1 /* 2 * Copyright (c) 1999, 2014, 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 "runtime/frame.inline.hpp" 28 #include "runtime/interfaceSupport.hpp" 29 #include "runtime/os.hpp" 30 #include "utilities/vmError.hpp" 31 32 #include <signal.h> 33 #include <unistd.h> 34 #include <sys/resource.h> 35 #include <sys/utsname.h> 36 #include <pthread.h> 37 #include <signal.h> 38 39 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 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_create_dump_limit(void* exceptionRecord, void* contextRecord, 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::report_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 void os::Posix::print_load_average(outputStream* st) { 181 st->print("load average:"); 182 double loadavg[3]; 183 os::loadavg(loadavg, 3); 184 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]); 185 st->cr(); 186 } 187 188 void os::Posix::print_rlimit_info(outputStream* st) { 189 st->print("rlimit:"); 190 struct rlimit rlim; 191 192 st->print(" STACK "); 193 getrlimit(RLIMIT_STACK, &rlim); 194 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 195 else st->print("%uk", rlim.rlim_cur >> 10); 196 197 st->print(", CORE "); 198 getrlimit(RLIMIT_CORE, &rlim); 199 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 200 else st->print("%uk", rlim.rlim_cur >> 10); 201 202 // Isn't there on solaris 203 #if !defined(TARGET_OS_FAMILY_solaris) && !defined(TARGET_OS_FAMILY_aix) 204 st->print(", NPROC "); 205 getrlimit(RLIMIT_NPROC, &rlim); 206 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 207 else st->print("%d", rlim.rlim_cur); 208 #endif 209 210 st->print(", NOFILE "); 211 getrlimit(RLIMIT_NOFILE, &rlim); 212 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 213 else st->print("%d", rlim.rlim_cur); 214 215 st->print(", AS "); 216 getrlimit(RLIMIT_AS, &rlim); 217 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 218 else st->print("%uk", rlim.rlim_cur >> 10); 219 st->cr(); 220 } 221 222 void os::Posix::print_uname_info(outputStream* st) { 223 // kernel 224 st->print("uname:"); 225 struct utsname name; 226 uname(&name); 227 st->print("%s ", name.sysname); 228 #ifdef ASSERT 229 st->print("%s ", name.nodename); 230 #endif 231 st->print("%s ", name.release); 232 st->print("%s ", name.version); 233 st->print("%s", name.machine); 234 st->cr(); 235 } 236 237 bool os::has_allocatable_memory_limit(julong* limit) { 238 struct rlimit rlim; 239 int getrlimit_res = getrlimit(RLIMIT_AS, &rlim); 240 // if there was an error when calling getrlimit, assume that there is no limitation 241 // on virtual memory. 242 bool result; 243 if ((getrlimit_res != 0) || (rlim.rlim_cur == RLIM_INFINITY)) { 244 result = false; 245 } else { 246 *limit = (julong)rlim.rlim_cur; 247 result = true; 248 } 249 #ifdef _LP64 250 return result; 251 #else 252 // arbitrary virtual space limit for 32 bit Unices found by testing. If 253 // getrlimit above returned a limit, bound it with this limit. Otherwise 254 // directly use it. 255 const julong max_virtual_limit = (julong)3800*M; 256 if (result) { 257 *limit = MIN2(*limit, max_virtual_limit); 258 } else { 259 *limit = max_virtual_limit; 260 } 261 262 // bound by actually allocatable memory. The algorithm uses two bounds, an 263 // upper and a lower limit. The upper limit is the current highest amount of 264 // memory that could not be allocated, the lower limit is the current highest 265 // amount of memory that could be allocated. 