libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc

   1 //===-- sanitizer_linux_libcdep.cc ----------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is shared between AddressSanitizer and ThreadSanitizer
   9 // run-time libraries and implements linux-specific functions from
  10 // sanitizer_libc.h.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_platform.h"
  14
  15 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
  16
  17 #include "sanitizer_allocator_internal.h"
  18 #include "sanitizer_atomic.h"
  19 #include "sanitizer_common.h"
  20 #include "sanitizer_file.h"
  21 #include "sanitizer_flags.h"
  22 #include "sanitizer_freebsd.h"
  23 #include "sanitizer_linux.h"
  24 #include "sanitizer_placement_new.h"
  25 #include "sanitizer_procmaps.h"
  26 #include "sanitizer_stacktrace.h"
  27
  28 #include <dlfcn.h>  // for dlsym()
  29 #include <link.h>
  30 #include <pthread.h>
  31 #include <signal.h>
  32 #include <sys/resource.h>
  33 #include <syslog.h>
  34
  35 #if SANITIZER_FREEBSD
  36 #include <pthread_np.h>
  37 #include <osreldate.h>
  38 #define pthread_getattr_np pthread_attr_get_np
  39 #endif
  40
  41 #if SANITIZER_LINUX
  42 #include <sys/prctl.h>
  43 #endif
  44
  45 #if SANITIZER_ANDROID
  46 #include <android/api-level.h>
  47 #endif
  48
  49 #if SANITIZER_ANDROID && __ANDROID_API__ < 21
  50 #include <android/log.h>
  51 #endif
  52
  53 #if !SANITIZER_ANDROID
  54 #include <elf.h>
  55 #include <unistd.h>
  56 #endif
  57
  58 namespace __sanitizer {
  59
  60 SANITIZER_WEAK_ATTRIBUTE int
  61 real_sigaction(int signum, const void *act, void *oldact);
  62
  63 int internal_sigaction(int signum, const void *act, void *oldact) {
  64 #if !SANITIZER_GO
  65   if (&real_sigaction)
  66     return real_sigaction(signum, act, oldact);
  67 #endif
  68   return sigaction(signum, (const struct sigaction *)act,
  69                    (struct sigaction *)oldact);
  70 }
  71
  72 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
  73                                 uptr *stack_bottom) {
  74   CHECK(stack_top);
  75   CHECK(stack_bottom);
  76   if (at_initialization) {
  77     // This is the main thread. Libpthread may not be initialized yet.
  78     struct rlimit rl;
  79     CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
  80
  81     // Find the mapping that contains a stack variable.
  82     MemoryMappingLayout proc_maps(/*cache_enabled*/true);
  83     MemoryMappedSegment segment;
  84     uptr prev_end = 0;
  85     while (proc_maps.Next(&segment)) {
  86       if ((uptr)&rl < segment.end) break;
  87       prev_end = segment.end;
  88     }
  89     CHECK((uptr)&rl >= segment.start && (uptr)&rl < segment.end);
  90
  91     // Get stacksize from rlimit, but clip it so that it does not overlap
  92     // with other mappings.
  93     uptr stacksize = rl.rlim_cur;
  94     if (stacksize > segment.end - prev_end) stacksize = segment.end - prev_end;
  95     // When running with unlimited stack size, we still want to set some limit.
  96     // The unlimited stack size is caused by 'ulimit -s unlimited'.
