text: //===-- tsan_interceptors.cc ----------------------------------------------===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is distributed under the University of Illinois Open Source
  // License. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  //
  // This file is a part of ThreadSanitizer (TSan), a race detector.
  //
  // FIXME: move as many interceptors as possible into
  // sanitizer_common/sanitizer_common_interceptors.inc
  //===----------------------------------------------------------------------===//
  
  #include "sanitizer_common/sanitizer_atomic.h"
  #include "sanitizer_common/sanitizer_libc.h"
  #include "sanitizer_common/sanitizer_linux.h"
  #include "sanitizer_common/sanitizer_platform_limits_posix.h"
  #include "sanitizer_common/sanitizer_placement_new.h"
  #include "sanitizer_common/sanitizer_stacktrace.h"
  #include "interception/interception.h"
  #include "tsan_interface.h"
  #include "tsan_platform.h"
  #include "tsan_suppressions.h"
  #include "tsan_rtl.h"
  #include "tsan_mman.h"
  #include "tsan_fd.h"
  
  using namespace __tsan;  // NOLINT
  
  const int kSigCount = 65;
  
  struct my_siginfo_t {
    // The size is determined by looking at sizeof of real siginfo_t on linux.
    u64 opaque[128 / sizeof(u64)];
  };
  
  struct ucontext_t {
    // The size is determined by looking at sizeof of real ucontext_t on linux.
    u64 opaque[936 / sizeof(u64) + 1];
  };
  
  extern "C" int pthread_attr_init(void *attr);
  extern "C" int pthread_attr_destroy(void *attr);
  DECLARE_REAL(int, pthread_attr_getdetachstate, void *, void *)
  extern "C" int pthread_attr_setstacksize(void *attr, uptr stacksize);
  extern "C" int pthread_key_create(unsigned *key, void (*destructor)(void* v));
  extern "C" int pthread_setspecific(unsigned key, const void *v);
  DECLARE_REAL(int, pthread_mutexattr_gettype, void *, void *)
  extern "C" int pthread_yield();
  extern "C" int pthread_sigmask(int how, const __sanitizer_sigset_t *set,
                                 __sanitizer_sigset_t *oldset);
  // REAL(sigfillset) defined in common interceptors.
  DECLARE_REAL(int, sigfillset, __sanitizer_sigset_t *set)
  DECLARE_REAL(int, fflush, __sanitizer_FILE *fp)
  extern "C" void *pthread_self();
  extern "C" void _exit(int status);
  extern "C" int *__errno_location();
  extern "C" int fileno_unlocked(void *stream);
  extern "C" void *__libc_malloc(uptr size);
  extern "C" void *__libc_calloc(uptr size, uptr n);
  extern "C" void *__libc_realloc(void *ptr, uptr size);
  extern "C" void __libc_free(void *ptr);
  extern "C" int mallopt(int param, int value);
  extern __sanitizer_FILE *stdout, *stderr;
  const int PTHREAD_MUTEX_RECURSIVE = 1;
  const int PTHREAD_MUTEX_RECURSIVE_NP = 1;
  const int EINVAL = 22;
  const int EBUSY = 16;
  const int EOWNERDEAD = 130;
  const int EPOLL_CTL_ADD = 1;
  const int SIGILL = 4;
  const int SIGABRT = 6;
  const int SIGFPE = 8;
  const int SIGSEGV = 11;
  const int SIGPIPE = 13;
  const int SIGTERM = 15;
  const int SIGBUS = 7;
  const int SIGSYS = 31;
  void *const MAP_FAILED = (void*)-1;
  const int PTHREAD_BARRIER_SERIAL_THREAD = -1;
  const int MAP_FIXED = 0x10;
  typedef long long_t;  // NOLINT
  
  // From /usr/include/unistd.h
  # define F_ULOCK 0      /* Unlock a previously locked region.  */
  # define F_LOCK  1      /* Lock a region for exclusive use.  */
  # define F_TLOCK 2      /* Test and lock a region for exclusive use.  */
  # define F_TEST  3      /* Test a region for other processes locks.  */
  
  typedef void (*sighandler_t)(int sig);
  
  #define errno (*__errno_location())
  
  struct sigaction_t {
    union {
      sighandler_t sa_handler;
      void (*sa_sigaction)(int sig, my_siginfo_t *siginfo, void *uctx);
    };
    __sanitizer_sigset_t sa_mask;
    int sa_flags;
    void (*sa_restorer)();
  };
  
  const sighandler_t SIG_DFL = (sighandler_t)0;
  const sighandler_t SIG_IGN = (sighandler_t)1;
  const sighandler_t SIG_ERR = (sighandler_t)-1;
  const int SA_SIGINFO = 4;
  const int SIG_SETMASK = 2;
  
  namespace std {
  struct nothrow_t {};
  }  // namespace std
  
  static sigaction_t sigactions[kSigCount];
  
  namespace __tsan {
  struct SignalDesc {
    bool armed;
    bool sigaction;
    my_siginfo_t siginfo;
    ucontext_t ctx;
  };
  
  struct SignalContext {
    int in_blocking_func;
    int int_signal_send;
    int pending_signal_count;
    SignalDesc pending_signals[kSigCount];
  };
  
  // The object is 64-byte aligned, because we want hot data to be located in
  // a single cache line if possible (it's accessed in every interceptor).
  static ALIGNED(64) char libignore_placeholder[sizeof(LibIgnore)];
  static LibIgnore *libignore() {
    return reinterpret_cast<LibIgnore*>(&libignore_placeholder[0]);
  }
  
  void InitializeLibIgnore() {
    libignore()->Init(*SuppressionContext::Get());
    libignore()->OnLibraryLoaded(0);
  }
  
  }  // namespace __tsan
  
  static SignalContext *SigCtx(ThreadState *thr) {
    SignalContext *ctx = (SignalContext*)thr->signal_ctx;
    if (ctx == 0 && thr->is_alive) {
      ctx = (SignalContext*)MmapOrDie(sizeof(*ctx), "SignalContext");
      MemoryResetRange(thr, (uptr)&SigCtx, (uptr)ctx, sizeof(*ctx));
      thr->signal_ctx = ctx;
    }
    return ctx;
  }
  
  static unsigned g_thread_finalize_key;
  
  class ScopedInterceptor {
   public:
    ScopedInterceptor(ThreadState *thr, const char *fname, uptr pc);
    ~ScopedInterceptor();
   private:
    ThreadState *const thr_;
    const uptr pc_;
    bool in_ignored_lib_;
  };
  
  ScopedInterceptor::ScopedInterceptor(ThreadState *thr, const char *fname,
                                       uptr pc)
      : thr_(thr)
      , pc_(pc)
      , in_ignored_lib_(false) {
    if (!thr_->ignore_interceptors) {
      Initialize(thr);
      FuncEntry(thr, pc);
    }
    DPrintf("#%d: intercept %s()\n", thr_->tid, fname);
    if (!thr_->in_ignored_lib && libignore()->IsIgnored(pc)) {
      in_ignored_lib_ = true;
      thr_->in_ignored_lib = true;
      ThreadIgnoreBegin(thr_, pc_);
    }
  }
  
  ScopedInterceptor::~ScopedInterceptor() {
    if (in_ignored_lib_) {
      thr_->in_ignored_lib = false;
      ThreadIgnoreEnd(thr_, pc_);
    }
    if (!thr_->ignore_interceptors) {
      ProcessPendingSignals(thr_);
      FuncExit(thr_);
      CheckNoLocks(thr_);
    }
  }
  
  #define SCOPED_INTERCEPTOR_RAW(func, ...) \
      ThreadState *thr = cur_thread(); \
      const uptr caller_pc = GET_CALLER_PC(); \
      ScopedInterceptor si(thr, #func, caller_pc); \
      const uptr pc = __sanitizer::StackTrace::GetCurrentPc(); \
      (void)pc; \
  /**/
  
  #define SCOPED_TSAN_INTERCEPTOR(func, ...) \
      SCOPED_INTERCEPTOR_RAW(func, __VA_ARGS__); \
      if (REAL(func) == 0) { \
        Report("FATAL: ThreadSanitizer: failed to intercept %s\n", #func); \
        Die(); \
      }                                                    \
      if (thr->ignore_interceptors || thr->in_ignored_lib) \
        return REAL(func)(__VA_ARGS__); \
  /**/
  
  #define TSAN_INTERCEPTOR(ret, func, ...) INTERCEPTOR(ret, func, __VA_ARGS__)
  #define TSAN_INTERCEPT(func) INTERCEPT_FUNCTION(func)
  #define TSAN_INTERCEPT_VER(func, ver) INTERCEPT_FUNCTION_VER(func, ver)
  
  #define BLOCK_REAL(name) (BlockingCall(thr), REAL(name))
  
  struct BlockingCall {
    explicit BlockingCall(ThreadState *thr)
        : ctx(SigCtx(thr)) {
      ctx->in_blocking_func++;
    }
  
    ~BlockingCall() {
      ctx->in_blocking_func--;
    }
  
    SignalContext *ctx;
  
    // When we are in a "blocking call", we process signals asynchronously
    // (right when they arrive). In this context we do not expect to be
    // executing any user/runtime code. The known interceptor sequence when
    // this is not true is: pthread_join -> munmap(stack). It's fine
    // to ignore munmap in this case -- we handle stack shadow separately.
    ScopedIgnoreInterceptors ignore_interceptors;
  };
  
  TSAN_INTERCEPTOR(unsigned, sleep, unsigned sec) {
    SCOPED_TSAN_INTERCEPTOR(sleep, sec);
    unsigned res = BLOCK_REAL(sleep)(sec);
    AfterSleep(thr, pc);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, usleep, long_t usec) {
    SCOPED_TSAN_INTERCEPTOR(usleep, usec);
    int res = BLOCK_REAL(usleep)(usec);
    AfterSleep(thr, pc);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, nanosleep, void *req, void *rem) {
    SCOPED_TSAN_INTERCEPTOR(nanosleep, req, rem);
    int res = BLOCK_REAL(nanosleep)(req, rem);
    AfterSleep(thr, pc);
    return res;
  }
  
  class AtExitContext {
   public:
    AtExitContext()
      : mtx_(MutexTypeAtExit, StatMtxAtExit)
      , pos_() {
    }
  
    typedef void(*atexit_t)();
  
    int atexit(ThreadState *thr, uptr pc, bool is_on_exit,
               atexit_t f, void *arg) {
      Lock l(&mtx_);
      if (pos_ == kMaxAtExit)
        return 1;
      Release(thr, pc, (uptr)this);
      stack_[pos_] = f;
      args_[pos_] = arg;
      is_on_exits_[pos_] = is_on_exit;
      pos_++;
      return 0;
    }
  
    void exit(ThreadState *thr, uptr pc) {
      for (;;) {
        atexit_t f = 0;
        void *arg = 0;
        bool is_on_exit = false;
        {
          Lock l(&mtx_);
          if (pos_) {
            pos_--;
            f = stack_[pos_];
            arg = args_[pos_];
            is_on_exit = is_on_exits_[pos_];
            Acquire(thr, pc, (uptr)this);
          }
        }
        if (f == 0)
          break;
        DPrintf("#%d: executing atexit func %p\n", thr->tid, f);
        if (is_on_exit)
          ((void(*)(int status, void *arg))f)(0, arg);
        else
          ((void(*)(void *arg, void *dso))f)(arg, 0);
      }
    }
  
   private:
    static const int kMaxAtExit = 128;
    Mutex mtx_;
    atexit_t stack_[kMaxAtExit];
    void *args_[kMaxAtExit];
    bool is_on_exits_[kMaxAtExit];
    int pos_;
  };
  
  static AtExitContext *atexit_ctx;
  