266 // The algorithm iteratively refines the result by halving the difference 267 // between these limits, updating either the upper limit (if that value could 268 // not be allocated) or the lower limit (if the that value could be allocated) 269 // until the difference between these limits is "small". 270 271 // the minimum amount of memory we care about allocating. 272 const julong min_allocation_size = M; 273 274 julong upper_limit = *limit; 275 276 // first check a few trivial cases 277 if (is_allocatable(upper_limit) || (upper_limit <= min_allocation_size)) { 278 *limit = upper_limit; 279 } else if (!is_allocatable(min_allocation_size)) { 280 // we found that not even min_allocation_size is allocatable. Return it 281 // anyway. There is no point to search for a better value any more. 282 *limit = min_allocation_size; 283 } else { 284 // perform the binary search. 285 julong lower_limit = min_allocation_size; 286 while ((upper_limit - lower_limit) > min_allocation_size) { 287 julong temp_limit = ((upper_limit - lower_limit) / 2) + lower_limit; 288 temp_limit = align_size_down_(temp_limit, min_allocation_size); 289 if (is_allocatable(temp_limit)) { 290 lower_limit = temp_limit; 291 } else { 292 upper_limit = temp_limit; 293 } 294 } 295 *limit = lower_limit; 296 } 297 return true; 298 #endif 299 } 300 301 const char* os::get_current_directory(char *buf, size_t buflen) { 302 return getcwd(buf, buflen); 303 } 304 305 FILE* os::open(int fd, const char* mode) { 306 return ::fdopen(fd, mode); 307 } 308 309 // Builds a platform dependent Agent_OnLoad_<lib_name> function name 310 // which is used to find statically linked in agents. 311 // Parameters: 312 // sym_name: Symbol in library we are looking for 313 // lib_name: Name of library to look in, NULL for shared libs. 314 // is_absolute_path == true if lib_name is absolute path to agent 315 // such as "/a/b/libL.so" 316 // == false if only the base name of the library is passed in 317 // such as "L" 318 char* os::build_agent_function_name(const char *sym_name, const char *lib_name, 319 bool is_absolute_path) { 320 char *agent_entry_name; 321 size_t len; 322 size_t name_len; 323 size_t prefix_len = strlen(JNI_LIB_PREFIX); 324 size_t suffix_len = strlen(JNI_LIB_SUFFIX); 325 const char *start; 326 327 if (lib_name != NULL) { 328 len = name_len = strlen(lib_name); 329 if (is_absolute_path) { 330 // Need to strip path, prefix and suffix 331 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) { 332 lib_name = ++start; 333 } 334 if (len <= (prefix_len + suffix_len)) { 335 return NULL; 336 } 337 lib_name += prefix_len; 338 name_len = strlen(lib_name) - suffix_len; 339 } 340 } 341 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2; 342 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread); 343 if (agent_entry_name == NULL) { 344 return NULL; 345 } 346 strcpy(agent_entry_name, sym_name); 347 if (lib_name != NULL) { 348 strcat(agent_entry_name, "_"); 349 strncat(agent_entry_name, lib_name, name_len); 350 } 351 return agent_entry_name; 352 } 353 354 int os::sleep(Thread* thread, jlong millis, bool interruptible) { 355 assert(thread == Thread::current(), "thread consistency check"); 356 357 ParkEvent * const slp = thread->_SleepEvent ; 358 slp->reset() ; 359 OrderAccess::fence() ; 360 361 if (interruptible) { 362 jlong prevtime = javaTimeNanos(); 