root/chrome/browser/shell_integration_linux.cc

DEFINITIONS

1. LaunchXdgUtility
2. CreateShortcutIcon
3. CreateShortcutOnDesktop
4. DeleteShortcutOnDesktop
5. CreateShortcutInApplicationsMenu
6. DeleteShortcutInApplicationsMenu
7. QuoteArgForDesktopFileExec
8. QuoteCommandLineForDesktopFileExec
9. GetChromeVersionOfScript
10. SetDefaultWebClient
11. GetIsDefaultWebClient
12. GetNoDisplayFromDesktopFile
13. GetChromeExePath
14. CanSetAsDefaultBrowser
15. SetAsDefaultBrowser
16. SetAsDefaultProtocolClient
17. GetDefaultBrowser
18. GetApplicationNameForProtocol
19. IsDefaultProtocolClient
20. IsFirefoxDefaultBrowser
21. GetDataWriteLocation
22. GetDataSearchLocations
23. GetProgramClassName
24. GetDesktopName
25. GetIconName
26. GetExistingShortcutLocations
27. GetExistingShortcutLocations
28. GetExistingShortcutContents
29. GetWebShortcutFilename
30. GetExtensionShortcutFilename
31. GetExistingProfileShortcutFilenames
32. GetDesktopFileContents
33. GetDesktopFileContentsForCommand
34. GetDirectoryFileContents
35. CreateDesktopShortcut
36. CreateAppListDesktopShortcut
37. DeleteDesktopShortcuts
38. DeleteAllDesktopShortcuts

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

#include "chrome/browser/shell_integration_linux.h"

#include <fcntl.h>
#include <glib.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include <string>
#include <vector>

#include "base/base_paths.h"
#include "base/command_line.h"
#include "base/environment.h"
#include "base/file_util.h"
#include "base/files/file_enumerator.h"
#include "base/files/file_path.h"
#include "base/files/scoped_temp_dir.h"
#include "base/i18n/file_util_icu.h"
#include "base/memory/ref_counted_memory.h"
#include "base/memory/scoped_ptr.h"
#include "base/message_loop/message_loop.h"
#include "base/path_service.h"
#include "base/posix/eintr_wrapper.h"
#include "base/process/kill.h"
#include "base/process/launch.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_tokenizer.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "base/threading/thread.h"
#include "base/threading/thread_restrictions.h"
#include "build/build_config.h"
#include "chrome/browser/web_applications/web_app.h"
#include "chrome/common/chrome_constants.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/common/chrome_version_info.h"
#include "content/public/browser/browser_thread.h"
#include "grit/chrome_unscaled_resources.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/gfx/image/image_family.h"
#include "url/gurl.h"

using content::BrowserThread;

namespace {

// Helper to launch xdg scripts. We don't want them to ask any questions on the
// terminal etc. The function returns true if the utility launches and exits
// cleanly, in which case |exit_code| returns the utility's exit code.
bool LaunchXdgUtility(const std::vector<std::string>& argv, int* exit_code) {
  // xdg-settings internally runs xdg-mime, which uses mv to move newly-created
  // files on top of originals after making changes to them. In the event that
  // the original files are owned by another user (e.g. root, which can happen
  // if they are updated within sudo), mv will prompt the user to confirm if
  // standard input is a terminal (otherwise it just does it). So make sure it's
  // not, to avoid locking everything up waiting for mv.
  *exit_code = EXIT_FAILURE;
  int devnull = open("/dev/null", O_RDONLY);
  if (devnull < 0)
    return false;
  base::FileHandleMappingVector no_stdin;
  no_stdin.push_back(std::make_pair(devnull, STDIN_FILENO));

  base::ProcessHandle handle;
  base::LaunchOptions options;
  options.fds_to_remap = &no_stdin;
  if (!base::LaunchProcess(argv, options, &handle)) {
    close(devnull);
    return false;
  }
  close(devnull);

  return base::WaitForExitCode(handle, exit_code);
}

std::string CreateShortcutIcon(const gfx::ImageFamily& icon_images,
                               const base::FilePath& shortcut_filename) {
  if (icon_images.empty())
    return std::string();

  // TODO(phajdan.jr): Report errors from this function, possibly as infobars.
  base::ScopedTempDir temp_dir;
  if (!temp_dir.CreateUniqueTempDir())
    return std::string();

  base::FilePath temp_file_path = temp_dir.path().Append(
      shortcut_filename.ReplaceExtension("png"));
  std::string icon_name = temp_file_path.BaseName().RemoveExtension().value();

  for (gfx::ImageFamily::const_iterator it = icon_images.begin();
       it != icon_images.end(); ++it) {
    int width = it->Width();
    scoped_refptr<base::RefCountedMemory> png_data = it->As1xPNGBytes();
    if (png_data->size() == 0) {
      // If the bitmap could not be encoded to PNG format, skip it.
      LOG(WARNING) << "Could not encode icon " << icon_name << ".png at size "
                   << width << ".";
      continue;
    }
    int bytes_written = base::WriteFile(temp_file_path,
                                        png_data->front_as<char>(),
                                        png_data->size());

    if (bytes_written != static_cast<int>(png_data->size()))
      return std::string();

    std::vector<std::string> argv;
    argv.push_back("xdg-icon-resource");
    argv.push_back("install");

