1 //===-- sanitizer_linux_libcdep.cc ----------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is shared between AddressSanitizer and ThreadSanitizer
11 // run-time libraries and implements linux-specific functions from
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_platform.h"
17 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
18 SANITIZER_OPENBSD || SANITIZER_SOLARIS
20 #include "sanitizer_allocator_internal.h"
21 #include "sanitizer_atomic.h"
22 #include "sanitizer_common.h"
23 #include "sanitizer_file.h"
24 #include "sanitizer_flags.h"
25 #include "sanitizer_freebsd.h"
26 #include "sanitizer_linux.h"
27 #include "sanitizer_placement_new.h"
28 #include "sanitizer_procmaps.h"
30 #include <dlfcn.h> // for dlsym()
34 #include <sys/resource.h>
38 #include <pthread_np.h>
39 #include <osreldate.h>
40 #include <sys/sysctl.h>
41 #define pthread_getattr_np pthread_attr_get_np
45 #include <pthread_np.h>
46 #include <sys/sysctl.h>
50 #include <sys/sysctl.h>
59 #include <android/api-level.h>
60 #if !defined(CPU_COUNT) && !defined(__aarch64__)
63 struct __sanitizer::linux_dirent {
66 unsigned short d_reclen;
72 #if !SANITIZER_ANDROID
77 namespace __sanitizer {
79 SANITIZER_WEAK_ATTRIBUTE int
80 real_sigaction(int signum, const void *act, void *oldact);
82 int internal_sigaction(int signum, const void *act, void *oldact) {
85 return real_sigaction(signum, act, oldact);
87 return sigaction(signum, (const struct sigaction *)act,
88 (struct sigaction *)oldact);
91 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
95 if (at_initialization) {
96 // This is the main thread. Libpthread may not be initialized yet.
98 CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
100 // Find the mapping that contains a stack variable.
101 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
102 MemoryMappedSegment segment;
104 while (proc_maps.Next(&segment)) {
105 if ((uptr)&rl < segment.end) break;
106 prev_end = segment.end;
108 CHECK((uptr)&rl >= segment.start && (uptr)&rl < segment.end);
110 // Get stacksize from rlimit, but clip it so that it does not overlap
111 // with other mappings.
112 uptr stacksize = rl.rlim_cur;
113 if (stacksize > segment.end - prev_end) stacksize = segment.end - prev_end;
114 // When running with unlimited stack size, we still want to set some limit.
115 // The unlimited stack size is caused by 'ulimit -s unlimited'.
116 // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
117 if (stacksize > kMaxThreadStackSize)
118 stacksize = kMaxThreadStackSize;
119 *stack_top = segment.end;
120 *stack_bottom = segment.end - stacksize;
124 void *stackaddr = nullptr;
125 #if SANITIZER_SOLARIS
127 CHECK_EQ(thr_stksegment(&ss), 0);
128 stacksize = ss.ss_size;
129 stackaddr = (char *)ss.ss_sp - stacksize;
130 #elif SANITIZER_OPENBSD
132 CHECK_EQ(pthread_stackseg_np(pthread_self(), &sattr), 0);
133 stackaddr = sattr.ss_sp;
134 stacksize = sattr.ss_size;
135 #else // !SANITIZER_SOLARIS
137 pthread_attr_init(&attr);
138 CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
139 my_pthread_attr_getstack(&attr, &stackaddr, &stacksize);
140 pthread_attr_destroy(&attr);
141 #endif // SANITIZER_SOLARIS
143 *stack_top = (uptr)stackaddr + stacksize;
144 *stack_bottom = (uptr)stackaddr;
148 bool SetEnv(const char *name, const char *value) {
149 void *f = dlsym(RTLD_NEXT, "setenv");
152 typedef int(*setenv_ft)(const char *name, const char *value, int overwrite);
154 CHECK_EQ(sizeof(setenv_f), sizeof(f));
155 internal_memcpy(&setenv_f, &f, sizeof(f));
156 return setenv_f(name, value, 1) == 0;
160 __attribute__((unused)) static bool GetLibcVersion(int *major, int *minor,
162 #ifdef _CS_GNU_LIBC_VERSION
