| /* |
| This file is part of libmicrospdy |
| Copyright Copyright (C) 2012 Andrey Uzunov |
| |
| This program is free software: you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation, either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| /** |
| * @file session.h |
| * @brief TCP connection/SPDY session handling |
| * @author Andrey Uzunov |
| */ |
| |
| #ifndef SESSION_H |
| #define SESSION_H |
| |
| #include "platform.h" |
| #include "structures.h" |
| |
| /** |
| * Called by the daemon when the socket for the session has available |
| * data to be read. Reads data from the TLS socket and puts it to the |
| * session's read buffer. The latte |
| * |
| * @param session SPDY_Session for which data will be read. |
| * @return SPDY_YES if something was read or session's status was |
| * changed. It is possible that error occurred but was handled |
| * and the status was therefore changed. |
| * SPDY_NO if nothing happened, e.g. the subsystem wants read/ |
| * write to be called again. |
| */ |
| int |
| SPDYF_session_read (struct SPDY_Session *session); |
| |
| |
| /** |
| * Called by the daemon when the socket for the session is ready for some |
| * data to be written to it. For one or more objects on the response |
| * queue tries to fill in the write buffer, based on the frame on the |
| * queue, and to write data to the TLS socket. |
| * |
| * @param session SPDY_Session for which data will be written. |
| * @param only_one_frame when true, the function will write at most one |
| * SPDY frame to the underlying IO subsystem; |
| * when false, the function will write up to |
| * session->max_num_frames SPDY frames |
| * @return SPDY_YES if the session's internal writing state has changed: |
| * something was written and/or session's status was |
| * changed and/or response callback was called but did not provide |
| * data. It is possible that error occurred but was handled |
| * and the status was therefore changed. |
| * SPDY_NO if nothing happened. However, it is possible that some |
| * frames were discarded within the call, e.g. frames belonging |
| * to a closed stream. |
| */ |
| int |
| SPDYF_session_write (struct SPDY_Session *session, |
| bool only_one_frame); |
| |
| |
| /** |
| * Called by the daemon on SPDY_run to handle the data in the read and write |
| * buffer of a session. Based on the state and the content of the read |
| * buffer new frames are received and interpreted, appropriate user |
| * callbacks are called and maybe something is put on the response queue |
| * ready to be handled by session_write. |
| * |
| * @param session SPDY_Session which will be handled. |
| * @return SPDY_YES if something from the read buffers was processed, |
| * session's status was changed and/or the session was closed. |
| * SPDY_NO if nothing happened, e.g. the session is in a state, |
| * not allowing processing read buffers. |
| */ |
| int |
| SPDYF_session_idle (struct SPDY_Session *session); |
| |
| |
| /** |
| * This function shutdowns the socket, moves the session structure to |
| * daemon's queue for sessions to be cleaned up. |
| * |
| * @param session SPDY_Session which will be handled. |
| */ |
| void |
| SPDYF_session_close (struct SPDY_Session *session); |
| |
| |
| /** |
| * Called to accept new TCP connection and create SPDY session. |
| * |
| * @param daemon SPDY_Daemon whose listening socket is used. |
| * @return SPDY_NO on any kind of error while accepting new TCP connection |
| * and initializing new SPDY_Session. |
| * SPDY_YES otherwise. |
| */ |
| int |
| SPDYF_session_accept(struct SPDY_Daemon *daemon); |
| |
| |
| /** |
| * Puts SPDYF_Response_Queue object on the queue to be sent to the |
| * client later. |
| * |
| * @param response_to_queue linked list of objects containing SPDY |
| * frame and data to be added to the queue |
| * @param session SPDY session for which the response is sent |
| * @param consider_priority if SPDY_NO, the list will be added to the |
| * end of the queue. |
| * If SPDY_YES, the response will be added after |
| * the last previously added response with priority of the |
| * request grater or equal to that of the current one. |
| * If -1, the object will be put at the head of the queue. |
| */ |
| void |
| SPDYF_queue_response (struct SPDYF_Response_Queue *response_to_queue, |
| struct SPDY_Session *session, |
| int consider_priority); |
| |
| |
| /** |
| * Cleans up the TSL context for the session, closes the TCP connection, |
| * cleans up any data pointed by members of the session structure |
| * (buffers, queue of responses, etc.) and frees the memory allocated by |
| * the session itself. |
| */ |
| void |
| SPDYF_session_destroy(struct SPDY_Session *session); |
| |
| |
| /** |