  TSAN_INTERCEPTOR(int, atexit, void (*f)()) {
    if (cur_thread()->in_symbolizer)
      return 0;
    // We want to setup the atexit callback even if we are in ignored lib
    // or after fork.
    SCOPED_INTERCEPTOR_RAW(atexit, f);
    return atexit_ctx->atexit(thr, pc, false, (void(*)())f, 0);
  }
  
  TSAN_INTERCEPTOR(int, on_exit, void(*f)(int, void*), void *arg) {
    if (cur_thread()->in_symbolizer)
      return 0;
    SCOPED_TSAN_INTERCEPTOR(on_exit, f, arg);
    return atexit_ctx->atexit(thr, pc, true, (void(*)())f, arg);
  }
  
  TSAN_INTERCEPTOR(int, __cxa_atexit, void (*f)(void *a), void *arg, void *dso) {
    if (cur_thread()->in_symbolizer)
      return 0;
    SCOPED_TSAN_INTERCEPTOR(__cxa_atexit, f, arg, dso);
    if (dso) {
      // Memory allocation in __cxa_atexit will race with free during exit,
      // because we do not see synchronization around atexit callback list.
      ThreadIgnoreBegin(thr, pc);
      int res = REAL(__cxa_atexit)(f, arg, dso);
      ThreadIgnoreEnd(thr, pc);
      return res;
    }
    return atexit_ctx->atexit(thr, pc, false, (void(*)())f, arg);
  }
  
  // Cleanup old bufs.
  static void JmpBufGarbageCollect(ThreadState *thr, uptr sp) {
    for (uptr i = 0; i < thr->jmp_bufs.Size(); i++) {
      JmpBuf *buf = &thr->jmp_bufs[i];
      if (buf->sp <= sp) {
        uptr sz = thr->jmp_bufs.Size();
        thr->jmp_bufs[i] = thr->jmp_bufs[sz - 1];
        thr->jmp_bufs.PopBack();
        i--;
      }
    }
  }
  
  static void SetJmp(ThreadState *thr, uptr sp, uptr mangled_sp) {
    if (thr->shadow_stack_pos == 0)  // called from libc guts during bootstrap
      return;
    // Cleanup old bufs.
    JmpBufGarbageCollect(thr, sp);
    // Remember the buf.
    JmpBuf *buf = thr->jmp_bufs.PushBack();
    buf->sp = sp;
    buf->mangled_sp = mangled_sp;
    buf->shadow_stack_pos = thr->shadow_stack_pos;
  }
  
  static void LongJmp(ThreadState *thr, uptr *env) {
    uptr mangled_sp = env[6];
    // Find the saved buf by mangled_sp.
    for (uptr i = 0; i < thr->jmp_bufs.Size(); i++) {
      JmpBuf *buf = &thr->jmp_bufs[i];
      if (buf->mangled_sp == mangled_sp) {
        CHECK_GE(thr->shadow_stack_pos, buf->shadow_stack_pos);
        // Unwind the stack.
        while (thr->shadow_stack_pos > buf->shadow_stack_pos)
          FuncExit(thr);
        JmpBufGarbageCollect(thr, buf->sp - 1);  // do not collect buf->sp
        return;
      }
    }
    Printf("ThreadSanitizer: can't find longjmp buf\n");
    CHECK(0);
  }
  
  // FIXME: put everything below into a common extern "C" block?
  extern "C" void __tsan_setjmp(uptr sp, uptr mangled_sp) {
    SetJmp(cur_thread(), sp, mangled_sp);
  }
  
  // Not called.  Merely to satisfy TSAN_INTERCEPT().
  extern "C" SANITIZER_INTERFACE_ATTRIBUTE
  int __interceptor_setjmp(void *env);
  extern "C" int __interceptor_setjmp(void *env) {
    CHECK(0);
    return 0;
  }
  
  // FIXME: any reason to have a separate declaration?
  extern "C" SANITIZER_INTERFACE_ATTRIBUTE
  int __interceptor__setjmp(void *env);
  extern "C" int __interceptor__setjmp(void *env) {
    CHECK(0);
    return 0;
  }
  
  extern "C" SANITIZER_INTERFACE_ATTRIBUTE
  int __interceptor_sigsetjmp(void *env);
  extern "C" int __interceptor_sigsetjmp(void *env) {
    CHECK(0);
    return 0;
  }
  
  extern "C" SANITIZER_INTERFACE_ATTRIBUTE
  int __interceptor___sigsetjmp(void *env);
  extern "C" int __interceptor___sigsetjmp(void *env) {
    CHECK(0);
    return 0;
  }
  
  extern "C" int setjmp(void *env);
  extern "C" int _setjmp(void *env);
  extern "C" int sigsetjmp(void *env);
  extern "C" int __sigsetjmp(void *env);
  DEFINE_REAL(int, setjmp, void *env)
  DEFINE_REAL(int, _setjmp, void *env)
  DEFINE_REAL(int, sigsetjmp, void *env)
  DEFINE_REAL(int, __sigsetjmp, void *env)
  
  TSAN_INTERCEPTOR(void, longjmp, uptr *env, int val) {
    {
      SCOPED_TSAN_INTERCEPTOR(longjmp, env, val);
    }
    LongJmp(cur_thread(), env);
    REAL(longjmp)(env, val);
  }
  
  TSAN_INTERCEPTOR(void, siglongjmp, uptr *env, int val) {
    {
      SCOPED_TSAN_INTERCEPTOR(siglongjmp, env, val);
    }
    LongJmp(cur_thread(), env);
    REAL(siglongjmp)(env, val);
  }
  
  TSAN_INTERCEPTOR(void*, malloc, uptr size) {
    if (cur_thread()->in_symbolizer)
      return __libc_malloc(size);
    void *p = 0;
    {
      SCOPED_INTERCEPTOR_RAW(malloc, size);
      p = user_alloc(thr, pc, size);
    }
    invoke_malloc_hook(p, size);
    return p;
  }
  
  TSAN_INTERCEPTOR(void*, __libc_memalign, uptr align, uptr sz) {
    SCOPED_TSAN_INTERCEPTOR(__libc_memalign, align, sz);
    return user_alloc(thr, pc, sz, align);
  }
  
  TSAN_INTERCEPTOR(void*, calloc, uptr size, uptr n) {
    if (cur_thread()->in_symbolizer)
      return __libc_calloc(size, n);
    if (__sanitizer::CallocShouldReturnNullDueToOverflow(size, n))
      return AllocatorReturnNull();
    void *p = 0;
    {
      SCOPED_INTERCEPTOR_RAW(calloc, size, n);
      p = user_alloc(thr, pc, n * size);
      if (p)
        internal_memset(p, 0, n * size);
    }
    invoke_malloc_hook(p, n * size);
    return p;
  }
  
  TSAN_INTERCEPTOR(void*, realloc, void *p, uptr size) {
    if (cur_thread()->in_symbolizer)
      return __libc_realloc(p, size);
    if (p)
      invoke_free_hook(p);
    {
      SCOPED_INTERCEPTOR_RAW(realloc, p, size);
      p = user_realloc(thr, pc, p, size);
    }
    invoke_malloc_hook(p, size);
    return p;
  }
  
  TSAN_INTERCEPTOR(void, free, void *p) {
    if (p == 0)
      return;
    if (cur_thread()->in_symbolizer)
      return __libc_free(p);
    invoke_free_hook(p);
    SCOPED_INTERCEPTOR_RAW(free, p);
    user_free(thr, pc, p);
  }
  
  TSAN_INTERCEPTOR(void, cfree, void *p) {
    if (p == 0)
      return;
    if (cur_thread()->in_symbolizer)
      return __libc_free(p);
    invoke_free_hook(p);
    SCOPED_INTERCEPTOR_RAW(cfree, p);
    user_free(thr, pc, p);
  }
  
  TSAN_INTERCEPTOR(uptr, malloc_usable_size, void *p) {
    SCOPED_INTERCEPTOR_RAW(malloc_usable_size, p);
    return user_alloc_usable_size(p);
  }
  
  #define OPERATOR_NEW_BODY(mangled_name) \
    if (cur_thread()->in_symbolizer) \
      return __libc_malloc(size); \
    void *p = 0; \
    {  \
      SCOPED_INTERCEPTOR_RAW(mangled_name, size); \
      p = user_alloc(thr, pc, size); \
    }  \
    invoke_malloc_hook(p, size);  \
    return p;
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void *operator new(__sanitizer::uptr size);
  void *operator new(__sanitizer::uptr size) {
    OPERATOR_NEW_BODY(_Znwm);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void *operator new[](__sanitizer::uptr size);
  void *operator new[](__sanitizer::uptr size) {
    OPERATOR_NEW_BODY(_Znam);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void *operator new(__sanitizer::uptr size, std::nothrow_t const&);
  void *operator new(__sanitizer::uptr size, std::nothrow_t const&) {
    OPERATOR_NEW_BODY(_ZnwmRKSt9nothrow_t);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void *operator new[](__sanitizer::uptr size, std::nothrow_t const&);
  void *operator new[](__sanitizer::uptr size, std::nothrow_t const&) {
    OPERATOR_NEW_BODY(_ZnamRKSt9nothrow_t);
  }
  
  #define OPERATOR_DELETE_BODY(mangled_name) \
    if (ptr == 0) return;  \
    if (cur_thread()->in_symbolizer) \
      return __libc_free(ptr); \
    invoke_free_hook(ptr);  \
    SCOPED_INTERCEPTOR_RAW(mangled_name, ptr);  \
    user_free(thr, pc, ptr);
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void operator delete(void *ptr) throw();
  void operator delete(void *ptr) throw() {
    OPERATOR_DELETE_BODY(_ZdlPv);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void operator delete[](void *ptr) throw();
  void operator delete[](void *ptr) throw() {
    OPERATOR_DELETE_BODY(_ZdaPv);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void operator delete(void *ptr, std::nothrow_t const&);
  void operator delete(void *ptr, std::nothrow_t const&) {
    OPERATOR_DELETE_BODY(_ZdlPvRKSt9nothrow_t);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void operator delete[](void *ptr, std::nothrow_t const&);
  void operator delete[](void *ptr, std::nothrow_t const&) {
    OPERATOR_DELETE_BODY(_ZdaPvRKSt9nothrow_t);
  }
  
  TSAN_INTERCEPTOR(uptr, strlen, const char *s) {
    SCOPED_TSAN_INTERCEPTOR(strlen, s);
    uptr len = internal_strlen(s);
    MemoryAccessRange(thr, pc, (uptr)s, len + 1, false);
    return len;
  }
  
  TSAN_INTERCEPTOR(void*, memset, void *dst, int v, uptr size) {
    SCOPED_TSAN_INTERCEPTOR(memset, dst, v, size);
    MemoryAccessRange(thr, pc, (uptr)dst, size, true);
    return internal_memset(dst, v, size);
  }
  
  TSAN_INTERCEPTOR(void*, memcpy, void *dst, const void *src, uptr size) {
    SCOPED_TSAN_INTERCEPTOR(memcpy, dst, src, size);
    MemoryAccessRange(thr, pc, (uptr)dst, size, true);
    MemoryAccessRange(thr, pc, (uptr)src, size, false);
    return internal_memcpy(dst, src, size);
  }
  