  97     // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
  98     if (stacksize > kMaxThreadStackSize)
  99       stacksize = kMaxThreadStackSize;
 100     *stack_top = segment.end;
 101     *stack_bottom = segment.end - stacksize;
 102     return;
 103   }
 104   pthread_attr_t attr;
 105   pthread_attr_init(&attr);
 106   CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
 107   uptr stacksize = 0;
 108   void *stackaddr = nullptr;
 109   my_pthread_attr_getstack(&attr, &stackaddr, &stacksize);
 110   pthread_attr_destroy(&attr);
 111
 112   *stack_top = (uptr)stackaddr + stacksize;
 113   *stack_bottom = (uptr)stackaddr;
 114 }
 115
 116 #if !SANITIZER_GO
 117 bool SetEnv(const char *name, const char *value) {
 118   void *f = dlsym(RTLD_NEXT, "setenv");
 119   if (!f)
 120     return false;
 121   typedef int(*setenv_ft)(const char *name, const char *value, int overwrite);
 122   setenv_ft setenv_f;
 123   CHECK_EQ(sizeof(setenv_f), sizeof(f));
 124   internal_memcpy(&setenv_f, &f, sizeof(f));
 125   return setenv_f(name, value, 1) == 0;
 126 }
 127 #endif
 128
 129 bool SanitizerSetThreadName(const char *name) {
 130 #ifdef PR_SET_NAME
 131   return 0 == prctl(PR_SET_NAME, (unsigned long)name, 0, 0, 0);  // NOLINT
 132 #else
 133   return false;
 134 #endif
 135 }
 136
 137 bool SanitizerGetThreadName(char *name, int max_len) {
 138 #ifdef PR_GET_NAME
 139   char buff[17];
 140   if (prctl(PR_GET_NAME, (unsigned long)buff, 0, 0, 0))  // NOLINT
 141     return false;
 142   internal_strncpy(name, buff, max_len);
 143   name[max_len] = 0;
 144   return true;
 145 #else
 146   return false;
 147 #endif
 148 }
 149
 150 #if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && \
 151     !SANITIZER_NETBSD
 152 static uptr g_tls_size;
 153
 154 #ifdef __i386__
 155 # define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall))
 156 #else
 157 # define DL_INTERNAL_FUNCTION
 158 #endif
 159
 160 void InitTlsSize() {
 161 // all current supported platforms have 16 bytes stack alignment
 162   const size_t kStackAlign = 16;
 163   typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION;
 164   get_tls_func get_tls;
 165   void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
 166   CHECK_EQ(sizeof(get_tls), sizeof(get_tls_static_info_ptr));
 167   internal_memcpy(&get_tls, &get_tls_static_info_ptr,
 168                   sizeof(get_tls_static_info_ptr));
 169   CHECK_NE(get_tls, 0);
 170   size_t tls_size = 0;
 171   size_t tls_align = 0;
 172   get_tls(&tls_size, &tls_align);
 173   if (tls_align < kStackAlign)
 174     tls_align = kStackAlign;
 175   g_tls_size = RoundUpTo(tls_size, tls_align);
 176 }
 177 #else
 178 void InitTlsSize() { }
 179 #endif  // !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO &&
 180         // !SANITIZER_NETBSD
 181
 182 #if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) \
 183     || defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__) \
 184     || defined(__arm__)) && SANITIZER_LINUX && !SANITIZER_ANDROID
 185 // sizeof(struct pthread) from glibc.
 186 static atomic_uintptr_t kThreadDescriptorSize;
 187
 188 uptr ThreadDescriptorSize() {
 189   uptr val = atomic_load(&kThreadDescriptorSize, memory_order_relaxed);
 190   if (val)
 191     return val;
 192 #if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
 193 #ifdef _CS_GNU_LIBC_VERSION
 194   char buf[64];
 195   uptr len = confstr(_CS_GNU_LIBC_VERSION, buf, sizeof(buf));
 196   if (len < sizeof(buf) && internal_strncmp(buf, "glibc 2.", 8) == 0) {
 197     char *end;
 198     int minor = internal_simple_strtoll(buf + 8, &end, 10);
 199     if (end != buf + 8 && (*end == '\0' || *end == '.' || *end == '-')) {
 200       int patch = 0;
 201       if (*end == '.')
