limit - lower_limit) / 2) + lower_limit;
301 temp_limit = align_size_down_(temp_limit, min_allocation_size);
302 if (is_allocatable(temp_limit)) {
303 lower_limit = temp_limit;
304 } else {
305 upper_limit = temp_limit;
306 }
307 }
308 *limit = lower_limit;
309 }
310 return true;
311 #endif
312 }
313
314 const char* os::get_current_directory(char *buf, size_t buflen) {
315 return getcwd(buf, buflen);
316 }
317
318 FILE* os::open(int fd, const char* mode) {
319 return ::fdopen(fd, mode);
320 }
321
322 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
323 // which is used to find statically linked in agents.
324 // Parameters:
325 // sym_name: Symbol in library we are looking for
326 // lib_name: Name of library to look in, NULL for shared libs.
327 // is_absolute_path == true if lib_name is absolute path to agent
328 // such as "/a/b/libL.so"
329 // == false if only the base name of the library is passed in
330 // such as "L"
331 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
332 bool is_absolute_path) {
333 char *agent_entry_name;
334 size_t len;
335 size_t name_len;
336 size_t prefix_len = strlen(JNI_LIB_PREFIX);
337 size_t suffix_len = strlen(JNI_LIB_SUFFIX);
338 const char *start;
339
340 if (lib_name != NULL) {
341 len = name_len = strlen(lib_name);
342 if (is_absolute_path) {
343 // Need to strip path, prefix and suffix
344 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
345 lib_name = ++start;
346 }
347 if (len <= (prefix_len + suffix_len)) {
348 return NULL;
349 }
350 lib_name += prefix_len;
351 name_len = strlen(lib_name) - suffix_len;
352 }
353 }
354 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
355 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
356 if (agent_entry_name == NULL) {
357 return NULL;
358 }
359 strcpy(agent_entry_name, sym_name);
360 if (lib_name != NULL) {
361 strcat(agent_entry_name, "_");
362 strncat(agent_entry_name, lib_name, name_len);
363 }
364 return agent_entry_name;
365 }
366
367 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
368 assert(thread == Thread::current(), "thread consistency check");
369
370 ParkEvent * const slp = thread->_SleepEvent ;
371 slp->reset() ;
372 OrderAccess::fence() ;
373
374 if (interruptible) {
375 jlong prevtime = javaTimeNanos();
376
377 for (;;) {
378 if (os::is_interrupted(thread, true)) {
379 return OS_INTRPT;
380 }
381
382 jlong newtime = javaTimeNanos();
383
384 if (newtime - prevtime < 0) {
385 // time moving backwards, should only happen if no monotonic clock
386 // not a guarantee() because JVM should not abort on kernel/glibc bugs
387 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected in os::sleep(interruptible)");
388 } else {
389 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
390 }
391
392 if (millis <= 0) {
393 return OS_OK;
394 }
395
396 prevtime = newtime;
397
398 {
399 assert(thread->is_Java_thread(), "sanity check");
400 JavaThread *jt = (JavaThread *) thread;
401 ThreadBlockInVM tbivm(jt);
402 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
403
404 jt->set_suspend_equivalent();
405 // cleared by handle_special_suspend_equivalent_condition() or
406 // java_suspend_self() via check_and_wait_while_suspended()
407
408 slp->park(millis);
409
410 // were we externally suspended while we were waiting?
411 jt->check_and_wait_while_suspended();
412 }
413 }
414 } else {
415 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
416 jlong prevtime = javaTimeNanos();
417
418 for (;;) {
419 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
420 // the 1st iteration ...
421 jlong newtime = javaTimeNanos();
422
423 if (newtime - prevtime < 0) {
424 // time moving backwards, should only happen if no monotonic clock
425 // not a guarantee() because JVM should not abort on kernel/glibc bugs
426 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected on os::sleep(!interruptible)");
427 } else {
428 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
429 }
430
431 if (millis <= 0) break ;
432
433 prevtime = newtime;
434 slp->park(millis);
435 }
436 return OS_OK ;
437 }
438 }
439
440 ////////////////////////////////////////////////////////////////////////////////
441 // interrupt support
442
443 void os::interrupt(Thread* thread) {
444 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
445 "possibility of dangling Thread pointer");
446
447 OSThread* osthread = thread->osthread();
448
449 if (!osthread->interrupted()) {
450 osthread->set_interrupted(true);
451 // More than one thread can get here with the same value of osthread,
452 // resulting in multiple notifications. We do, however, want the store
453 // to interrupted() to be visible to other threads before we execute unpark().