  TSAN_INTERCEPTOR(int, memcmp, const void *s1, const void *s2, uptr n) {
    SCOPED_TSAN_INTERCEPTOR(memcmp, s1, s2, n);
    int res = 0;
    uptr len = 0;
    for (; len < n; len++) {
      if ((res = ((unsigned char*)s1)[len] - ((unsigned char*)s2)[len]))
        break;
    }
    MemoryAccessRange(thr, pc, (uptr)s1, len < n ? len + 1 : n, false);
    MemoryAccessRange(thr, pc, (uptr)s2, len < n ? len + 1 : n, false);
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, memmove, void *dst, void *src, uptr n) {
    SCOPED_TSAN_INTERCEPTOR(memmove, dst, src, n);
    MemoryAccessRange(thr, pc, (uptr)dst, n, true);
    MemoryAccessRange(thr, pc, (uptr)src, n, false);
    return REAL(memmove)(dst, src, n);
  }
  
  TSAN_INTERCEPTOR(char*, strchr, char *s, int c) {
    SCOPED_TSAN_INTERCEPTOR(strchr, s, c);
    char *res = REAL(strchr)(s, c);
    uptr len = res ? (char*)res - (char*)s + 1 : internal_strlen(s) + 1;
    MemoryAccessRange(thr, pc, (uptr)s, len, false);
    return res;
  }
  
  TSAN_INTERCEPTOR(char*, strchrnul, char *s, int c) {
    SCOPED_TSAN_INTERCEPTOR(strchrnul, s, c);
    char *res = REAL(strchrnul)(s, c);
    uptr len = (char*)res - (char*)s + 1;
    MemoryAccessRange(thr, pc, (uptr)s, len, false);
    return res;
  }
  
  TSAN_INTERCEPTOR(char*, strrchr, char *s, int c) {
    SCOPED_TSAN_INTERCEPTOR(strrchr, s, c);
    MemoryAccessRange(thr, pc, (uptr)s, internal_strlen(s) + 1, false);
    return REAL(strrchr)(s, c);
  }
  
  TSAN_INTERCEPTOR(char*, strcpy, char *dst, const char *src) {  // NOLINT
    SCOPED_TSAN_INTERCEPTOR(strcpy, dst, src);  // NOLINT
    uptr srclen = internal_strlen(src);
    MemoryAccessRange(thr, pc, (uptr)dst, srclen + 1, true);
    MemoryAccessRange(thr, pc, (uptr)src, srclen + 1, false);
    return REAL(strcpy)(dst, src);  // NOLINT
  }
  
  TSAN_INTERCEPTOR(char*, strncpy, char *dst, char *src, uptr n) {
    SCOPED_TSAN_INTERCEPTOR(strncpy, dst, src, n);
    uptr srclen = internal_strnlen(src, n);
    MemoryAccessRange(thr, pc, (uptr)dst, n, true);
    MemoryAccessRange(thr, pc, (uptr)src, min(srclen + 1, n), false);
    return REAL(strncpy)(dst, src, n);
  }
  
  TSAN_INTERCEPTOR(const char*, strstr, const char *s1, const char *s2) {
    SCOPED_TSAN_INTERCEPTOR(strstr, s1, s2);
    const char *res = REAL(strstr)(s1, s2);
    uptr len1 = internal_strlen(s1);
    uptr len2 = internal_strlen(s2);
    MemoryAccessRange(thr, pc, (uptr)s1, len1 + 1, false);
    MemoryAccessRange(thr, pc, (uptr)s2, len2 + 1, false);
    return res;
  }
  
  TSAN_INTERCEPTOR(char*, strdup, const char *str) {
    SCOPED_TSAN_INTERCEPTOR(strdup, str);
    // strdup will call malloc, so no instrumentation is required here.
    return REAL(strdup)(str);
  }
  
  static bool fix_mmap_addr(void **addr, long_t sz, int flags) {
    if (*addr) {
      if (!IsAppMem((uptr)*addr) || !IsAppMem((uptr)*addr + sz - 1)) {
        if (flags & MAP_FIXED) {
          errno = EINVAL;
          return false;
        } else {
          *addr = 0;
        }
      }
    }
    return true;
  }
  
  TSAN_INTERCEPTOR(void*, mmap, void *addr, long_t sz, int prot,
                           int flags, int fd, unsigned off) {
    SCOPED_TSAN_INTERCEPTOR(mmap, addr, sz, prot, flags, fd, off);
    if (!fix_mmap_addr(&addr, sz, flags))
      return MAP_FAILED;
    void *res = REAL(mmap)(addr, sz, prot, flags, fd, off);
    if (res != MAP_FAILED) {
      if (fd > 0)
        FdAccess(thr, pc, fd);
      MemoryRangeImitateWrite(thr, pc, (uptr)res, sz);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, mmap64, void *addr, long_t sz, int prot,
                             int flags, int fd, u64 off) {
    SCOPED_TSAN_INTERCEPTOR(mmap64, addr, sz, prot, flags, fd, off);
    if (!fix_mmap_addr(&addr, sz, flags))
      return MAP_FAILED;
    void *res = REAL(mmap64)(addr, sz, prot, flags, fd, off);
    if (res != MAP_FAILED) {
      if (fd > 0)
        FdAccess(thr, pc, fd);
      MemoryRangeImitateWrite(thr, pc, (uptr)res, sz);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, munmap, void *addr, long_t sz) {
    SCOPED_TSAN_INTERCEPTOR(munmap, addr, sz);
    DontNeedShadowFor((uptr)addr, sz);
    int res = REAL(munmap)(addr, sz);
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, memalign, uptr align, uptr sz) {
    SCOPED_INTERCEPTOR_RAW(memalign, align, sz);
    return user_alloc(thr, pc, sz, align);
  }
  
  TSAN_INTERCEPTOR(void*, aligned_alloc, uptr align, uptr sz) {
    SCOPED_INTERCEPTOR_RAW(memalign, align, sz);
    return user_alloc(thr, pc, sz, align);
  }
  
  TSAN_INTERCEPTOR(void*, valloc, uptr sz) {
    SCOPED_INTERCEPTOR_RAW(valloc, sz);
    return user_alloc(thr, pc, sz, GetPageSizeCached());
  }
  
  TSAN_INTERCEPTOR(void*, pvalloc, uptr sz) {
    SCOPED_INTERCEPTOR_RAW(pvalloc, sz);
    sz = RoundUp(sz, GetPageSizeCached());
    return user_alloc(thr, pc, sz, GetPageSizeCached());
  }
  
  TSAN_INTERCEPTOR(int, posix_memalign, void **memptr, uptr align, uptr sz) {
    SCOPED_INTERCEPTOR_RAW(posix_memalign, memptr, align, sz);
    *memptr = user_alloc(thr, pc, sz, align);
    return 0;
  }
  
  // Used in thread-safe function static initialization.
  extern "C" int INTERFACE_ATTRIBUTE __cxa_guard_acquire(atomic_uint32_t *g) {
    SCOPED_INTERCEPTOR_RAW(__cxa_guard_acquire, g);
    for (;;) {
      u32 cmp = atomic_load(g, memory_order_acquire);
      if (cmp == 0) {
        if (atomic_compare_exchange_strong(g, &cmp, 1<<16, memory_order_relaxed))
          return 1;
      } else if (cmp == 1) {
        Acquire(thr, pc, (uptr)g);
        return 0;
      } else {
        internal_sched_yield();
      }
    }
  }
  
  extern "C" void INTERFACE_ATTRIBUTE __cxa_guard_release(atomic_uint32_t *g) {
    SCOPED_INTERCEPTOR_RAW(__cxa_guard_release, g);
    Release(thr, pc, (uptr)g);
    atomic_store(g, 1, memory_order_release);
  }
  
  extern "C" void INTERFACE_ATTRIBUTE __cxa_guard_abort(atomic_uint32_t *g) {
    SCOPED_INTERCEPTOR_RAW(__cxa_guard_abort, g);
    atomic_store(g, 0, memory_order_relaxed);
  }
  
  static void thread_finalize(void *v) {
    uptr iter = (uptr)v;
    if (iter > 1) {
      if (pthread_setspecific(g_thread_finalize_key, (void*)(iter - 1))) {
        Printf("ThreadSanitizer: failed to set thread key\n");
        Die();
      }
      return;
    }
    {
      ThreadState *thr = cur_thread();
      ThreadFinish(thr);
      SignalContext *sctx = thr->signal_ctx;
      if (sctx) {
        thr->signal_ctx = 0;
        UnmapOrDie(sctx, sizeof(*sctx));
      }
    }
  }
  
  
  struct ThreadParam {
    void* (*callback)(void *arg);
    void *param;
    atomic_uintptr_t tid;
  };
  
  extern "C" void *__tsan_thread_start_func(void *arg) {
    ThreadParam *p = (ThreadParam*)arg;
    void* (*callback)(void *arg) = p->callback;
    void *param = p->param;
    int tid = 0;
    {
      ThreadState *thr = cur_thread();
      // Thread-local state is not initialized yet.
      ScopedIgnoreInterceptors ignore;
      if (pthread_setspecific(g_thread_finalize_key,
                              (void *)kPthreadDestructorIterations)) {
        Printf("ThreadSanitizer: failed to set thread key\n");
        Die();
      }
      while ((tid = atomic_load(&p->tid, memory_order_acquire)) == 0)
        pthread_yield();
      atomic_store(&p->tid, 0, memory_order_release);
      ThreadStart(thr, tid, GetTid());
    }
    void *res = callback(param);
    // Prevent the callback from being tail called,
    // it mixes up stack traces.
    volatile int foo = 42;
    foo++;
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_create,
      void *th, void *attr, void *(*callback)(void*), void * param) {
    SCOPED_INTERCEPTOR_RAW(pthread_create, th, attr, callback, param);
    if (ctx->after_multithreaded_fork) {
      if (flags()->die_after_fork) {
        Report("ThreadSanitizer: starting new threads after multi-threaded "
            "fork is not supported. Dying (set die_after_fork=0 to override)\n");
        Die();
      } else {
        VPrintf(1, "ThreadSanitizer: starting new threads after multi-threaded "
            "fork is not supported (pid %d). Continuing because of "
            "die_after_fork=0, but you are on your own\n", internal_getpid());
      }
    }
    __sanitizer_pthread_attr_t myattr;
    if (attr == 0) {
      pthread_attr_init(&myattr);
      attr = &myattr;
    }
    int detached = 0;
    REAL(pthread_attr_getdetachstate)(attr, &detached);
    AdjustStackSize(attr);
  