    // Always install in user mode, even if someone runs the browser as root
    // (people do that).
    argv.push_back("--mode");
    argv.push_back("user");

    argv.push_back("--size");
    argv.push_back(base::IntToString(width));

    argv.push_back(temp_file_path.value());
    argv.push_back(icon_name);
    int exit_code;
    if (!LaunchXdgUtility(argv, &exit_code) || exit_code) {
      LOG(WARNING) << "Could not install icon " << icon_name << ".png at size "
                   << width << ".";
    }
  }
  return icon_name;
}

bool CreateShortcutOnDesktop(const base::FilePath& shortcut_filename,
                             const std::string& contents) {
  // Make sure that we will later call openat in a secure way.
  DCHECK_EQ(shortcut_filename.BaseName().value(), shortcut_filename.value());

  base::FilePath desktop_path;
  if (!PathService::Get(base::DIR_USER_DESKTOP, &desktop_path))
    return false;

  int desktop_fd = open(desktop_path.value().c_str(), O_RDONLY | O_DIRECTORY);
  if (desktop_fd < 0)
    return false;

  int fd = openat(desktop_fd, shortcut_filename.value().c_str(),
                  O_CREAT | O_EXCL | O_WRONLY,
                  S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
  if (fd < 0) {
    if (IGNORE_EINTR(close(desktop_fd)) < 0)
      PLOG(ERROR) << "close";
    return false;
  }

  ssize_t bytes_written = base::WriteFileDescriptor(fd, contents.data(),
                                                    contents.length());
  if (IGNORE_EINTR(close(fd)) < 0)
    PLOG(ERROR) << "close";

  if (bytes_written != static_cast<ssize_t>(contents.length())) {
    // Delete the file. No shortuct is better than corrupted one. Use unlinkat
    // to make sure we're deleting the file in the directory we think we are.
    // Even if an attacker manager to put something other at
    // |shortcut_filename| we'll just undo his action.
    unlinkat(desktop_fd, shortcut_filename.value().c_str(), 0);
  }

  if (IGNORE_EINTR(close(desktop_fd)) < 0)
    PLOG(ERROR) << "close";

  return true;
}

void DeleteShortcutOnDesktop(const base::FilePath& shortcut_filename) {
  base::FilePath desktop_path;
  if (PathService::Get(base::DIR_USER_DESKTOP, &desktop_path))
    base::DeleteFile(desktop_path.Append(shortcut_filename), false);
}

// Creates a shortcut with |shortcut_filename| and |contents| in the system
// applications menu. If |directory_filename| is non-empty, creates a sub-menu
// with |directory_filename| and |directory_contents|, and stores the shortcut
// under the sub-menu.
bool CreateShortcutInApplicationsMenu(const base::FilePath& shortcut_filename,
                                      const std::string& contents,
                                      const base::FilePath& directory_filename,
                                      const std::string& directory_contents) {
  base::ScopedTempDir temp_dir;
  if (!temp_dir.CreateUniqueTempDir())
    return false;

  base::FilePath temp_directory_path;
  if (!directory_filename.empty()) {
    temp_directory_path = temp_dir.path().Append(directory_filename);

    int bytes_written = base::WriteFile(temp_directory_path,
                                        directory_contents.data(),
                                        directory_contents.length());

    if (bytes_written != static_cast<int>(directory_contents.length()))
      return false;
  }

  base::FilePath temp_file_path = temp_dir.path().Append(shortcut_filename);

  int bytes_written = base::WriteFile(temp_file_path, contents.data(),
                                      contents.length());

  if (bytes_written != static_cast<int>(contents.length()))
    return false;

  std::vector<std::string> argv;
  argv.push_back("xdg-desktop-menu");
  argv.push_back("install");

  // Always install in user mode, even if someone runs the browser as root
  // (people do that).
  argv.push_back("--mode");
  argv.push_back("user");

  // If provided, install the shortcut file inside the given directory.
  if (!directory_filename.empty())
    argv.push_back(temp_directory_path.value());
  argv.push_back(temp_file_path.value());
  int exit_code;
  LaunchXdgUtility(argv, &exit_code);
  return exit_code == 0;
}

void DeleteShortcutInApplicationsMenu(
    const base::FilePath& shortcut_filename,
    const base::FilePath& directory_filename) {
  std::vector<std::string> argv;
  argv.push_back("xdg-desktop-menu");
  argv.push_back("uninstall");

  // Uninstall in user mode, to match the install.
  argv.push_back("--mode");
  argv.push_back("user");

  // The file does not need to exist anywhere - xdg-desktop-menu will uninstall
  // items from the menu with a matching name.
  // If |directory_filename| is supplied, this will also remove the item from
  // the directory, and remove the directory if it is empty.
  if (!directory_filename.empty())
    argv.push_back(directory_filename.value());
  argv.push_back(shortcut_filename.value());
  int exit_code;
  LaunchXdgUtility(argv, &exit_code);
}