363 364 for (;;) { 365 if (os::is_interrupted(thread, true)) { 366 return OS_INTRPT; 367 } 368 369 jlong newtime = javaTimeNanos(); 370 371 if (newtime - prevtime < 0) { 372 // time moving backwards, should only happen if no monotonic clock 373 // not a guarantee() because JVM should not abort on kernel/glibc bugs 374 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected in os::sleep(interruptible)"); 375 } else { 376 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 377 } 378 379 if (millis <= 0) { 380 return OS_OK; 381 } 382 383 prevtime = newtime; 384 385 { 386 assert(thread->is_Java_thread(), "sanity check"); 387 JavaThread *jt = (JavaThread *) thread; 388 ThreadBlockInVM tbivm(jt); 389 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 390 391 jt->set_suspend_equivalent(); 392 // cleared by handle_special_suspend_equivalent_condition() or 393 // java_suspend_self() via check_and_wait_while_suspended() 394 395 slp->park(millis); 396 397 // were we externally suspended while we were waiting? 398 jt->check_and_wait_while_suspended(); 399 } 400 } 401 } else { 402 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 403 jlong prevtime = javaTimeNanos(); 404 405 for (;;) { 406 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 407 // the 1st iteration ... 408 jlong newtime = javaTimeNanos(); 409 410 if (newtime - prevtime < 0) { 411 // time moving backwards, should only happen if no monotonic clock 412 // not a guarantee() because JVM should not abort on kernel/glibc bugs 413 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected on os::sleep(!interruptible)"); 414 } else { 415 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 416 } 417 418 if (millis <= 0) break ; 419 420 prevtime = newtime; 421 slp->park(millis); 422 } 423 return OS_OK ; 424 } 425 } 426 427 //////////////////////////////////////////////////////////////////////////////// 428 // interrupt support 429 430 void os::interrupt(Thread* thread) { 431 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 432 "possibility of dangling Thread pointer"); 433 434 OSThread* osthread = thread->osthread(); 435 436 if (!osthread->interrupted()) { 437 osthread->set_interrupted(true); 438 // More than one thread can get here with the same value of osthread, 439 // resulting in multiple notifications. We do, however, want the store 440 // to interrupted() to be visible to other threads before we execute unpark(). 441 OrderAccess::fence(); 442 ParkEvent * const slp = thread->_SleepEvent ; 443 if (slp != NULL) slp->unpark() ; 444 } 445 446 // For JSR166. Unpark even if interrupt status already was set 447 if (thread->is_Java_thread()) 448 ((JavaThread*)thread)->parker()->unpark(); 449 450 ParkEvent * ev = thread->_ParkEvent ; 451 if (ev != NULL) ev->unpark() ; 452 453 } 454 455 bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 456 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 457 "possibility of dangling Thread pointer"); 458 459 OSThread* osthread = thread->osthread(); 460 461 bool interrupted = osthread->interrupted(); 462 463 // NOTE that since there is no "lock" around the interrupt and 464 // is_interrupted operations, there is the possibility that the 465 // interrupted flag (in osThread) will be "false" but that the 466 // low-level events will be in the signaled state. This is 467 // intentional. The effect of this is that Object.wait() and 468 // LockSupport.park() will appear to have a spurious wakeup, which 469 // is allowed and not harmful, and the possibility is so rare that 470 // it is not worth the added complexity to add yet another lock. 471 // For the sleep event an explicit reset is performed on entry 472 // to os::sleep, so there is no early return. It has also been 473 // recommended not to put the interrupted flag into the "event" 474 // structure because it hides the issue. 