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Diffstat (limited to 'third_party/abseil_cpp/absl/debugging/failure_signal_handler.cc')
-rw-r--r--third_party/abseil_cpp/absl/debugging/failure_signal_handler.cc370
1 files changed, 0 insertions, 370 deletions
diff --git a/third_party/abseil_cpp/absl/debugging/failure_signal_handler.cc b/third_party/abseil_cpp/absl/debugging/failure_signal_handler.cc
deleted file mode 100644
index 1f69bfa84d..0000000000
--- a/third_party/abseil_cpp/absl/debugging/failure_signal_handler.cc
+++ /dev/null
@@ -1,370 +0,0 @@
-//
-// Copyright 2018 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-
-#include "absl/debugging/failure_signal_handler.h"
-
-#include "absl/base/config.h"
-
-#ifdef _WIN32
-#include <windows.h>
-#else
-#include <unistd.h>
-#endif
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif
-
-#ifdef ABSL_HAVE_MMAP
-#include <sys/mman.h>
-#endif
-
-#include <algorithm>
-#include <atomic>
-#include <cerrno>
-#include <csignal>
-#include <cstdio>
-#include <cstring>
-#include <ctime>
-
-#include "absl/base/attributes.h"
-#include "absl/base/internal/errno_saver.h"
-#include "absl/base/internal/raw_logging.h"
-#include "absl/base/internal/sysinfo.h"
-#include "absl/debugging/internal/examine_stack.h"
-#include "absl/debugging/stacktrace.h"
-
-#ifndef _WIN32
-#define ABSL_HAVE_SIGACTION
-// Apple WatchOS and TVOS don't allow sigaltstack
-#if !(defined(TARGET_OS_WATCH) && TARGET_OS_WATCH) && \
-    !(defined(TARGET_OS_TV) && TARGET_OS_TV)
-#define ABSL_HAVE_SIGALTSTACK
-#endif
-#endif
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-
-ABSL_CONST_INIT static FailureSignalHandlerOptions fsh_options;
-
-// Resets the signal handler for signo to the default action for that
-// signal, then raises the signal.
-static void RaiseToDefaultHandler(int signo) {
-  signal(signo, SIG_DFL);
-  raise(signo);
-}
-
-struct FailureSignalData {
-  const int signo;
-  const char* const as_string;
-#ifdef ABSL_HAVE_SIGACTION
-  struct sigaction previous_action;
-  // StructSigaction is used to silence -Wmissing-field-initializers.
-  using StructSigaction = struct sigaction;
-  #define FSD_PREVIOUS_INIT FailureSignalData::StructSigaction()
-#else
-  void (*previous_handler)(int);
-  #define FSD_PREVIOUS_INIT SIG_DFL
-#endif
-};
-
-ABSL_CONST_INIT static FailureSignalData failure_signal_data[] = {
-    {SIGSEGV, "SIGSEGV", FSD_PREVIOUS_INIT},
-    {SIGILL, "SIGILL", FSD_PREVIOUS_INIT},
-    {SIGFPE, "SIGFPE", FSD_PREVIOUS_INIT},
-    {SIGABRT, "SIGABRT", FSD_PREVIOUS_INIT},
-    {SIGTERM, "SIGTERM", FSD_PREVIOUS_INIT},
-#ifndef _WIN32
-    {SIGBUS, "SIGBUS", FSD_PREVIOUS_INIT},
-    {SIGTRAP, "SIGTRAP", FSD_PREVIOUS_INIT},
-#endif
-};
-
-#undef FSD_PREVIOUS_INIT
-
-static void RaiseToPreviousHandler(int signo) {
-  // Search for the previous handler.
-  for (const auto& it : failure_signal_data) {
-    if (it.signo == signo) {
-#ifdef ABSL_HAVE_SIGACTION
-      sigaction(signo, &it.previous_action, nullptr);
-#else
-      signal(signo, it.previous_handler);
-#endif
-      raise(signo);
-      return;
-    }
-  }
-
-  // Not found, use the default handler.
-  RaiseToDefaultHandler(signo);
-}
-
-namespace debugging_internal {
-
-const char* FailureSignalToString(int signo) {
-  for (const auto& it : failure_signal_data) {
-    if (it.signo == signo) {
-      return it.as_string;
-    }
-  }
-  return "";
-}
-
-}  // namespace debugging_internal
-
-#ifdef ABSL_HAVE_SIGALTSTACK
-
-static bool SetupAlternateStackOnce() {
-#if defined(__wasm__) || defined (__asjms__)
-  const size_t page_mask = getpagesize() - 1;
-#else
-  const size_t page_mask = sysconf(_SC_PAGESIZE) - 1;
-#endif
-  size_t stack_size = (std::max(SIGSTKSZ, 65536) + page_mask) & ~page_mask;
-#if defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER) || \
-    defined(THREAD_SANITIZER)
-  // Account for sanitizer instrumentation requiring additional stack space.
