gecko-dev/mfbt/Assertions.cpp
David Major 0f1c6a1f28 Bug 1646171 - Fix vsnprintf complaint in Assertions.cpp r=froydnj
For some reason, our clang-plugin didn't notice this before clang 11.

Differential Revision: https://phabricator.services.mozilla.com/D79901
2020-06-16 21:26:16 +00:00

47 lines
1.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#include "mozilla/Assertions.h"
#include "mozilla/Atomics.h"
#include "mozilla/Sprintf.h"
#include <stdarg.h>
MOZ_BEGIN_EXTERN_C
/*
* The crash reason is defined as a global variable here rather than in the
* crash reporter itself to make it available to all code, even libraries like
* JS that don't link with the crash reporter directly. This value will only
* be consumed if the crash reporter is used by the target application.
*/
MFBT_DATA const char* gMozCrashReason = nullptr;
static char sPrintfCrashReason[sPrintfCrashReasonSize] = {};
// Accesses to this atomic are not included in web replay recordings, so that
// if we crash in an area where recorded events are not allowed the true reason
// for the crash is not obscured by a record/replay error.
static mozilla::Atomic<bool, mozilla::SequentiallyConsistent> sCrashing(false);
MFBT_API MOZ_COLD MOZ_NEVER_INLINE MOZ_FORMAT_PRINTF(1, 2) const
char* MOZ_CrashPrintf(const char* aFormat, ...) {
if (!sCrashing.compareExchange(false, true)) {
// In the unlikely event of a race condition, skip
// setting the crash reason and just crash safely.
MOZ_RELEASE_ASSERT(false);
}
va_list aArgs;
va_start(aArgs, aFormat);
int ret = VsprintfLiteral(sPrintfCrashReason, aFormat, aArgs);
va_end(aArgs);
MOZ_RELEASE_ASSERT(
ret >= 0 && size_t(ret) < sPrintfCrashReasonSize,
"Could not write the explanation string to the supplied buffer!");
return sPrintfCrashReason;
}
MOZ_END_EXTERN_C