475 if (interrupted && clear_interrupted) { 476 osthread->set_interrupted(false); 477 // consider thread->_SleepEvent->reset() ... optional optimization 478 } 479 480 return interrupted; 481 } 482 483 // Returned string is a constant. For unknown signals "UNKNOWN" is returned. 484 const char* os::Posix::get_signal_name(int sig, char* out, size_t outlen) { 485 486 static const struct { 487 int sig; const char* name; 488 } 489 info[] = 490 { 491 { SIGABRT, "SIGABRT" }, 492 #ifdef SIGAIO 493 { SIGAIO, "SIGAIO" }, 494 #endif 495 { SIGALRM, "SIGALRM" }, 496 #ifdef SIGALRM1 497 { SIGALRM1, "SIGALRM1" }, 498 #endif 499 { SIGBUS, "SIGBUS" }, 500 #ifdef SIGCANCEL 501 { SIGCANCEL, "SIGCANCEL" }, 502 #endif 503 { SIGCHLD, "SIGCHLD" }, 504 #ifdef SIGCLD 505 { SIGCLD, "SIGCLD" }, 506 #endif 507 { SIGCONT, "SIGCONT" }, 508 #ifdef SIGCPUFAIL 509 { SIGCPUFAIL, "SIGCPUFAIL" }, 510 #endif 511 #ifdef SIGDANGER 512 { SIGDANGER, "SIGDANGER" }, 513 #endif 514 #ifdef SIGDIL 515 { SIGDIL, "SIGDIL" }, 516 #endif 517 #ifdef SIGEMT 518 { SIGEMT, "SIGEMT" }, 519 #endif 520 { SIGFPE, "SIGFPE" }, 521 #ifdef SIGFREEZE 522 { SIGFREEZE, "SIGFREEZE" }, 523 #endif 524 #ifdef SIGGFAULT 525 { SIGGFAULT, "SIGGFAULT" }, 526 #endif 527 #ifdef SIGGRANT 528 { SIGGRANT, "SIGGRANT" }, 529 #endif 530 { SIGHUP, "SIGHUP" }, 531 { SIGILL, "SIGILL" }, 532 { SIGINT, "SIGINT" }, 533 #ifdef SIGIO 534 { SIGIO, "SIGIO" }, 535 #endif 536 #ifdef SIGIOINT 537 { SIGIOINT, "SIGIOINT" }, 538 #endif 539 #ifdef SIGIOT 540 // SIGIOT is there for BSD compatibility, but on most Unices just a 541 // synonym for SIGABRT. The result should be "SIGABRT", not 542 // "SIGIOT". 543 #if (SIGIOT != SIGABRT ) 544 { SIGIOT, "SIGIOT" }, 545 #endif 546 #endif 547 #ifdef SIGKAP 548 { SIGKAP, "SIGKAP" }, 549 #endif 550 { SIGKILL, "SIGKILL" }, 551 #ifdef SIGLOST 552 { SIGLOST, "SIGLOST" }, 553 #endif 554 #ifdef SIGLWP 555 { SIGLWP, "SIGLWP" }, 556 #endif 557 #ifdef SIGLWPTIMER 558 { SIGLWPTIMER, "SIGLWPTIMER" }, 559 #endif 560 #ifdef SIGMIGRATE 561 { SIGMIGRATE, "SIGMIGRATE" }, 562 #endif 563 #ifdef SIGMSG 564 { SIGMSG, "SIGMSG" }, 565 #endif 566 { SIGPIPE, "SIGPIPE" }, 567 #ifdef SIGPOLL 568 { SIGPOLL, "SIGPOLL" }, 569 #endif 570 #ifdef SIGPRE 571 { SIGPRE, "SIGPRE" }, 572 #endif 573 { SIGPROF, "SIGPROF" }, 574 #ifdef SIGPTY 575 { SIGPTY, "SIGPTY" }, 576 #endif 577 #ifdef SIGPWR 578 { SIGPWR, "SIGPWR" }, 579 #endif 580 { SIGQUIT, "SIGQUIT" }, 581 #ifdef SIGRECONFIG 582 { SIGRECONFIG, "SIGRECONFIG" }, 583 #endif 584 #ifdef SIGRECOVERY 585 { SIGRECOVERY, "SIGRECOVERY" }, 586 #endif 587 #ifdef SIGRESERVE 588 { SIGRESERVE, "SIGRESERVE" }, 589 #endif 590 #ifdef SIGRETRACT 591 { SIGRETRACT, "SIGRETRACT" }, 592 #endif 593 #ifdef SIGSAK 594 { SIGSAK, "SIGSAK" }, 595 #endif 596 { SIGSEGV, "SIGSEGV" }, 597 #ifdef SIGSOUND 598 { SIGSOUND, "SIGSOUND" }, 599 #endif 600 { SIGSTOP, "SIGSTOP" }, 601 { SIGSYS, "SIGSYS" }, 602 #ifdef SIGSYSERROR 603 { SIGSYSERROR, "SIGSYSERROR" }, 604 #endif 605 #ifdef SIGTALRM 606 { SIGTALRM, "SIGTALRM" }, 607 #endif 608 { SIGTERM, "SIGTERM" }, 609 #ifdef SIGTHAW 610 { SIGTHAW, "SIGTHAW" }, 611 #endif 612 { SIGTRAP, "SIGTRAP" }, 613 #ifdef SIGTSTP 614 { SIGTSTP, "SIGTSTP" }, 615 #endif 616 { SIGTTIN, "SIGTTIN" }, 617 { SIGTTOU, "SIGTTOU" }, 618 #ifdef SIGURG 619 { SIGURG, "SIGURG" }, 620 #endif 621 { SIGUSR1, "SIGUSR1" }, 622 { SIGUSR2, "SIGUSR2" }, 623 #ifdef SIGVIRT 624 { SIGVIRT, "SIGVIRT" }, 625 #endif 626 { SIGVTALRM, "SIGVTALRM" }, 627 #ifdef SIGWAITING 628 { SIGWAITING, "SIGWAITING" }, 629 #endif 630 #ifdef SIGWINCH 631 { SIGWINCH, "SIGWINCH" }, 632 #endif 633 #ifdef SIGWINDOW 634 { SIGWINDOW, "SIGWINDOW" }, 635 #endif 636 { SIGXCPU, "SIGXCPU" }, 637 { SIGXFSZ, "SIGXFSZ" }, 638 #ifdef SIGXRES 639 { SIGXRES, "SIGXRES" }, 640 #endif 641 { -1, NULL } 642 }; 643 644 const char* ret = NULL; 645 646 #ifdef SIGRTMIN 647 if (sig >= SIGRTMIN && sig <= SIGRTMAX) { 648 if (sig == SIGRTMIN) { 649 ret = "SIGRTMIN"; 650 } else if (sig == SIGRTMAX) { 651 ret = "SIGRTMAX"; 652 } else { 653 jio_snprintf(out, outlen, "SIGRTMIN+%d", sig - SIGRTMIN); 654 return out; 655 } 656 } 657 #endif 658 659 if (sig > 0) { 660 for (int idx = 0; info[idx].sig != -1; idx ++) { 661 if (info[idx].sig == sig) { 662 ret = info[idx].name; 663 break; 664 } 665 } 666 } 667 668 if (!ret) { 669 if (!is_valid_signal(sig)) { 670 ret = "INVALID"; 671 } else { 672 ret = "UNKNOWN"; 673 } 674 } 675 676 if (out && outlen > 0) { 677 strncpy(out, ret, outlen); 678 out[outlen - 1] = '\0'; 679 } 680 return out; 681 } 682 683 // Returns true if signal number is valid. 684 bool os::Posix::is_valid_signal(int sig) { 685 // MacOS not really POSIX compliant: sigaddset does not return 686 // an error for invalid signal numbers. However, MacOS does not 687 // support real time signals and simply seems to have just 33 688 // signals with no holes in the signal range. 689 #ifdef __APPLE__ 690 return sig >= 1 && sig < NSIG; 691 #else 692 // Use sigaddset to check for signal validity. 693 sigset_t set; 694 if (sigaddset(&set, sig) == -1 && errno == EINVAL) { 695 return false; 696 } 697 return true; 698 #endif 699 } 700 701 #define NUM_IMPORTANT_SIGS 32 702 // Returns one-line short description of a signal set in a user provided buffer. 703 const char* os::Posix::describe_signal_set_short(const sigset_t* set, char* buffer, size_t buf_size) { 704 assert(buf_size == (NUM_IMPORTANT_SIGS + 1), "wrong buffer size"); 705 // Note: for shortness, just print out the first 32. That should 706 // cover most of the useful ones, apart from realtime signals. 707 for (int sig = 1; sig <= NUM_IMPORTANT_SIGS; sig++) { 708 const int rc = sigismember(set, sig); 709 if (rc == -1 && errno == EINVAL) { 710 buffer[sig-1] = '?'; 711 } else { 712 buffer[sig-1] = rc == 0 ? '0' : '1'; 713 } 714 } 715 buffer[NUM_IMPORTANT_SIGS] = 0; 716 return buffer; 717 } 718 719 // Prints one-line description of a signal set. 720 void os::Posix::print_signal_set_short(outputStream* st, const sigset_t* set) { 721 char buf[NUM_IMPORTANT_SIGS + 1]; 722 os::Posix::describe_signal_set_short(set, buf, sizeof(buf)); 723 st->print("%s", buf); 724 } 725 726 // Writes one-line description of a combination of sigaction.sa_flags into a user 727 // provided buffer. Returns that buffer. 