sandboxed-api/sandboxed_api/sandbox2/fork_client.h
Christian Blichmann b74cf8839b Minor ForkClient improvements
- Use a `constexpr inline` string constant for the forkserver env var
- Add annotation for the comms channel mutex

PiperOrigin-RevId: 335395005
Change-Id: Ic058c19c3704f182aa7ed7b8e8964b2fc5082800
2020-10-05 05:10:16 -07:00

52 lines
1.6 KiB
C++

// Copyright 2020 Google LLC
//
// 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 SANDBOXED_API_SANDBOX2_FORK_CLIENT_H_
#define SANDBOXED_API_SANDBOX2_FORK_CLIENT_H_
#include <sys/types.h>
#include "absl/base/thread_annotations.h"
#include "absl/synchronization/mutex.h"
namespace sandbox2 {
// Envvar indicating that this process should not start the fork-server.
constexpr inline char kForkServerDisableEnv[] = "SANDBOX2_NOFORKSERVER";
class Comms;
class ForkRequest;
class ForkClient {
public:
explicit ForkClient(Comms* comms) : comms_(comms) {}
ForkClient(const ForkClient&) = delete;
ForkClient& operator=(const ForkClient&) = delete;
// Sends the fork request over the supplied Comms channel.
pid_t SendRequest(const ForkRequest& request, int exec_fd, int comms_fd,
int user_ns_fd = -1, pid_t* init_pid = nullptr);
private:
// Comms channel connecting with the ForkServer. Not owned by the object.
Comms* comms_ ABSL_GUARDED_BY(comms_mutex_);
// Mutex locking transactions (requests) over the Comms channel.
absl::Mutex comms_mutex_;
};
} // namespace sandbox2
#endif // SANDBOXED_API_SANDBOX2_FORK_CLIENT_H_