 202         // strtoll will return 0 if no valid conversion could be performed
 203         patch = internal_simple_strtoll(end + 1, nullptr, 10);
 204
 205       /* sizeof(struct pthread) values from various glibc versions.  */
 206       if (SANITIZER_X32)
 207         val = 1728;  // Assume only one particular version for x32.
 208       // For ARM sizeof(struct pthread) changed in Glibc 2.23.
 209       else if (SANITIZER_ARM)
 210         val = minor <= 22 ? 1120 : 1216;
 211       else if (minor <= 3)
 212         val = FIRST_32_SECOND_64(1104, 1696);
 213       else if (minor == 4)
 214         val = FIRST_32_SECOND_64(1120, 1728);
 215       else if (minor == 5)
 216         val = FIRST_32_SECOND_64(1136, 1728);
 217       else if (minor <= 9)
 218         val = FIRST_32_SECOND_64(1136, 1712);
 219       else if (minor == 10)
 220         val = FIRST_32_SECOND_64(1168, 1776);
 221       else if (minor == 11 || (minor == 12 && patch == 1))
 222         val = FIRST_32_SECOND_64(1168, 2288);
 223       else if (minor <= 13)
 224         val = FIRST_32_SECOND_64(1168, 2304);
 225       else
 226         val = FIRST_32_SECOND_64(1216, 2304);
 227     }
 228     if (val)
 229       atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 230     return val;
 231   }
 232 #endif
 233 #elif defined(__mips__)
 234   // TODO(sagarthakur): add more values as per different glibc versions.
 235   val = FIRST_32_SECOND_64(1152, 1776);
 236   if (val)
 237     atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 238   return val;
 239 #elif defined(__aarch64__)
 240   // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22.
 241   val = 1776;
 242   atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 243   return val;
 244 #elif defined(__powerpc64__)
 245   val = 1776; // from glibc.ppc64le 2.20-8.fc21
 246   atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 247   return val;
 248 #elif defined(__s390__)
 249   val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
 250   atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 251 #endif
 252   return 0;
 253 }
 254
 255 // The offset at which pointer to self is located in the thread descriptor.
 256 const uptr kThreadSelfOffset = FIRST_32_SECOND_64(8, 16);
 257
 258 uptr ThreadSelfOffset() {
 259   return kThreadSelfOffset;
 260 }
 261
 262 #if defined(__mips__) || defined(__powerpc64__)
 263 // TlsPreTcbSize includes size of struct pthread_descr and size of tcb
 264 // head structure. It lies before the static tls blocks.
 265 static uptr TlsPreTcbSize() {
 266 # if defined(__mips__)
 267   const uptr kTcbHead = 16; // sizeof (tcbhead_t)
 268 # elif defined(__powerpc64__)
 269   const uptr kTcbHead = 88; // sizeof (tcbhead_t)
 270 # endif
 271   const uptr kTlsAlign = 16;
 272   const uptr kTlsPreTcbSize =
 273       RoundUpTo(ThreadDescriptorSize() + kTcbHead, kTlsAlign);
 274   return kTlsPreTcbSize;
 275 }
 276 #endif
 277
 278 uptr ThreadSelf() {
 279   uptr descr_addr;
 280 # if defined(__i386__)
 281   asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
 282 # elif defined(__x86_64__)
 283   asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
 284 # elif defined(__mips__)
 285   // MIPS uses TLS variant I. The thread pointer (in hardware register $29)
 286   // points to the end of the TCB + 0x7000. The pthread_descr structure is
 287   // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
 288   // TCB and the size of pthread_descr.
 289   const uptr kTlsTcbOffset = 0x7000;
 290   uptr thread_pointer;
 291   asm volatile(".set push;\
 292                 .set mips64r2;\
 293                 rdhwr %0,$29;\
 294                 .set pop" : "=r" (thread_pointer));
 295   descr_addr = thread_pointer - kTlsTcbOffset - TlsPreTcbSize();
 296 # elif defined(__aarch64__) || defined(__arm__)
 297   descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
 298                                       ThreadDescriptorSize();
 299 # elif defined(__s390__)
 300   descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer());
 301 # elif defined(__powerpc64__)
 302   // PPC64LE uses TLS variant I. The thread pointer (in GPR 13)
 303   // points to the end of the TCB + 0x7000. The pthread_descr structure is
 304   // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
 305   // TCB and the size of pthread_descr.