// Quote a string such that it appears as one verbatim argument for the Exec
// key in a desktop file.
std::string QuoteArgForDesktopFileExec(const std::string& arg) {
  // http://standards.freedesktop.org/desktop-entry-spec/latest/ar01s06.html

  // Quoting is only necessary if the argument has a reserved character.
  if (arg.find_first_of(" \t\n\"'\\><~|&;$*?#()`") == std::string::npos)
    return arg;  // No quoting necessary.

  std::string quoted = "\"";
  for (size_t i = 0; i < arg.size(); ++i) {
    // Note that the set of backslashed characters is smaller than the
    // set of reserved characters.
    switch (arg[i]) {
      case '"':
      case '`':
      case '$':
      case '\\':
        quoted += '\\';
        break;
    }
    quoted += arg[i];
  }
  quoted += '"';

  return quoted;
}

// Quote a command line so it is suitable for use as the Exec key in a desktop
// file. Note: This should be used instead of GetCommandLineString, which does
// not properly quote the string; this function is designed for the Exec key.
std::string QuoteCommandLineForDesktopFileExec(
    const CommandLine& command_line) {
  // http://standards.freedesktop.org/desktop-entry-spec/latest/ar01s06.html

  std::string quoted_path = "";
  const CommandLine::StringVector& argv = command_line.argv();
  for (CommandLine::StringVector::const_iterator i = argv.begin();
       i != argv.end(); ++i) {
    if (i != argv.begin())
      quoted_path += " ";
    quoted_path += QuoteArgForDesktopFileExec(*i);
  }

  return quoted_path;
}

const char kDesktopEntry[] = "Desktop Entry";

const char kXdgOpenShebang[] = "#!/usr/bin/env xdg-open";

const char kXdgSettings[] = "xdg-settings";
const char kXdgSettingsDefaultBrowser[] = "default-web-browser";
const char kXdgSettingsDefaultSchemeHandler[] = "default-url-scheme-handler";

const char kDirectoryFilename[] = "chrome-apps.directory";

#if defined(GOOGLE_CHROME_BUILD)
const char kAppListDesktopName[] = "chrome-app-list";
#else  // CHROMIUM_BUILD
const char kAppListDesktopName[] = "chromium-app-list";
#endif

}  // namespace

namespace {

// Utility function to get the path to the version of a script shipped with
// Chrome. |script| gives the name of the script. |chrome_version| returns the
// path to the Chrome version of the script, and the return value of the
// function is true if the function is successful and the Chrome version is
// not the script found on the PATH.
bool GetChromeVersionOfScript(const std::string& script,
                               std::string* chrome_version) {
  // Get the path to the Chrome version.
  base::FilePath chrome_dir;
  if (!PathService::Get(base::DIR_EXE, &chrome_dir))
    return false;

  base::FilePath chrome_version_path = chrome_dir.Append(script);
  *chrome_version = chrome_version_path.value();

  // Check if this is different to the one on path.
  std::vector<std::string> argv;
  argv.push_back("which");
  argv.push_back(script);
  std::string path_version;
  if (base::GetAppOutput(CommandLine(argv), &path_version)) {
    // Remove trailing newline
    path_version.erase(path_version.length() - 1, 1);
    base::FilePath path_version_path(path_version);
    return (chrome_version_path != path_version_path);
  }
  return false;
}

// Value returned by xdg-settings if it can't understand our request.
const int EXIT_XDG_SETTINGS_SYNTAX_ERROR = 1;

// We delegate the difficulty of setting the default browser and default url
// scheme handler in Linux desktop environments to an xdg utility, xdg-settings.

// When calling this script we first try to use the script on PATH. If that
// fails we then try to use the script that we have included. This gives
// scripts on the system priority over ours, as distribution vendors may have
// tweaked the script, but still allows our copy to be used if the script on the
// system fails, as the system copy may be missing capabilities of the Chrome
// copy.

// If |protocol| is empty this function sets Chrome as the default browser,
// otherwise it sets Chrome as the default handler application for |protocol|.
bool SetDefaultWebClient(const std::string& protocol) {
#if defined(OS_CHROMEOS)
  return true;
#else
  scoped_ptr<base::Environment> env(base::Environment::Create());

  std::vector<std::string> argv;
  argv.push_back(kXdgSettings);
  argv.push_back("set");
  if (protocol.empty()) {
    argv.push_back(kXdgSettingsDefaultBrowser);
  } else {
    argv.push_back(kXdgSettingsDefaultSchemeHandler);
    argv.push_back(protocol);
  }
  argv.push_back(ShellIntegrationLinux::GetDesktopName(env.get()));

  int exit_code;
  bool ran_ok = LaunchXdgUtility(argv, &exit_code);
  if (ran_ok && exit_code == EXIT_XDG_SETTINGS_SYNTAX_ERROR) {
    if (GetChromeVersionOfScript(kXdgSettings, &argv[0])) {
      ran_ok = LaunchXdgUtility(argv, &exit_code);
    }
  }

