Bug 1161020: Added clean interface to |UnixSocketConnector|, r=kmachulis

The current interface of |UnixSocketConnector| doesn't follow any design
and is not easily understandable.

This patch adds a new interface to the class. The new interface provides
a method for each of the following operations:

  * converting an address to a human-readable string,
  * creating a listening socket,
  * creating a stream socket, and
  * accepting a stream socket from a listening socket.

All arguments are stored in the connector class, so that connect and
listen methods of the socket classes don't require protocol-specific
arguments. All socket parameters are set within the connector class,
so each connector class can now select parameters individually.

ipc/unixsocket/UnixSocketConnector.cpp

@@ -5,12 +5,54 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "UnixSocketConnector.h"
+#include "nsISupportsImpl.h" // For MOZ_COUNT_CTOR, MOZ_COUNT_DTOR
 
 namespace mozilla {
 namespace ipc {
 
+UnixSocketConnector::UnixSocketConnector()
+{
+  MOZ_COUNT_CTOR(UnixSocketConnector);
+}
+
 UnixSocketConnector::~UnixSocketConnector()
-{ }
+{
+  MOZ_COUNT_DTOR(UnixSocketConnector);
+}
+
+nsresult
+UnixSocketConnector::ConvertAddressToString(const struct sockaddr& aAddress,
+                                            socklen_t aAddressLength,
+                                            nsACString& aAddressString)
+{
+  MOZ_CRASH("|UnixSocketConnector| does not convert addresses to strings.");
+  return NS_ERROR_ABORT;
+}
+
+nsresult
+UnixSocketConnector::CreateListenSocket(struct sockaddr* aAddress,
+                                        socklen_t* aAddressLength,
+                                        int& aListenFd)
+{
+  MOZ_CRASH("|UnixSocketConnector| does not support listening sockets.");
+}
+
+nsresult
+UnixSocketConnector::AcceptStreamSocket(int aListenFd,
+                                        struct sockaddr* aAddress,
+                                        socklen_t* aAddressLen,
+                                        int& aStreamFd)
+{
+  MOZ_CRASH("|UnixSocketConnector| does not support accepting stream sockets.");
+}
+
+nsresult
+UnixSocketConnector::CreateStreamSocket(struct sockaddr* aAddress,
+                                        socklen_t* aAddressLength,
+                                        int& aStreamFd)
+{
+  MOZ_CRASH("|UnixSocketConnector| does not support creating stream sockets.");
+}
 
 }
 }

ipc/unixsocket/UnixSocketConnector.h

@@ -7,6 +7,7 @@
 #ifndef mozilla_ipc_unixsocketconnector_h
 #define mozilla_ipc_unixsocketconnector_h
 
+#include <sys/socket.h>
 #include "mozilla/ipc/UnixSocketWatcher.h"
 #include "nsString.h"
 
@@ -16,7 +17,7 @@ namespace ipc {
 /**
  * |UnixSocketConnector| defines the socket creation and connection/listening
  * functions for |UnixSocketConsumer|, et al. Due to the fact that socket setup
- * can vary between protocols (unix sockets, tcp sockets, bluetooth sockets, etc),
+ * can vary between protocols (Unix sockets, TCP sockets, Bluetooth sockets, etc),
  * this allows the user to create whatever connection mechanism they need while
  * still depending on libevent for non-blocking communication handling.
  */
@@ -25,9 +26,61 @@ class UnixSocketConnector
 public:
   virtual ~UnixSocketConnector();
 
+  /**
+   * Converts an address to a human-readable string.
+   *
+   * @param aAddress A socket address
+   * @param aAddressLength The number of valid bytes in |aAddress|
+   * @param[out] aAddressString The resulting string
+   * @return NS_OK on success, or an XPCOM error code otherwise.
+   */
+  virtual nsresult ConvertAddressToString(const struct sockaddr& aAddress,
+                                          socklen_t aAddressLength,
+                                          nsACString& aAddressString);
+
+  /**
+   * Creates a listening socket. I/O thread only.
+   *
+   * @param[out] aAddress The listening socket's address
+   * @param[out] aAddressLength The number of valid bytes in |aAddress|
+   * @param[out] aListenFd The socket's file descriptor
+   * @return NS_OK on success, or an XPCOM error code otherwise.
+   */
+  virtual nsresult CreateListenSocket(struct sockaddr* aAddress,
+                                      socklen_t* aAddressLength,
+                                      int& aListenFd);
+
+  /**
+   * Accepts a stream socket from a listening socket. I/O thread only.
+   *
+   * @param aListenFd The listening socket
+   * @param[out] aAddress Returns the stream socket's address
+   * @param[out] aAddressLength Returns the number of valid bytes in |aAddress|
+   * @param[out] aStreamFd The stream socket's file descriptor
+   * @return NS_OK on success, or an XPCOM error code otherwise.
+   */
+  virtual nsresult AcceptStreamSocket(int aListenFd,
+                                      struct sockaddr* aAddress,
+                                      socklen_t* aAddressLen,
+                                      int& aStreamFd);
+
+  /**
+   * Creates a stream socket. I/O thread only.
+   *
+   * @param[in|out] aAddress The stream socket's address
+   * @param[in|out] aAddressLength The number of valid bytes in |aAddress|
+   * @param[out] aStreamFd The socket's file descriptor
+   * @return NS_OK on success, or an XPCOM error code otherwise.
+   */
+  virtual nsresult CreateStreamSocket(struct sockaddr* aAddress,
+                                      socklen_t* aAddressLength,
+                                      int& aStreamFd);
+
   /**
    * Establishs a file descriptor for a socket.
    *
+   * @deprecated
+   *
    * @return File descriptor for socket
    */
   virtual int Create() = 0;
@@ -37,6 +90,8 @@ public:
    * sockaddr struct, this function is defined by subclasses and fills in the
    * structure as needed for whatever connection it is trying to build
    *
+   * @deprecated
+   *
    * @param aIsServer True is we are acting as a server socket
    * @param aAddrSize Size of the struct
    * @param aAddr Struct to fill
@@ -62,6 +117,8 @@ public:
   /**
    * Perform socket setup for socket created by ListenSocket(), after listen().
    *
+   * @deprecated
+   *
    * @param aFd File descriptor for opened socket
    *
    * @return true is successful, false otherwise
@@ -72,11 +129,16 @@ public:
    * Get address of socket we're currently connected to. Return null string if
    * not connected.
    *
+   * @deprecated
+   *
    * @param aAddr Address struct
    * @param aAddrStr String to store address to
    */
   virtual void GetSocketAddr(const sockaddr_any& aAddr,
                              nsAString& aAddrStr) = 0;
+
+protected:
+  UnixSocketConnector();
 };
 
 }