 306   const uptr kTlsTcbOffset = 0x7000;
 307   uptr thread_pointer;
 308   asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset));
 309   descr_addr = thread_pointer - TlsPreTcbSize();
 310 # else
 311 #  error "unsupported CPU arch"
 312 # endif
 313   return descr_addr;
 314 }
 315 #endif  // (x86_64 || i386 || MIPS) && SANITIZER_LINUX
 316
 317 #if SANITIZER_FREEBSD
 318 static void **ThreadSelfSegbase() {
 319   void **segbase = 0;
 320 # if defined(__i386__)
 321   // sysarch(I386_GET_GSBASE, segbase);
 322   __asm __volatile("mov %%gs:0, %0" : "=r" (segbase));
 323 # elif defined(__x86_64__)
 324   // sysarch(AMD64_GET_FSBASE, segbase);
 325   __asm __volatile("movq %%fs:0, %0" : "=r" (segbase));
 326 # else
 327 #  error "unsupported CPU arch for FreeBSD platform"
 328 # endif
 329   return segbase;
 330 }
 331
 332 uptr ThreadSelf() {
 333   return (uptr)ThreadSelfSegbase()[2];
 334 }
 335 #elif SANITIZER_NETBSD
 336 uptr ThreadSelf() { return (uptr)pthread_self(); }
 337 #endif  // SANITIZER_NETBSD
 338
 339 #if !SANITIZER_GO
 340 static void GetTls(uptr *addr, uptr *size) {
 341 #if SANITIZER_LINUX && !SANITIZER_ANDROID
 342 # if defined(__x86_64__) || defined(__i386__) || defined(__s390__)
 343   *addr = ThreadSelf();
 344   *size = GetTlsSize();
 345   *addr -= *size;
 346   *addr += ThreadDescriptorSize();
 347 # elif defined(__mips__) || defined(__aarch64__) || defined(__powerpc64__) \
 348     || defined(__arm__)
 349   *addr = ThreadSelf();
 350   *size = GetTlsSize();
 351 # else
 352   *addr = 0;
 353   *size = 0;
 354 # endif
 355 #elif SANITIZER_FREEBSD
 356   void** segbase = ThreadSelfSegbase();
 357   *addr = 0;
 358   *size = 0;
 359   if (segbase != 0) {
 360     // tcbalign = 16
 361     // tls_size = round(tls_static_space, tcbalign);
 362     // dtv = segbase[1];
 363     // dtv[2] = segbase - tls_static_space;
 364     void **dtv = (void**) segbase[1];
 365     *addr = (uptr) dtv[2];
 366     *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]);
 367   }
 368 #elif SANITIZER_ANDROID || SANITIZER_NETBSD
 369   *addr = 0;
 370   *size = 0;
 371 #else
 372 # error "Unknown OS"
 373 #endif
 374 }
 375 #endif
 376
 377 #if !SANITIZER_GO
 378 uptr GetTlsSize() {
 379 #if SANITIZER_FREEBSD || SANITIZER_ANDROID || SANITIZER_NETBSD
 380   uptr addr, size;
 381   GetTls(&addr, &size);
 382   return size;
 383 #elif defined(__mips__) || defined(__powerpc64__)
 384   return RoundUpTo(g_tls_size + TlsPreTcbSize(), 16);
 385 #else
 386   return g_tls_size;
 387 #endif
 388 }
 389 #endif
 390
 391 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
 392                           uptr *tls_addr, uptr *tls_size) {
 393 #if SANITIZER_GO
 394   // Stub implementation for Go.