454 OrderAccess::fence();
455 ParkEvent * const slp = thread->_SleepEvent ;
456 if (slp != NULL) slp->unpark() ;
457 }
458
459 // For JSR166. Unpark even if interrupt status already was set
460 if (thread->is_Java_thread())
461 ((JavaThread*)thread)->parker()->unpark();
462
463 ParkEvent * ev = thread->_ParkEvent ;
464 if (ev != NULL) ev->unpark() ;
465
466 }
467
468 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
469 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
470 "possibility of dangling Thread pointer");
471
472 OSThread* osthread = thread->osthread();
473
474 bool interrupted = osthread->interrupted();
475
476 // NOTE that since there is no "lock" around the interrupt and
477 // is_interrupted operations, there is the possibility that the
478 // interrupted flag (in osThread) will be "false" but that the
479 // low-level events will be in the signaled state. This is
480 // intentional. The effect of this is that Object.wait() and
481 // LockSupport.park() will appear to have a spurious wakeup, which
482 // is allowed and not harmful, and the possibility is so rare that
483 // it is not worth the added complexity to add yet another lock.
484 // For the sleep event an explicit reset is performed on entry
485 // to os::sleep, so there is no early return. It has also been
486 // recommended not to put the interrupted flag into the "event"
487 // structure because it hides the issue.
488 if (interrupted && clear_interrupted) {
489 osthread->set_interrupted(false);
490 // consider thread->_SleepEvent->reset() ... optional optimization
491 }
492
493 return interrupted;
494 }
495
496 // Returned string is a constant. For unknown signals "UNKNOWN" is returned.
497 const char* os::Posix::get_signal_name(int sig, char* out, size_t outlen) {
498
499 static const struct {
500 int sig; const char* name;
501 }
502 info[] =
503 {
504 { SIGABRT, "SIGABRT" },
505 #ifdef SIGAIO
506 { SIGAIO, "SIGAIO" },
507 #endif
508 { SIGALRM, "SIGALRM" },
509 #ifdef SIGALRM1
510 { SIGALRM1, "SIGALRM1" },
511 #endif
512 { SIGBUS, "SIGBUS" },
513 #ifdef SIGCANCEL
514 { SIGCANCEL, "SIGCANCEL" },
515 #endif
516 { SIGCHLD, "SIGCHLD" },
517 #ifdef SIGCLD
518 { SIGCLD, "SIGCLD" },
519 #endif
520 { SIGCONT, "SIGCONT" },
521 #ifdef SIGCPUFAIL
522 { SIGCPUFAIL, "SIGCPUFAIL" },
523 #endif
524 #ifdef SIGDANGER
525 { SIGDANGER, "SIGDANGER" },
526 #endif
527 #ifdef SIGDIL
528 { SIGDIL, "SIGDIL" },
529 #endif
530 #ifdef SIGEMT
531 { SIGEMT, "SIGEMT" },
532 #endif
533 { SIGFPE, "SIGFPE" },
534 #ifdef SIGFREEZE
535 { SIGFREEZE, "SIGFREEZE" },
536 #endif
537 #ifdef SIGGFAULT
538 { SIGGFAULT, "SIGGFAULT" },
539 #endif
540 #ifdef SIGGRANT
541 { SIGGRANT, "SIGGRANT" },
542 #endif
543 { SIGHUP, "SIGHUP" },
544 { SIGILL, "SIGILL" },
545 { SIGINT, "SIGINT" },
546 #ifdef SIGIO
547 { SIGIO, "SIGIO" },
548 #endif
549 #ifdef SIGIOINT
550 { SIGIOINT, "SIGIOINT" },
551 #endif
552 #ifdef SIGIOT
553 // SIGIOT is there for BSD compatibility, but on most Unices just a
554 // synonym for SIGABRT. The result should be "SIGABRT", not
555 // "SIGIOT".
