llvm::CrashRecoveryContext Class Reference

Crash recovery helper object. More...

#include <CrashRecoveryContext.h>

List of all members.

Public Member Functions
	CrashRecoveryContext ()
	~CrashRecoveryContext ()
void	registerCleanup (CrashRecoveryContextCleanup *cleanup)
void	unregisterCleanup (CrashRecoveryContextCleanup *cleanup)
bool	RunSafely (void(*Fn)(void *), void *UserData)
	Execute the provide callback function (with the given arguments) in a protected context.
bool	RunSafelyOnThread (void(*Fn)(void *), void *UserData, unsigned RequestedStackSize=0)
	Execute the provide callback function (with the given arguments) in a protected context which is run in another thread (optionally with a requested stack size).
void	HandleCrash ()
	Explicitly trigger a crash recovery in the current process, and return failure from RunSafely(). This function does not return.
const std::string &	getBacktrace () const
	Return a string containing the backtrace where the crash was detected; or empty if the backtrace wasn't recovered.
Static Public Member Functions
static void	Enable ()
	Enable crash recovery.
static void	Disable ()
	Disable crash recovery.
static CrashRecoveryContext *	GetCurrent ()
	Return the active context, if the code is currently executing in a thread which is in a protected context.
static bool	isRecoveringFromCrash ()
	Return true if the current thread is recovering from a crash.

---

Detailed Description

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.

Definition at line 45 of file CrashRecoveryContext.h.

---

Constructor & Destructor Documentation

llvm::CrashRecoveryContext::CrashRecoveryContext

(

)

[inline]

Definition at line 50 of file CrashRecoveryContext.h.

CrashRecoveryContext::~CrashRecoveryContext

(

)

Definition at line 66 of file CrashRecoveryContext.cpp.

References llvm::CrashRecoveryContextCleanup::cleanupFired, llvm::CrashRecoveryContextCleanup::recoverResources(), and tlIsRecoveringFromCrash.

---

Member Function Documentation

void CrashRecoveryContext::Disable

(

)

[static]

Disable crash recovery.

Definition at line 281 of file CrashRecoveryContext.cpp.

References gCrashRecoveryContexMutex, gCrashRecoveryEnabled, NumSignals, PrevActions, and Signals.

Referenced by CrashRecoverySignalHandler().

void CrashRecoveryContext::Enable

(

)

[static]

Enable crash recovery.

Definition at line 262 of file CrashRecoveryContext.cpp.

References CrashRecoverySignalHandler(), gCrashRecoveryContexMutex, gCrashRecoveryEnabled, NumSignals, PrevActions, and Signals.

const std::string & CrashRecoveryContext::getBacktrace

(

)

const

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.

Definition at line 318 of file CrashRecoveryContext.cpp.

CrashRecoveryContext * CrashRecoveryContext::GetCurrent

(

)

[static]

Return the active context, if the code is currently executing in a thread which is in a protected context.

Definition at line 87 of file CrashRecoveryContext.cpp.

References gCrashRecoveryEnabled, and llvm::sys::ThreadLocal< T >::get().

Referenced by llvm::CrashRecoveryContextCleanupBase< CrashRecoveryContextDestructorCleanup< T >, T >::create().

void CrashRecoveryContext::HandleCrash

(

)

Explicitly trigger a crash recovery in the current process, and return failure from RunSafely(). This function does not return.

Definition at line 312 of file CrashRecoveryContext.cpp.

bool CrashRecoveryContext::isRecoveringFromCrash

(

)

[static]

Return true if the current thread is recovering from a crash.

Definition at line 83 of file CrashRecoveryContext.cpp.

References tlIsRecoveringFromCrash.

void CrashRecoveryContext::registerCleanup

(

CrashRecoveryContextCleanup *

cleanup

)

Definition at line 98 of file CrashRecoveryContext.cpp.

Referenced by llvm::CrashRecoveryContextCleanupRegistrar< T, Cleanup >::CrashRecoveryContextCleanupRegistrar().

bool CrashRecoveryContext::RunSafely	(	void(*)(void *)	Fn,
		void *	UserData
	)

Execute the provide callback function (with the given arguments) in a protected context.

Returns:

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.

Definition at line 296 of file CrashRecoveryContext.cpp.

References gCrashRecoveryEnabled.

bool CrashRecoveryContext::RunSafelyOnThread	(	void(*)(void *)	Fn,
		void *	UserData,
		unsigned	RequestedStackSize = 0
	)

Execute the provide callback function (with the given arguments) in a protected context which is run in another thread (optionally with a requested stack size).

See RunSafely() and llvm_execute_on_thread().

Definition at line 341 of file CrashRecoveryContext.cpp.

References llvm::llvm_execute_on_thread(), and RunSafelyOnThread_Dispatch().

void CrashRecoveryContext::unregisterCleanup

(

CrashRecoveryContextCleanup *

cleanup

)

Definition at line 109 of file CrashRecoveryContext.cpp.

Referenced by llvm::CrashRecoveryContextCleanupRegistrar< T, Cleanup >::unregister().

---

The documentation for this class was generated from the following files:

• CrashRecoveryContext.h
• CrashRecoveryContext.cpp