728 const char* os::Posix::describe_sa_flags(int flags, char* buffer, size_t size) { 729 char* p = buffer; 730 size_t remaining = size; 731 bool first = true; 732 int idx = 0; 733 734 assert(buffer, "invalid argument"); 735 736 if (size == 0) { 737 return buffer; 738 } 739 740 strncpy(buffer, "none", size); 741 742 const struct { 743 int i; 744 const char* s; 745 } flaginfo [] = { 746 { SA_NOCLDSTOP, "SA_NOCLDSTOP" }, 747 { SA_ONSTACK, "SA_ONSTACK" }, 748 { SA_RESETHAND, "SA_RESETHAND" }, 749 { SA_RESTART, "SA_RESTART" }, 750 { SA_SIGINFO, "SA_SIGINFO" }, 751 { SA_NOCLDWAIT, "SA_NOCLDWAIT" }, 752 { SA_NODEFER, "SA_NODEFER" }, 753 #ifdef AIX 754 { SA_ONSTACK, "SA_ONSTACK" }, 755 { SA_OLDSTYLE, "SA_OLDSTYLE" }, 756 #endif 757 { 0, NULL } 758 }; 759 760 for (idx = 0; flaginfo[idx].s && remaining > 1; idx++) { 761 if (flags & flaginfo[idx].i) { 762 if (first) { 763 jio_snprintf(p, remaining, "%s", flaginfo[idx].s); 764 first = false; 765 } else { 766 jio_snprintf(p, remaining, "|%s", flaginfo[idx].s); 767 } 768 const size_t len = strlen(p); 769 p += len; 770 remaining -= len; 771 } 772 } 773 774 buffer[size - 1] = '\0'; 775 776 return buffer; 777 } 778 779 // Prints one-line description of a combination of sigaction.sa_flags. 780 void os::Posix::print_sa_flags(outputStream* st, int flags) { 781 char buffer[0x100]; 782 os::Posix::describe_sa_flags(flags, buffer, sizeof(buffer)); 783 st->print("%s", buffer); 784 } 785 786 // Helper function for os::Posix::print_siginfo_...(): 787 // return a textual description for signal code. 788 struct enum_sigcode_desc_t { 789 const char* s_name; 790 const char* s_desc; 791 }; 792 793 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) { 794 795 const struct { 796 int sig; int code; const char* s_code; const char* s_desc; 797 } t1 [] = { 798 { SIGILL, ILL_ILLOPC, "ILL_ILLOPC", "Illegal opcode." }, 799 { SIGILL, ILL_ILLOPN, "ILL_ILLOPN", "Illegal operand." }, 800 { SIGILL, ILL_ILLADR, "ILL_ILLADR", "Illegal addressing mode." }, 801 { SIGILL, ILL_ILLTRP, "ILL_ILLTRP", "Illegal trap." }, 802 { SIGILL, ILL_PRVOPC, "ILL_PRVOPC", "Privileged opcode." }, 803 { SIGILL, ILL_PRVREG, "ILL_PRVREG", "Privileged register." }, 804 { SIGILL, ILL_COPROC, "ILL_COPROC", "Coprocessor error." }, 805 { SIGILL, ILL_BADSTK, "ILL_BADSTK", "Internal stack error." }, 806 #if defined(IA64) && defined(LINUX) 807 { SIGILL, ILL_BADIADDR, "ILL_BADIADDR", "Unimplemented instruction address" }, 808 { SIGILL, ILL_BREAK, "ILL_BREAK", "Application Break instruction" }, 809 #endif 810 { SIGFPE, FPE_INTDIV, "FPE_INTDIV", "Integer divide by zero." }, 811 { SIGFPE, FPE_INTOVF, "FPE_INTOVF", "Integer overflow." }, 812 { SIGFPE, FPE_FLTDIV, "FPE_FLTDIV", "Floating-point divide by zero." }, 813 { SIGFPE, FPE_FLTOVF, "FPE_FLTOVF", "Floating-point overflow." }, 814 { SIGFPE, FPE_FLTUND, "FPE_FLTUND", "Floating-point underflow." }, 815 { SIGFPE, FPE_FLTRES, "FPE_FLTRES", "Floating-point inexact result." }, 816 { SIGFPE, FPE_FLTINV, "FPE_FLTINV", "Invalid floating-point operation." }, 817 { SIGFPE, FPE_FLTSUB, "FPE_FLTSUB", "Subscript out of range." }, 818 { SIGSEGV, SEGV_MAPERR, "SEGV_MAPERR", "Address not mapped to object." }, 819 { SIGSEGV, SEGV_ACCERR, "SEGV_ACCERR", "Invalid permissions for mapped object." }, 820 #ifdef AIX 821 // no explanation found what keyerr would be 822 { SIGSEGV, SEGV_KEYERR, "SEGV_KEYERR", "key error" }, 823 #endif 824 #if defined(IA64) && !defined(AIX) 825 { SIGSEGV, SEGV_PSTKOVF, "SEGV_PSTKOVF", "Paragraph stack overflow" }, 826 #endif 827 { SIGBUS, BUS_ADRALN, "BUS_ADRALN", "Invalid address