164 uptr len = confstr(_CS_GNU_LIBC_VERSION, buf, sizeof(buf));
165 if (len >= sizeof(buf))
168 static const char kGLibC[] = "glibc ";
169 if (internal_strncmp(buf, kGLibC, sizeof(kGLibC) - 1) != 0)
171 const char *p = buf + sizeof(kGLibC) - 1;
172 *major = internal_simple_strtoll(p, &p, 10);
173 *minor = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
174 *patch = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
181 #if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && \
182 !SANITIZER_NETBSD && !SANITIZER_OPENBSD && !SANITIZER_SOLARIS
183 static uptr g_tls_size;
186 # ifndef __GLIBC_PREREQ
187 # define CHECK_GET_TLS_STATIC_INFO_VERSION 1
189 # define CHECK_GET_TLS_STATIC_INFO_VERSION (!__GLIBC_PREREQ(2, 27))
192 # define CHECK_GET_TLS_STATIC_INFO_VERSION 0
195 #if CHECK_GET_TLS_STATIC_INFO_VERSION
196 # define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall))
198 # define DL_INTERNAL_FUNCTION
202 struct GetTlsStaticInfoCall {
203 typedef void (*get_tls_func)(size_t*, size_t*);
205 struct GetTlsStaticInfoRegparmCall {
206 typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION;
209 template <typename T>
210 void CallGetTls(void* ptr, size_t* size, size_t* align) {
211 typename T::get_tls_func get_tls;
212 CHECK_EQ(sizeof(get_tls), sizeof(ptr));
213 internal_memcpy(&get_tls, &ptr, sizeof(ptr));
214 CHECK_NE(get_tls, 0);
215 get_tls(size, align);
218 bool CmpLibcVersion(int major, int minor, int patch) {
222 if (!GetLibcVersion(&ma, &mi, &pa))
238 // all current supported platforms have 16 bytes stack alignment
239 const size_t kStackAlign = 16;
240 void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
242 size_t tls_align = 0;
243 // On i?86, _dl_get_tls_static_info used to be internal_function, i.e.
244 // __attribute__((regparm(3), stdcall)) before glibc 2.27 and is normal
245 // function in 2.27 and later.
246 if (CHECK_GET_TLS_STATIC_INFO_VERSION && !CmpLibcVersion(2, 27, 0))
247 CallGetTls<GetTlsStaticInfoRegparmCall>(get_tls_static_info_ptr,
248 &tls_size, &tls_align);
250 CallGetTls<GetTlsStaticInfoCall>(get_tls_static_info_ptr,
251 &tls_size, &tls_align);
252 if (tls_align < kStackAlign)
253 tls_align = kStackAlign;
254 g_tls_size = RoundUpTo(tls_size, tls_align);
257 void InitTlsSize() { }
258 #endif // !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO &&
259 // !SANITIZER_NETBSD && !SANITIZER_SOLARIS
261 #if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) || \
262 defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__) || \
263 defined(__arm__)) && \
264 SANITIZER_LINUX && !SANITIZER_ANDROID
265 // sizeof(struct pthread) from glibc.
266 static atomic_uintptr_t thread_descriptor_size;
268 uptr ThreadDescriptorSize() {
269 uptr val = atomic_load_relaxed(&thread_descriptor_size);
272 #if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
276 if (GetLibcVersion(&major, &minor, &patch) && major == 2) {
277 /* sizeof(struct pthread) values from various glibc versions. */
279 val = 1728; // Assume only one particular version for x32.
280 // For ARM sizeof(struct pthread) changed in Glibc 2.23.
281 else if (SANITIZER_ARM)
282 val = minor <= 22 ? 1120 : 1216;
284 val = FIRST_32_SECOND_64(1104, 1696);
286 val = FIRST_32_SECOND_64(1120, 1728);
288 val = FIRST_32_SECOND_64(1136, 1728);
290 val = FIRST_32_SECOND_64(1136, 1712);
291 else if (minor == 10)
292 val = FIRST_32_SECOND_64(1168, 1776);
293 else if (minor == 11 || (minor == 12 && patch == 1))
294 val = FIRST_32_SECOND_64(1168, 2288);
295 else if (minor <= 14)
296 val = FIRST_32_SECOND_64(1168, 2304);
298 val = FIRST_32_SECOND_64(1216, 2304);
300 #elif defined(__mips__)
301 // TODO(sagarthakur): add more values as per different glibc versions.