    ThreadParam p;
    p.callback = callback;
    p.param = param;
    atomic_store(&p.tid, 0, memory_order_relaxed);
    int res = -1;
    {
      // Otherwise we see false positives in pthread stack manipulation.
      ScopedIgnoreInterceptors ignore;
      ThreadIgnoreBegin(thr, pc);
      res = REAL(pthread_create)(th, attr, __tsan_thread_start_func, &p);
      ThreadIgnoreEnd(thr, pc);
    }
    if (res == 0) {
      int tid = ThreadCreate(thr, pc, *(uptr*)th, detached);
      CHECK_NE(tid, 0);
      atomic_store(&p.tid, tid, memory_order_release);
      while (atomic_load(&p.tid, memory_order_acquire) != 0)
        pthread_yield();
    }
    if (attr == &myattr)
      pthread_attr_destroy(&myattr);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_join, void *th, void **ret) {
    SCOPED_INTERCEPTOR_RAW(pthread_join, th, ret);
    int tid = ThreadTid(thr, pc, (uptr)th);
    ThreadIgnoreBegin(thr, pc);
    int res = BLOCK_REAL(pthread_join)(th, ret);
    ThreadIgnoreEnd(thr, pc);
    if (res == 0) {
      ThreadJoin(thr, pc, tid);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_detach, void *th) {
    SCOPED_TSAN_INTERCEPTOR(pthread_detach, th);
    int tid = ThreadTid(thr, pc, (uptr)th);
    int res = REAL(pthread_detach)(th);
    if (res == 0) {
      ThreadDetach(thr, pc, tid);
    }
    return res;
  }
  
  // Problem:
  // NPTL implementation of pthread_cond has 2 versions (2.2.5 and 2.3.2).
  // pthread_cond_t has different size in the different versions.
  // If call new REAL functions for old pthread_cond_t, they will corrupt memory
  // after pthread_cond_t (old cond is smaller).
  // If we call old REAL functions for new pthread_cond_t, we will lose  some
  // functionality (e.g. old functions do not support waiting against
  // CLOCK_REALTIME).
  // Proper handling would require to have 2 versions of interceptors as well.
  // But this is messy, in particular requires linker scripts when sanitizer
  // runtime is linked into a shared library.
  // Instead we assume we don't have dynamic libraries built against old
  // pthread (2.2.5 is dated by 2002). And provide legacy_pthread_cond flag
  // that allows to work with old libraries (but this mode does not support
  // some features, e.g. pthread_condattr_getpshared).
  static void *init_cond(void *c, bool force = false) {
    // sizeof(pthread_cond_t) >= sizeof(uptr) in both versions.
    // So we allocate additional memory on the side large enough to hold
    // any pthread_cond_t object. Always call new REAL functions, but pass
    // the aux object to them.
    // Note: the code assumes that PTHREAD_COND_INITIALIZER initializes
    // first word of pthread_cond_t to zero.
    // It's all relevant only for linux.
    if (!common_flags()->legacy_pthread_cond)
      return c;
    atomic_uintptr_t *p = (atomic_uintptr_t*)c;
    uptr cond = atomic_load(p, memory_order_acquire);
    if (!force && cond != 0)
      return (void*)cond;
    void *newcond = WRAP(malloc)(pthread_cond_t_sz);
    internal_memset(newcond, 0, pthread_cond_t_sz);
    if (atomic_compare_exchange_strong(p, &cond, (uptr)newcond,
        memory_order_acq_rel))
      return newcond;
    WRAP(free)(newcond);
    return (void*)cond;
  }
  
  struct CondMutexUnlockCtx {
    ThreadState *thr;
    uptr pc;
    void *m;
  };
  
  static void cond_mutex_unlock(CondMutexUnlockCtx *arg) {
    MutexLock(arg->thr, arg->pc, (uptr)arg->m);
  }
  
  INTERCEPTOR(int, pthread_cond_init, void *c, void *a) {
    void *cond = init_cond(c, true);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_init, cond, a);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), true);
    return REAL(pthread_cond_init)(cond, a);
  }
  
  INTERCEPTOR(int, pthread_cond_wait, void *c, void *m) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_wait, cond, m);
    MutexUnlock(thr, pc, (uptr)m);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
    CondMutexUnlockCtx arg = {thr, pc, m};
    // This ensures that we handle mutex lock even in case of pthread_cancel.
    // See test/tsan/cond_cancel.cc.
    int res = call_pthread_cancel_with_cleanup(
        (int(*)(void *c, void *m, void *abstime))REAL(pthread_cond_wait),
        cond, m, 0, (void(*)(void *arg))cond_mutex_unlock, &arg);
    if (res == errno_EOWNERDEAD)
      MutexRepair(thr, pc, (uptr)m);
    MutexLock(thr, pc, (uptr)m);
    return res;
  }
  
  INTERCEPTOR(int, pthread_cond_timedwait, void *c, void *m, void *abstime) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait, cond, m, abstime);
    MutexUnlock(thr, pc, (uptr)m);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
    CondMutexUnlockCtx arg = {thr, pc, m};
    // This ensures that we handle mutex lock even in case of pthread_cancel.
    // See test/tsan/cond_cancel.cc.
    int res = call_pthread_cancel_with_cleanup(
        REAL(pthread_cond_timedwait), cond, m, abstime,
        (void(*)(void *arg))cond_mutex_unlock, &arg);
    if (res == errno_EOWNERDEAD)
      MutexRepair(thr, pc, (uptr)m);
    MutexLock(thr, pc, (uptr)m);
    return res;
  }
  
  INTERCEPTOR(int, pthread_cond_signal, void *c) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_signal, cond);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
    return REAL(pthread_cond_signal)(cond);
  }
  
  INTERCEPTOR(int, pthread_cond_broadcast, void *c) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_broadcast, cond);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
    return REAL(pthread_cond_broadcast)(cond);
  }
  
  INTERCEPTOR(int, pthread_cond_destroy, void *c) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_destroy, cond);
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), true);
    int res = REAL(pthread_cond_destroy)(cond);
    if (common_flags()->legacy_pthread_cond) {
      // Free our aux cond and zero the pointer to not leave dangling pointers.
      WRAP(free)(cond);
      atomic_store((atomic_uintptr_t*)c, 0, memory_order_relaxed);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_mutex_init, void *m, void *a) {
    SCOPED_TSAN_INTERCEPTOR(pthread_mutex_init, m, a);
    int res = REAL(pthread_mutex_init)(m, a);
    if (res == 0) {
      bool recursive = false;
      if (a) {
        int type = 0;
        if (REAL(pthread_mutexattr_gettype)(a, &type) == 0)
          recursive = (type == PTHREAD_MUTEX_RECURSIVE
              || type == PTHREAD_MUTEX_RECURSIVE_NP);
      }
      MutexCreate(thr, pc, (uptr)m, false, recursive, false);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_mutex_destroy, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_mutex_destroy, m);
    int res = REAL(pthread_mutex_destroy)(m);
    if (res == 0 || res == EBUSY) {
      MutexDestroy(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_mutex_trylock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_mutex_trylock, m);
    int res = REAL(pthread_mutex_trylock)(m);
    if (res == EOWNERDEAD)
      MutexRepair(thr, pc, (uptr)m);
    if (res == 0 || res == EOWNERDEAD)
      MutexLock(thr, pc, (uptr)m, /*rec=*/1, /*try_lock=*/true);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_mutex_timedlock, void *m, void *abstime) {
    SCOPED_TSAN_INTERCEPTOR(pthread_mutex_timedlock, m, abstime);
    int res = REAL(pthread_mutex_timedlock)(m, abstime);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_spin_init, void *m, int pshared) {
    SCOPED_TSAN_INTERCEPTOR(pthread_spin_init, m, pshared);
    int res = REAL(pthread_spin_init)(m, pshared);
    if (res == 0) {
      MutexCreate(thr, pc, (uptr)m, false, false, false);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_spin_destroy, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_spin_destroy, m);
    int res = REAL(pthread_spin_destroy)(m);
    if (res == 0) {
      MutexDestroy(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_spin_lock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_spin_lock, m);
    int res = REAL(pthread_spin_lock)(m);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_spin_trylock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_spin_trylock, m);
    int res = REAL(pthread_spin_trylock)(m);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m, /*rec=*/1, /*try_lock=*/true);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_spin_unlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_spin_unlock, m);
    MutexUnlock(thr, pc, (uptr)m);
    int res = REAL(pthread_spin_unlock)(m);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_init, void *m, void *a) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_init, m, a);
    int res = REAL(pthread_rwlock_init)(m, a);
    if (res == 0) {
      MutexCreate(thr, pc, (uptr)m, true, false, false);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_destroy, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_destroy, m);
    int res = REAL(pthread_rwlock_destroy)(m);
    if (res == 0) {
      MutexDestroy(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_rdlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_rdlock, m);
    int res = REAL(pthread_rwlock_rdlock)(m);
    if (res == 0) {
      MutexReadLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_tryrdlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_tryrdlock, m);
    int res = REAL(pthread_rwlock_tryrdlock)(m);
    if (res == 0) {
      MutexReadLock(thr, pc, (uptr)m, /*try_lock=*/true);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_timedrdlock, void *m, void *abstime) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_timedrdlock, m, abstime);
    int res = REAL(pthread_rwlock_timedrdlock)(m, abstime);
    if (res == 0) {
      MutexReadLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_wrlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_wrlock, m);
    int res = REAL(pthread_rwlock_wrlock)(m);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_trywrlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_trywrlock, m);
    int res = REAL(pthread_rwlock_trywrlock)(m);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m, /*rec=*/1, /*try_lock=*/true);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_timedwrlock, void *m, void *abstime) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_timedwrlock, m, abstime);
    int res = REAL(pthread_rwlock_timedwrlock)(m, abstime);
    if (res == 0) {
      MutexLock(thr, pc, (uptr)m);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_rwlock_unlock, void *m) {
    SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_unlock, m);
    MutexReadOrWriteUnlock(thr, pc, (uptr)m);
    int res = REAL(pthread_rwlock_unlock)(m);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_barrier_init, void *b, void *a, unsigned count) {
    SCOPED_TSAN_INTERCEPTOR(pthread_barrier_init, b, a, count);
    MemoryWrite(thr, pc, (uptr)b, kSizeLog1);
    int res = REAL(pthread_barrier_init)(b, a, count);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_barrier_destroy, void *b) {
    SCOPED_TSAN_INTERCEPTOR(pthread_barrier_destroy, b);
    MemoryWrite(thr, pc, (uptr)b, kSizeLog1);
    int res = REAL(pthread_barrier_destroy)(b);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_barrier_wait, void *b) {
    SCOPED_TSAN_INTERCEPTOR(pthread_barrier_wait, b);
    Release(thr, pc, (uptr)b);
    MemoryRead(thr, pc, (uptr)b, kSizeLog1);
    int res = REAL(pthread_barrier_wait)(b);
    MemoryRead(thr, pc, (uptr)b, kSizeLog1);
    if (res == 0 || res == PTHREAD_BARRIER_SERIAL_THREAD) {
      Acquire(thr, pc, (uptr)b);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_once, void *o, void (*f)()) {
    SCOPED_INTERCEPTOR_RAW(pthread_once, o, f);
    if (o == 0 || f == 0)
      return EINVAL;
    atomic_uint32_t *a = static_cast<atomic_uint32_t*>(o);
    u32 v = atomic_load(a, memory_order_acquire);
    if (v == 0 && atomic_compare_exchange_strong(a, &v, 1,
                                                 memory_order_relaxed)) {
      (*f)();
      if (!thr->in_ignored_lib)
        Release(thr, pc, (uptr)o);
      atomic_store(a, 2, memory_order_release);
    } else {
      while (v != 2) {
        pthread_yield();
        v = atomic_load(a, memory_order_acquire);
      }
      if (!thr->in_ignored_lib)
        Acquire(thr, pc, (uptr)o);
    }
    return 0;
  }
  
