1//===- llvm/Support/Signals.h - Signal Handling support ----------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines some helpful functions for dealing with the possibility of
10// unix signals occurring while your program is running.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_SIGNALS_H
15#define LLVM_SUPPORT_SIGNALS_H
16
17#include <cstdint>
18#include <string>
19
20namespace llvm {
21class StringRef;
22class raw_ostream;
23
24namespace sys {
25
26 /// This function runs all the registered interrupt handlers, including the
27 /// removal of files registered by RemoveFileOnSignal.
28 void RunInterruptHandlers();
29
30 /// This function registers signal handlers to ensure that if a signal gets
31 /// delivered that the named file is removed.
32 /// Remove a file if a fatal signal occurs.
33 bool RemoveFileOnSignal(StringRef Filename, std::string* ErrMsg = nullptr);
34
35 /// This function removes a file from the list of files to be removed on
36 /// signal delivery.
37 void DontRemoveFileOnSignal(StringRef Filename);
38
39 /// When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
40 /// process, print a stack trace and then exit.
41 /// Print a stack trace if a fatal signal occurs.
42 /// \param Argv0 the current binary name, used to find the symbolizer
43 /// relative to the current binary before searching $PATH; can be
44 /// StringRef(), in which case we will only search $PATH.
45 /// \param DisableCrashReporting if \c true, disable the normal crash
46 /// reporting mechanisms on the underlying operating system.
47 void PrintStackTraceOnErrorSignal(StringRef Argv0,
48 bool DisableCrashReporting = false);
49
50 /// Disable all system dialog boxes that appear when the process crashes.
51 void DisableSystemDialogsOnCrash();
52
53 /// Print the stack trace using the given \c raw_ostream object.
54 /// \param Depth refers to the number of stackframes to print. If not
55 /// specified, the entire frame is printed.
56 void PrintStackTrace(raw_ostream &OS, int Depth = 0);
57
58 // Run all registered signal handlers.
59 void RunSignalHandlers();
60
61 using SignalHandlerCallback = void (*)(void *);
62
63 /// Add a function to be called when an abort/kill signal is delivered to the
64 /// process. The handler can have a cookie passed to it to identify what
65 /// instance of the handler it is.
66 void AddSignalHandler(SignalHandlerCallback FnPtr, void *Cookie);
67
68 /// This function registers a function to be called when the user "interrupts"
69 /// the program (typically by pressing ctrl-c). When the user interrupts the
70 /// program, the specified interrupt function is called instead of the program
71 /// being killed, and the interrupt function automatically disabled.
72 ///
73 /// Note that interrupt functions are not allowed to call any non-reentrant
74 /// functions. An null interrupt function pointer disables the current
75 /// installed function. Note also that the handler may be executed on a
76 /// different thread on some platforms.
77 void SetInterruptFunction(void (*IF)());
78
79 /// Registers a function to be called when an "info" signal is delivered to
80 /// the process.
81 ///
82 /// On POSIX systems, this will be SIGUSR1; on systems that have it, SIGINFO
83 /// will also be used (typically ctrl-t).
84 ///
85 /// Note that signal handlers are not allowed to call any non-reentrant
86 /// functions. An null function pointer disables the current installed
87 /// function. Note also that the handler may be executed on a different
88 /// thread on some platforms.
89 void SetInfoSignalFunction(void (*Handler)());
90
91 /// Registers a function to be called in a "one-shot" manner when a pipe
92 /// signal is delivered to the process (i.e., on a failed write to a pipe).
93 /// After the pipe signal is handled once, the handler is unregistered.
94 ///
95 /// The LLVM signal handling code will not install any handler for the pipe
96 /// signal unless one is provided with this API (see \ref
97 /// DefaultOneShotPipeSignalHandler). This handler must be provided before
98 /// any other LLVM signal handlers are installed: the \ref InitLLVM
99 /// constructor has a flag that can simplify this setup.
100 ///
101 /// Note that the handler is not allowed to call any non-reentrant
102 /// functions. A null handler pointer disables the current installed
103 /// function. Note also that the handler may be executed on a
104 /// different thread on some platforms.
105 ///
106 /// This is a no-op on Windows.
107 void SetOneShotPipeSignalFunction(void (*Handler)());
108
109 /// On Unix systems, this function exits with an "IO error" exit code.
110 /// This is a no-op on Windows.
111 void DefaultOneShotPipeSignalHandler();
112
113 /// This function does the following:
114 /// - clean up any temporary files registered with RemoveFileOnSignal()
115 /// - dump the callstack from the exception context
116 /// - call any relevant interrupt/signal handlers
117 /// - create a core/mini dump of the exception context whenever possible
118 /// Context is a system-specific failure context: it is the signal type on
119 /// Unix; the ExceptionContext on Windows.
120 void CleanupOnSignal(uintptr_t Context);
121
122 void unregisterHandlers();
123} // End sys namespace
124} // End llvm namespace
125
126#endif
127

source code of llvm/include/llvm/Support/Signals.h