Linux: split GNOME Keyring integration into a separate process.

chrome/browser/password_manager/proxy/keyring_loader.h

+// Copyright (c) 2011 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.
+
+#ifndef CHROME_BROWSER_PASSWORD_MANAGER_PROXY_KEYRING_LOADER_H_
+#define CHROME_BROWSER_PASSWORD_MANAGER_PROXY_KEYRING_LOADER_H_
+#pragma once
+
+#include <gnome-keyring.h>
+
+#include <string>
+
+// Many of the gnome_keyring_* functions use variable arguments, which makes
+// them difficult if not impossible to truly wrap in C/C++. Therefore, we use
+// appropriately-typed function pointers and scoping to make the fact that we
+// might be dynamically loading the library almost invisible. Classes that
+// inherit from GnomeKeyringLoader will use its versions of the gnome_keyring_*
+// functions. Note that it has only static fields.
+class GnomeKeyringLoader {
+ protected:
+  static bool LoadGnomeKeyring();
+
+// Call a given parameter with the name of each function we use from GNOME
+// Keyring. Make sure to adjust the unit test if you change these.
+#define GNOME_KEYRING_FOR_EACH_FUNC(F)          \
+  F(is_available)                               \
+  F(store_password)                             \
+  F(delete_password)                            \
+  F(find_itemsv)                                \
+  F(result_to_message)
+
+// Declare the actual function pointers that we'll use in client code.
+#define GNOME_KEYRING_DECLARE_POINTER(name) \
+    static typeof(&::gnome_keyring_##name) gnome_keyring_##name;
+  GNOME_KEYRING_FOR_EACH_FUNC(GNOME_KEYRING_DECLARE_POINTER)
+#undef GNOME_KEYRING_DECLARE_POINTER
+
+  // Set to true if LoadGnomeKeyring() has already succeeded.
+  static bool keyring_loaded;
+
+ private:
+#if defined(DLOPEN_GNOME_KEYRING)
+  struct FunctionInfo {
+    const char* name;
+    void** pointer;
+  };
+
+  // Make it easy to initialize the function pointers in LoadGnomeKeyring().
+  static const FunctionInfo functions[];
+#endif  // defined(DLOPEN_GNOME_KEYRING)
+};
+
+#endif  // CHROME_BROWSER_PASSWORD_MANAGER_PROXY_KEYRING_LOADER_H_