alignment." }, 828 { SIGBUS, BUS_ADRERR, "BUS_ADRERR", "Nonexistent physical address." }, 829 { SIGBUS, BUS_OBJERR, "BUS_OBJERR", "Object-specific hardware error." }, 830 { SIGTRAP, TRAP_BRKPT, "TRAP_BRKPT", "Process breakpoint." }, 831 { SIGTRAP, TRAP_TRACE, "TRAP_TRACE", "Process trace trap." }, 832 { SIGCHLD, CLD_EXITED, "CLD_EXITED", "Child has exited." }, 833 { SIGCHLD, CLD_KILLED, "CLD_KILLED", "Child has terminated abnormally and did not create a core file." }, 834 { SIGCHLD, CLD_DUMPED, "CLD_DUMPED", "Child has terminated abnormally and created a core file." }, 835 { SIGCHLD, CLD_TRAPPED, "CLD_TRAPPED", "Traced child has trapped." }, 836 { SIGCHLD, CLD_STOPPED, "CLD_STOPPED", "Child has stopped." }, 837 { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." }, 838 #ifdef SIGPOLL 839 { SIGPOLL, POLL_OUT, "POLL_OUT", "Output buffers available." }, 840 { SIGPOLL, POLL_MSG, "POLL_MSG", "Input message available." }, 841 { SIGPOLL, POLL_ERR, "POLL_ERR", "I/O error." }, 842 { SIGPOLL, POLL_PRI, "POLL_PRI", "High priority input available." }, 843 { SIGPOLL, POLL_HUP, "POLL_HUP", "Device disconnected. [Option End]" }, 844 #endif 845 { -1, -1, NULL, NULL } 846 }; 847 848 // Codes valid in any signal context. 849 const struct { 850 int code; const char* s_code; const char* s_desc; 851 } t2 [] = { 852 { SI_USER, "SI_USER", "Signal sent by kill()." }, 853 { SI_QUEUE, "SI_QUEUE", "Signal sent by the sigqueue()." }, 854 { SI_TIMER, "SI_TIMER", "Signal generated by expiration of a timer set by timer_settime()." }, 855 { SI_ASYNCIO, "SI_ASYNCIO", "Signal generated by completion of an asynchronous I/O request." }, 856 { SI_MESGQ, "SI_MESGQ", "Signal generated by arrival of a message on an empty message queue." }, 857 // Linux specific 858 #ifdef SI_TKILL 859 { SI_TKILL, "SI_TKILL", "Signal sent by tkill (pthread_kill)" }, 860 #endif 861 #ifdef SI_DETHREAD 862 { SI_DETHREAD, "SI_DETHREAD", "Signal sent by execve() killing subsidiary threads" }, 863 #endif 864 #ifdef SI_KERNEL 865 { SI_KERNEL, "SI_KERNEL", "Signal sent by kernel." }, 866 #endif 867 #ifdef SI_SIGIO 868 { SI_SIGIO, "SI_SIGIO", "Signal sent by queued SIGIO" }, 869 #endif 870 871 #ifdef AIX 872 { SI_UNDEFINED, "SI_UNDEFINED","siginfo contains partial information" }, 873 { SI_EMPTY, "SI_EMPTY", "siginfo contains no useful information" }, 874 #endif 875 876 #ifdef __sun 877 { SI_NOINFO, "SI_NOINFO", "No signal information" }, 878 { SI_RCTL, "SI_RCTL", "kernel generated signal via rctl action" }, 879 { SI_LWP, "SI_LWP", "Signal sent via lwp_kill" }, 880 #endif 881 882 { -1, NULL, NULL } 883 }; 884 885 const char* s_code = NULL; 886 const char* s_desc = NULL; 887 888 for (int i = 0; t1[i].sig != -1; i ++) { 889 if (t1[i].sig == si->si_signo && t1[i].code == si->si_code) { 890 s_code = t1[i].s_code; 891 s_desc = t1[i].s_desc; 892 break; 893 } 894 } 895 896 if (s_code == NULL) { 897 for (int i = 0; t2[i].s_code != NULL; i ++) { 898 if (t2[i].code == si->si_code) { 899 s_code = t2[i].s_code; 900 s_desc = t2[i].s_desc; 901 } 902 } 903 } 904 905 if (s_code == NULL) { 906 out->s_name = "unknown"; 907 out->s_desc = "unknown"; 908 return false; 909 } 910 911 out->s_name = s_code; 912 out->s_desc = s_desc; 913 914 return true; 915 } 916 917 // A POSIX conform, platform-independend siginfo print routine. 