7454bdded7
- 83dbeb97cb3874932a4159f2f287c5b2cca7089b Fix for MSVC warning C4244 about "conversion from 'int' t... by Abseil Team <absl-team@google.com> GitOrigin-RevId: be60293bacf8d17861853a73c751b4a74534b049 Change-Id: If8a91fa3edca47f349662cb214fde380c65802bb
117 lines
5.3 KiB
C++
117 lines
5.3 KiB
C++
// 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
|
|
//
|
|
// http://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.
|
|
//
|
|
// -----------------------------------------------------------------------------
|
|
// File: failure_signal_handler.h
|
|
// -----------------------------------------------------------------------------
|
|
//
|
|
// This file configures the Abseil *failure signal handler* to capture and dump
|
|
// useful debugging information (such as a stacktrace) upon program failure.
|
|
//
|
|
// To use the failure signal handler, call `absl::InstallFailureSignalHandler()`
|
|
// very early in your program, usually in the first few lines of main():
|
|
//
|
|
// int main(int argc, char** argv) {
|
|
// // Initialize the symbolizer to get a human-readable stack trace
|
|
// absl::InitializeSymbolizer(argv[0]);
|
|
//
|
|
// absl::FailureSignalHandlerOptions options;
|
|
// absl::InstallFailureSignalHandler(options);
|
|
// DoSomethingInteresting();
|
|
// return 0;
|
|
// }
|
|
//
|
|
// Any program that raises a fatal signal (such as `SIGSEGV`, `SIGILL`,
|
|
// `SIGFPE`, `SIGABRT`, `SIGTERM`, `SIGBUG`, and `SIGTRAP`) will call the
|
|
// installed failure signal handler and provide debugging information to stderr.
|
|
//
|
|
// Note that you should *not* install the Abseil failure signal handler more
|
|
// than once. You may, of course, have another (non-Abseil) failure signal
|
|
// handler installed (which would be triggered if Abseil's failure signal
|
|
// handler sets `call_previous_handler` to `true`).
|
|
|
|
#ifndef ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
|
|
#define ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
|
|
|
|
namespace absl {
|
|
|
|
// FailureSignalHandlerOptions
|
|
//
|
|
// Struct for holding `absl::InstallFailureSignalHandler()` configuration
|
|
// options.
|
|
struct FailureSignalHandlerOptions {
|
|
// If true, try to symbolize the stacktrace emitted on failure, provided that
|
|
// you have initialized a symbolizer for that purpose. (See symbolize.h for
|
|
// more information.)
|
|
bool symbolize_stacktrace = true;
|
|
|
|
// If true, try to run signal handlers on an alternate stack (if supported on
|
|
// the given platform). An alternate stack is useful for program crashes due
|
|
// to a stack overflow; by running on a alternate stack, the signal handler
|
|
// may run even when normal stack space has been exausted. The downside of
|
|
// using an alternate stack is that extra memory for the alternate stack needs
|
|
// to be pre-allocated.
|
|
bool use_alternate_stack = true;
|
|
|
|
// If positive, indicates the number of seconds after which the failure signal
|
|
// handler is invoked to abort the program. Setting such an alarm is useful in
|
|
// cases where the failure signal handler itself may become hung or
|
|
// deadlocked.
|
|
int alarm_on_failure_secs = 3;
|
|
|
|
// If true, call the previously registered signal handler for the signal that
|
|
// was received (if one was registered) after the existing signal handler
|
|
// runs. This mechanism can be used to chain signal handlers together.
|
|
//
|
|
// If false, the signal is raised to the default handler for that signal
|
|
// (which normally terminates the program).
|
|
//
|
|
// IMPORTANT: If true, the chained fatal signal handlers must not try to
|
|
// recover from the fatal signal. Instead, they should terminate the program
|
|
// via some mechanism, like raising the default handler for the signal, or by
|
|
// calling `_exit()`. Note that the failure signal handler may put parts of
|
|
// the Abseil library into a state from which they cannot recover.
|
|
bool call_previous_handler = false;
|
|
|
|
// If non-null, indicates a pointer to a callback function that will be called
|
|
// upon failure, with a std::string argument containing failure data. This function
|
|
// may be used as a hook to write failure data to a secondary location, such
|
|
// as a log file. This function may also be called with null data, as a hint
|
|
// to flush any buffered data before the program may be terminated. Consider
|
|
// flushing any buffered data in all calls to this function.
|
|
//
|
|
// Since this function runs within a signal handler, it should be
|
|
// async-signal-safe if possible.
|
|
// See http://man7.org/linux/man-pages/man7/signal-safety.7.html
|
|
void (*writerfn)(const char*) = nullptr;
|
|
};
|
|
|
|
// InstallFailureSignalHandler()
|
|
//
|
|
// Installs a signal handler for the common failure signals `SIGSEGV`, `SIGILL`,
|
|
// `SIGFPE`, `SIGABRT`, `SIGTERM`, `SIGBUG`, and `SIGTRAP` (provided they exist
|
|
// on the given platform). The failure signal handler dumps program failure data
|
|
// useful for debugging in an unspecified format to stderr. This data may
|
|
// include the program counter, a stacktrace, and register information on some
|
|
// systems; do not rely on an exact format for the output, as it is subject to
|
|
// change.
|
|
void InstallFailureSignalHandler(const FailureSignalHandlerOptions& options);
|
|
|
|
namespace debugging_internal {
|
|
const char* FailureSignalToString(int signo);
|
|
} // namespace debugging_internal
|
|
|
|
} // namespace absl
|
|
|
|
#endif // ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
|