302 val = FIRST_32_SECOND_64(1152, 1776);
303 #elif defined(__aarch64__)
304 // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22.
306 #elif defined(__powerpc64__)
307 val = 1776; // from glibc.ppc64le 2.20-8.fc21
308 #elif defined(__s390__)
309 val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
312 atomic_store_relaxed(&thread_descriptor_size, val);
316 // The offset at which pointer to self is located in the thread descriptor.
317 const uptr kThreadSelfOffset = FIRST_32_SECOND_64(8, 16);
319 uptr ThreadSelfOffset() {
320 return kThreadSelfOffset;
323 #if defined(__mips__) || defined(__powerpc64__)
324 // TlsPreTcbSize includes size of struct pthread_descr and size of tcb
325 // head structure. It lies before the static tls blocks.
326 static uptr TlsPreTcbSize() {
327 # if defined(__mips__)
328 const uptr kTcbHead = 16; // sizeof (tcbhead_t)
329 # elif defined(__powerpc64__)
330 const uptr kTcbHead = 88; // sizeof (tcbhead_t)
332 const uptr kTlsAlign = 16;
333 const uptr kTlsPreTcbSize =
334 RoundUpTo(ThreadDescriptorSize() + kTcbHead, kTlsAlign);
335 return kTlsPreTcbSize;
341 # if defined(__i386__)
342 asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
343 # elif defined(__x86_64__)
344 asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
345 # elif defined(__mips__)
346 // MIPS uses TLS variant I. The thread pointer (in hardware register $29)
347 // points to the end of the TCB + 0x7000. The pthread_descr structure is
348 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
349 // TCB and the size of pthread_descr.
350 const uptr kTlsTcbOffset = 0x7000;
352 asm volatile(".set push;\
355 .set pop" : "=r" (thread_pointer));
356 descr_addr = thread_pointer - kTlsTcbOffset - TlsPreTcbSize();
357 # elif defined(__aarch64__) || defined(__arm__)
358 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
359 ThreadDescriptorSize();
360 # elif defined(__s390__)
361 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer());
362 # elif defined(__powerpc64__)
363 // PPC64LE uses TLS variant I. The thread pointer (in GPR 13)
364 // points to the end of the TCB + 0x7000. The pthread_descr structure is
365 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
366 // TCB and the size of pthread_descr.
367 const uptr kTlsTcbOffset = 0x7000;
369 asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset));
370 descr_addr = thread_pointer - TlsPreTcbSize();
372 # error "unsupported CPU arch"
376 #endif // (x86_64 || i386 || MIPS) && SANITIZER_LINUX
378 #if SANITIZER_FREEBSD
379 static void **ThreadSelfSegbase() {
381 # if defined(__i386__)
382 // sysarch(I386_GET_GSBASE, segbase);
383 __asm __volatile("mov %%gs:0, %0" : "=r" (segbase));
384 # elif defined(__x86_64__)
385 // sysarch(AMD64_GET_FSBASE, segbase);
386 __asm __volatile("movq %%fs:0, %0" : "=r" (segbase));
388 # error "unsupported CPU arch"
394 return (uptr)ThreadSelfSegbase()[2];
396 #endif // SANITIZER_FREEBSD
399 static struct tls_tcb * ThreadSelfTlsTcb() {
400 struct tls_tcb * tcb;
401 # ifdef __HAVE___LWP_GETTCB_FAST
402 tcb = (struct tls_tcb *)__lwp_gettcb_fast();
403 # elif defined(__HAVE___LWP_GETPRIVATE_FAST)
404 tcb = (struct tls_tcb *)__lwp_getprivate_fast();
410 return (uptr)ThreadSelfTlsTcb()->tcb_pthread;
413 int GetSizeFromHdr(struct dl_phdr_info *info, size_t size, void *data) {
414 const Elf_Phdr *hdr = info->dlpi_phdr;
415 const Elf_Phdr *last_hdr = hdr + info->dlpi_phnum;
417 for (; hdr != last_hdr; ++hdr) {
418 if (hdr->p_type == PT_TLS && info->dlpi_tls_modid == 1) {
419 *(uptr*)data = hdr->p_memsz;
425 #endif // SANITIZER_NETBSD
428 static void GetTls(uptr *addr, uptr *size) {
429 #if SANITIZER_LINUX && !SANITIZER_ANDROID
430 # if defined(__x86_64__) || defined(__i386__) || defined(__s390__)
431 *addr = ThreadSelf();
432 *size = GetTlsSize();
434 *addr += ThreadDescriptorSize();
435 # elif defined(__mips__) || defined(__aarch64__) || defined(__powerpc64__) \
437 *addr = ThreadSelf();
438 *size = GetTlsSize();
443 #elif SANITIZER_FREEBSD
444 void** segbase = ThreadSelfSegbase();
449 // tls_size = round(tls_static_space, tcbalign);
451 // dtv[2] = segbase - tls_static_space;
452 void **dtv = (void**) segbase[1];
453 *addr = (uptr) dtv[2];
454 *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]);
456 #elif SANITIZER_NETBSD
457 struct tls_tcb * const tcb = ThreadSelfTlsTcb();
461 // Find size (p_memsz) of dlpi_tls_modid 1 (TLS block of the main program).