| * Prepares GOAWAY frame to tell the client to stop creating new streams. |
| * The session should be closed soon after this call. |
| * |
| * @param session SPDY session |
| * @param status code for the GOAWAY frame |
| * @param in_front whether or not to put the frame in front of everything |
| * on the response queue |
| * @return SPDY_NO on error (not enough memory) or |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_prepare_goaway (struct SPDY_Session *session, |
| enum SPDY_GOAWAY_STATUS status, |
| bool in_front); |
| |
| |
| /** |
| * Prepares RST_STREAM frame to terminate a stream. This frame may or |
| * not indicate an error. The frame will be put at the head of the queue. |
| * This means that frames for this stream which are still in the queue |
| * will be discarded soon. |
| * |
| * @param session SPDY session |
| * @param stream stream to terminate |
| * @param status code for the RST_STREAM frame |
| * @return SPDY_NO on memory error or |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_prepare_rst_stream (struct SPDY_Session *session, |
| struct SPDYF_Stream * stream, |
| enum SPDY_RST_STREAM_STATUS status); |
| |
| |
| /** |
| * Prepares WINDOW_UPDATE frame to tell the other party that more |
| * data can be sent on the stream. The frame will be put at the head of |
| * the queue. |
| * |
| * @param session SPDY session |
| * @param stream stream to which the changed window will apply |
| * @param delta_window_size how much the window grows |
| * @return SPDY_NO on memory error or |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_prepare_window_update (struct SPDY_Session *session, |
| struct SPDYF_Stream * stream, |
| int32_t delta_window_size); |
| |
| |
| /** |
| * Handler called by session_write to fill the write buffer according to |
| * the data frame waiting in the response queue. |
| * When response data is given by user callback, the lib does not know |
| * how many frames are needed. In such case this call produces |
| * another ResponseQueue object and puts it on the queue while the the |
| * user callback says that there will be more data. |
| * |
| * @return SPDY_NO on error (not enough memory or the user calback for |
| * providing response data did something wrong). If |
| * the error is unrecoverable the handler changes session's |
| * status. |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_handler_write_data (struct SPDY_Session *session); |
| |
| |
| /** |
| * Handler called by session_write to fill the write buffer based on the |
| * control frame (SYN_REPLY) waiting in the response queue. |
| * |
| * @param session SPDY session |
| * @return SPDY_NO on error (zlib state is broken; the session MUST be |
| * closed). If |
| * the error is unrecoverable the handler changes session's |
| * status. |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_handler_write_syn_reply (struct SPDY_Session *session); |
| |
| |
| /** |
| * Handler called by session_write to fill the write buffer based on the |
| * control frame (GOAWAY) waiting in the response queue. |
| * |
| * @param session SPDY session |
| * @return SPDY_NO on error (not enough memory; by specification the |
| * session must be closed |
| * soon, thus there is no need to handle the error) or |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_handler_write_goaway (struct SPDY_Session *session); |
| |
| |
| /** |
| * Handler called by session_write to fill the write buffer based on the |
| * control frame (RST_STREAM) waiting in the response queue. |
| * |
| * @param session SPDY session |
| * @return SPDY_NO on error (not enough memory). If |
| * the error is unrecoverable the handler changes session's |
| * status. |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_handler_write_rst_stream (struct SPDY_Session *session); |
| |
| |
| /** |
| * Handler called by session_write to fill the write buffer based on the |
| * control frame (WINDOW_UPDATE) waiting in the response queue. |
| * |
| * @param session SPDY session |
| * @return SPDY_NO on error (not enough memory). If |
| * the error is unrecoverable the handler changes session's |
| * status. |
| * SPDY_YES on success |
| */ |
| int |
| SPDYF_handler_write_window_update (struct SPDY_Session *session); |
| |
| |
| /** |
| * Carefully ignore the full size of frames which are not yet supported |
| * by the lib. |
| * TODO Ignoring frames containing compressed bodies means that the |
| * compress state will be corrupted on next received frame. According to |
| * the draft the lib SHOULD try to decompress data also in corrupted |
| * frames just to keep right compression state. |
| * |
| * @param session SPDY_Session whose read buffer is used. |
| */ |
| void |
| SPDYF_handler_ignore_frame (struct SPDY_Session *session); |
| |
| #endif |