  TSAN_INTERCEPTOR(int, sem_init, void *s, int pshared, unsigned value) {
    SCOPED_TSAN_INTERCEPTOR(sem_init, s, pshared, value);
    int res = REAL(sem_init)(s, pshared, value);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_destroy, void *s) {
    SCOPED_TSAN_INTERCEPTOR(sem_destroy, s);
    int res = REAL(sem_destroy)(s);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_wait, void *s) {
    SCOPED_TSAN_INTERCEPTOR(sem_wait, s);
    int res = BLOCK_REAL(sem_wait)(s);
    if (res == 0) {
      Acquire(thr, pc, (uptr)s);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_trywait, void *s) {
    SCOPED_TSAN_INTERCEPTOR(sem_trywait, s);
    int res = BLOCK_REAL(sem_trywait)(s);
    if (res == 0) {
      Acquire(thr, pc, (uptr)s);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_timedwait, void *s, void *abstime) {
    SCOPED_TSAN_INTERCEPTOR(sem_timedwait, s, abstime);
    int res = BLOCK_REAL(sem_timedwait)(s, abstime);
    if (res == 0) {
      Acquire(thr, pc, (uptr)s);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_post, void *s) {
    SCOPED_TSAN_INTERCEPTOR(sem_post, s);
    Release(thr, pc, (uptr)s);
    int res = REAL(sem_post)(s);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, sem_getvalue, void *s, int *sval) {
    SCOPED_TSAN_INTERCEPTOR(sem_getvalue, s, sval);
    int res = REAL(sem_getvalue)(s, sval);
    if (res == 0) {
      Acquire(thr, pc, (uptr)s);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, __xstat, int version, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__xstat, version, path, buf);
    return REAL(__xstat)(version, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, stat, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__xstat, 0, path, buf);
    return REAL(__xstat)(0, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, __xstat64, int version, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__xstat64, version, path, buf);
    return REAL(__xstat64)(version, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, stat64, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__xstat64, 0, path, buf);
    return REAL(__xstat64)(0, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, __lxstat, int version, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__lxstat, version, path, buf);
    return REAL(__lxstat)(version, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, lstat, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__lxstat, 0, path, buf);
    return REAL(__lxstat)(0, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, __lxstat64, int version, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__lxstat64, version, path, buf);
    return REAL(__lxstat64)(version, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, lstat64, const char *path, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__lxstat64, 0, path, buf);
    return REAL(__lxstat64)(0, path, buf);
  }
  
  TSAN_INTERCEPTOR(int, __fxstat, int version, int fd, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__fxstat, version, fd, buf);
    if (fd > 0)
      FdAccess(thr, pc, fd);
    return REAL(__fxstat)(version, fd, buf);
  }
  
  TSAN_INTERCEPTOR(int, fstat, int fd, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__fxstat, 0, fd, buf);
    if (fd > 0)
      FdAccess(thr, pc, fd);
    return REAL(__fxstat)(0, fd, buf);
  }
  
  TSAN_INTERCEPTOR(int, __fxstat64, int version, int fd, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__fxstat64, version, fd, buf);
    if (fd > 0)
      FdAccess(thr, pc, fd);
    return REAL(__fxstat64)(version, fd, buf);
  }
  
  TSAN_INTERCEPTOR(int, fstat64, int fd, void *buf) {
    SCOPED_TSAN_INTERCEPTOR(__fxstat64, 0, fd, buf);
    if (fd > 0)
      FdAccess(thr, pc, fd);
    return REAL(__fxstat64)(0, fd, buf);
  }
  
  TSAN_INTERCEPTOR(int, open, const char *name, int flags, int mode) {
    SCOPED_TSAN_INTERCEPTOR(open, name, flags, mode);
    int fd = REAL(open)(name, flags, mode);
    if (fd >= 0)
      FdFileCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, open64, const char *name, int flags, int mode) {
    SCOPED_TSAN_INTERCEPTOR(open64, name, flags, mode);
    int fd = REAL(open64)(name, flags, mode);
    if (fd >= 0)
      FdFileCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, creat, const char *name, int mode) {
    SCOPED_TSAN_INTERCEPTOR(creat, name, mode);
    int fd = REAL(creat)(name, mode);
    if (fd >= 0)
      FdFileCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, creat64, const char *name, int mode) {
    SCOPED_TSAN_INTERCEPTOR(creat64, name, mode);
    int fd = REAL(creat64)(name, mode);
    if (fd >= 0)
      FdFileCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, dup, int oldfd) {
    SCOPED_TSAN_INTERCEPTOR(dup, oldfd);
    int newfd = REAL(dup)(oldfd);
    if (oldfd >= 0 && newfd >= 0 && newfd != oldfd)
      FdDup(thr, pc, oldfd, newfd);
    return newfd;
  }
  
  TSAN_INTERCEPTOR(int, dup2, int oldfd, int newfd) {
    SCOPED_TSAN_INTERCEPTOR(dup2, oldfd, newfd);
    int newfd2 = REAL(dup2)(oldfd, newfd);
    if (oldfd >= 0 && newfd2 >= 0 && newfd2 != oldfd)
      FdDup(thr, pc, oldfd, newfd2);
    return newfd2;
  }
  
  TSAN_INTERCEPTOR(int, dup3, int oldfd, int newfd, int flags) {
    SCOPED_TSAN_INTERCEPTOR(dup3, oldfd, newfd, flags);
    int newfd2 = REAL(dup3)(oldfd, newfd, flags);
    if (oldfd >= 0 && newfd2 >= 0 && newfd2 != oldfd)
      FdDup(thr, pc, oldfd, newfd2);
    return newfd2;
  }
  
  TSAN_INTERCEPTOR(int, eventfd, unsigned initval, int flags) {
    SCOPED_TSAN_INTERCEPTOR(eventfd, initval, flags);
    int fd = REAL(eventfd)(initval, flags);
    if (fd >= 0)
      FdEventCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, signalfd, int fd, void *mask, int flags) {
    SCOPED_TSAN_INTERCEPTOR(signalfd, fd, mask, flags);
    if (fd >= 0)
      FdClose(thr, pc, fd);
    fd = REAL(signalfd)(fd, mask, flags);
    if (fd >= 0)
      FdSignalCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, inotify_init, int fake) {
    SCOPED_TSAN_INTERCEPTOR(inotify_init, fake);
    int fd = REAL(inotify_init)(fake);
    if (fd >= 0)
      FdInotifyCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, inotify_init1, int flags) {
    SCOPED_TSAN_INTERCEPTOR(inotify_init1, flags);
    int fd = REAL(inotify_init1)(flags);
    if (fd >= 0)
      FdInotifyCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, socket, int domain, int type, int protocol) {
    SCOPED_TSAN_INTERCEPTOR(socket, domain, type, protocol);
    int fd = REAL(socket)(domain, type, protocol);
    if (fd >= 0)
      FdSocketCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, socketpair, int domain, int type, int protocol, int *fd) {
    SCOPED_TSAN_INTERCEPTOR(socketpair, domain, type, protocol, fd);
    int res = REAL(socketpair)(domain, type, protocol, fd);
    if (res == 0 && fd[0] >= 0 && fd[1] >= 0)
      FdPipeCreate(thr, pc, fd[0], fd[1]);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, connect, int fd, void *addr, unsigned addrlen) {
    SCOPED_TSAN_INTERCEPTOR(connect, fd, addr, addrlen);
    FdSocketConnecting(thr, pc, fd);
    int res = REAL(connect)(fd, addr, addrlen);
    if (res == 0 && fd >= 0)
      FdSocketConnect(thr, pc, fd);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, bind, int fd, void *addr, unsigned addrlen) {
    SCOPED_TSAN_INTERCEPTOR(bind, fd, addr, addrlen);
    int res = REAL(bind)(fd, addr, addrlen);
    if (fd > 0 && res == 0)
      FdAccess(thr, pc, fd);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, listen, int fd, int backlog) {
    SCOPED_TSAN_INTERCEPTOR(listen, fd, backlog);
    int res = REAL(listen)(fd, backlog);
    if (fd > 0 && res == 0)
      FdAccess(thr, pc, fd);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, epoll_create, int size) {
    SCOPED_TSAN_INTERCEPTOR(epoll_create, size);
    int fd = REAL(epoll_create)(size);
    if (fd >= 0)
      FdPollCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, epoll_create1, int flags) {
    SCOPED_TSAN_INTERCEPTOR(epoll_create1, flags);
    int fd = REAL(epoll_create1)(flags);
    if (fd >= 0)
      FdPollCreate(thr, pc, fd);
    return fd;
  }
  
  TSAN_INTERCEPTOR(int, close, int fd) {
    SCOPED_TSAN_INTERCEPTOR(close, fd);
    if (fd >= 0)
      FdClose(thr, pc, fd);
    return REAL(close)(fd);
  }
  
  TSAN_INTERCEPTOR(int, __close, int fd) {
    SCOPED_TSAN_INTERCEPTOR(__close, fd);
    if (fd >= 0)
      FdClose(thr, pc, fd);
    return REAL(__close)(fd);
  }
  
  // glibc guts
  TSAN_INTERCEPTOR(void, __res_iclose, void *state, bool free_addr) {
    SCOPED_TSAN_INTERCEPTOR(__res_iclose, state, free_addr);
    int fds[64];
    int cnt = ExtractResolvFDs(state, fds, ARRAY_SIZE(fds));
    for (int i = 0; i < cnt; i++) {
      if (fds[i] > 0)
        FdClose(thr, pc, fds[i]);
    }
    REAL(__res_iclose)(state, free_addr);
  }
  
  TSAN_INTERCEPTOR(int, pipe, int *pipefd) {
    SCOPED_TSAN_INTERCEPTOR(pipe, pipefd);
    int res = REAL(pipe)(pipefd);
    if (res == 0 && pipefd[0] >= 0 && pipefd[1] >= 0)
      FdPipeCreate(thr, pc, pipefd[0], pipefd[1]);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pipe2, int *pipefd, int flags) {
    SCOPED_TSAN_INTERCEPTOR(pipe2, pipefd, flags);
    int res = REAL(pipe2)(pipefd, flags);
    if (res == 0 && pipefd[0] >= 0 && pipefd[1] >= 0)
      FdPipeCreate(thr, pc, pipefd[0], pipefd[1]);
    return res;
  }
  
  TSAN_INTERCEPTOR(long_t, send, int fd, void *buf, long_t len, int flags) {
    SCOPED_TSAN_INTERCEPTOR(send, fd, buf, len, flags);
    if (fd >= 0) {
      FdAccess(thr, pc, fd);
      FdRelease(thr, pc, fd);
    }
    int res = REAL(send)(fd, buf, len, flags);
    return res;
  }
  
  TSAN_INTERCEPTOR(long_t, sendmsg, int fd, void *msg, int flags) {
    SCOPED_TSAN_INTERCEPTOR(sendmsg, fd, msg, flags);
    if (fd >= 0) {
      FdAccess(thr, pc, fd);
      FdRelease(thr, pc, fd);
    }
    int res = REAL(sendmsg)(fd, msg, flags);
    return res;
  }
  
