Linux: split GNOME Keyring integration into a separate process.

chrome/browser/password_manager/keyring_proxy/keyring_proxy_client.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_KEYRING_PROXY_KEYRING_PROXY_CLIENT_H_
+#define CHROME_BROWSER_PASSWORD_MANAGER_KEYRING_PROXY_KEYRING_PROXY_CLIENT_H_
+#pragma once
+
+#include <gnome-keyring.h>
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "base/synchronization/waitable_event.h"
+
+namespace webkit_glue {
+struct PasswordForm;
+}
+
+namespace keyring_proxy {
+
+// Used internally by KeyringProxyClient to watch the file descriptor for data
+// to read. Done in a separate class so it can be refcounted and shut down
+// safely on the file thread after pending callbacks are done.
+class KeyringProxyFDWatcher;
+
+class KeyringProxyClient {
+ public:
+  // This is the name of the binary for the proxy itself.
+  static const char kProxyBinary[];
+
+  // Save some typing with convenient short types for password forms.
+  typedef webkit_glue::PasswordForm PasswordForm;
+  typedef std::vector<PasswordForm*> PasswordFormList;
+
+  // Every request to the proxy has a context, and internally also an ID.
+  struct RequestContext {
+    base::WaitableEvent event;
+    GnomeKeyringResult result_code;
+    PasswordFormList* result_list;  // Not used for AddLogin() or RemoveLogin().
+
+    RequestContext()
+        : event(false, false), result_code(GNOME_KEYRING_RESULT_CANCELLED),
+          result_list(NULL) {}
+    explicit RequestContext(PasswordFormList* list)
+        : event(false, false), result_code(GNOME_KEYRING_RESULT_CANCELLED),
+          result_list(list) {}
+  };
+
+  // The client is constructed and destructed on the UI thread.
+  KeyringProxyClient();
+  ~KeyringProxyClient();
+
+  // Starts a keyring proxy process. Returns true on fork() success; the process
+  // itself may still fail to start or fail later. Use connected() to check it.
+  // Safe to call on the UI thread after instantiation, but if called again to
+  // reconnect later, should be called on the DB thread.
+  bool Connect();
+
+  // Returns true if the keyring proxy is still connected as far as we know.
+  bool connected() const { return !!fd_watcher_.get(); }
+
+  // These are safe to call on the DB thread. The request is complete when the
+  // waitable event in the provided request context becomes ready. The actual
+  // callbacks that happen when data is received from the proxy will happen on
+  // the file thread, where they will signal the waitable events. This is done
+  // because we want to parallelize multiple requests, but the password store
+  // APIs on the DB thread are synchronous and so must wait for the replies.
+  void AddLogin(const PasswordForm& form,
+                const std::string& app_string,
+                RequestContext* context);
+  void AddLoginSearch(const PasswordForm& form,
+                      const std::string& app_string,
+                      RequestContext* context);
+  void UpdateLoginSearch(const PasswordForm& form,
+                         const std::string& app_string,
+                         RequestContext* context);
+  void RemoveLogin(const PasswordForm& form,
+                   const std::string& app_string,
+                   RequestContext* context);
+  void GetLogins(const PasswordForm& form,
+                 const std::string& app_string,
+                 RequestContext* context);
+  void GetLoginsList(bool blacklisted_by_user,
+                     const std::string& app_string,
+                     RequestContext* context);
+  void GetAllLogins(const std::string& app_string,
+                    RequestContext* context);
+
+  // Launches the keyring proxy and returns the IPC file descriptor to it.
+  static int LaunchKeyringProxy();
+
+ protected:
+  // This is the type of the messages actually exchanged with the proxy.
+  typedef std::vector<std::string> ProxyMessage;
+
+  // Connects to the given file descriptor instead of launching the proxy.
+  // Will still close it, but will only listen for reads if requested.
+  void ConnectForTesting(int fd, bool watch_for_reads);
+
+  // Cancel all outstanding requests and unblock waiters. Must already hold
+  // |request_lock_| to call CancelAllRequests(). Protected for testing.
+  void CancelAllRequests();
+
+  // These are called by KeyringProxyFDWatcher on the file thread.
+  void HandleProxyReply(const ProxyMessage& reply);
+  void HandleProxyError(bool eof);
+
+ private:
+  friend class KeyringProxyFDWatcher;
+
+  // Must already hold |request_lock_| to call GetRequestId().
+  int GetRequestId();
+  // Send a request of type |type| and add an entry to |proxy_requests_| for it.
+  void SendRequest(
+      char type, const ProxyMessage& request, RequestContext* context);
+
+  // Cancel a single request context, unblocking the waiter.
+  void CancelRequest(RequestContext* context);
+
+  scoped_refptr<KeyringProxyFDWatcher> fd_watcher_;
+
+  // The next proxy request ID to try.
+  int next_request_id_;
+
+  // A map from proxy request IDs to proxy requests. Guarded by |request_lock_|.
+  std::map<int, RequestContext*> proxy_requests_;
+
+  // Guards |proxy_requests_| since it is accessed on the DB and file threads.
+  base::Lock request_lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(KeyringProxyClient);
+};
+
+}  // namespace keyring_proxy
+
+#endif  // CHROME_BROWSER_PASSWORD_MANAGER_KEYRING_PROXY_KEYRING_PROXY_CLIENT_H_