556 #if (SIGIOT != SIGABRT )
557 { SIGIOT, "SIGIOT" },
558 #endif
559 #endif
560 #ifdef SIGKAP
561 { SIGKAP, "SIGKAP" },
562 #endif
563 { SIGKILL, "SIGKILL" },
564 #ifdef SIGLOST
565 { SIGLOST, "SIGLOST" },
566 #endif
567 #ifdef SIGLWP
568 { SIGLWP, "SIGLWP" },
569 #endif
570 #ifdef SIGLWPTIMER
571 { SIGLWPTIMER, "SIGLWPTIMER" },
572 #endif
573 #ifdef SIGMIGRATE
574 { SIGMIGRATE, "SIGMIGRATE" },
575 #endif
576 #ifdef SIGMSG
577 { SIGMSG, "SIGMSG" },
578 #endif
579 { SIGPIPE, "SIGPIPE" },
580 #ifdef SIGPOLL
581 { SIGPOLL, "SIGPOLL" },
582 #endif
583 #ifdef SIGPRE
584 { SIGPRE, "SIGPRE" },
585 #endif
586 { SIGPROF, "SIGPROF" },
587 #ifdef SIGPTY
588 { SIGPTY, "SIGPTY" },
589 #endif
590 #ifdef SIGPWR
591 { SIGPWR, "SIGPWR" },
592 #endif
593 { SIGQUIT, "SIGQUIT" },
594 #ifdef SIGRECONFIG
595 { SIGRECONFIG, "SIGRECONFIG" },
596 #endif
597 #ifdef SIGRECOVERY
598 { SIGRECOVERY, "SIGRECOVERY" },
599 #endif
600 #ifdef SIGRESERVE
601 { SIGRESERVE, "SIGRESERVE" },
602 #endif
603 #ifdef SIGRETRACT
604 { SIGRETRACT, "SIGRETRACT" },
605 #endif
606 #ifdef SIGSAK
607 { SIGSAK, "SIGSAK" },
608 #endif
609 { SIGSEGV, "SIGSEGV" },
610 #ifdef SIGSOUND
611 { SIGSOUND, "SIGSOUND" },
612 #endif
613 { SIGSTOP, "SIGSTOP" },
614 { SIGSYS, "SIGSYS" },
615 #ifdef SIGSYSERROR
616 { SIGSYSERROR, "SIGSYSERROR" },
617 #endif
618 #ifdef SIGTALRM
619 { SIGTALRM, "SIGTALRM" },
620 #endif
621 { SIGTERM, "SIGTERM" },
622 #ifdef SIGTHAW
623 { SIGTHAW, "SIGTHAW" },
624 #endif
625 { SIGTRAP, "SIGTRAP" },
626 #ifdef SIGTSTP
627 { SIGTSTP, "SIGTSTP" },
628 #endif
629 { SIGTTIN, "SIGTTIN" },
630 { SIGTTOU, "SIGTTOU" },
631 #ifdef SIGURG
632 { SIGURG, "SIGURG" },
633 #endif
634 { SIGUSR1, "SIGUSR1" },
635 { SIGUSR2, "SIGUSR2" },
636 #ifdef SIGVIRT
637 { SIGVIRT, "SIGVIRT" },
638 #endif
639 { SIGVTALRM, "SIGVTALRM" },
640 #ifdef SIGWAITING
641 { SIGWAITING, "SIGWAITING" },
642 #endif
643 #ifdef SIGWINCH
644 { SIGWINCH, "SIGWINCH" },
645 #endif
646 #ifdef SIGWINDOW
647 { SIGWINDOW, "SIGWINDOW" },
648 #endif
649 { SIGXCPU, "SIGXCPU" },
650 { SIGXFSZ, "SIGXFSZ" },
651 #ifdef SIGXRES
652 { SIGXRES, "SIGXRES" },
653 #endif
654 { -1, NULL }
655 };
656
657 const char* ret = NULL;
658
659 #ifdef SIGRTMIN
660 if (sig >= SIGRTMIN && sig <= SIGRTMAX) {
661 if (sig == SIGRTMIN) {
662 ret = "SIGRTMIN";
663 } else if (sig == SIGRTMAX) {
664 ret = "SIGRTMAX";
665 } else {
666 jio_snprintf(out, outlen, "SIGRTMIN+%d", sig - SIGRTMIN);
667 return out;
668 }
669 }
670 #endif
671
672 if (sig > 0) {
673 for (int idx = 0; info[idx].sig != -1; idx ++) {
674 if (info[idx].sig == sig) {
675 ret = info[idx].name;
676 break;
677 }
678 }
679 }
680
681 if (!ret) {
682 if (!is_valid_signal(sig)) {
683 ret = "INVALID";
684 } else {
685 ret = "UNKNOWN";
686 }
687 }
688
689 if (out && outlen > 0) {
690 strncpy(out, ret, outlen);
691 out[outlen - 1] = '\0';
692 }
693 return out;
694 }
695
696 // Returns true if signal number is valid.