  TSAN_INTERCEPTOR(long_t, recv, int fd, void *buf, long_t len, int flags) {
    SCOPED_TSAN_INTERCEPTOR(recv, fd, buf, len, flags);
    if (fd >= 0)
      FdAccess(thr, pc, fd);
    int res = REAL(recv)(fd, buf, len, flags);
    if (res >= 0 && fd >= 0) {
      FdAcquire(thr, pc, fd);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, unlink, char *path) {
    SCOPED_TSAN_INTERCEPTOR(unlink, path);
    Release(thr, pc, File2addr(path));
    int res = REAL(unlink)(path);
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, tmpfile, int fake) {
    SCOPED_TSAN_INTERCEPTOR(tmpfile, fake);
    void *res = REAL(tmpfile)(fake);
    if (res) {
      int fd = fileno_unlocked(res);
      if (fd >= 0)
        FdFileCreate(thr, pc, fd);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, tmpfile64, int fake) {
    SCOPED_TSAN_INTERCEPTOR(tmpfile64, fake);
    void *res = REAL(tmpfile64)(fake);
    if (res) {
      int fd = fileno_unlocked(res);
      if (fd >= 0)
        FdFileCreate(thr, pc, fd);
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(uptr, fread, void *ptr, uptr size, uptr nmemb, void *f) {
    // libc file streams can call user-supplied functions, see fopencookie.
    {
      SCOPED_TSAN_INTERCEPTOR(fread, ptr, size, nmemb, f);
      MemoryAccessRange(thr, pc, (uptr)ptr, size * nmemb, true);
    }
    return REAL(fread)(ptr, size, nmemb, f);
  }
  
  TSAN_INTERCEPTOR(uptr, fwrite, const void *p, uptr size, uptr nmemb, void *f) {
    // libc file streams can call user-supplied functions, see fopencookie.
    {
      SCOPED_TSAN_INTERCEPTOR(fwrite, p, size, nmemb, f);
      MemoryAccessRange(thr, pc, (uptr)p, size * nmemb, false);
    }
    return REAL(fwrite)(p, size, nmemb, f);
  }
  
  TSAN_INTERCEPTOR(void, abort, int fake) {
    SCOPED_TSAN_INTERCEPTOR(abort, fake);
    REAL(fflush)(0);
    REAL(abort)(fake);
  }
  
  TSAN_INTERCEPTOR(int, puts, const char *s) {
    SCOPED_TSAN_INTERCEPTOR(puts, s);
    MemoryAccessRange(thr, pc, (uptr)s, internal_strlen(s), false);
    return REAL(puts)(s);
  }
  
  TSAN_INTERCEPTOR(int, rmdir, char *path) {
    SCOPED_TSAN_INTERCEPTOR(rmdir, path);
    Release(thr, pc, Dir2addr(path));
    int res = REAL(rmdir)(path);
    return res;
  }
  
  TSAN_INTERCEPTOR(void*, opendir, char *path) {
    SCOPED_TSAN_INTERCEPTOR(opendir, path);
    void *res = REAL(opendir)(path);
    if (res != 0)
      Acquire(thr, pc, Dir2addr(path));
    return res;
  }
  
  TSAN_INTERCEPTOR(int, epoll_ctl, int epfd, int op, int fd, void *ev) {
    SCOPED_TSAN_INTERCEPTOR(epoll_ctl, epfd, op, fd, ev);
    if (epfd >= 0)
      FdAccess(thr, pc, epfd);
    if (epfd >= 0 && fd >= 0)
      FdAccess(thr, pc, fd);
    if (op == EPOLL_CTL_ADD && epfd >= 0)
      FdRelease(thr, pc, epfd);
    int res = REAL(epoll_ctl)(epfd, op, fd, ev);
    return res;
  }
  
  TSAN_INTERCEPTOR(int, epoll_wait, int epfd, void *ev, int cnt, int timeout) {
    SCOPED_TSAN_INTERCEPTOR(epoll_wait, epfd, ev, cnt, timeout);
    if (epfd >= 0)
      FdAccess(thr, pc, epfd);
    int res = BLOCK_REAL(epoll_wait)(epfd, ev, cnt, timeout);
    if (res > 0 && epfd >= 0)
      FdAcquire(thr, pc, epfd);
    return res;
  }
  
  namespace __tsan {
  
  static void CallUserSignalHandler(ThreadState *thr, bool sync, bool sigact,
      int sig, my_siginfo_t *info, void *uctx) {
    // Ensure that the handler does not spoil errno.
    const int saved_errno = errno;
    errno = 99;
    // Need to remember pc before the call, because the handler can reset it.
    uptr pc = sigact ?
       (uptr)sigactions[sig].sa_sigaction :
       (uptr)sigactions[sig].sa_handler;
    pc += 1;  // return address is expected, OutputReport() will undo this
    if (sigact)
      sigactions[sig].sa_sigaction(sig, info, uctx);
    else
      sigactions[sig].sa_handler(sig);
    // We do not detect errno spoiling for SIGTERM,
    // because some SIGTERM handlers do spoil errno but reraise SIGTERM,
    // tsan reports false positive in such case.
    // It's difficult to properly detect this situation (reraise),
    // because in async signal processing case (when handler is called directly
    // from rtl_generic_sighandler) we have not yet received the reraised
    // signal; and it looks too fragile to intercept all ways to reraise a signal.
    if (flags()->report_bugs && !sync && sig != SIGTERM && errno != 99) {
      __tsan::StackTrace stack;
      stack.ObtainCurrent(thr, pc);
      ThreadRegistryLock l(ctx->thread_registry);
      ScopedReport rep(ReportTypeErrnoInSignal);
      if (!IsFiredSuppression(ctx, rep, stack)) {
        rep.AddStack(&stack, true);
        OutputReport(thr, rep);
      }
    }
    errno = saved_errno;
  }
  
  void ProcessPendingSignals(ThreadState *thr) {
    SignalContext *sctx = SigCtx(thr);
    if (sctx == 0 || sctx->pending_signal_count == 0 || thr->in_signal_handler)
      return;
    thr->in_signal_handler = true;
    sctx->pending_signal_count = 0;
    // These are too big for stack.
    static THREADLOCAL __sanitizer_sigset_t emptyset, oldset;
    REAL(sigfillset)(&emptyset);
    pthread_sigmask(SIG_SETMASK, &emptyset, &oldset);
    for (int sig = 0; sig < kSigCount; sig++) {
      SignalDesc *signal = &sctx->pending_signals[sig];
      if (signal->armed) {
        signal->armed = false;
        if (sigactions[sig].sa_handler != SIG_DFL
            && sigactions[sig].sa_handler != SIG_IGN) {
          CallUserSignalHandler(thr, false, signal->sigaction,
              sig, &signal->siginfo, &signal->ctx);
        }
      }
    }
    pthread_sigmask(SIG_SETMASK, &oldset, 0);
    CHECK_EQ(thr->in_signal_handler, true);
    thr->in_signal_handler = false;
  }
  
  }  // namespace __tsan
  
  static bool is_sync_signal(SignalContext *sctx, int sig) {
    return sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
        sig == SIGABRT || sig == SIGFPE || sig == SIGPIPE || sig == SIGSYS ||
        // If we are sending signal to ourselves, we must process it now.
        (sctx && sig == sctx->int_signal_send);
  }
  
  void ALWAYS_INLINE rtl_generic_sighandler(bool sigact, int sig,
      my_siginfo_t *info, void *ctx) {
    ThreadState *thr = cur_thread();
    SignalContext *sctx = SigCtx(thr);
    if (sig < 0 || sig >= kSigCount) {
      VPrintf(1, "ThreadSanitizer: ignoring signal %d\n", sig);
      return;
    }
    // Don't mess with synchronous signals.
    const bool sync = is_sync_signal(sctx, sig);
    if (sync ||
        // If we are in blocking function, we can safely process it now
        // (but check if we are in a recursive interceptor,
        // i.e. pthread_join()->munmap()).
        (sctx && sctx->in_blocking_func == 1)) {
      CHECK_EQ(thr->in_signal_handler, false);
      thr->in_signal_handler = true;
      if (sctx && sctx->in_blocking_func == 1) {
        // We ignore interceptors in blocking functions,
        // temporary enbled them again while we are calling user function.
        int const i = thr->ignore_interceptors;
        thr->ignore_interceptors = 0;
        CallUserSignalHandler(thr, sync, sigact, sig, info, ctx);
        thr->ignore_interceptors = i;
      } else {
        CallUserSignalHandler(thr, sync, sigact, sig, info, ctx);
      }
      CHECK_EQ(thr->in_signal_handler, true);
      thr->in_signal_handler = false;
      return;
    }
  
    if (sctx == 0)
      return;
    SignalDesc *signal = &sctx->pending_signals[sig];
    if (signal->armed == false) {
      signal->armed = true;
      signal->sigaction = sigact;
      if (info)
        internal_memcpy(&signal->siginfo, info, sizeof(*info));
      if (ctx)
        internal_memcpy(&signal->ctx, ctx, sizeof(signal->ctx));
      sctx->pending_signal_count++;
    }
  }
  
  static void rtl_sighandler(int sig) {
    rtl_generic_sighandler(false, sig, 0, 0);
  }
  
  static void rtl_sigaction(int sig, my_siginfo_t *info, void *ctx) {
    rtl_generic_sighandler(true, sig, info, ctx);
  }
  
  TSAN_INTERCEPTOR(int, sigaction, int sig, sigaction_t *act, sigaction_t *old) {
    SCOPED_TSAN_INTERCEPTOR(sigaction, sig, act, old);
    if (old)
      internal_memcpy(old, &sigactions[sig], sizeof(*old));
    if (act == 0)
      return 0;
    internal_memcpy(&sigactions[sig], act, sizeof(*act));
    sigaction_t newact;
    internal_memcpy(&newact, act, sizeof(newact));
    REAL(sigfillset)(&newact.sa_mask);
    if (act->sa_handler != SIG_IGN && act->sa_handler != SIG_DFL) {
      if (newact.sa_flags & SA_SIGINFO)
        newact.sa_sigaction = rtl_sigaction;
      else
        newact.sa_handler = rtl_sighandler;
    }
    int res = REAL(sigaction)(sig, &newact, 0);
    return res;
  }
  
  TSAN_INTERCEPTOR(sighandler_t, signal, int sig, sighandler_t h) {
    sigaction_t act;
    act.sa_handler = h;
    REAL(memset)(&act.sa_mask, -1, sizeof(act.sa_mask));
    act.sa_flags = 0;
    sigaction_t old;
    int res = sigaction(sig, &act, &old);
    if (res)
      return SIG_ERR;
    return old.sa_handler;
  }
  
  TSAN_INTERCEPTOR(int, sigsuspend, const __sanitizer_sigset_t *mask) {
    SCOPED_TSAN_INTERCEPTOR(sigsuspend, mask);
    return REAL(sigsuspend)(mask);
  }
  
  TSAN_INTERCEPTOR(int, raise, int sig) {
    SCOPED_TSAN_INTERCEPTOR(raise, sig);
    SignalContext *sctx = SigCtx(thr);
    CHECK_NE(sctx, 0);
    int prev = sctx->int_signal_send;
    sctx->int_signal_send = sig;
    int res = REAL(raise)(sig);
    CHECK_EQ(sctx->int_signal_send, sig);
    sctx->int_signal_send = prev;
    return res;
  }
  