  return ran_ok && exit_code == EXIT_SUCCESS;
#endif
}

// If |protocol| is empty this function checks if Chrome is the default browser,
// otherwise it checks if Chrome is the default handler application for
// |protocol|.
ShellIntegration::DefaultWebClientState GetIsDefaultWebClient(
    const std::string& protocol) {
#if defined(OS_CHROMEOS)
  return ShellIntegration::UNKNOWN_DEFAULT;
#else
  base::ThreadRestrictions::AssertIOAllowed();

  scoped_ptr<base::Environment> env(base::Environment::Create());

  std::vector<std::string> argv;
  argv.push_back(kXdgSettings);
  argv.push_back("check");
  if (protocol.empty()) {
    argv.push_back(kXdgSettingsDefaultBrowser);
  } else {
    argv.push_back(kXdgSettingsDefaultSchemeHandler);
    argv.push_back(protocol);
  }
  argv.push_back(ShellIntegrationLinux::GetDesktopName(env.get()));

  std::string reply;
  int success_code;
  bool ran_ok = base::GetAppOutputWithExitCode(CommandLine(argv), &reply,
                                               &success_code);
  if (ran_ok && success_code == EXIT_XDG_SETTINGS_SYNTAX_ERROR) {
    if (GetChromeVersionOfScript(kXdgSettings, &argv[0])) {
      ran_ok = base::GetAppOutputWithExitCode(CommandLine(argv), &reply,
                                              &success_code);
    }
  }

  if (!ran_ok || success_code != EXIT_SUCCESS) {
    // xdg-settings failed: we can't determine or set the default browser.
    return ShellIntegration::UNKNOWN_DEFAULT;
  }

  // Allow any reply that starts with "yes".
  return (reply.find("yes") == 0) ? ShellIntegration::IS_DEFAULT :
                                    ShellIntegration::NOT_DEFAULT;
#endif
}

// Get the value of NoDisplay from the [Desktop Entry] section of a .desktop
// file, given in |shortcut_contents|. If the key is not found, returns false.
bool GetNoDisplayFromDesktopFile(const std::string& shortcut_contents) {
  // An empty file causes a crash with glib <= 2.32, so special case here.
  if (shortcut_contents.empty())
    return false;

  GKeyFile* key_file = g_key_file_new();
  GError* err = NULL;
  if (!g_key_file_load_from_data(key_file, shortcut_contents.c_str(),
                                 shortcut_contents.size(), G_KEY_FILE_NONE,
                                 &err)) {
    LOG(WARNING) << "Unable to read desktop file template: " << err->message;
    g_error_free(err);
    g_key_file_free(key_file);
    return false;
  }

  bool nodisplay = false;
  char* nodisplay_c_string = g_key_file_get_string(key_file, kDesktopEntry,
                                                   "NoDisplay", &err);
  if (nodisplay_c_string) {
    if (!g_strcmp0(nodisplay_c_string, "true"))
      nodisplay = true;
    g_free(nodisplay_c_string);
  } else {
    g_error_free(err);
  }

  g_key_file_free(key_file);
  return nodisplay;
}

// Gets the path to the Chrome executable or wrapper script.
// Returns an empty path if the executable path could not be found.
base::FilePath GetChromeExePath() {
  // Try to get the name of the wrapper script that launched Chrome.
  scoped_ptr<base::Environment> environment(base::Environment::Create());
  std::string wrapper_script;
  if (environment->GetVar("CHROME_WRAPPER", &wrapper_script)) {
    return base::FilePath(wrapper_script);
  }

  // Just return the name of the executable path for Chrome.
  base::FilePath chrome_exe_path;
  PathService::Get(base::FILE_EXE, &chrome_exe_path);
  return chrome_exe_path;
}

} // namespace

// static
ShellIntegration::DefaultWebClientSetPermission
    ShellIntegration::CanSetAsDefaultBrowser() {
  return SET_DEFAULT_UNATTENDED;
}

// static
bool ShellIntegration::SetAsDefaultBrowser() {
  return SetDefaultWebClient(std::string());
}

// static
bool ShellIntegration::SetAsDefaultProtocolClient(const std::string& protocol) {
  return SetDefaultWebClient(protocol);
}

// static
ShellIntegration::DefaultWebClientState ShellIntegration::GetDefaultBrowser() {
  return GetIsDefaultWebClient(std::string());
}

// static
base::string16 ShellIntegration::GetApplicationNameForProtocol(
    const GURL& url) {
  return base::ASCIIToUTF16("xdg-open");
}

// static
ShellIntegration::DefaultWebClientState
ShellIntegration::IsDefaultProtocolClient(const std::string& protocol) {
  return GetIsDefaultWebClient(protocol);
}