918 // Short print out on one line. 919 void os::Posix::print_siginfo_brief(outputStream* os, const siginfo_t* si) { 920 char buf[20]; 921 os->print("siginfo: "); 922 923 if (!si) { 924 os->print("<null>"); 925 return; 926 } 927 928 // See print_siginfo_full() for details. 929 const int sig = si->si_signo; 930 931 os->print("si_signo: %d (%s)", sig, os::Posix::get_signal_name(sig, buf, sizeof(buf))); 932 933 enum_sigcode_desc_t ed; 934 if (get_signal_code_description(si, &ed)) { 935 os->print(", si_code: %d (%s)", si->si_code, ed.s_name); 936 } else { 937 os->print(", si_code: %d (unknown)", si->si_code); 938 } 939 940 if (si->si_errno) { 941 os->print(", si_errno: %d", si->si_errno); 942 } 943 944 const int me = (int) ::getpid(); 945 const int pid = (int) si->si_pid; 946 947 if (si->si_code == SI_USER || si->si_code == SI_QUEUE) { 948 if (IS_VALID_PID(pid) && pid != me) { 949 os->print(", sent from pid: %d (uid: %d)", pid, (int) si->si_uid); 950 } 951 } else if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || 952 sig == SIGTRAP || sig == SIGFPE) { 953 os->print(", si_addr: " PTR_FORMAT, si->si_addr); 954 #ifdef SIGPOLL 955 } else if (sig == SIGPOLL) { 956 os->print(", si_band: " PTR64_FORMAT, (uint64_t)si->si_band); 957 #endif 958 } else if (sig == SIGCHLD) { 959 os->print_cr(", si_pid: %d, si_uid: %d, si_status: %d", (int) si->si_pid, si->si_uid, si->si_status); 960 } 961 } 962 963 os::WatcherThreadCrashProtection::WatcherThreadCrashProtection() { 964 assert(Thread::current()->is_Watcher_thread(), "Must be WatcherThread"); 965 } 966 967 /* 968 * See the caveats for this class in os_posix.hpp 969 * Protects the callback call so that SIGSEGV / SIGBUS jumps back into this 970 * method and returns false. If none of the signals are raised, returns true. 971 * The callback is supposed to provide the method that should be protected. 972 */ 973 bool os::WatcherThreadCrashProtection::call(os::CrashProtectionCallback& cb) { 974 sigset_t saved_sig_mask; 975 976 assert(Thread::current()->is_Watcher_thread(), "Only for WatcherThread"); 977 assert(!WatcherThread::watcher_thread()->has_crash_protection(), 978 "crash_protection already set?"); 979 980 // we cannot rely on sigsetjmp/siglongjmp to save/restore the signal mask 981 // since on at least some systems (OS X) siglongjmp will restore the mask 982 // for the process, not the thread 983 pthread_sigmask(0, NULL, &saved_sig_mask); 984 if (sigsetjmp(_jmpbuf, 0) == 0) { 985 // make sure we can see in the signal handler that we have crash protection 986 // installed 987 WatcherThread::watcher_thread()->set_crash_protection(this); 988 cb.call(); 989 // and clear the crash protection 990 WatcherThread::watcher_thread()->set_crash_protection(NULL); 991 return true; 992 } 993 // this happens when we siglongjmp() back 994 pthread_sigmask(SIG_SETMASK, &saved_sig_mask, NULL); 995 WatcherThread::watcher_thread()->set_crash_protection(NULL); 996 return false; 997 } 998 999 void os::WatcherThreadCrashProtection::restore() { 1000 assert(WatcherThread::watcher_thread()->has_crash_protection(), 1001 "must have crash protection"); 1002 1003 siglongjmp(_jmpbuf, 1); 1004 } 1005 1006 void os::WatcherThreadCrashProtection::check_crash_protection(int sig, 1007 Thread* thread) { 1008 1009 if (thread != NULL && 1010 thread->is_Watcher_thread() && 1011 WatcherThread::watcher_thread()->has_crash_protection()) { 1012 1013 if (sig == SIGSEGV || sig == SIGBUS) { 1014 WatcherThread::watcher_thread()->crash_protection()->restore(); 1015 } 1016 } 1017 }