 395   *stk_addr = *stk_size = *tls_addr = *tls_size = 0;
 396 #else
 397   GetTls(tls_addr, tls_size);
 398
 399   uptr stack_top, stack_bottom;
 400   GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
 401   *stk_addr = stack_bottom;
 402   *stk_size = stack_top - stack_bottom;
 403
 404   if (!main) {
 405     // If stack and tls intersect, make them non-intersecting.
 406     if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) {
 407       CHECK_GT(*tls_addr + *tls_size, *stk_addr);
 408       CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size);
 409       *stk_size -= *tls_size;
 410       *tls_addr = *stk_addr + *stk_size;
 411     }
 412   }
 413 #endif
 414 }
 415
 416 # if !SANITIZER_FREEBSD
 417 typedef ElfW(Phdr) Elf_Phdr;
 418 # elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001  // v9.2
 419 #  define Elf_Phdr XElf32_Phdr
 420 #  define dl_phdr_info xdl_phdr_info
 421 #  define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b))
 422 # endif
 423
 424 struct DlIteratePhdrData {
 425   InternalMmapVectorNoCtor<LoadedModule> *modules;
 426   bool first;
 427 };
 428
 429 static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
 430   DlIteratePhdrData *data = (DlIteratePhdrData*)arg;
 431   InternalScopedString module_name(kMaxPathLength);
 432   if (data->first) {
 433     data->first = false;
 434     // First module is the binary itself.
 435     ReadBinaryNameCached(module_name.data(), module_name.size());
 436   } else if (info->dlpi_name) {
 437     module_name.append("%s", info->dlpi_name);
 438   }
 439   if (module_name[0] == '\0')
 440     return 0;
 441   LoadedModule cur_module;
 442   cur_module.set(module_name.data(), info->dlpi_addr);
 443   for (int i = 0; i < info->dlpi_phnum; i++) {
 444     const Elf_Phdr *phdr = &info->dlpi_phdr[i];
 445     if (phdr->p_type == PT_LOAD) {
 446       uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
 447       uptr cur_end = cur_beg + phdr->p_memsz;
 448       bool executable = phdr->p_flags & PF_X;
 449       bool writable = phdr->p_flags & PF_W;
 450       cur_module.addAddressRange(cur_beg, cur_end, executable,
 451                                  writable);
 452     }
 453   }
 454   data->modules->push_back(cur_module);
 455   return 0;
 456 }
 457
 458 #if SANITIZER_ANDROID && __ANDROID_API__ < 21
 459 extern "C" __attribute__((weak)) int dl_iterate_phdr(
 460     int (*)(struct dl_phdr_info *, size_t, void *), void *);
 461 #endif
 462
 463 static bool requiresProcmaps() {
 464 #if SANITIZER_ANDROID && __ANDROID_API__ <= 22
 465   // Fall back to /proc/maps if dl_iterate_phdr is unavailable or broken.
 466   // The runtime check allows the same library to work with
 467   // both K and L (and future) Android releases.
 468   return AndroidGetApiLevel() <= ANDROID_LOLLIPOP_MR1;
 469 #else
 470   return false;
 471 #endif
 472 }
 473
 474 static void procmapsInit(InternalMmapVectorNoCtor<LoadedModule> *modules) {
 475   MemoryMappingLayout memory_mapping(/*cache_enabled*/true);
 476   memory_mapping.DumpListOfModules(modules);
 477 }
 478
 479 void ListOfModules::init() {
 480   clearOrInit();
 481   if (requiresProcmaps()) {
 482     procmapsInit(&modules_);
 483   } else {
 484     DlIteratePhdrData data = {&modules_, true};
 485     dl_iterate_phdr(dl_iterate_phdr_cb, &data);
 486   }
 487 }
 488
 489 // When a custom loader is used, dl_iterate_phdr may not contain the full
 490 // list of modules. Allow callers to fall back to using procmaps.
