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Diffstat (limited to 'include/llvm/Support/CrashRecoveryContext.h')
-rw-r--r-- | include/llvm/Support/CrashRecoveryContext.h | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/include/llvm/Support/CrashRecoveryContext.h b/include/llvm/Support/CrashRecoveryContext.h new file mode 100644 index 000000000000..d66609fddfec --- /dev/null +++ b/include/llvm/Support/CrashRecoveryContext.h @@ -0,0 +1,84 @@ +//===--- CrashRecoveryContext.h - Crash Recovery ----------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_SUPPORT_CRASHRECOVERYCONTEXT_H +#define LLVM_SUPPORT_CRASHRECOVERYCONTEXT_H + +#include <string> + +namespace llvm { +class StringRef; + +/// \brief Crash recovery helper object. +/// +/// This class implements support for running operations in a safe context so +/// that crashes (memory errors, stack overflow, assertion violations) can be +/// detected and control restored to the crashing thread. Crash detection is +/// purely "best effort", the exact set of failures which can be recovered from +/// is platform dependent. +/// +/// Clients make use of this code by first calling +/// CrashRecoveryContext::Enable(), and then executing unsafe operations via a +/// CrashRecoveryContext object. For example: +/// +/// void actual_work(void *); +/// +/// void foo() { +/// CrashRecoveryContext CRC; +/// +/// if (!CRC.RunSafely(actual_work, 0)) { +/// ... a crash was detected, report error to user ... +/// } +/// +/// ... no crash was detected ... +/// } +/// +/// Crash recovery contexts may not be nested. +class CrashRecoveryContext { + void *Impl; + +public: + CrashRecoveryContext() : Impl(0) {} + ~CrashRecoveryContext(); + + /// \brief Enable crash recovery. + static void Enable(); + + /// \brief Disable crash recovery. + static void Disable(); + + /// \brief Return the active context, if the code is currently executing in a + /// thread which is in a protected context. + static CrashRecoveryContext *GetCurrent(); + + /// \brief Execute the provide callback function (with the given arguments) in + /// a protected context. + /// + /// \return True if the function completed successfully, and false if the + /// function crashed (or HandleCrash was called explicitly). Clients should + /// make as little assumptions as possible about the program state when + /// RunSafely has returned false. Clients can use getBacktrace() to retrieve + /// the backtrace of the crash on failures. + bool RunSafely(void (*Fn)(void*), void *UserData); + + /// \brief Explicitly trigger a crash recovery in the current process, and + /// return failure from RunSafely(). This function does not return. + void HandleCrash(); + + /// \brief Return a string containing the backtrace where the crash was + /// detected; or empty if the backtrace wasn't recovered. + /// + /// This function is only valid when a crash has been detected (i.e., + /// RunSafely() has returned false. + const std::string &getBacktrace() const; +}; + +} + +#endif |