110 lines
2.8 KiB
C++
110 lines
2.8 KiB
C++
/*
|
|
* Copyright (C) 2016 The Android Open Source Project
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#ifndef LIBMEMUNREACHABLE_SCOPED_DISABLE_MALLOC_H_
|
|
#define LIBMEMUNREACHABLE_SCOPED_DISABLE_MALLOC_H_
|
|
|
|
#include <memory>
|
|
|
|
#include "android-base/macros.h"
|
|
|
|
#include "ScopedAlarm.h"
|
|
#include "bionic.h"
|
|
#include "log.h"
|
|
|
|
namespace android {
|
|
|
|
class DisableMallocGuard {
|
|
public:
|
|
DisableMallocGuard() : disabled_(false) {}
|
|
~DisableMallocGuard() { Enable(); }
|
|
|
|
void Disable() {
|
|
if (!disabled_) {
|
|
malloc_disable();
|
|
disabled_ = true;
|
|
}
|
|
}
|
|
|
|
void Enable() {
|
|
if (disabled_) {
|
|
malloc_enable();
|
|
disabled_ = false;
|
|
}
|
|
}
|
|
|
|
private:
|
|
DISALLOW_COPY_AND_ASSIGN(DisableMallocGuard);
|
|
bool disabled_;
|
|
};
|
|
|
|
// Any calls to malloc or free from this thread will deadlock as long as this
|
|
// object is in scope. Calls to malloc from other threads may succeed (for
|
|
// example if the allocation is satisfied out of the thread's tcache), or may
|
|
// block until the object is destroyed.
|
|
//
|
|
// Don't call fork() while malloc is disabled, it needs the same locks held
|
|
// here.
|
|
class ScopedDisableMalloc {
|
|
public:
|
|
ScopedDisableMalloc() { disable_malloc_.Disable(); }
|
|
|
|
~ScopedDisableMalloc() { disable_malloc_.Enable(); }
|
|
|
|
private:
|
|
DISALLOW_COPY_AND_ASSIGN(ScopedDisableMalloc);
|
|
DisableMallocGuard disable_malloc_;
|
|
};
|
|
|
|
class ScopedDisableMallocTimeout {
|
|
public:
|
|
explicit ScopedDisableMallocTimeout(
|
|
std::chrono::milliseconds timeout = std::chrono::milliseconds(2000))
|
|
: timeout_(timeout), timed_out_(false), disable_malloc_() {
|
|
Disable();
|
|
}
|
|
|
|
~ScopedDisableMallocTimeout() { Enable(); }
|
|
|
|
bool timed_out() { return timed_out_; }
|
|
|
|
void Enable() {
|
|
disable_malloc_.Enable();
|
|
alarm_ = nullptr;
|
|
}
|
|
|
|
void Disable() {
|
|
// set up the alarm before disabling malloc so unique_ptr can be used
|
|
alarm_ = std::make_unique<ScopedAlarm>(timeout_, [&]() {
|
|
disable_malloc_.Enable();
|
|
timed_out_ = true;
|
|
});
|
|
|
|
disable_malloc_.Disable();
|
|
}
|
|
|
|
private:
|
|
DISALLOW_COPY_AND_ASSIGN(ScopedDisableMallocTimeout);
|
|
std::chrono::milliseconds timeout_;
|
|
bool timed_out_;
|
|
std::unique_ptr<ScopedAlarm> alarm_;
|
|
DisableMallocGuard disable_malloc_;
|
|
};
|
|
|
|
} // namespace android
|
|
|
|
#endif // LIBMEMUNREACHABLE_SCOPED_DISABLE_MALLOC_H_
|