1//===--- ThreadCrashReporter.h - Thread local signal handling ----*- 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#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_THREADCRASHREPORTER_H
10#define LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_THREADCRASHREPORTER_H
11
12#include "llvm/ADT/FunctionExtras.h"
13
14namespace clang {
15namespace clangd {
16
17/// Allows setting per-thread abort/kill signal callbacks, to print additional
18/// information about the crash depending on which thread got signalled.
19class ThreadCrashReporter {
20public:
21 using SignalCallback = llvm::unique_function<void(void)>;
22
23 /// Registers the callback as the first one in thread-local callback chain.
24 ///
25 /// Asserts if the current thread's callback is already set. The callback is
26 /// likely to be invoked in a signal handler. Most LLVM signal handling is not
27 /// strictly async-signal-safe. However reporters should avoid accessing data
28 /// structures likely to be in a bad state on crash.
29 ThreadCrashReporter(SignalCallback ThreadLocalCallback);
30 /// Resets the current thread's callback to nullptr.
31 ~ThreadCrashReporter();
32
33 /// Moves are disabled to ease nesting and escaping considerations.
34 ThreadCrashReporter(ThreadCrashReporter &&RHS) = delete;
35 ThreadCrashReporter(const ThreadCrashReporter &) = delete;
36 ThreadCrashReporter &operator=(ThreadCrashReporter &&) = delete;
37 ThreadCrashReporter &operator=(const ThreadCrashReporter &) = delete;
38
39 /// Calls all currently-active ThreadCrashReporters for the current thread.
40 ///
41 /// To be called from sys::AddSignalHandler() callback. Any signal filtering
42 /// is the responsibility of the caller. While this function is intended to be
43 /// called from signal handlers, it is not strictly async-signal-safe - see
44 /// constructor comment.
45 ///
46 /// When several reporters are nested, the callbacks are called in LIFO order.
47 static void runCrashHandlers();
48
49private:
50 SignalCallback Callback;
51 /// Points to the next reporter up the stack.
52 ThreadCrashReporter *Next;
53};
54
55} // namespace clangd
56} // namespace clang
57
58#endif
59

source code of clang-tools-extra/clangd/support/ThreadCrashReporter.h