697 bool os::Posix::is_valid_signal(int sig) {
698 // MacOS not really POSIX compliant: sigaddset does not return
699 // an error for invalid signal numbers. However, MacOS does not
700 // support real time signals and simply seems to have just 33
701 // signals with no holes in the signal range.
702 #ifdef __APPLE__
703 return sig >= 1 && sig < NSIG;
704 #else
705 // Use sigaddset to check for signal validity.
706 sigset_t set;
707 if (sigaddset(&set, sig) == -1 && errno == EINVAL) {
708 return false;
709 }
710 return true;
711 #endif
712 }
713
714 #define NUM_IMPORTANT_SIGS 32
715 // Returns one-line short description of a signal set in a user provided buffer.
716 const char* os::Posix::describe_signal_set_short(const sigset_t* set, char* buffer, size_t buf_size) {
717 assert(buf_size == (NUM_IMPORTANT_SIGS + 1), "wrong buffer size");
718 // Note: for shortness, just print out the first 32. That should
719 // cover most of the useful ones, apart from realtime signals.
720 for (int sig = 1; sig <= NUM_IMPORTANT_SIGS; sig++) {
721 const int rc = sigismember(set, sig);
722 if (rc == -1 && errno == EINVAL) {
723 buffer[sig-1] = '?';
724 } else {
725 buffer[sig-1] = rc == 0 ? '0' : '1';
726 }
727 }
728 buffer[NUM_IMPORTANT_SIGS] = 0;
729 return buffer;
730 }
731
732 // Prints one-line description of a signal set.
733 void os::Posix::print_signal_set_short(outputStream* st, const sigset_t* set) {
734 char buf[NUM_IMPORTANT_SIGS + 1];
735 os::Posix::describe_signal_set_short(set, buf, sizeof(buf));
736 st->print("%s", buf);
737 }
738
739 // Writes one-line description of a combination of sigaction.sa_flags into a user
740 // provided buffer. Returns that buffer.
741 const char* os::Posix::describe_sa_flags(int flags, char* buffer, size_t size) {
742 char* p = buffer;
743 size_t remaining = size;
744 bool first = true;
745 int idx = 0;
746
747 assert(buffer, "invalid argument");
748
749 if (size == 0) {
750 return buffer;
751 }
752
753 strncpy(buffer, "none", size);
754
755 const struct {
756 int i;
757 const char* s;
758 } flaginfo [] = {
759 { SA_NOCLDSTOP, "SA_NOCLDSTOP" },
760 { SA_ONSTACK, "SA_ONSTACK" },
761 { SA_RESETHAND, "SA_RESETHAND" },
762 { SA_RESTART, "SA_RESTART" },
763 { SA_SIGINFO, "SA_SIGINFO" },
764 { SA_NOCLDWAIT, "SA_NOCLDWAIT" },
765 { SA_NODEFER, "SA_NODEFER" },
766 #ifdef AIX
767 { SA_ONSTACK, "SA_ONSTACK" },
768 { SA_OLDSTYLE, "SA_OLDSTYLE" },
769 #endif
770 { 0, NULL }
771 };
772
773 for (idx = 0; flaginfo[idx].s && remaining > 1; idx++) {
774 if (flags & flaginfo[idx].i) {
775 if (first) {
776 jio_snprintf(p, remaining, "%s", flaginfo[idx].s);
777 first = false;
778 } else {
779 jio_snprintf(p, remaining, "|%s", flaginfo[idx].s);
780 }
781 const size_t len = strlen(p);
782 p += len;
783 remaining -= len;
784 }
785 }
786
787 buffer[size - 1] = '\0';
788
789 return buffer;
790 }
791
792 // Prints one-line description of a combination of sigaction.sa_flags.