// static
bool ShellIntegration::IsFirefoxDefaultBrowser() {
  std::vector<std::string> argv;
  argv.push_back(kXdgSettings);
  argv.push_back("get");
  argv.push_back(kXdgSettingsDefaultBrowser);

  std::string browser;
  // We don't care about the return value here.
  base::GetAppOutput(CommandLine(argv), &browser);
  return browser.find("irefox") != std::string::npos;
}

namespace ShellIntegrationLinux {

bool GetDataWriteLocation(base::Environment* env, base::FilePath* search_path) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  std::string xdg_data_home;
  std::string home;
  if (env->GetVar("XDG_DATA_HOME", &xdg_data_home) && !xdg_data_home.empty()) {
    *search_path = base::FilePath(xdg_data_home);
    return true;
  } else if (env->GetVar("HOME", &home) && !home.empty()) {
    *search_path = base::FilePath(home).Append(".local").Append("share");
    return true;
  }
  return false;
}

std::vector<base::FilePath> GetDataSearchLocations(base::Environment* env) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  std::vector<base::FilePath> search_paths;

  base::FilePath write_location;
  if (GetDataWriteLocation(env, &write_location))
    search_paths.push_back(write_location);

  std::string xdg_data_dirs;
  if (env->GetVar("XDG_DATA_DIRS", &xdg_data_dirs) && !xdg_data_dirs.empty()) {
    base::StringTokenizer tokenizer(xdg_data_dirs, ":");
    while (tokenizer.GetNext()) {
      base::FilePath data_dir(tokenizer.token());
      search_paths.push_back(data_dir);
    }
  } else {
    search_paths.push_back(base::FilePath("/usr/local/share"));
    search_paths.push_back(base::FilePath("/usr/share"));
  }

  return search_paths;
}

std::string GetProgramClassName() {
  DCHECK(CommandLine::InitializedForCurrentProcess());
  // Get the res_name component from argv[0].
  const CommandLine* command_line = CommandLine::ForCurrentProcess();
  std::string class_name = command_line->GetProgram().BaseName().value();
  if (!class_name.empty())
    class_name[0] = base::ToUpperASCII(class_name[0]);
  return class_name;
}

std::string GetDesktopName(base::Environment* env) {
#if defined(GOOGLE_CHROME_BUILD)
  chrome::VersionInfo::Channel product_channel(
      chrome::VersionInfo::GetChannel());
  switch (product_channel) {
    case chrome::VersionInfo::CHANNEL_DEV:
      return "google-chrome-unstable.desktop";
    case chrome::VersionInfo::CHANNEL_BETA:
      return "google-chrome-beta.desktop";
    default:
      return "google-chrome.desktop";
  }
#else  // CHROMIUM_BUILD
  // Allow $CHROME_DESKTOP to override the built-in value, so that development
  // versions can set themselves as the default without interfering with
  // non-official, packaged versions using the built-in value.
  std::string name;
  if (env->GetVar("CHROME_DESKTOP", &name) && !name.empty())
    return name;
  return "chromium-browser.desktop";
#endif
}

std::string GetIconName() {
#if defined(GOOGLE_CHROME_BUILD)
  return "google-chrome";
#else  // CHROMIUM_BUILD
  return "chromium-browser";
#endif
}

ShellIntegration::ShortcutLocations GetExistingShortcutLocations(
    base::Environment* env,
    const base::FilePath& profile_path,
    const std::string& extension_id) {
  base::FilePath desktop_path;
  // If Get returns false, just leave desktop_path empty.
  PathService::Get(base::DIR_USER_DESKTOP, &desktop_path);
  return GetExistingShortcutLocations(env, profile_path, extension_id,
                                      desktop_path);
}

ShellIntegration::ShortcutLocations GetExistingShortcutLocations(
    base::Environment* env,
    const base::FilePath& profile_path,
    const std::string& extension_id,
    const base::FilePath& desktop_path) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  base::FilePath shortcut_filename = GetExtensionShortcutFilename(
      profile_path, extension_id);
  DCHECK(!shortcut_filename.empty());
  ShellIntegration::ShortcutLocations locations;

  // Determine whether there is a shortcut on desktop.
  if (!desktop_path.empty()) {
    locations.on_desktop =
        base::PathExists(desktop_path.Append(shortcut_filename));
  }

  // Determine whether there is a shortcut in the applications directory.
  std::string shortcut_contents;
  if (GetExistingShortcutContents(env, shortcut_filename, &shortcut_contents)) {
    // Whether this counts as "hidden" or "APP_MENU_LOCATION_SUBDIR_CHROMEAPPS"
    // depends on whether it contains NoDisplay=true. Since these shortcuts are
    // for apps, they are always in the "Chrome Apps" directory.
    if (GetNoDisplayFromDesktopFile(shortcut_contents)) {
      locations.hidden = true;
    } else {
      locations.applications_menu_location =
          ShellIntegration::APP_MENU_LOCATION_SUBDIR_CHROMEAPPS;
    }
  }

  return locations;
}

bool GetExistingShortcutContents(base::Environment* env,
                                 const base::FilePath& desktop_filename,
                                 std::string* output) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  std::vector<base::FilePath> search_paths = GetDataSearchLocations(env);

