diagnostics/cros_healthd/process/process_with_output.h

// Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef DIAGNOSTICS_CROS_HEALTHD_PROCESS_PROCESS_WITH_OUTPUT_H_
#define DIAGNOSTICS_CROS_HEALTHD_PROCESS_PROCESS_WITH_OUTPUT_H_

#include <string>
#include <vector>

#include <base/files/file_path.h>
#include <base/files/scoped_file.h>
#include <brillo/errors/error.h>

#include "diagnostics/cros_healthd/process/sandboxed_process.h"

namespace diagnostics {

// Represents a process whose output can be collected.
//
// The process must be Run() to completion before its output can be collected.
// By default both stdout and stderr are included in the output.
// TODO(crbug.com/1093433): Create unit tests
class ProcessWithOutput : public SandboxedProcess {
 public:
  using ArgList = std::vector<std::string>;

  static constexpr int kRunError = -1;

  ProcessWithOutput();
  ~ProcessWithOutput() override;
  bool Init() override;
  bool Init(const std::vector<std::string>& minijail_extra_args) override;
  bool GetOutput(std::string* output) const;
  bool GetOutputLines(std::vector<std::string>* output) const;

  // Reads the stderr output. Must have called set_separate_stderr(true) and
  // run the process to completion.
  bool GetError(std::string* error);

  // Separates stderr from stdout. Must be called before Init() to have effect.
  void set_separate_stderr(bool separate_stderr) {
    separate_stderr_ = separate_stderr;
  }

  // Initializes, configures, and runs a ProcessWithOutput. If |disable_sandbox|
  // is set, |requires_root| will be ignored. The D-Bus error will only be set
  // if process setup fails, it's up to the caller to check the process exit
  // code and handle run failures as needed.
  // |stdin| is a string to pipe into the process, and |stdout| and |stderr|
  // will be filled with the corresponding process output. |error| will be
  // set if process setup fails and the process was never able to run. All
  // four of these parameters can be null.
  // Returns the process exit code or kRunError on setup failure.
  static int RunProcess(const std::string& command,
                        const ArgList& arguments,
                        bool requires_root,
                        const std::string* stdin,
                        std::string* stdout,
                        std::string* stderr,
                        brillo::ErrorPtr* error);

 private:
  base::FilePath outfile_path_, errfile_path_;
  base::ScopedFILE outfile_, errfile_;
  bool separate_stderr_;

  // Private function to do the work of running the process and handling I/O.
  static int DoRunProcess(const std::string& command,
                          const ArgList& arguments,
                          const std::string* stdin,
                          std::string* stdout,
                          std::string* stderr,
                          brillo::ErrorPtr* error,
                          ProcessWithOutput* process);
};

}  // namespace diagnostics

#endif  // DIAGNOSTICS_CROS_HEALTHD_PROCESS_PROCESS_WITH_OUTPUT_H_