  TSAN_INTERCEPTOR(int, kill, int pid, int sig) {
    SCOPED_TSAN_INTERCEPTOR(kill, pid, sig);
    SignalContext *sctx = SigCtx(thr);
    CHECK_NE(sctx, 0);
    int prev = sctx->int_signal_send;
    if (pid == (int)internal_getpid()) {
      sctx->int_signal_send = sig;
    }
    int res = REAL(kill)(pid, sig);
    if (pid == (int)internal_getpid()) {
      CHECK_EQ(sctx->int_signal_send, sig);
      sctx->int_signal_send = prev;
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, pthread_kill, void *tid, int sig) {
    SCOPED_TSAN_INTERCEPTOR(pthread_kill, tid, sig);
    SignalContext *sctx = SigCtx(thr);
    CHECK_NE(sctx, 0);
    int prev = sctx->int_signal_send;
    if (tid == pthread_self()) {
      sctx->int_signal_send = sig;
    }
    int res = REAL(pthread_kill)(tid, sig);
    if (tid == pthread_self()) {
      CHECK_EQ(sctx->int_signal_send, sig);
      sctx->int_signal_send = prev;
    }
    return res;
  }
  
  TSAN_INTERCEPTOR(int, gettimeofday, void *tv, void *tz) {
    SCOPED_TSAN_INTERCEPTOR(gettimeofday, tv, tz);
    // It's intercepted merely to process pending signals.
    return REAL(gettimeofday)(tv, tz);
  }
  
  TSAN_INTERCEPTOR(int, getaddrinfo, void *node, void *service,
      void *hints, void *rv) {
    SCOPED_TSAN_INTERCEPTOR(getaddrinfo, node, service, hints, rv);
    // We miss atomic synchronization in getaddrinfo,
    // and can report false race between malloc and free
    // inside of getaddrinfo. So ignore memory accesses.
    ThreadIgnoreBegin(thr, pc);
    int res = REAL(getaddrinfo)(node, service, hints, rv);
    ThreadIgnoreEnd(thr, pc);
    return res;
  }
  
  // Linux kernel has a bug that leads to kernel deadlock if a process
  // maps TBs of memory and then calls mlock().
  static void MlockIsUnsupported() {
    static atomic_uint8_t printed;
    if (atomic_exchange(&printed, 1, memory_order_relaxed))
      return;
    VPrintf(1, "INFO: ThreadSanitizer ignores mlock/munlock[all]\n");
  }
  
  TSAN_INTERCEPTOR(int, mlock, const void *addr, uptr len) {
    MlockIsUnsupported();
    return 0;
  }
  
  TSAN_INTERCEPTOR(int, munlock, const void *addr, uptr len) {
    MlockIsUnsupported();
    return 0;
  }
  
  TSAN_INTERCEPTOR(int, mlockall, int flags) {
    MlockIsUnsupported();
    return 0;
  }
  
  TSAN_INTERCEPTOR(int, munlockall, void) {
    MlockIsUnsupported();
    return 0;
  }
  
  TSAN_INTERCEPTOR(int, fork, int fake) {
    if (cur_thread()->in_symbolizer)
      return REAL(fork)(fake);
    SCOPED_INTERCEPTOR_RAW(fork, fake);
    ForkBefore(thr, pc);
    int pid = REAL(fork)(fake);
    if (pid == 0) {
      // child
      ForkChildAfter(thr, pc);
      FdOnFork(thr, pc);
    } else if (pid > 0) {
      // parent
      ForkParentAfter(thr, pc);
    } else {
      // error
      ForkParentAfter(thr, pc);
    }
    return pid;
  }
  
  TSAN_INTERCEPTOR(int, vfork, int fake) {
    // Some programs (e.g. openjdk) call close for all file descriptors
    // in the child process. Under tsan it leads to false positives, because
    // address space is shared, so the parent process also thinks that
    // the descriptors are closed (while they are actually not).
    // This leads to false positives due to missed synchronization.
    // Strictly saying this is undefined behavior, because vfork child is not
    // allowed to call any functions other than exec/exit. But this is what
    // openjdk does, so we want to handle it.
    // We could disable interceptors in the child process. But it's not possible
    // to simply intercept and wrap vfork, because vfork child is not allowed
    // to return from the function that calls vfork, and that's exactly what
    // we would do. So this would require some assembly trickery as well.
    // Instead we simply turn vfork into fork.
    return WRAP(fork)(fake);
  }
  
  static int OnExit(ThreadState *thr) {
    int status = Finalize(thr);
    REAL(fflush)(0);
    return status;
  }
  
  struct TsanInterceptorContext {
    ThreadState *thr;
    const uptr caller_pc;
    const uptr pc;
  };
  
  static void HandleRecvmsg(ThreadState *thr, uptr pc,
      __sanitizer_msghdr *msg) {
    int fds[64];
    int cnt = ExtractRecvmsgFDs(msg, fds, ARRAY_SIZE(fds));
    for (int i = 0; i < cnt; i++)
      FdEventCreate(thr, pc, fds[i]);
  }
  
  #include "sanitizer_common/sanitizer_platform_interceptors.h"
  // Causes interceptor recursion (getaddrinfo() and fopen())
  #undef SANITIZER_INTERCEPT_GETADDRINFO
  
  #define COMMON_INTERCEPT_FUNCTION(name) INTERCEPT_FUNCTION(name)
  
  #define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size)                    \
    MemoryAccessRange(((TsanInterceptorContext *)ctx)->thr,                 \
                      ((TsanInterceptorContext *)ctx)->pc, (uptr)ptr, size, \
                      true)
  
  #define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size)                       \
    MemoryAccessRange(((TsanInterceptorContext *) ctx)->thr,                  \
                      ((TsanInterceptorContext *) ctx)->pc, (uptr) ptr, size, \
                      false)
  
  #define COMMON_INTERCEPTOR_ENTER(ctx, func, ...)      \
    SCOPED_TSAN_INTERCEPTOR(func, __VA_ARGS__);         \
    TsanInterceptorContext _ctx = {thr, caller_pc, pc}; \
    ctx = (void *)&_ctx;                                \
    (void) ctx;
  
  #define COMMON_INTERCEPTOR_ENTER_NOIGNORE(ctx, func, ...) \
    SCOPED_INTERCEPTOR_RAW(func, __VA_ARGS__);              \
    TsanInterceptorContext _ctx = {thr, caller_pc, pc};     \
    ctx = (void *)&_ctx;                                    \
    (void) ctx;
  
  #define COMMON_INTERCEPTOR_FILE_OPEN(ctx, file, path) \
    Acquire(thr, pc, File2addr(path));                  \
    if (file) {                                         \
      int fd = fileno_unlocked(file);                   \
      if (fd >= 0) FdFileCreate(thr, pc, fd);           \
    }
  
  #define COMMON_INTERCEPTOR_FILE_CLOSE(ctx, file) \
    if (file) {                                    \
      int fd = fileno_unlocked(file);              \
      if (fd >= 0) FdClose(thr, pc, fd);           \
    }
  
  #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, res)  \
    libignore()->OnLibraryLoaded(filename)
  
  #define COMMON_INTERCEPTOR_LIBRARY_UNLOADED() \
    libignore()->OnLibraryUnloaded()
  
  #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
    FdAcquire(((TsanInterceptorContext *) ctx)->thr, pc, fd)
  
  #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
    FdRelease(((TsanInterceptorContext *) ctx)->thr, pc, fd)
  
  #define COMMON_INTERCEPTOR_FD_ACCESS(ctx, fd) \
    FdAccess(((TsanInterceptorContext *) ctx)->thr, pc, fd)
  
  #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
    FdSocketAccept(((TsanInterceptorContext *) ctx)->thr, pc, fd, newfd)
  
  #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) \
    ThreadSetName(((TsanInterceptorContext *) ctx)->thr, name)
  
  #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \
    __tsan::ctx->thread_registry->SetThreadNameByUserId(thread, name)
  
  #define COMMON_INTERCEPTOR_BLOCK_REAL(name) BLOCK_REAL(name)
  
  #define COMMON_INTERCEPTOR_ON_EXIT(ctx) \
    OnExit(((TsanInterceptorContext *) ctx)->thr)
  
  #define COMMON_INTERCEPTOR_MUTEX_LOCK(ctx, m) \
    MutexLock(((TsanInterceptorContext *)ctx)->thr, \
              ((TsanInterceptorContext *)ctx)->pc, (uptr)m)
  
  #define COMMON_INTERCEPTOR_MUTEX_UNLOCK(ctx, m) \
    MutexUnlock(((TsanInterceptorContext *)ctx)->thr, \
              ((TsanInterceptorContext *)ctx)->pc, (uptr)m)
  
  #define COMMON_INTERCEPTOR_MUTEX_REPAIR(ctx, m) \
    MutexRepair(((TsanInterceptorContext *)ctx)->thr, \
              ((TsanInterceptorContext *)ctx)->pc, (uptr)m)
  
  #define COMMON_INTERCEPTOR_HANDLE_RECVMSG(ctx, msg) \
    HandleRecvmsg(((TsanInterceptorContext *)ctx)->thr, \
        ((TsanInterceptorContext *)ctx)->pc, msg)
  
  #include "sanitizer_common/sanitizer_common_interceptors.inc"
  
  #define TSAN_SYSCALL() \
    ThreadState *thr = cur_thread(); \
    if (thr->ignore_interceptors) \
      return; \
    ScopedSyscall scoped_syscall(thr) \
  /**/
  
  struct ScopedSyscall {
    ThreadState *thr;
  
    explicit ScopedSyscall(ThreadState *thr)
        : thr(thr) {
      Initialize(thr);
    }
  
    ~ScopedSyscall() {
      ProcessPendingSignals(thr);
    }
  };
  
  static void syscall_access_range(uptr pc, uptr p, uptr s, bool write) {
    TSAN_SYSCALL();
    MemoryAccessRange(thr, pc, p, s, write);
  }
  
  static void syscall_acquire(uptr pc, uptr addr) {
    TSAN_SYSCALL();
    Acquire(thr, pc, addr);
    DPrintf("syscall_acquire(%p)\n", addr);
  }
  
  static void syscall_release(uptr pc, uptr addr) {
    TSAN_SYSCALL();
    DPrintf("syscall_release(%p)\n", addr);
    Release(thr, pc, addr);
  }
  
  static void syscall_fd_close(uptr pc, int fd) {
    TSAN_SYSCALL();
    FdClose(thr, pc, fd);
  }
  
  static USED void syscall_fd_acquire(uptr pc, int fd) {
    TSAN_SYSCALL();
    FdAcquire(thr, pc, fd);
    DPrintf("syscall_fd_acquire(%p)\n", fd);
  }
  
  static USED void syscall_fd_release(uptr pc, int fd) {
    TSAN_SYSCALL();
    DPrintf("syscall_fd_release(%p)\n", fd);
    FdRelease(thr, pc, fd);
  }
  
  static void syscall_pre_fork(uptr pc) {
    TSAN_SYSCALL();
    ForkBefore(thr, pc);
  }
  
  static void syscall_post_fork(uptr pc, int pid) {
    TSAN_SYSCALL();
    if (pid == 0) {
      // child
      ForkChildAfter(thr, pc);
      FdOnFork(thr, pc);
    } else if (pid > 0) {
      // parent
      ForkParentAfter(thr, pc);
    } else {
      // error
      ForkParentAfter(thr, pc);
    }
  }
  
  #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) \
    syscall_access_range(GET_CALLER_PC(), (uptr)(p), (uptr)(s), false)
  
  #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) \
    syscall_access_range(GET_CALLER_PC(), (uptr)(p), (uptr)(s), true)
  
  #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
    do {                                       \
      (void)(p);                               \
      (void)(s);                               \
    } while (false)
  
  #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \
    do {                                        \
      (void)(p);                                \
      (void)(s);                                \
    } while (false)
  