793 void os::Posix::print_sa_flags(outputStream* st, int flags) {
794 char buffer[0x100];
795 os::Posix::describe_sa_flags(flags, buffer, sizeof(buffer));
796 st->print("%s", buffer);
797 }
798
799 // Helper function for os::Posix::print_siginfo_...():
800 // return a textual description for signal code.
801 struct enum_sigcode_desc_t {
802 const char* s_name;
803 const char* s_desc;
804 };
805
806 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) {
807
808 const struct {
809 int sig; int code; const char* s_code; const char* s_desc;
810 } t1 [] = {
811 { SIGILL, ILL_ILLOPC, "ILL_ILLOPC", "Illegal opcode." },
812 { SIGILL, ILL_ILLOPN, "ILL_ILLOPN", "Illegal operand." },
813 { SIGILL, ILL_ILLADR, "ILL_ILLADR", "Illegal addressing mode." },
814 { SIGILL, ILL_ILLTRP, "ILL_ILLTRP", "Illegal trap." },
815 { SIGILL, ILL_PRVOPC, "ILL_PRVOPC", "Privileged opcode." },
816 { SIGILL, ILL_PRVREG, "ILL_PRVREG", "Privileged register." },
817 { SIGILL, ILL_COPROC, "ILL_COPROC", "Coprocessor error." },
818 { SIGILL, ILL_BADSTK, "ILL_BADSTK", "Internal stack error." },
819 #if defined(IA64) && defined(LINUX)
820 { SIGILL, ILL_BADIADDR, "ILL_BADIADDR", "Unimplemented instruction address" },
821 { SIGILL, ILL_BREAK, "ILL_BREAK", "Application Break instruction" },
822 #endif
823 { SIGFPE, FPE_INTDIV, "FPE_INTDIV", "Integer divide by zero." },
824 { SIGFPE, FPE_INTOVF, "FPE_INTOVF", "Integer overflow." },
825 { SIGFPE, FPE_FLTDIV, "FPE_FLTDIV", "Floating-point divide by zero." },
826 { SIGFPE, FPE_FLTOVF, "FPE_FLTOVF", "Floating-point overflow." },
827 { SIGFPE, FPE_FLTUND, "FPE_FLTUND", "Floating-point underflow." },
828 { SIGFPE, FPE_FLTRES, "FPE_FLTRES", "Floating-point inexact result." },
829 { SIGFPE, FPE_FLTINV, "FPE_FLTINV", "Invalid floating-point operation." },
830 { SIGFPE, FPE_FLTSUB, "FPE_FLTSUB", "Subscript out of range." },
831 { SIGSEGV, SEGV_MAPERR, "SEGV_MAPERR", "Address not mapped to object." },
832 { SIGSEGV, SEGV_ACCERR, "SEGV_ACCERR", "Invalid permissions for mapped object." },
833 #ifdef AIX
834 // no explanation found what keyerr would be
835 { SIGSEGV, SEGV_KEYERR, "SEGV_KEYERR", "key error" },
836 #endif
837 #if defined(IA64) && !defined(AIX)
838 { SIGSEGV, SEGV_PSTKOVF, "SEGV_PSTKOVF", "Paragraph stack overflow" },
839 #endif
840 #if defined(__sparc) && defined(SOLARIS)
841 // define Solaris Sparc M7 ADI SEGV signals
842 #if !defined(SEGV_ACCADI)
843 #define SEGV_ACCADI 3
844 #endif
845 { SIGSEGV, SEGV_ACCADI, "SEGV_ACCADI", "ADI not enabled for mapped object." },
846 #if !defined(SEGV_ACCDERR)
847 #define SEGV_ACCDERR 4
848 #endif
849 { SIGSEGV, SEGV_ACCDERR, "SEGV_ACCDERR", "ADI disrupting exception." },
850 #if !defined(SEGV_ACCPERR)
851 #define SEGV_ACCPERR 5
852 #endif
853 { SIGSEGV, SEGV_ACCPERR, "SEGV_ACCPERR", "ADI precise exception." },
854 #endif // defined(__sparc) && defined(SOLARIS)
855 { SIGBUS, BUS_ADRALN, "BUS_ADRALN", "Invalid address alignment." },
856 { SIGBUS, BUS_ADRERR, "BUS_ADRERR", "Nonexistent physical address." },
857 { SIGBUS, BUS_OBJERR, "BUS_OBJERR", "Object-specific hardware error." },
