Linux: Support the --class argument (Reland)

chrome/browser/shell_integration_linux.cc

 // 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 <stddef.h>
 
 #include <memory>
@@ skipping 190 matching lines @@
     return UNKNOWN_DEFAULT;
   }
 
   // Allow any reply that starts with "yes".
   return base::StartsWith(reply, "yes", base::CompareCase::SENSITIVE)
              ? IS_DEFAULT
              : NOT_DEFAULT;
 #endif
 }
 
+// https://wiki.gnome.org/Projects/GnomeShell/ApplicationBased
+// The WM_CLASS property should be set to the same as the *.desktop file without
+// the .desktop extension.  We cannot simply use argv[0] in this case, because
+// on the stable channel, the executable name is google-chrome-stable, but the
+// desktop file is google-chrome.desktop.
+std::string GetDesktopBaseName(const std::string& desktop_file_name) {
+  static const char kDesktopExtension[] = ".desktop";
+  if (base::EndsWith(desktop_file_name, kDesktopExtension,
+                     base::CompareCase::SENSITIVE)) {
+    return desktop_file_name.substr(
+        0, desktop_file_name.length() - strlen(kDesktopExtension));
+  }
+  return desktop_file_name;
+}
+
 }  // namespace
 
 bool SetAsDefaultBrowser() {
   return SetDefaultWebClient(std::string());
 }
 
 bool SetAsDefaultProtocolClient(const std::string& protocol) {
   return SetDefaultWebClient(protocol);
 }
 
@@ skipping 348 matching lines @@
       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;
 }
 
+namespace internal {
+
+std::string GetProgramClassName(const base::CommandLine& command_line,
+                                const std::string& desktop_file_name) {
+  std::string class_name =
+      shell_integration::GetDesktopBaseName(desktop_file_name);
+  std::string user_data_dir =
+      command_line.GetSwitchValueNative(switches::kUserDataDir);
+  // If the user launches with e.g. --user-data-dir=/tmp/my-user-data, set the
+  // class name to "Chrome (/tmp/my-user-data)".  The class name will show up in
+  // the alt-tab list in gnome-shell if you're running a binary that doesn't
+  // have a matching .desktop file.
+  return user_data_dir.empty()
+             ? class_name
+             : class_name + " (" + user_data_dir + ")";
+}
+
+std::string GetProgramClassClass(const base::CommandLine& command_line,
+                                 const std::string& desktop_file_name) {
+  if (command_line.HasSwitch(switches::kWmClass))

[Lei Zhang, 2016/07/29 00:41:43]

Do we really want to return "" if the user passed in "--class" ?

[Tom (Use chromium acct), 2016/07/29 18:52:34]

The empty string is a valid class, but if I run gedit, for example, "gedit
--class" is an error, "gedit --class=" is a class with the empty string, and
'--class=""' is also the empty string.

The only inconsistency here is that Chrome will accept "chrome --class" without
error.  Is there any way to replicate this behavior?

[Lei Zhang, 2016/07/29 18:58:20]

So it is. Nevermind then.

+    return command_line.GetSwitchValueASCII(switches::kWmClass);
+  std::string class_class =
+      shell_integration::GetDesktopBaseName(desktop_file_name);
+  if (!class_class.empty()) {
+    // Capitalize the first character like gtk does.
+    class_class[0] = base::ToUpperASCII(class_class[0]);
+  }
+  return class_class;
+}
+
+}  // namespace internal
+
 std::string GetProgramClassName() {
   std::unique_ptr<base::Environment> env(base::Environment::Create());
-  std::string desktop_file(GetDesktopName(env.get()));
-  std::size_t last = desktop_file.find(".desktop");
-  if (last != std::string::npos)
-    return desktop_file.substr(0, last);
-  return desktop_file;
+  return internal::GetProgramClassName(*base::CommandLine::ForCurrentProcess(),
+                                       GetDesktopName(env.get()));
+}
+
+std::string GetProgramClassClass() {
+  std::unique_ptr<base::Environment> env(base::Environment::Create());
+  return internal::GetProgramClassClass(*base::CommandLine::ForCurrentProcess(),
+                                        GetDesktopName(env.get()));
 }
 
 std::string GetDesktopName(base::Environment* env) {
 #if defined(GOOGLE_CHROME_BUILD)
   version_info::Channel product_channel(chrome::GetChannel());
   switch (product_channel) {
     case version_info::Channel::DEV:
       return "google-chrome-unstable.desktop";
     case version_info::Channel::BETA:
       return "google-chrome-beta.desktop";
@@ skipping 460 matching lines @@
   base::FilePath applications_menu = GetDataWriteLocation(env.get());
   applications_menu = applications_menu.AppendASCII("applications");
   std::vector<base::FilePath> shortcut_filenames_app_menu =
       GetExistingProfileShortcutFilenames(profile_path, applications_menu);
   for (const auto& menu : shortcut_filenames_app_menu) {
     DeleteShortcutInApplicationsMenu(menu, base::FilePath(kDirectoryFilename));
   }
 }
 
 }  // namespace shell_integration_linux