  #define COMMON_SYSCALL_ACQUIRE(addr) \
      syscall_acquire(GET_CALLER_PC(), (uptr)(addr))
  
  #define COMMON_SYSCALL_RELEASE(addr) \
      syscall_release(GET_CALLER_PC(), (uptr)(addr))
  
  #define COMMON_SYSCALL_FD_CLOSE(fd) syscall_fd_close(GET_CALLER_PC(), fd)
  
  #define COMMON_SYSCALL_FD_ACQUIRE(fd) syscall_fd_acquire(GET_CALLER_PC(), fd)
  
  #define COMMON_SYSCALL_FD_RELEASE(fd) syscall_fd_release(GET_CALLER_PC(), fd)
  
  #define COMMON_SYSCALL_PRE_FORK() \
    syscall_pre_fork(GET_CALLER_PC())
  
  #define COMMON_SYSCALL_POST_FORK(res) \
    syscall_post_fork(GET_CALLER_PC(), res)
  
  #include "sanitizer_common/sanitizer_common_syscalls.inc"
  
  namespace __tsan {
  
  static void finalize(void *arg) {
    ThreadState *thr = cur_thread();
    uptr pc = 0;
    atexit_ctx->exit(thr, pc);
    int status = Finalize(thr);
    // Make sure the output is not lost.
    // Flushing all the streams here may freeze the process if a child thread is
    // performing file stream operations at the same time.
    REAL(fflush)(stdout);
    REAL(fflush)(stderr);
    if (status)
      REAL(_exit)(status);
  }
  
  static void unreachable() {
    Report("FATAL: ThreadSanitizer: unreachable called\n");
    Die();
  }
  
  void InitializeInterceptors() {
    // We need to setup it early, because functions like dlsym() can call it.
    REAL(memset) = internal_memset;
    REAL(memcpy) = internal_memcpy;
    REAL(memcmp) = internal_memcmp;
  
    // Instruct libc malloc to consume less memory.
    mallopt(1, 0);  // M_MXFAST
    mallopt(-3, 32*1024);  // M_MMAP_THRESHOLD
  
    InitializeCommonInterceptors();
  
    // We can not use TSAN_INTERCEPT to get setjmp addr,
    // because it does &setjmp and setjmp is not present in some versions of libc.
    using __interception::GetRealFunctionAddress;
    GetRealFunctionAddress("setjmp", (uptr*)&REAL(setjmp), 0, 0);
    GetRealFunctionAddress("_setjmp", (uptr*)&REAL(_setjmp), 0, 0);
    GetRealFunctionAddress("sigsetjmp", (uptr*)&REAL(sigsetjmp), 0, 0);
    GetRealFunctionAddress("__sigsetjmp", (uptr*)&REAL(__sigsetjmp), 0, 0);
  
    TSAN_INTERCEPT(longjmp);
    TSAN_INTERCEPT(siglongjmp);
  
    TSAN_INTERCEPT(malloc);
    TSAN_INTERCEPT(__libc_memalign);
    TSAN_INTERCEPT(calloc);
    TSAN_INTERCEPT(realloc);
    TSAN_INTERCEPT(free);
    TSAN_INTERCEPT(cfree);
    TSAN_INTERCEPT(mmap);
    TSAN_INTERCEPT(mmap64);
    TSAN_INTERCEPT(munmap);
    TSAN_INTERCEPT(memalign);
    TSAN_INTERCEPT(valloc);
    TSAN_INTERCEPT(pvalloc);
    TSAN_INTERCEPT(posix_memalign);
  
    TSAN_INTERCEPT(strlen);
    TSAN_INTERCEPT(memset);
    TSAN_INTERCEPT(memcpy);
    TSAN_INTERCEPT(memmove);
    TSAN_INTERCEPT(memcmp);
    TSAN_INTERCEPT(strchr);
    TSAN_INTERCEPT(strchrnul);
    TSAN_INTERCEPT(strrchr);
    TSAN_INTERCEPT(strcpy);  // NOLINT
    TSAN_INTERCEPT(strncpy);
    TSAN_INTERCEPT(strstr);
    TSAN_INTERCEPT(strdup);
  
    TSAN_INTERCEPT(pthread_create);
    TSAN_INTERCEPT(pthread_join);
    TSAN_INTERCEPT(pthread_detach);
  
    TSAN_INTERCEPT_VER(pthread_cond_init, "GLIBC_2.3.2");
    TSAN_INTERCEPT_VER(pthread_cond_signal, "GLIBC_2.3.2");
    TSAN_INTERCEPT_VER(pthread_cond_broadcast, "GLIBC_2.3.2");
    TSAN_INTERCEPT_VER(pthread_cond_wait, "GLIBC_2.3.2");
    TSAN_INTERCEPT_VER(pthread_cond_timedwait, "GLIBC_2.3.2");
    TSAN_INTERCEPT_VER(pthread_cond_destroy, "GLIBC_2.3.2");
  
    TSAN_INTERCEPT(pthread_mutex_init);
    TSAN_INTERCEPT(pthread_mutex_destroy);
    TSAN_INTERCEPT(pthread_mutex_trylock);
    TSAN_INTERCEPT(pthread_mutex_timedlock);
  
    TSAN_INTERCEPT(pthread_spin_init);
    TSAN_INTERCEPT(pthread_spin_destroy);
    TSAN_INTERCEPT(pthread_spin_lock);
    TSAN_INTERCEPT(pthread_spin_trylock);
    TSAN_INTERCEPT(pthread_spin_unlock);
  
    TSAN_INTERCEPT(pthread_rwlock_init);
    TSAN_INTERCEPT(pthread_rwlock_destroy);
    TSAN_INTERCEPT(pthread_rwlock_rdlock);
    TSAN_INTERCEPT(pthread_rwlock_tryrdlock);
    TSAN_INTERCEPT(pthread_rwlock_timedrdlock);
    TSAN_INTERCEPT(pthread_rwlock_wrlock);
    TSAN_INTERCEPT(pthread_rwlock_trywrlock);
    TSAN_INTERCEPT(pthread_rwlock_timedwrlock);
    TSAN_INTERCEPT(pthread_rwlock_unlock);
  
    TSAN_INTERCEPT(pthread_barrier_init);
    TSAN_INTERCEPT(pthread_barrier_destroy);
    TSAN_INTERCEPT(pthread_barrier_wait);
  
    TSAN_INTERCEPT(pthread_once);
  
    TSAN_INTERCEPT(sem_init);
    TSAN_INTERCEPT(sem_destroy);
    TSAN_INTERCEPT(sem_wait);
    TSAN_INTERCEPT(sem_trywait);
    TSAN_INTERCEPT(sem_timedwait);
    TSAN_INTERCEPT(sem_post);
    TSAN_INTERCEPT(sem_getvalue);
  
    TSAN_INTERCEPT(stat);
    TSAN_INTERCEPT(__xstat);
    TSAN_INTERCEPT(stat64);
    TSAN_INTERCEPT(__xstat64);
    TSAN_INTERCEPT(lstat);
    TSAN_INTERCEPT(__lxstat);
    TSAN_INTERCEPT(lstat64);
    TSAN_INTERCEPT(__lxstat64);
    TSAN_INTERCEPT(fstat);
    TSAN_INTERCEPT(__fxstat);
    TSAN_INTERCEPT(fstat64);
    TSAN_INTERCEPT(__fxstat64);
    TSAN_INTERCEPT(open);
    TSAN_INTERCEPT(open64);
    TSAN_INTERCEPT(creat);
    TSAN_INTERCEPT(creat64);
    TSAN_INTERCEPT(dup);
    TSAN_INTERCEPT(dup2);
    TSAN_INTERCEPT(dup3);
    TSAN_INTERCEPT(eventfd);
    TSAN_INTERCEPT(signalfd);
    TSAN_INTERCEPT(inotify_init);
    TSAN_INTERCEPT(inotify_init1);
    TSAN_INTERCEPT(socket);
    TSAN_INTERCEPT(socketpair);
    TSAN_INTERCEPT(connect);
    TSAN_INTERCEPT(bind);
    TSAN_INTERCEPT(listen);
    TSAN_INTERCEPT(epoll_create);
    TSAN_INTERCEPT(epoll_create1);
    TSAN_INTERCEPT(close);
    TSAN_INTERCEPT(__close);
    TSAN_INTERCEPT(__res_iclose);
    TSAN_INTERCEPT(pipe);
    TSAN_INTERCEPT(pipe2);
  
    TSAN_INTERCEPT(send);
    TSAN_INTERCEPT(sendmsg);
    TSAN_INTERCEPT(recv);
  
    TSAN_INTERCEPT(unlink);
    TSAN_INTERCEPT(tmpfile);
    TSAN_INTERCEPT(tmpfile64);
    TSAN_INTERCEPT(fread);
    TSAN_INTERCEPT(fwrite);
    TSAN_INTERCEPT(abort);
    TSAN_INTERCEPT(puts);
    TSAN_INTERCEPT(rmdir);
    TSAN_INTERCEPT(opendir);
  
    TSAN_INTERCEPT(epoll_ctl);
    TSAN_INTERCEPT(epoll_wait);
  
    TSAN_INTERCEPT(sigaction);
    TSAN_INTERCEPT(signal);
    TSAN_INTERCEPT(sigsuspend);
    TSAN_INTERCEPT(raise);
    TSAN_INTERCEPT(kill);
    TSAN_INTERCEPT(pthread_kill);
    TSAN_INTERCEPT(sleep);
    TSAN_INTERCEPT(usleep);
    TSAN_INTERCEPT(nanosleep);
    TSAN_INTERCEPT(gettimeofday);
    TSAN_INTERCEPT(getaddrinfo);
  
    TSAN_INTERCEPT(mlock);
    TSAN_INTERCEPT(munlock);
    TSAN_INTERCEPT(mlockall);
    TSAN_INTERCEPT(munlockall);
  
    TSAN_INTERCEPT(fork);
    TSAN_INTERCEPT(vfork);
    TSAN_INTERCEPT(on_exit);
    TSAN_INTERCEPT(__cxa_atexit);
    TSAN_INTERCEPT(_exit);
  
    // Need to setup it, because interceptors check that the function is resolved.
    // But atexit is emitted directly into the module, so can't be resolved.
    REAL(atexit) = (int(*)(void(*)()))unreachable;
    atexit_ctx = new(internal_alloc(MBlockAtExit, sizeof(AtExitContext)))
        AtExitContext();
  
    if (REAL(__cxa_atexit)(&finalize, 0, 0)) {
      Printf("ThreadSanitizer: failed to setup atexit callback\n");
      Die();
    }
  
    if (pthread_key_create(&g_thread_finalize_key, &thread_finalize)) {
      Printf("ThreadSanitizer: failed to create thread key\n");
      Die();
    }
  
    FdInit();
  }
  
  void *internal_start_thread(void(*func)(void *arg), void *arg) {
    // Start the thread with signals blocked, otherwise it can steal user signals.
    __sanitizer_sigset_t set, old;
    internal_sigfillset(&set);
    internal_sigprocmask(SIG_SETMASK, &set, &old);
    void *th;
    REAL(pthread_create)(&th, 0, (void*(*)(void *arg))func, arg);
    internal_sigprocmask(SIG_SETMASK, &old, 0);
    return th;
  }
  
  void internal_join_thread(void *th) {
    REAL(pthread_join)(th, 0);
  }
  
  }  // namespace __tsan
  