//===- llvm/Support/Signals.h - Signal Handling support ----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines some helpful functions for dealing with the possibility of
// unix signals occurring while your program is running.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_SIGNALS_H
#define LLVM_SUPPORT_SIGNALS_H
#include <string>
namespace llvm {
class StringRef;
class raw_ostream;
namespace sys {
/// This function runs all the registered interrupt handlers, including the
/// removal of files registered by RemoveFileOnSignal.
void RunInterruptHandlers();
/// This function registers signal handlers to ensure that if a signal gets
/// delivered that the named file is removed.
/// Remove a file if a fatal signal occurs.
bool RemoveFileOnSignal(StringRef Filename, std::string* ErrMsg = nullptr);
/// This function removes a file from the list of files to be removed on
/// signal delivery.
void DontRemoveFileOnSignal(StringRef Filename);
/// When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
/// process, print a stack trace and then exit.
/// Print a stack trace if a fatal signal occurs.
/// \param Argv0 the current binary name, used to find the symbolizer
/// relative to the current binary before searching $PATH; can be
/// StringRef(), in which case we will only search $PATH.
/// \param DisableCrashReporting if \c true, disable the normal crash
/// reporting mechanisms on the underlying operating system.
void PrintStackTraceOnErrorSignal(StringRef Argv0,
bool DisableCrashReporting = false);
/// Disable all system dialog boxes that appear when the process crashes.
void DisableSystemDialogsOnCrash();
/// Print the stack trace using the given \c raw_ostream object.
void PrintStackTrace(raw_ostream &OS);
// Run all registered signal handlers.
void RunSignalHandlers();
using SignalHandlerCallback = void (*)(void *);
/// Add a function to be called when an abort/kill signal is delivered to the
/// process. The handler can have a cookie passed to it to identify what
/// instance of the handler it is.
void AddSignalHandler(SignalHandlerCallback FnPtr, void *Cookie);
/// This function registers a function to be called when the user "interrupts"
/// the program (typically by pressing ctrl-c). When the user interrupts the
/// program, the specified interrupt function is called instead of the program
/// being killed, and the interrupt function automatically disabled.
///
/// Note that interrupt functions are not allowed to call any non-reentrant
/// functions. An null interrupt function pointer disables the current
/// installed function. Note also that the handler may be executed on a
/// different thread on some platforms.
void SetInterruptFunction(void (*IF)());
/// Registers a function to be called when an "info" signal is delivered to
/// the process.
///
/// On POSIX systems, this will be SIGUSR1; on systems that have it, SIGINFO
/// will also be used (typically ctrl-t).
///
/// Note that signal handlers are not allowed to call any non-reentrant
/// functions. An null function pointer disables the current installed
/// function. Note also that the handler may be executed on a different
/// thread on some platforms.
void SetInfoSignalFunction(void (*Handler)());
/// Registers a function to be called in a "one-shot" manner when a pipe
/// signal is delivered to the process (i.e., on a failed write to a pipe).
/// After the pipe signal is handled once, the handler is unregistered.
///
/// The LLVM signal handling code will not install any handler for the pipe
/// signal unless one is provided with this API (see \ref
/// DefaultOneShotPipeSignalHandler). This handler must be provided before
/// any other LLVM signal handlers are installed: the \ref InitLLVM
/// constructor has a flag that can simplify this setup.
///
/// Note that the handler is not allowed to call any non-reentrant
/// functions. A null handler pointer disables the current installed
/// function. Note also that the handler may be executed on a
/// different thread on some platforms.
///
/// This is a no-op on Windows.
void SetOneShotPipeSignalFunction(void (*Handler)());
/// On Unix systems, this function exits with an "IO error" exit code.
/// This is a no-op on Windows.
void DefaultOneShotPipeSignalHandler();
/// This function does the following:
/// - clean up any temporary files registered with RemoveFileOnSignal()
/// - dump the callstack from the exception context
/// - call any relevant interrupt/signal handlers
/// - create a core/mini dump of the exception context whenever possible
/// Context is a system-specific failure context: it is the signal type on
/// Unix; the ExceptionContext on Windows.
void CleanupOnSignal(uintptr_t Context);
} // End sys namespace
} // End llvm namespace
#endif