462 // ld.elf_so hardcodes the index 1.
463 dl_iterate_phdr(GetSizeFromHdr, size);
466 // The block has been found and tcb_dtv[1] contains the base address
467 *addr = (uptr)tcb->tcb_dtv[1];
470 #elif SANITIZER_OPENBSD
473 #elif SANITIZER_ANDROID
476 #elif SANITIZER_SOLARIS
488 #if SANITIZER_FREEBSD || SANITIZER_ANDROID || SANITIZER_NETBSD || \
489 SANITIZER_OPENBSD || SANITIZER_SOLARIS
491 GetTls(&addr, &size);
493 #elif defined(__mips__) || defined(__powerpc64__)
494 return RoundUpTo(g_tls_size + TlsPreTcbSize(), 16);
501 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
502 uptr *tls_addr, uptr *tls_size) {
504 // Stub implementation for Go.
505 *stk_addr = *stk_size = *tls_addr = *tls_size = 0;
507 GetTls(tls_addr, tls_size);
509 uptr stack_top, stack_bottom;
510 GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
511 *stk_addr = stack_bottom;
512 *stk_size = stack_top - stack_bottom;
515 // If stack and tls intersect, make them non-intersecting.
516 if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) {
517 CHECK_GT(*tls_addr + *tls_size, *stk_addr);
518 CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size);
519 *stk_size -= *tls_size;
520 *tls_addr = *stk_addr + *stk_size;
526 #if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
527 typedef ElfW(Phdr) Elf_Phdr;
528 #elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001 // v9.2
529 #define Elf_Phdr XElf32_Phdr
530 #define dl_phdr_info xdl_phdr_info
531 #define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b))
532 #endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
534 struct DlIteratePhdrData {
535 InternalMmapVectorNoCtor<LoadedModule> *modules;
539 static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
540 DlIteratePhdrData *data = (DlIteratePhdrData*)arg;
541 InternalScopedString module_name(kMaxPathLength);
544 // First module is the binary itself.
545 ReadBinaryNameCached(module_name.data(), module_name.size());
546 } else if (info->dlpi_name) {
547 module_name.append("%s", info->dlpi_name);
549 if (module_name[0] == '\0')
551 LoadedModule cur_module;
552 cur_module.set(module_name.data(), info->dlpi_addr);
553 for (int i = 0; i < (int)info->dlpi_phnum; i++) {
554 const Elf_Phdr *phdr = &info->dlpi_phdr[i];
555 if (phdr->p_type == PT_LOAD) {
556 uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
557 uptr cur_end = cur_beg + phdr->p_memsz;
558 bool executable = phdr->p_flags & PF_X;
559 bool writable = phdr->p_flags & PF_W;
560 cur_module.addAddressRange(cur_beg, cur_end, executable,
564 data->modules->push_back(cur_module);
568 #if SANITIZER_ANDROID && __ANDROID_API__ < 21
569 extern "C" __attribute__((weak)) int dl_iterate_phdr(
570 int (*)(struct dl_phdr_info *, size_t, void *), void *);
573 static bool requiresProcmaps() {
574 #if SANITIZER_ANDROID && __ANDROID_API__ <= 22
575 // Fall back to /proc/maps if dl_iterate_phdr is unavailable or broken.