858 { SIGTRAP, TRAP_BRKPT, "TRAP_BRKPT", "Process breakpoint." },
859 { SIGTRAP, TRAP_TRACE, "TRAP_TRACE", "Process trace trap." },
860 { SIGCHLD, CLD_EXITED, "CLD_EXITED", "Child has exited." },
861 { SIGCHLD, CLD_KILLED, "CLD_KILLED", "Child has terminated abnormally and did not create a core file." },
862 { SIGCHLD, CLD_DUMPED, "CLD_DUMPED", "Child has terminated abnormally and created a core file." },
863 { SIGCHLD, CLD_TRAPPED, "CLD_TRAPPED", "Traced child has trapped." },
864 { SIGCHLD, CLD_STOPPED, "CLD_STOPPED", "Child has stopped." },
865 { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." },
866 #ifdef SIGPOLL
867 { SIGPOLL, POLL_OUT, "POLL_OUT", "Output buffers available." },
868 { SIGPOLL, POLL_MSG, "POLL_MSG", "Input message available." },
869 { SIGPOLL, POLL_ERR, "POLL_ERR", "I/O error." },
870 { SIGPOLL, POLL_PRI, "POLL_PRI", "High priority input available." },
871 { SIGPOLL, POLL_HUP, "POLL_HUP", "Device disconnected. [Option End]" },
872 #endif
873 { -1, -1, NULL, NULL }
874 };
875
876 // Codes valid in any signal context.
877 const struct {
878 int code; const char* s_code; const char* s_desc;
879 } t2 [] = {
880 { SI_USER, "SI_USER", "Signal sent by kill()." },
881 { SI_QUEUE, "SI_QUEUE", "Signal sent by the sigqueue()." },
882 { SI_TIMER, "SI_TIMER", "Signal generated by expiration of a timer set by timer_settime()." },
883 { SI_ASYNCIO, "SI_ASYNCIO", "Signal generated by completion of an asynchronous I/O request." },
884 { SI_MESGQ, "SI_MESGQ", "Signal generated by arrival of a message on an empty message queue." },
885 // Linux specific
886 #ifdef SI_TKILL
887 { SI_TKILL, "SI_TKILL", "Signal sent by tkill (pthread_kill)" },
888 #endif
889 #ifdef SI_DETHREAD
890 { SI_DETHREAD, "SI_DETHREAD", "Signal sent by execve() killing subsidiary threads" },
891 #endif
892 #ifdef SI_KERNEL
893 { SI_KERNEL, "SI_KERNEL", "Signal sent by kernel." },
894 #endif
895 #ifdef SI_SIGIO
896 { SI_SIGIO, "SI_SIGIO", "Signal sent by queued SIGIO" },
897 #endif
898
899 #ifdef AIX
900 { SI_UNDEFINED, "SI_UNDEFINED","siginfo contains partial information" },
901 { SI_EMPTY, "SI_EMPTY", "siginfo contains no useful information" },
902 #endif
903
904 #ifdef __sun
905 { SI_NOINFO, "SI_NOINFO", "No signal information" },
906 { SI_RCTL, "SI_RCTL", "kernel generated signal via rctl action" },
907 { SI_LWP, "SI_LWP", "Signal sent via lwp_kill" },
908 #endif
909
910 { -1, NULL, NULL }
911 };
912
913 const char* s_code = NULL;
914 const char* s_desc = NULL;
915
916 for (int i = 0; t1[i].sig != -1; i ++) {
917 if (t1[i].sig == si->si_signo && t1[i].code == si->si_code) {
918 s_code = t1[i].s_code;
919 s_desc = t1[i].s_desc;
920 break;
921 }
922 }
923
924 if (s_code == NULL) {
925 for (int i = 0; t2[i].s_code != NULL; i ++) {
926 if (t2[i].code == si->si_code) {
927 s_code = t2[i].s_code;
928 s_desc = t2[i].s_desc;
929 }
930 }
931 }
932
933 if (s_code == NULL) {
934 out->s_name = "unknown";
935 out->s_desc = "unknown";
936 return false;
937 }
938
939 out->s_name = s_code;
940 out->s_desc = s_desc;
941
942 return true;
943 }
944
945 // A POSIX conform, platform-independend siginfo print routine.
