gecko-dev/xpcom/build/LateWriteChecks.h
2020-02-21 18:51:37 +00:00

79 lines
2.7 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_LateWriteChecks_h
#define mozilla_LateWriteChecks_h
// This file, along with LateWriteChecks.cpp, serves to check for and report
// late writes. The idea is discover writes to the file system that happens
// during shutdown such that these maybe be moved forward and the process may be
// killed without waiting for static destructors.
namespace mozilla {
/** Different shutdown check modes */
enum ShutdownChecksMode {
SCM_CRASH, /** Crash on shutdown check failure */
SCM_RECORD, /** Record shutdown check violations */
SCM_NOTHING /** Don't attempt any shutdown checks */
};
/**
* Current shutdown check mode.
* This variable is defined and initialized in nsAppRunner.cpp
*/
extern ShutdownChecksMode gShutdownChecks;
/**
* Allocate structures and acquire information from XPCOM necessary to do late
* write checks. This function must be invoked before BeginLateWriteChecks()
* and before XPCOM has stopped working.
*/
void InitLateWriteChecks();
/**
* Begin recording all writes as late-writes. This function should be called
* when all legitimate writes have occurred. This function does not rely on
* XPCOM as it is designed to be invoked during XPCOM shutdown.
*
* For late-write checks to work you must initialize one or more backends that
* reports IO through the IOInterposer API. PoisonIOInterposer would probably
* be the backend of choice in this case.
*
* Note: BeginLateWriteChecks() must have been invoked before this function.
*/
void BeginLateWriteChecks();
/**
* Stop recording all writes as late-writes, call this function when you want
* late-write checks to stop. I.e. exception handling, or the special case on
* Mac described in bug 826029.
*/
void StopLateWriteChecks();
/**
* Temporarily suspend late write checks for the current thread. This is useful
* if you're about to perform a write, but it would be fine if this write were
* interrupted or skipped during a fast shutdown.
*/
void PushSuspendLateWriteChecks();
/**
* Resume late write checks for the current thread, assuming an ancestor in the
* call stack hasn't also pushed a suspension.
*/
void PopSuspendLateWriteChecks();
class MOZ_RAII AutoSuspendLateWriteChecks {
public:
AutoSuspendLateWriteChecks() { PushSuspendLateWriteChecks(); }
~AutoSuspendLateWriteChecks() { PopSuspendLateWriteChecks(); }
};
} // namespace mozilla
#endif // mozilla_LateWriteChecks_h