text: //===-- tsan_suppressions.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.
  //
  //===----------------------------------------------------------------------===//
  
  #include "sanitizer_common/sanitizer_common.h"
  #include "sanitizer_common/sanitizer_libc.h"
  #include "sanitizer_common/sanitizer_placement_new.h"
  #include "sanitizer_common/sanitizer_suppressions.h"
  #include "tsan_suppressions.h"
  #include "tsan_rtl.h"
  #include "tsan_flags.h"
  #include "tsan_mman.h"
  #include "tsan_platform.h"
  
  #if !SANITIZER_GO
  // Suppressions for true/false positives in standard libraries.
  static const char *const std_suppressions =
  // Libstdc++ 4.4 has data races in std::string.
  // See http://crbug.com/181502 for an example.
  "race:^_M_rep$\n"
  "race:^_M_is_leaked$\n"
  // False positive when using std <thread>.
  // Happens because we miss atomic synchronization in libstdc++.
  // See http://llvm.org/bugs/show_bug.cgi?id=17066 for details.
  "race:std::_Sp_counted_ptr_inplace<std::thread::_Impl\n";
  
  // Can be overriden in frontend.
  SANITIZER_WEAK_DEFAULT_IMPL
  const char *__tsan_default_suppressions() {
    return 0;
  }
  #endif
  
  namespace __tsan {
  
  ALIGNED(64) static char suppression_placeholder[sizeof(SuppressionContext)];
  static SuppressionContext *suppression_ctx = nullptr;
  static const char *kSuppressionTypes[] = {
      kSuppressionRace,   kSuppressionRaceTop, kSuppressionMutex,
      kSuppressionThread, kSuppressionSignal, kSuppressionLib,
      kSuppressionDeadlock};
  
  void InitializeSuppressions() {
    CHECK_EQ(nullptr, suppression_ctx);
    suppression_ctx = new (suppression_placeholder) // NOLINT
        SuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes));
    suppression_ctx->ParseFromFile(flags()->suppressions);
  #if !SANITIZER_GO
    suppression_ctx->Parse(__tsan_default_suppressions());
    suppression_ctx->Parse(std_suppressions);
  #endif
  }
  
  SuppressionContext *Suppressions() {
    CHECK(suppression_ctx);
    return suppression_ctx;
  }
  
  static const char *conv(ReportType typ) {
    if (typ == ReportTypeRace)
      return kSuppressionRace;
    else if (typ == ReportTypeVptrRace)
      return kSuppressionRace;
    else if (typ == ReportTypeUseAfterFree)
      return kSuppressionRace;
    else if (typ == ReportTypeVptrUseAfterFree)
      return kSuppressionRace;
    else if (typ == ReportTypeExternalRace)
      return kSuppressionRace;
    else if (typ == ReportTypeThreadLeak)
      return kSuppressionThread;
    else if (typ == ReportTypeMutexDestroyLocked)
      return kSuppressionMutex;
    else if (typ == ReportTypeMutexDoubleLock)
      return kSuppressionMutex;
    else if (typ == ReportTypeMutexInvalidAccess)
      return kSuppressionMutex;
    else if (typ == ReportTypeMutexBadUnlock)
      return kSuppressionMutex;
    else if (typ == ReportTypeMutexBadReadLock)
      return kSuppressionMutex;
    else if (typ == ReportTypeMutexBadReadUnlock)
      return kSuppressionMutex;
    else if (typ == ReportTypeSignalUnsafe)
      return kSuppressionSignal;
    else if (typ == ReportTypeErrnoInSignal)
      return kSuppressionNone;
    else if (typ == ReportTypeDeadlock)
      return kSuppressionDeadlock;
    Printf("ThreadSanitizer: unknown report type %d\n", typ);
    Die();
  }
  
  static uptr IsSuppressed(const char *stype, const AddressInfo &info,
      Suppression **sp) {
    if (suppression_ctx->Match(info.function, stype, sp) ||
        suppression_ctx->Match(info.file, stype, sp) ||
        suppression_ctx->Match(info.module, stype, sp)) {
      VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", (*sp)->templ);
      atomic_fetch_add(&(*sp)->hit_count, 1, memory_order_relaxed);
      return info.address;
    }
    return 0;
  }
  
  uptr IsSuppressed(ReportType typ, const ReportStack *stack, Suppression **sp) {
    CHECK(suppression_ctx);
    if (!suppression_ctx->SuppressionCount() || stack == 0 ||
        !stack->suppressable)
      return 0;
    const char *stype = conv(typ);
    if (0 == internal_strcmp(stype, kSuppressionNone))
      return 0;
    for (const SymbolizedStack *frame = stack->frames; frame;
        frame = frame->next) {
      uptr pc = IsSuppressed(stype, frame->info, sp);
      if (pc != 0)
        return pc;
    }
    if (0 == internal_strcmp(stype, kSuppressionRace) && stack->frames != nullptr)
      return IsSuppressed(kSuppressionRaceTop, stack->frames->info, sp);
    return 0;
  }
  
  uptr IsSuppressed(ReportType typ, const ReportLocation *loc, Suppression **sp) {
    CHECK(suppression_ctx);
    if (!suppression_ctx->SuppressionCount() || loc == 0 ||
        loc->type != ReportLocationGlobal || !loc->suppressable)
      return 0;
    const char *stype = conv(typ);
    if (0 == internal_strcmp(stype, kSuppressionNone))
      return 0;
    Suppression *s;
    const DataInfo &global = loc->global;
    if (suppression_ctx->Match(global.name, stype, &s) ||
        suppression_ctx->Match(global.module, stype, &s)) {
        VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", s->templ);
        atomic_fetch_add(&s->hit_count, 1, memory_order_relaxed);
        *sp = s;
        return global.start;
    }
    return 0;
  }
  
  void PrintMatchedSuppressions() {
    InternalMmapVector<Suppression *> matched;
    CHECK(suppression_ctx);
    suppression_ctx->GetMatched(&matched);
    if (!matched.size())
      return;
    int hit_count = 0;
    for (uptr i = 0; i < matched.size(); i++)
      hit_count += atomic_load_relaxed(&matched[i]->hit_count);
    Printf("ThreadSanitizer: Matched %d suppressions (pid=%d):\n", hit_count,
           (int)internal_getpid());
    for (uptr i = 0; i < matched.size(); i++) {
      Printf("%d %s:%s\n", atomic_load_relaxed(&matched[i]->hit_count),
             matched[i]->type, matched[i]->templ);
    }
  }
  }  // namespace __tsan
  