-  stack_size *= 5;
-#endif
-
-  stack_t sigstk;
-  memset(&sigstk, 0, sizeof(sigstk));
-  sigstk.ss_size = stack_size;
-
-#ifdef ABSL_HAVE_MMAP
-#ifndef MAP_STACK
-#define MAP_STACK 0
-#endif
-#if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
-#define MAP_ANONYMOUS MAP_ANON
-#endif
-  sigstk.ss_sp = mmap(nullptr, sigstk.ss_size, PROT_READ | PROT_WRITE,
-                      MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
-  if (sigstk.ss_sp == MAP_FAILED) {
-    ABSL_RAW_LOG(FATAL, "mmap() for alternate signal stack failed");
-  }
-#else
-  sigstk.ss_sp = malloc(sigstk.ss_size);
-  if (sigstk.ss_sp == nullptr) {
-    ABSL_RAW_LOG(FATAL, "malloc() for alternate signal stack failed");
-  }
-#endif
-
-  if (sigaltstack(&sigstk, nullptr) != 0) {
-    ABSL_RAW_LOG(FATAL, "sigaltstack() failed with errno=%d", errno);
-  }
-  return true;
-}
-
-#endif
-
-#ifdef ABSL_HAVE_SIGACTION
-
-// Sets up an alternate stack for signal handlers once.
-// Returns the appropriate flag for sig_action.sa_flags
-// if the system supports using an alternate stack.
-static int MaybeSetupAlternateStack() {
-#ifdef ABSL_HAVE_SIGALTSTACK
-  ABSL_ATTRIBUTE_UNUSED static const bool kOnce = SetupAlternateStackOnce();
-  return SA_ONSTACK;
-#else
-  return 0;
-#endif
-}
-
-static void InstallOneFailureHandler(FailureSignalData* data,
-                                     void (*handler)(int, siginfo_t*, void*)) {
-  struct sigaction act;
-  memset(&act, 0, sizeof(act));
-  sigemptyset(&act.sa_mask);
-  act.sa_flags |= SA_SIGINFO;
-  // SA_NODEFER is required to handle SIGABRT from
-  // ImmediateAbortSignalHandler().
-  act.sa_flags |= SA_NODEFER;
-  if (fsh_options.use_alternate_stack) {
-    act.sa_flags |= MaybeSetupAlternateStack();
-  }
-  act.sa_sigaction = handler;
-  ABSL_RAW_CHECK(sigaction(data->signo, &act, &data->previous_action) == 0,
-                 "sigaction() failed");
-}
-
-#else
-
-static void InstallOneFailureHandler(FailureSignalData* data,
-                                     void (*handler)(int)) {
-  data->previous_handler = signal(data->signo, handler);
-  ABSL_RAW_CHECK(data->previous_handler != SIG_ERR, "signal() failed");
-}
-
-#endif
-
-static void WriteToStderr(const char* data) {
-  absl::base_internal::ErrnoSaver errno_saver;
-  absl::raw_logging_internal::SafeWriteToStderr(data, strlen(data));
-}
-
-static void WriteSignalMessage(int signo, void (*writerfn)(const char*)) {
-  char buf[64];
-  const char* const signal_string =
-      debugging_internal::FailureSignalToString(signo);
-  if (signal_string != nullptr && signal_string[0] != '\0') {
-    snprintf(buf, sizeof(buf), "*** %s received at time=%ld ***\n",
-             signal_string,
-             static_cast<long>(time(nullptr)));  // NOLINT(runtime/int)
-  } else {
-    snprintf(buf, sizeof(buf), "*** Signal %d received at time=%ld ***\n",
-             signo, static_cast<long>(time(nullptr)));  // NOLINT(runtime/int)
-  }
-  writerfn(buf);
-}
-
-// `void*` might not be big enough to store `void(*)(const char*)`.
-struct WriterFnStruct {
-  void (*writerfn)(const char*);
-};
-
-// Many of the absl::debugging_internal::Dump* functions in
-// examine_stack.h take a writer function pointer that has a void* arg
-// for historical reasons. failure_signal_handler_writer only takes a
-// data pointer. This function converts between these types.
-static void WriterFnWrapper(const char* data, void* arg) {
-  static_cast<WriterFnStruct*>(arg)->writerfn(data);
-}
-
-// Convenient wrapper around DumpPCAndFrameSizesAndStackTrace() for signal
-// handlers. "noinline" so that GetStackFrames() skips the top-most stack
-// frame for this function.
-ABSL_ATTRIBUTE_NOINLINE static void WriteStackTrace(
-    void* ucontext, bool symbolize_stacktrace,
-    void (*writerfn)(const char*, void*), void* writerfn_arg) {
-  constexpr int kNumStackFrames = 32;
-  void* stack[kNumStackFrames];
-  int frame_sizes[kNumStackFrames];
-  int min_dropped_frames;
-  int depth = absl::GetStackFramesWithContext(
-      stack, frame_sizes, kNumStackFrames,
-      1,  // Do not include this function in stack trace.