946 // Short print out on one line.
947 void os::Posix::print_siginfo_brief(outputStream* os, const siginfo_t* si) {
948 char buf[20];
949 os->print("siginfo: ");
950
951 if (!si) {
952 os->print("<null>");
953 return;
954 }
955
956 // See print_siginfo_full() for details.
957 const int sig = si->si_signo;
958
959 os->print("si_signo: %d (%s)", sig, os::Posix::get_signal_name(sig, buf, sizeof(buf)));
960
961 enum_sigcode_desc_t ed;
962 if (get_signal_code_description(si, &ed)) {
963 os->print(", si_code: %d (%s)", si->si_code, ed.s_name);
964 } else {
965 os->print(", si_code: %d (unknown)", si->si_code);
966 }
967
968 if (si->si_errno) {
969 os->print(", si_errno: %d", si->si_errno);
970 }
971
972 const int me = (int) ::getpid();
973 const int pid = (int) si->si_pid;
974
975 if (si->si_code == SI_USER || si->si_code == SI_QUEUE) {
976 if (IS_VALID_PID(pid) && pid != me) {
977 os->print(", sent from pid: %d (uid: %d)", pid, (int) si->si_uid);
978 }
979 } else if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
980 sig == SIGTRAP || sig == SIGFPE) {
981 os->print(", si_addr: " PTR_FORMAT, p2i(si->si_addr));
982 #ifdef SIGPOLL
983 } else if (sig == SIGPOLL) {
984 os->print(", si_band: " PTR64_FORMAT, (uint64_t)si->si_band);
985 #endif
986 } else if (sig == SIGCHLD) {
987 os->print_cr(", si_pid: %d, si_uid: %d, si_status: %d", (int) si->si_pid, si->si_uid, si->si_status);
988 }
989 }
990
991 int os::Posix::unblock_thread_signal_mask(const sigset_t *set) {
992 return pthread_sigmask(SIG_UNBLOCK, set, NULL);
993 }
994
995 address os::Posix::ucontext_get_pc(ucontext_t* ctx) {
996 #ifdef TARGET_OS_FAMILY_linux
997 return Linux::ucontext_get_pc(ctx);
998 #elif defined(TARGET_OS_FAMILY_solaris)
999 return Solaris::ucontext_get_pc(ctx);
1000 #elif defined(TARGET_OS_FAMILY_aix)
1001 return Aix::ucontext_get_pc(ctx);
1002 #elif defined(TARGET_OS_FAMILY_bsd)
1003 return Bsd::ucontext_get_pc(ctx);
1004 #else
1005 VMError::report_and_die("unimplemented ucontext_get_pc");
1006 #endif
1007 }
1008
1009 void os::Posix::ucontext_set_pc(ucontext_t* ctx, address pc) {
1010 #ifdef TARGET_OS_FAMILY_linux
1011 Linux::ucontext_set_pc(ctx, pc);
1012 #elif defined(TARGET_OS_FAMILY_solaris)
1013 Solaris::ucontext_set_pc(ctx, pc);
1014 #elif defined(TARGET_OS_FAMILY_aix)
1015 Aix::ucontext_set_pc(ctx, pc);
1016 #elif defined(TARGET_OS_FAMILY_bsd)
1017 Bsd::ucontext_set_pc(ctx, pc);
1018 #else
1019 VMError::report_and_die("unimplemented ucontext_get_pc");
1020 #endif
1021 }
1022
1023
1024 os::WatcherThreadCrashProtection::WatcherThreadCrashProtection() {
1025 assert(Thread::current()->is_Watcher_thread(), "Must be WatcherThread");
1026 }
1027
1028 /*
1029 * See the caveats for this class in os_posix.hpp
1030 * Protects the callback call so that SIGSEGV / SIGBUS jumps back into this
1031 * method and returns false. If none of the signals are raised, returns true.
