Add doxygen documentation to functions in xcbext.h

Signed-off-by: Uli Schlachter <psychon@znc.in>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

src/xcbext.h

@@ -58,11 +58,56 @@ enum xcb_send_request_flags_t {
     XCB_REQUEST_REPLY_FDS = 1 << 3
 };
 
+/**
+ * @brief Send a request to the server.
+ * @param c: The connection to the X server.
+ * @param flags: A combination of flags from the xcb_send_request_flags_t enumeration.
+ * @param vector: Data to send; must have two iovecs before start for internal use.
+ * @param request: Information about the request to be sent.
+ * @return The request's sequence number on success, 0 otherwise.
+ *
+ * This function sends a new request to the X server. The data of the request is
+ * given as an array of @c iovecs in the @p vector argument. The length of that
+ * array and the neccessary management information are given in the @p request
+ * argument.
+ *
+ * When this function returns, the request might or might not be sent already.
+ * Use xcb_flush() to make sure that it really was sent.
+ *
+ * Please note that this function is not the prefered way for sending requests.
+ * It's better to use the generated wrapper functions.
+ *
+ * Please note that xcb might use index -1 and -2 of the @p vector array internally,
+ * so they must be valid!
+ */
 unsigned int xcb_send_request(xcb_connection_t *c, int flags, struct iovec *vector, const xcb_protocol_request_t *request);
 
+/**
+ * @brief Send a file descriptor to the server in the next call to xcb_send_request.
+ * @param c: The connection to the X server.
+ * @param fd: The file descriptor to send.
+ *
+ * After this function returns, the file descriptor given is owned by xcb and
+ * will be closed eventually.
+ *
+ * FIXME: How the heck is this supposed to work in a thread-safe way? There is a
+ * race between two threads doing xcb_send_fd(); xcb_send_request(); at the same
+ * time.
+ */
 void xcb_send_fd(xcb_connection_t *c, int fd);
 
-/* xcb_take_socket allows external code to ask XCB for permission to
+/**
+ * @brief Take over the write side of the socket
+ * @param c: The connection to the X server.
+ * @param return_socket: Callback function that will be called when xcb wants
+ *                        to use the socket again.
+ * @param closure: Argument to the callback function.
+ * @param flags: A combination of flags from the xcb_send_request_flags_t enumeration.
+ * @param sent: Location to the sequence number of the last sequence request.
+ *              Must not be NULL.
+ * @return 1 on success, else 0.
+ *
+ * xcb_take_socket allows external code to ask XCB for permission to
  * take over the write side of the socket and send raw data with
  * xcb_writev. xcb_take_socket provides the sequence number of the last
  * request XCB sent. The caller of xcb_take_socket must supply a
@@ -71,10 +116,24 @@ void xcb_send_fd(xcb_connection_t *c, int fd);
  * external socket owner and flushes any output queues if appropriate.
  * If you are sending requests which won't cause a reply, please note the
  * comment for xcb_writev which explains some sequence number wrap issues.
- * */
+ *
+ * All replies that are generated while the socket is owned externally have
+ * @p flags applied to them. For example, use XCB_REQUEST_CHECK if you don't
+ * want errors to go to xcb's normal error handling, but instead having to be
+ * picked up via xcb_wait_for_reply(), xcb_poll_for_reply() or
+ * xcb_request_check().
+ */
 int xcb_take_socket(xcb_connection_t *c, void (*return_socket)(void *closure), void *closure, int flags, uint64_t *sent);
 
-/* You must own the write-side of the socket (you've called
+/**
+ * @brief Send raw data to the X server.
+ * @param c: The connection to the X server.
+ * @param vector: Array of data to be sent.
+ * @param count: Number of entries in @p vector.
+ * @param requests: Number of requests that are being sent.
+ * @return 1 on success, else 0.
+ *
+ * You must own the write-side of the socket (you've called
  * xcb_take_socket, and haven't returned from return_socket yet) to call
  * xcb_writev. Also, the iovec must have at least 1 byte of data in it.
  * You have to make sure that xcb can detect sequence number wraps correctly.
@@ -83,20 +142,60 @@ int xcb_take_socket(xcb_connection_t *c, void (*return_socket)(void *closure), v
  * requests without a reply, you have to insert a request which will cause a
  * reply. You can again use GetInputFocus for this. You do not have to wait for
  * any of the GetInputFocus replies, but can instead handle them via
- * xcb_discard_reply(). */
+ * xcb_discard_reply().
+ */
 int xcb_writev(xcb_connection_t *c, struct iovec *vector, int count, uint64_t requests);
 
 
 /* xcb_in.c */
 
+/**
+ * @brief Wait for the reply of a given request.
+ * @param c: The connection to the X server.
+ * @param request: Sequence number of the request as returned by xcb_send_request().
+ * @param e: Location to store errors in, or NULL. Ignored for unchecked requests.
+ *
+ * Returns the reply to the given request or returns null in the event of
+ * errors. Blocks until the reply or error for the request arrives, or an I/O
+ * error occurs.
+ */
 void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e);
+
+/**
+ * @brief Poll for the reply of a given request.
+ * @param c: The connection to the X server.
+ * @param request: Sequence number of the request as returned by xcb_send_request().
+ * @param reply: Location to store the reply in, must not be NULL.
+ * @param e: Location to store errors in, or NULL. Ignored for unchecked requests.
+ * @return 1 when the reply to the request was returned, else 0.
+ *
+ * Checks if the reply to the given request already received. Does not block.
+ */
 int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error);
+
+/**
+ * @brief Don't use this, only needed by the generated code.
+ * @param c: The connection to the X server.
+ * @param reply: A reply that was received from the server
+ * @param replylen: The size of the reply.
+ * @return Pointer to the location where received file descriptors are stored.
+ */
 int *xcb_get_reply_fds(xcb_connection_t *c, void *reply, size_t replylen);
 
 
 /* xcb_util.c */
 
+/**
+ * @param mask: The mask to check
+ * @return The number of set bits in the mask
+ */
 int xcb_popcount(uint32_t mask);
+
+/**
+ * @param list: The base of an array
+ * @param len: The length of the array
+ * @return The sum of all entries in the array.
+ */
 int xcb_sumof(uint8_t *list, int len);
 
 #ifdef __cplusplus