crashpad/util/fuchsia/scoped_task_suspend.h
Scott Graham 922b5750c1 fuchsia: Update for zx_task_suspend() supporting processes
zx_task_suspend() now supports suspending processes. This is somewhat
more reliable than suspending the constituent threads because after the
call returns and the token is being held, any subsequently started
threads will start in the the suspended state.

However, because the suspend is asynchronous the threads of the process
still need to be iterated to wait for them to assert ZX_THREAD_SUSPENDED
(and that can and does still fail to happen for a number of reasons). So
while improved, this class is still only best-effort.

Additionally, as the version of ScopedTaskSuspend that took a thread
wasn't being used, remove that.

Bug: crashpad:269
Change-Id: Ifb3f8e0d780a5e22af33613f92a61d25459f5139
Reviewed-on: https://chromium-review.googlesource.com/c/1377201
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Scott Graham <scottmg@chromium.org>
2019-01-14 22:32:15 +00:00

50 lines
1.5 KiB
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// Copyright 2018 The Crashpad Authors. All rights reserved.
//
// 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 CRASHPAD_UTIL_FUCHSIA_SCOPED_TASK_SUSPEND_H_
#define CRASHPAD_UTIL_FUCHSIA_SCOPED_TASK_SUSPEND_H_
#include <lib/zx/process.h>
#include <lib/zx/suspend_token.h>
#include <lib/zx/thread.h>
#include <vector>
#include "base/macros.h"
namespace crashpad {
//! \brief Manages the suspension of another task.
//!
//! Suspending a process is asynchronous, and may take an arbitrary amount of
//! time. As a result, this class is limited to being a best-effort, and
//! correct suspension/resumption cannot be relied upon.
//!
//! Callers should not attempt to suspend the current task as obtained via
//! `zx_process_self()`.
class ScopedTaskSuspend {
public:
explicit ScopedTaskSuspend(const zx::process& process);
~ScopedTaskSuspend() = default;
private:
zx::suspend_token suspend_token_;
DISALLOW_COPY_AND_ASSIGN(ScopedTaskSuspend);
};
} // namespace crashpad
#endif // CRASHPAD_UTIL_FUCHSIA_SCOPED_TASK_SUSPEND_H_