-      ucontext, &min_dropped_frames);
-  absl::debugging_internal::DumpPCAndFrameSizesAndStackTrace(
-      absl::debugging_internal::GetProgramCounter(ucontext), stack, frame_sizes,
-      depth, min_dropped_frames, symbolize_stacktrace, writerfn, writerfn_arg);
-}
-
-// Called by AbslFailureSignalHandler() to write the failure info. It is
-// called once with writerfn set to WriteToStderr() and then possibly
-// with writerfn set to the user provided function.
-static void WriteFailureInfo(int signo, void* ucontext,
-                             void (*writerfn)(const char*)) {
-  WriterFnStruct writerfn_struct{writerfn};
-  WriteSignalMessage(signo, writerfn);
-  WriteStackTrace(ucontext, fsh_options.symbolize_stacktrace, WriterFnWrapper,
-                  &writerfn_struct);
-}
-
-// absl::SleepFor() can't be used here since AbslInternalSleepFor()
-// may be overridden to do something that isn't async-signal-safe on
-// some platforms.
-static void PortableSleepForSeconds(int seconds) {
-#ifdef _WIN32
-  Sleep(seconds * 1000);
-#else
-  struct timespec sleep_time;
-  sleep_time.tv_sec = seconds;
-  sleep_time.tv_nsec = 0;
-  while (nanosleep(&sleep_time, &sleep_time) != 0 && errno == EINTR) {}
-#endif
-}
-
-#ifdef ABSL_HAVE_ALARM
-// AbslFailureSignalHandler() installs this as a signal handler for
-// SIGALRM, then sets an alarm to be delivered to the program after a
-// set amount of time. If AbslFailureSignalHandler() hangs for more than
-// the alarm timeout, ImmediateAbortSignalHandler() will abort the
-// program.
-static void ImmediateAbortSignalHandler(int) {
-  RaiseToDefaultHandler(SIGABRT);
-}
-#endif
-
-// absl::base_internal::GetTID() returns pid_t on most platforms, but
-// returns absl::base_internal::pid_t on Windows.
-using GetTidType = decltype(absl::base_internal::GetTID());
-ABSL_CONST_INIT static std::atomic<GetTidType> failed_tid(0);
-
-#ifndef ABSL_HAVE_SIGACTION
-static void AbslFailureSignalHandler(int signo) {
-  void* ucontext = nullptr;
-#else
-static void AbslFailureSignalHandler(int signo, siginfo_t*, void* ucontext) {
-#endif
-
-  const GetTidType this_tid = absl::base_internal::GetTID();
-  GetTidType previous_failed_tid = 0;
-  if (!failed_tid.compare_exchange_strong(
-          previous_failed_tid, static_cast<intptr_t>(this_tid),
-          std::memory_order_acq_rel, std::memory_order_relaxed)) {
-    ABSL_RAW_LOG(
-        ERROR,
-        "Signal %d raised at PC=%p while already in AbslFailureSignalHandler()",
-        signo, absl::debugging_internal::GetProgramCounter(ucontext));
-    if (this_tid != previous_failed_tid) {
-      // Another thread is already in AbslFailureSignalHandler(), so wait
-      // a bit for it to finish. If the other thread doesn't kill us,
-      // we do so after sleeping.
-      PortableSleepForSeconds(3);
-      RaiseToDefaultHandler(signo);
-      // The recursively raised signal may be blocked until we return.
-      return;
-    }
-  }
-
-#ifdef ABSL_HAVE_ALARM
-  // Set an alarm to abort the program in case this code hangs or deadlocks.
-  if (fsh_options.alarm_on_failure_secs > 0) {
-    alarm(0);  // Cancel any existing alarms.
-    signal(SIGALRM, ImmediateAbortSignalHandler);
-    alarm(fsh_options.alarm_on_failure_secs);
-  }
-#endif
-
-  // First write to stderr.
-  WriteFailureInfo(signo, ucontext, WriteToStderr);
-
-  // Riskier code (because it is less likely to be async-signal-safe)
-  // goes after this point.
-  if (fsh_options.writerfn != nullptr) {
-    WriteFailureInfo(signo, ucontext, fsh_options.writerfn);
-  }
-
-  if (fsh_options.call_previous_handler) {
-    RaiseToPreviousHandler(signo);
-  } else {
-    RaiseToDefaultHandler(signo);
-  }
-}
-
-void InstallFailureSignalHandler(const FailureSignalHandlerOptions& options) {
-  fsh_options = options;
-  for (auto& it : failure_signal_data) {
-    InstallOneFailureHandler(&it, AbslFailureSignalHandler);
-  }
-}
-
-ABSL_NAMESPACE_END
-}  // namespace absl