croslog/viewer_journal.cc

// Copyright 2020 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "croslog/viewer_journal.h"

#include <string>
#include <vector>

#include <base/process/launch.h>
#include <base/strings/string_number_conversions.h>

namespace croslog {

namespace {
static const char* kJournalctlCmdPath = "/usr/bin/journalctl";
}

bool ViewerJournal::Run(const Config& config) {
  std::vector<std::string> journalctl_command_line = {kJournalctlCmdPath};

  if (config.output != croslog::OutputMode::SHORT) {
    journalctl_command_line.push_back("--output");
    std::string output_mode;
    if (config.output == croslog::OutputMode::EXPORT)
      output_mode = "export";
    else if (config.output == croslog::OutputMode::JSON)
      output_mode = "json";
    else
      output_mode = "short";
    journalctl_command_line.push_back(output_mode);
  }

  if (config.lines >= 0) {
    journalctl_command_line.push_back("--lines");
    journalctl_command_line.push_back(base::NumberToString(config.lines));
  }

  if (config.boot.has_value()) {
    journalctl_command_line.push_back("--boot");
    if (!config.boot->empty())
      journalctl_command_line.push_back(config.boot.value());
  }

  if (!config.identifier.empty()) {
    journalctl_command_line.push_back("--identifier");
    journalctl_command_line.push_back(config.identifier);
  }

  if (config.severity != croslog::Severity::UNSPECIFIED) {
    journalctl_command_line.push_back("--priority");
    journalctl_command_line.push_back(
        base::NumberToString(static_cast<int>(config.severity)));
  }

  if (!config.grep.empty()) {
    journalctl_command_line.push_back("--grep");
    journalctl_command_line.push_back(config.grep);
  }

  if (!config.cursor.empty()) {
    journalctl_command_line.push_back("--cursor");
    journalctl_command_line.push_back(config.cursor);
  }

  if (!config.after_cursor.empty()) {
    journalctl_command_line.push_back("--after-cursor");
    journalctl_command_line.push_back(config.after_cursor);
  }

  if (config.show_cursor) {
    journalctl_command_line.push_back("--show-cursor");
  }

  if (config.quiet) {
    journalctl_command_line.push_back("--quiet");
  }

  if (config.no_pager) {
    journalctl_command_line.push_back("--no-pager");
  }

  if (config.follow) {
    journalctl_command_line.push_back("--follow");
  }

  base::Process process(
      base::LaunchProcess(journalctl_command_line, base::LaunchOptions()));
  if (!process.IsValid())
    return false;
  int exit_code = -1;
  return process.WaitForExit(&exit_code) && (exit_code == 0);
}

}  // namespace croslog