1032 * The callback is supposed to provide the method that should be protected.
1033 */
1034 bool os::WatcherThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
1035 sigset_t saved_sig_mask;
1036
1037 assert(Thread::current()->is_Watcher_thread(), "Only for WatcherThread");
1038 assert(!WatcherThread::watcher_thread()->has_crash_protection(),
1039 "crash_protection already set?");
1040
1041 // we cannot rely on sigsetjmp/siglongjmp to save/restore the signal mask
1042 // since on at least some systems (OS X) siglongjmp will restore the mask
1043 // for the process, not the thread
1044 pthread_sigmask(0, NULL, &saved_sig_mask);
1045 if (sigsetjmp(_jmpbuf, 0) == 0) {
1046 // make sure we can see in the signal handler that we have crash protection
1047 // installed
1048 WatcherThread::watcher_thread()->set_crash_protection(this);
1049 cb.call();
1050 // and clear the crash protection
1051 WatcherThread::watcher_thread()->set_crash_protection(NULL);
1052 return true;
1053 }
1054 // this happens when we siglongjmp() back
1055 pthread_sigmask(SIG_SETMASK, &saved_sig_mask, NULL);
1056 WatcherThread::watcher_thread()->set_crash_protection(NULL);
1057 return false;
1058 }
1059
1060 void os::WatcherThreadCrashProtection::restore() {
1061 assert(WatcherThread::watcher_thread()->has_crash_protection(),
1062 "must have crash protection");
1063
1064 siglongjmp(_jmpbuf, 1);
1065 }
1066
1067 void os::WatcherThreadCrashProtection::check_crash_protection(int sig,
1068 Thread* thread) {
1069
1070 if (thread != NULL &&
1071 thread->is_Watcher_thread() &&
1072 WatcherThread::watcher_thread()->has_crash_protection()) {
1073
1074 if (sig == SIGSEGV || sig == SIGBUS) {
1075 WatcherThread::watcher_thread()->crash_protection()->restore();
1076 }
1077 }
1078 }
1079
1080 #define check_with_errno(check_type, cond, msg) \
1081 do { \
1082 int err = errno; \
1083 check_type(cond, "%s; error='%s' (errno=%d)", msg, strerror(err), err); \
1084 } while (false)
1085
1086 #define assert_with_errno(cond, msg) check_with_errno(assert, cond, msg)
1087 #define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg)
1088
1089 // POSIX unamed semaphores are not supported on OS X.
1090 #ifndef __APPLE__
1091
1092 PosixSemaphore::PosixSemaphore(uint value) {
1093 int ret = sem_init(&_semaphore, 0, value);
1094
1095 guarantee_with_errno(ret == 0, "Failed to initialize semaphore");
1096 }
1097
1098 PosixSemaphore::~PosixSemaphore() {
1099 sem_destroy(&_semaphore);
1100 }
1101
1102 void PosixSemaphore::signal(uint count) {
1103 for (uint i = 0; i < count; i++) {
1104 int ret = sem_post(&_semaphore);
1105
1106 assert_with_errno(ret == 0, "sem_post failed");
1107 }
1108 }
1109
1110 void PosixSemaphore::wait() {
1111 int ret;
1112
1113 do {
1114 ret = sem_wait(&_semaphore);
1115 } while (ret != 0 && errno == EINTR);
1116
1117 assert_with_errno(ret == 0, "sem_wait failed");
1118 }
1119
1120 bool PosixSemaphore::trywait() {
1121 int ret;
1122
1123 do {
1124 ret = sem_trywait(&_semaphore);
1125 } while (ret != 0 && errno == EINTR);
1126
1127 assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed");
1128
1129 return ret == 0;
1130 }
1131
1132 bool PosixSemaphore::timedwait(struct timespec ts) {
1133 while (true) {
1134 int result = sem_timedwait(&_semaphore, &ts);
1135 if (result == 0) {
1136 return true;
1137 } else if (errno == EINTR) {
1138 continue;
1139 } else if (errno == ETIMEDOUT) {
1140 return false;
1141 } else {
1142 assert_with_errno(false, "timedwait failed");
1143 return false;
1144 }
1145 }
1146 }
1147
1148 #endif // __APPLE__