576 // The runtime check allows the same library to work with
577 // both K and L (and future) Android releases.
578 return AndroidGetApiLevel() <= ANDROID_LOLLIPOP_MR1;
584 static void procmapsInit(InternalMmapVectorNoCtor<LoadedModule> *modules) {
585 MemoryMappingLayout memory_mapping(/*cache_enabled*/true);
586 memory_mapping.DumpListOfModules(modules);
589 void ListOfModules::init() {
591 if (requiresProcmaps()) {
592 procmapsInit(&modules_);
594 DlIteratePhdrData data = {&modules_, true};
595 dl_iterate_phdr(dl_iterate_phdr_cb, &data);
599 // When a custom loader is used, dl_iterate_phdr may not contain the full
600 // list of modules. Allow callers to fall back to using procmaps.
601 void ListOfModules::fallbackInit() {
602 if (!requiresProcmaps()) {
604 procmapsInit(&modules_);
610 // getrusage does not give us the current RSS, only the max RSS.
611 // Still, this is better than nothing if /proc/self/statm is not available
612 // for some reason, e.g. due to a sandbox.
613 static uptr GetRSSFromGetrusage() {
615 if (getrusage(RUSAGE_SELF, &usage)) // Failed, probably due to a sandbox.
617 return usage.ru_maxrss << 10; // ru_maxrss is in Kb.
621 if (!common_flags()->can_use_proc_maps_statm)
622 return GetRSSFromGetrusage();
623 fd_t fd = OpenFile("/proc/self/statm", RdOnly);
624 if (fd == kInvalidFd)
625 return GetRSSFromGetrusage();
627 uptr len = internal_read(fd, buf, sizeof(buf) - 1);
632 // The format of the file is:
633 // 1084 89 69 11 0 79 0
634 // We need the second number which is RSS in pages.
636 // Skip the first number.
637 while (*pos >= '0' && *pos <= '9')
640 while (!(*pos >= '0' && *pos <= '9') && *pos != 0)
644 while (*pos >= '0' && *pos <= '9')
645 rss = rss * 10 + *pos++ - '0';
646 return rss * GetPageSizeCached();
649 // sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used on most platforms as
650 // they allocate memory.
651 u32 GetNumberOfCPUs() {
652 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_OPENBSD
655 size_t len = sizeof(ncpu);
658 CHECK_EQ(sysctl(req, 2, &ncpu, &len, NULL, 0), 0);
660 #elif SANITIZER_ANDROID && !defined(CPU_COUNT) && !defined(__aarch64__)
661 // Fall back to /sys/devices/system/cpu on Android when cpu_set_t doesn't
662 // exist in sched.h. That is the case for toolchains generated with older
664 // This code doesn't work on AArch64 because internal_getdents makes use of
665 // the 64bit getdents syscall, but cpu_set_t seems to always exist on AArch64.
666 uptr fd = internal_open("/sys/devices/system/cpu", O_RDONLY | O_DIRECTORY);
667 if (internal_iserror(fd))
669 InternalMmapVector<u8> buffer(4096);
670 uptr bytes_read = buffer.size();
673 struct linux_dirent *entry = (struct linux_dirent *)&buffer[bytes_read];
675 if ((u8 *)entry >= &buffer[bytes_read]) {
676 bytes_read = internal_getdents(fd, (struct linux_dirent *)buffer.data(),
678 if (internal_iserror(bytes_read) || !bytes_read)
680 entry = (struct linux_dirent *)buffer.data();
682 d_type = (u8 *)entry + entry->d_reclen - 1;
683 if (d_type >= &buffer[bytes_read] ||
684 (u8 *)&entry->d_name[3] >= &buffer[bytes_read])
686 if (entry->d_ino != 0 && *d_type == DT_DIR) {
687 if (entry->d_name[0] == 'c' && entry->d_name[1] == 'p' &&
688 entry->d_name[2] == 'u' &&
689 entry->d_name[3] >= '0' && entry->d_name[3] <= '9')
692 entry = (struct linux_dirent *)(((u8 *)entry) + entry->d_reclen);
696 #elif SANITIZER_SOLARIS
697 return sysconf(_SC_NPROCESSORS_ONLN);
700 CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
701 return CPU_COUNT(&CPUs);
707 # if SANITIZER_ANDROID
708 static atomic_uint8_t android_log_initialized;
710 void AndroidLogInit() {
711 openlog(GetProcessName(), 0, LOG_USER);
712 atomic_store(&android_log_initialized, 1, memory_order_release);
715 static bool ShouldLogAfterPrintf() {
716 return atomic_load(&android_log_initialized, memory_order_acquire);
719 extern "C" SANITIZER_WEAK_ATTRIBUTE
720 int async_safe_write_log(int pri, const char* tag, const char* msg);
721 extern "C" SANITIZER_WEAK_ATTRIBUTE
722 int __android_log_write(int prio, const char* tag, const char* msg);
724 // ANDROID_LOG_INFO is 4, but can't be resolved at runtime.
