runtime/exec_utils.h

/*
 * Copyright (C) 2017 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 ART_RUNTIME_EXEC_UTILS_H_
#define ART_RUNTIME_EXEC_UTILS_H_

#include <time.h>

#include <string>
#include <vector>

#include "android-base/unique_fd.h"

namespace art {

// Wrapper on fork/execv to run a command in a subprocess.
// These spawn child processes using the environment as it was set when the single instance
// of the runtime (Runtime::Current()) was started.  If no instance of the runtime was started, it
// will use the current environment settings.
class ExecUtils {
 public:
  virtual ~ExecUtils() = default;

  virtual bool Exec(const std::vector<std::string>& arg_vector,
                    /*out*/ std::string* error_msg) const;

  virtual int ExecAndReturnCode(const std::vector<std::string>& arg_vector,
                                /*out*/ std::string* error_msg) const;

  // Executes the command specified in `arg_vector` in a subprocess with a timeout.
  // If `timeout_sec` is negative, blocks until the subprocess exits.
  // Returns the process exit code on success, -1 otherwise.
  // Sets `timed_out` to true if the process times out, or false otherwise.
  virtual int ExecAndReturnCode(const std::vector<std::string>& arg_vector,
                                int timeout_sec,
                                /*out*/ bool* timed_out,
                                /*out*/ std::string* error_msg) const;

 protected:
  virtual android::base::unique_fd PidfdOpen(pid_t pid) const;
};

inline bool Exec(const std::vector<std::string>& arg_vector, /*out*/ std::string* error_msg) {
  return ExecUtils().Exec(arg_vector, error_msg);
}

inline int ExecAndReturnCode(const std::vector<std::string>& arg_vector,
                             /*out*/ std::string* error_msg) {
  return ExecUtils().ExecAndReturnCode(arg_vector, error_msg);
}

}  // namespace art

#endif  // ART_RUNTIME_EXEC_UTILS_H_