  for (std::vector<base::FilePath>::const_iterator i = search_paths.begin();
       i != search_paths.end(); ++i) {
    base::FilePath path = i->Append("applications").Append(desktop_filename);
    VLOG(1) << "Looking for desktop file in " << path.value();
    if (base::PathExists(path)) {
      VLOG(1) << "Found desktop file at " << path.value();
      return base::ReadFileToString(path, output);
    }
  }

  return false;
}

base::FilePath GetWebShortcutFilename(const GURL& url) {
  // Use a prefix, because xdg-desktop-menu requires it.
  std::string filename =
      std::string(chrome::kBrowserProcessExecutableName) + "-" + url.spec();
  file_util::ReplaceIllegalCharactersInPath(&filename, '_');

  base::FilePath desktop_path;
  if (!PathService::Get(base::DIR_USER_DESKTOP, &desktop_path))
    return base::FilePath();

  base::FilePath filepath = desktop_path.Append(filename);
  base::FilePath alternative_filepath(filepath.value() + ".desktop");
  for (size_t i = 1; i < 100; ++i) {
    if (base::PathExists(base::FilePath(alternative_filepath))) {
      alternative_filepath = base::FilePath(
          filepath.value() + "_" + base::IntToString(i) + ".desktop");
    } else {
      return base::FilePath(alternative_filepath).BaseName();
    }
  }

  return base::FilePath();
}

base::FilePath GetExtensionShortcutFilename(const base::FilePath& profile_path,
                                            const std::string& extension_id) {
  DCHECK(!extension_id.empty());

  // Use a prefix, because xdg-desktop-menu requires it.
  std::string filename(chrome::kBrowserProcessExecutableName);
  filename.append("-")
      .append(extension_id)
      .append("-")
      .append(profile_path.BaseName().value());
  file_util::ReplaceIllegalCharactersInPath(&filename, '_');
  // Spaces in filenames break xdg-desktop-menu
  // (see https://bugs.freedesktop.org/show_bug.cgi?id=66605).
  base::ReplaceChars(filename, " ", "_", &filename);
  return base::FilePath(filename.append(".desktop"));
}

std::vector<base::FilePath> GetExistingProfileShortcutFilenames(
    const base::FilePath& profile_path,
    const base::FilePath& directory) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
  // Use a prefix, because xdg-desktop-menu requires it.
  std::string prefix(chrome::kBrowserProcessExecutableName);
  prefix.append("-");
  std::string suffix("-");
  suffix.append(profile_path.BaseName().value());
  file_util::ReplaceIllegalCharactersInPath(&suffix, '_');
  // Spaces in filenames break xdg-desktop-menu
  // (see https://bugs.freedesktop.org/show_bug.cgi?id=66605).
  base::ReplaceChars(suffix, " ", "_", &suffix);
  std::string glob = prefix + "*" + suffix + ".desktop";

  base::FileEnumerator files(directory, false, base::FileEnumerator::FILES,
                             glob);
  base::FilePath shortcut_file = files.Next();
  std::vector<base::FilePath> shortcut_paths;
  while (!shortcut_file.empty()) {
    shortcut_paths.push_back(shortcut_file.BaseName());
    shortcut_file = files.Next();
  }
  return shortcut_paths;
}

std::string GetDesktopFileContents(
    const base::FilePath& chrome_exe_path,
    const std::string& app_name,
    const GURL& url,
    const std::string& extension_id,
    const base::string16& title,
    const std::string& icon_name,
    const base::FilePath& profile_path,
    bool no_display) {
  CommandLine cmd_line = ShellIntegration::CommandLineArgsForLauncher(
      url, extension_id, profile_path);
  cmd_line.SetProgram(chrome_exe_path);
  return GetDesktopFileContentsForCommand(cmd_line, app_name, url, title,
                                          icon_name, no_display);
}

std::string GetDesktopFileContentsForCommand(
    const CommandLine& command_line,
    const std::string& app_name,
    const GURL& url,
    const base::string16& title,
    const std::string& icon_name,
    bool no_display) {
  // Although not required by the spec, Nautilus on Ubuntu Karmic creates its
  // launchers with an xdg-open shebang. Follow that convention.
  std::string output_buffer = std::string(kXdgOpenShebang) + "\n";

  // See http://standards.freedesktop.org/desktop-entry-spec/latest/
  GKeyFile* key_file = g_key_file_new();

  // Set keys with fixed values.
  g_key_file_set_string(key_file, kDesktopEntry, "Version", "1.0");
  g_key_file_set_string(key_file, kDesktopEntry, "Terminal", "false");
  g_key_file_set_string(key_file, kDesktopEntry, "Type", "Application");

  // Set the "Name" key.
  std::string final_title = base::UTF16ToUTF8(title);
  // Make sure no endline characters can slip in and possibly introduce
  // additional lines (like Exec, which makes it a security risk). Also
  // use the URL as a default when the title is empty.
  if (final_title.empty() ||
      final_title.find("\n") != std::string::npos ||
      final_title.find("\r") != std::string::npos) {
    final_title = url.spec();
  }
  g_key_file_set_string(key_file, kDesktopEntry, "Name", final_title.c_str());

