chromium/third_party/crashpad/crashpad/util/posix/signals.cc

// Copyright 2017 The Crashpad 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.

#include "util/posix/signals.h"

#include <unistd.h>

#include <iterator>
#include <vector>

#include "base/check_op.h"
#include "base/logging.h"
#include "build/build_config.h"

#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS)
#include <sys/syscall.h>
#endif

namespace crashpad {

namespace {

// These are the core-generating signals.
//
// On macOS, these come from 10.12.3 xnu-3789.41.3/bsd/sys/signalvar.h sigprop:
// entries with SA_CORE are in the set.
//
// For Linux, see linux-4.4.52/kernel/signal.c get_signal() and
// linux-4.4.52/include/linux/signal.h sig_kernel_coredump(): signals in
// SIG_KERNEL_COREDUMP_MASK are in the set.
constexpr int kCrashSignals[] = …;

// These are the non-core-generating but terminating signals.
//
// On macOS, these come from 10.12.3 xnu-3789.41.3/bsd/sys/signalvar.h sigprop:
// entries with SA_KILL but not SA_CORE are in the set. SIGKILL is excluded
// because it is uncatchable.
//
// For Linux, see linux-4.4.52/kernel/signal.c get_signal() and
// linux-4.4.52/include/linux/signal.h sig_kernel_coredump(),
// sig_kernel_ignore(), and sig_kernel_stop(): signals not in
// SIG_KERNEL_COREDUMP_MASK, SIG_KERNEL_IGNORE_MASK, or SIG_KERNEL_STOP_MASK are
// in the set. SIGKILL is excluded because it is uncatchable (it’s in
// SIG_KERNEL_ONLY_MASK and qualifies for sig_kernel_only()). Real-time signals
// in the range [SIGRTMIN, SIGRTMAX) also have termination as the default
// action, although they are not listed here.
constexpr int kTerminateSignals[] = …;

bool InstallHandlers(const std::vector<int>& signals,
                     Signals::Handler handler,
                     int flags,
                     Signals::OldActions* old_actions,
                     const std::set<int>* unhandled_signals) { … }

bool IsSignalInSet(int sig, const int* set, size_t set_size) { … }

}  // namespace

struct sigaction* Signals::OldActions::ActionForSignal(int sig) { … }

// static
bool Signals::InstallHandler(int sig,
                             Handler handler,
                             int flags,
                             struct sigaction* old_action) { … }

// static
bool Signals::InstallDefaultHandler(int sig) { … }

// static
bool Signals::InstallCrashHandlers(Handler handler,
                                   int flags,
                                   OldActions* old_actions,
                                   const std::set<int>* unhandled_signals) { … }

// static
bool Signals::InstallTerminateHandlers(Handler handler,
                                       int flags,
                                       OldActions* old_actions) { … }

// static
bool Signals::WillSignalReraiseAutonomously(const siginfo_t* siginfo) { … }

// static
void Signals::RestoreHandlerAndReraiseSignalOnReturn(
    const siginfo_t* siginfo,
    const struct sigaction* old_action) { … }

// static
bool Signals::IsCrashSignal(int sig) { … }

// static
bool Signals::IsTerminateSignal(int sig) { … }

}  // namespace crashpad