725 #define SANITIZER_ANDROID_LOG_INFO 4
727 // async_safe_write_log is a new public version of __libc_write_log that is
728 // used behind syslog. It is preferable to syslog as it will not do any dynamic
729 // memory allocation or formatting.
730 // If the function is not available, syslog is preferred for L+ (it was broken
731 // pre-L) as __android_log_write triggers a racey behavior with the strncpy
732 // interceptor. Fallback to __android_log_write pre-L.
733 void WriteOneLineToSyslog(const char *s) {
734 if (&async_safe_write_log) {
735 async_safe_write_log(SANITIZER_ANDROID_LOG_INFO, GetProcessName(), s);
736 } else if (AndroidGetApiLevel() > ANDROID_KITKAT) {
737 syslog(LOG_INFO, "%s", s);
739 CHECK(&__android_log_write);
740 __android_log_write(SANITIZER_ANDROID_LOG_INFO, nullptr, s);
744 extern "C" SANITIZER_WEAK_ATTRIBUTE
745 void android_set_abort_message(const char *);
747 void SetAbortMessage(const char *str) {
748 if (&android_set_abort_message)
749 android_set_abort_message(str);
752 void AndroidLogInit() {}
754 static bool ShouldLogAfterPrintf() { return true; }
756 void WriteOneLineToSyslog(const char *s) { syslog(LOG_INFO, "%s", s); }
758 void SetAbortMessage(const char *str) {}
759 # endif // SANITIZER_ANDROID
761 void LogMessageOnPrintf(const char *str) {
762 if (common_flags()->log_to_syslog && ShouldLogAfterPrintf())
766 #endif // SANITIZER_LINUX
768 #if SANITIZER_LINUX && !SANITIZER_GO
769 // glibc crashes when using clock_gettime from a preinit_array function as the
770 // vDSO function pointers haven't been initialized yet. __progname is
771 // initialized after the vDSO function pointers, so if it exists, is not null
772 // and is not empty, we can use clock_gettime.
773 extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname;
774 INLINE bool CanUseVDSO() {
775 // Bionic is safe, it checks for the vDSO function pointers to be initialized.
776 if (SANITIZER_ANDROID)
778 if (&__progname && __progname && *__progname)
783 // MonotonicNanoTime is a timing function that can leverage the vDSO by calling
784 // clock_gettime. real_clock_gettime only exists if clock_gettime is
785 // intercepted, so define it weakly and use it if available.
786 extern "C" SANITIZER_WEAK_ATTRIBUTE
787 int real_clock_gettime(u32 clk_id, void *tp);
788 u64 MonotonicNanoTime() {
791 if (&real_clock_gettime)
792 real_clock_gettime(CLOCK_MONOTONIC, &ts);
794 clock_gettime(CLOCK_MONOTONIC, &ts);
796 internal_clock_gettime(CLOCK_MONOTONIC, &ts);
798 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
801 // Non-Linux & Go always use the syscall.
802 u64 MonotonicNanoTime() {
804 internal_clock_gettime(CLOCK_MONOTONIC, &ts);
805 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
807 #endif // SANITIZER_LINUX && !SANITIZER_GO
809 } // namespace __sanitizer