 491 void ListOfModules::fallbackInit() {
 492   if (!requiresProcmaps()) {
 493     clearOrInit();
 494     procmapsInit(&modules_);
 495   } else {
 496     clear();
 497   }
 498 }
 499
 500 // getrusage does not give us the current RSS, only the max RSS.
 501 // Still, this is better than nothing if /proc/self/statm is not available
 502 // for some reason, e.g. due to a sandbox.
 503 static uptr GetRSSFromGetrusage() {
 504   struct rusage usage;
 505   if (getrusage(RUSAGE_SELF, &usage))  // Failed, probably due to a sandbox.
 506     return 0;
 507   return usage.ru_maxrss << 10;  // ru_maxrss is in Kb.
 508 }
 509
 510 uptr GetRSS() {
 511   if (!common_flags()->can_use_proc_maps_statm)
 512     return GetRSSFromGetrusage();
 513   fd_t fd = OpenFile("/proc/self/statm", RdOnly);
 514   if (fd == kInvalidFd)
 515     return GetRSSFromGetrusage();
 516   char buf[64];
 517   uptr len = internal_read(fd, buf, sizeof(buf) - 1);
 518   internal_close(fd);
 519   if ((sptr)len <= 0)
 520     return 0;
 521   buf[len] = 0;
 522   // The format of the file is:
 523   // 1084 89 69 11 0 79 0
 524   // We need the second number which is RSS in pages.
 525   char *pos = buf;
 526   // Skip the first number.
 527   while (*pos >= '0' && *pos <= '9')
 528     pos++;
 529   // Skip whitespaces.
 530   while (!(*pos >= '0' && *pos <= '9') && *pos != 0)
 531     pos++;
 532   // Read the number.
 533   uptr rss = 0;
 534   while (*pos >= '0' && *pos <= '9')
 535     rss = rss * 10 + *pos++ - '0';
 536   return rss * GetPageSizeCached();
 537 }
 538
 539 // 64-bit Android targets don't provide the deprecated __android_log_write.
 540 // Starting with the L release, syslog() works and is preferable to
 541 // __android_log_write.
 542 #if SANITIZER_LINUX
 543
 544 #if SANITIZER_ANDROID
 545 static atomic_uint8_t android_log_initialized;
 546
 547 void AndroidLogInit() {
 548   openlog(GetProcessName(), 0, LOG_USER);
 549   atomic_store(&android_log_initialized, 1, memory_order_release);
 550 }
 551
 552 static bool ShouldLogAfterPrintf() {
 553   return atomic_load(&android_log_initialized, memory_order_acquire);
 554 }
 555 #else
 556 void AndroidLogInit() {}
 557
 558 static bool ShouldLogAfterPrintf() { return true; }
 559 #endif  // SANITIZER_ANDROID
 560
 561 void WriteOneLineToSyslog(const char *s) {
 562 #if SANITIZER_ANDROID &&__ANDROID_API__ < 21
 563   __android_log_write(ANDROID_LOG_INFO, NULL, s);
 564 #else
 565   syslog(LOG_INFO, "%s", s);
 566 #endif
 567 }
 568
 569 void LogMessageOnPrintf(const char *str) {
 570   if (common_flags()->log_to_syslog && ShouldLogAfterPrintf())
 571     WriteToSyslog(str);
 572 }
 573
 574 #if SANITIZER_ANDROID
 575 extern "C" __attribute__((weak)) void android_set_abort_message(const char *);
 576 void SetAbortMessage(const char *str) {
 577   if (&android_set_abort_message) android_set_abort_message(str);
 578 }
 579 #else
 580 void SetAbortMessage(const char *str) {}
 581 #endif
 582
 583 #endif // SANITIZER_LINUX
 584
 585 } // namespace __sanitizer
 586
 587 #endif // SANITIZER_FREEBSD || SANITIZER_LINUX