  // Set the "Exec" key.
  std::string final_path = QuoteCommandLineForDesktopFileExec(command_line);
  g_key_file_set_string(key_file, kDesktopEntry, "Exec", final_path.c_str());

  // Set the "Icon" key.
  if (!icon_name.empty()) {
    g_key_file_set_string(key_file, kDesktopEntry, "Icon", icon_name.c_str());
  } else {
    g_key_file_set_string(key_file, kDesktopEntry, "Icon",
                          GetIconName().c_str());
  }

  // Set the "NoDisplay" key.
  if (no_display)
    g_key_file_set_string(key_file, kDesktopEntry, "NoDisplay", "true");

  std::string wmclass = web_app::GetWMClassFromAppName(app_name);
  g_key_file_set_string(key_file, kDesktopEntry, "StartupWMClass",
                        wmclass.c_str());

  gsize length = 0;
  gchar* data_dump = g_key_file_to_data(key_file, &length, NULL);
  if (data_dump) {
    // If strlen(data_dump[0]) == 0, this check will fail.
    if (data_dump[0] == '\n') {
      // Older versions of glib produce a leading newline. If this is the case,
      // remove it to avoid double-newline after the shebang.
      output_buffer += (data_dump + 1);
    } else {
      output_buffer += data_dump;
    }
    g_free(data_dump);
  }

  g_key_file_free(key_file);
  return output_buffer;
}

std::string GetDirectoryFileContents(const base::string16& title,
                                     const std::string& icon_name) {
  // See http://standards.freedesktop.org/desktop-entry-spec/latest/
  GKeyFile* key_file = g_key_file_new();

  g_key_file_set_string(key_file, kDesktopEntry, "Version", "1.0");
  g_key_file_set_string(key_file, kDesktopEntry, "Type", "Directory");
  std::string final_title = base::UTF16ToUTF8(title);
  g_key_file_set_string(key_file, kDesktopEntry, "Name", final_title.c_str());
  if (!icon_name.empty()) {
    g_key_file_set_string(key_file, kDesktopEntry, "Icon", icon_name.c_str());
  } else {
    g_key_file_set_string(key_file, kDesktopEntry, "Icon",
                          GetIconName().c_str());
  }

  gsize length = 0;
  gchar* data_dump = g_key_file_to_data(key_file, &length, NULL);
  std::string output_buffer;
  if (data_dump) {
    // If strlen(data_dump[0]) == 0, this check will fail.
    if (data_dump[0] == '\n') {
      // Older versions of glib produce a leading newline. If this is the case,
      // remove it to avoid double-newline after the shebang.
      output_buffer += (data_dump + 1);
    } else {
      output_buffer += data_dump;
    }
    g_free(data_dump);
  }

  g_key_file_free(key_file);
  return output_buffer;
}

bool CreateDesktopShortcut(
    const ShellIntegration::ShortcutInfo& shortcut_info,
    const ShellIntegration::ShortcutLocations& creation_locations) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  base::FilePath shortcut_filename;
  if (!shortcut_info.extension_id.empty()) {
    shortcut_filename = GetExtensionShortcutFilename(
        shortcut_info.profile_path, shortcut_info.extension_id);
    // For extensions we do not want duplicate shortcuts. So, delete any that
    // already exist and replace them.
    if (creation_locations.on_desktop)
      DeleteShortcutOnDesktop(shortcut_filename);
    // The 'applications_menu_location' and 'hidden' locations are actually the
    // same place ('applications').
    if (creation_locations.applications_menu_location !=
            ShellIntegration::APP_MENU_LOCATION_NONE ||
        creation_locations.hidden)
      DeleteShortcutInApplicationsMenu(shortcut_filename, base::FilePath());
  } else {
    shortcut_filename = GetWebShortcutFilename(shortcut_info.url);
  }
  if (shortcut_filename.empty())
    return false;

  std::string icon_name =
      CreateShortcutIcon(shortcut_info.favicon, shortcut_filename);

  std::string app_name =
      web_app::GenerateApplicationNameFromInfo(shortcut_info);

  bool success = true;

  base::FilePath chrome_exe_path = GetChromeExePath();
  if (chrome_exe_path.empty()) {
    LOG(WARNING) << "Could not get executable path.";
    return false;
  }

  if (creation_locations.on_desktop) {
    std::string contents = ShellIntegrationLinux::GetDesktopFileContents(
        chrome_exe_path,
        app_name,
        shortcut_info.url,
        shortcut_info.extension_id,
        shortcut_info.title,
        icon_name,
        shortcut_info.profile_path,
        false);
    success = CreateShortcutOnDesktop(shortcut_filename, contents);
  }

  if (creation_locations.applications_menu_location !=
          ShellIntegration::APP_MENU_LOCATION_NONE ||
      creation_locations.hidden) {
    base::FilePath directory_filename;
    std::string directory_contents;
    switch (creation_locations.applications_menu_location) {
      case ShellIntegration::APP_MENU_LOCATION_NONE:
      case ShellIntegration::APP_MENU_LOCATION_ROOT:
        break;
      case ShellIntegration::APP_MENU_LOCATION_SUBDIR_CHROMEAPPS:
        directory_filename = base::FilePath(kDirectoryFilename);
        directory_contents = ShellIntegrationLinux::GetDirectoryFileContents(
            ShellIntegration::GetAppShortcutsSubdirName(), "");
        break;
      default:
        NOTREACHED();
        break;
    }
    // Set NoDisplay=true if hidden but not in the applications menu. This will
    // hide the application from user-facing menus.
    std::string contents = ShellIntegrationLinux::GetDesktopFileContents(
        chrome_exe_path,
        app_name,
        shortcut_info.url,
        shortcut_info.extension_id,
        shortcut_info.title,
        icon_name,
        shortcut_info.profile_path,
        creation_locations.applications_menu_location ==
            ShellIntegration::APP_MENU_LOCATION_NONE);
    success = CreateShortcutInApplicationsMenu(
        shortcut_filename, contents, directory_filename, directory_contents) &&
        success;
  }

  return success;
}

bool CreateAppListDesktopShortcut(
    const std::string& wm_class,
    const std::string& title) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  base::FilePath desktop_name(kAppListDesktopName);
  base::FilePath shortcut_filename = desktop_name.AddExtension("desktop");

  // We do not want duplicate shortcuts. Delete any that already exist and
  // replace them.
  DeleteShortcutInApplicationsMenu(shortcut_filename, base::FilePath());

  base::FilePath chrome_exe_path = GetChromeExePath();
  if (chrome_exe_path.empty()) {
    LOG(WARNING) << "Could not get executable path.";
    return false;
  }

  gfx::ImageFamily icon_images;
  ResourceBundle& resource_bundle = ResourceBundle::GetSharedInstance();
  icon_images.Add(*resource_bundle.GetImageSkiaNamed(IDR_APP_LIST_16));
  icon_images.Add(*resource_bundle.GetImageSkiaNamed(IDR_APP_LIST_32));
  icon_images.Add(*resource_bundle.GetImageSkiaNamed(IDR_APP_LIST_48));
  icon_images.Add(*resource_bundle.GetImageSkiaNamed(IDR_APP_LIST_256));
  std::string icon_name = CreateShortcutIcon(icon_images, desktop_name);

  CommandLine command_line(chrome_exe_path);
  command_line.AppendSwitch(switches::kShowAppList);
  std::string contents = GetDesktopFileContentsForCommand(
      command_line, wm_class, GURL(), base::UTF8ToUTF16(title), icon_name,
      false);
  return CreateShortcutInApplicationsMenu(
      shortcut_filename, contents, base::FilePath(), "");
}

void DeleteDesktopShortcuts(const base::FilePath& profile_path,
                            const std::string& extension_id) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  base::FilePath shortcut_filename = GetExtensionShortcutFilename(
      profile_path, extension_id);
  DCHECK(!shortcut_filename.empty());

  DeleteShortcutOnDesktop(shortcut_filename);
  // Delete shortcuts from |kDirectoryFilename|.
  // Note that it is possible that shortcuts were not created in the Chrome Apps
  // directory. It doesn't matter: this will still delete the shortcut even if
  // it isn't in the directory.
  DeleteShortcutInApplicationsMenu(shortcut_filename,
                                   base::FilePath(kDirectoryFilename));
}

void DeleteAllDesktopShortcuts(const base::FilePath& profile_path) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  scoped_ptr<base::Environment> env(base::Environment::Create());

  // Delete shortcuts from Desktop.
  base::FilePath desktop_path;
  if (PathService::Get(base::DIR_USER_DESKTOP, &desktop_path)) {
    std::vector<base::FilePath> shortcut_filenames_desktop =
        GetExistingProfileShortcutFilenames(profile_path, desktop_path);
    for (std::vector<base::FilePath>::const_iterator it =
         shortcut_filenames_desktop.begin();
         it != shortcut_filenames_desktop.end(); ++it) {
      DeleteShortcutOnDesktop(*it);
    }
  }

  // Delete shortcuts from |kDirectoryFilename|.
  base::FilePath applications_menu;
  if (GetDataWriteLocation(env.get(), &applications_menu)) {
    applications_menu = applications_menu.AppendASCII("applications");
    std::vector<base::FilePath> shortcut_filenames_app_menu =
        GetExistingProfileShortcutFilenames(profile_path, applications_menu);
    for (std::vector<base::FilePath>::const_iterator it =
         shortcut_filenames_app_menu.begin();
         it != shortcut_filenames_app_menu.end(); ++it) {
      DeleteShortcutInApplicationsMenu(*it,
                                       base::FilePath(kDirectoryFilename));
    }
  }
}

}  // namespace ShellIntegrationLinux