rtsp_thread.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

  change_state(state, RTP_DATA_UNKNOWN);
  return 0;
}

static int data_unknown (rtsp_client_t *info,
			 rtp_state_t *state)
{
  int blen;
  int ix;

  blen = rtsp_bytes_in_buffer(info);
  if (info->m_offset_on != 0) {
    move_end_of_buffer(info, blen);
  }
  blen = rtsp_receive_socket(info,
			     info->m_resp_buffer + info->m_offset_on,
			     RECV_BUFF_DEFAULT_LEN - info->m_offset_on,
			     0,
			     0);
  if (blen < 0) return -1;
  info->m_buffer_len += blen;

  blen = rtsp_bytes_in_buffer(info);

  for (ix = 0; ix < blen; ix++) {
    if (info->m_resp_buffer[info->m_offset_on] == '$') {
      info->m_offset_on++;
      change_state(state, RTP_HEADER_CHECK);
      return 0;
    } else if (tolower(info->m_resp_buffer[info->m_offset_on]) == 'r') {
      change_state(state, RTSP_HEADER_CHECK);
      return 0;
    } else {
      info->m_offset_on++;
    }
  }
      
  return -1;
}

/*
 * rtsp_thread() - rtsp thread handler - receives and
 * processes all data
 */
int rtsp_thread (void *data)
{
  rtsp_client_t *info = (rtsp_client_t *)data;
  int continue_thread;
  int ret;
  unsigned int ix;
  int state_cont;
  int bytes;
  int got_rtp_pak;
  rtp_state_t state;


  
  continue_thread = 0;
  memset(&state, sizeof(state), 0);
  state.rtp_ptr = NULL;
  state.state = RTP_DATA_UNKNOWN;
  rtsp_thread_init_thread_info(info);
  
  while (continue_thread == 0) {
	//  rtsp_debug(LOG_DEBUG, "thread waiting");
    ret = rtsp_thread_wait_for_event(info);
    if (ret <= 0) {
      if (ret < 0) {
	//rtsp_debug(LOG_ERR, "RTSP loop error %d errno %d", ret, errno);
      } else {
	if (info->server_socket != -1) {
	  for (ix = 0; ix < MAX_RTP_THREAD_SESSIONS; ix++) {
	    if (info->m_callback[ix].rtp_callback_set &&
		info->m_callback[ix].rtp_periodic != NULL) {
	      (info->m_callback[ix].rtp_periodic)(info->m_callback[ix].rtp_userdata);
	    }
	  }
	}
      }
      continue;
    }

    /*
     * See if the communications socket for IPC has any data
     */
	//rtsp_debug(LOG_DEBUG, "Thread checking control");
    ret = rtsp_thread_has_control_message(info);
    
    if (ret) {
      rtsp_msg_type_t msg_type;
      int read;
      /*
       * Yes - read the message type.
       */
      read = rtsp_thread_get_control_message(info, &msg_type);
      if (read == sizeof(msg_type)) {
	// received message
	//rtsp_debug(LOG_DEBUG, "Comm socket msg %d", msg_type);
	switch (msg_type) {
	case RTSP_MSG_QUIT:
	  continue_thread = 1;
	  break;
	case RTSP_MSG_START:
	  ret = rtsp_thread_start_cmd(info);
	  rtsp_thread_ipc_respond(info, ret);
	  break;
	case RTSP_MSG_SEND_AND_GET:
	  ret = rtsp_thread_send_and_get(info);
	  if (ret < 0) {
	    rtsp_thread_ipc_respond(info, ret);
	  } else {
	    // indicate we're supposed to receive...
	    state.receiving_rtsp_response = 1;
	  }
	  break;
	case RTSP_MSG_PERFORM_CALLBACK:
	  ret = rtsp_msg_thread_perform_callback(info);
	  rtsp_thread_ipc_respond(info, ret);
	  break;
	case RTSP_MSG_SET_RTP_CALLBACK:
	  ret = rtsp_msg_thread_set_rtp_callback(info);
	  rtsp_thread_ipc_respond(info, ret);
	  break;
	default:
		rtsp_debug(LOG_ERR, "Unknown message %d received", msg_type);
	}
      }
    }

    /*
     * See if the data socket has any data
     */
	//rtsp_debug(LOG_DEBUG, "Thread checking socket");
    if (info->server_socket != -1) {
      ret = rtsp_thread_has_receive_data(info);
      if (ret) {
	state_cont = 0;
	while (state_cont == 0) {
	  got_rtp_pak = 0;
	  switch (state.state) {
	  case RTP_DATA_UNKNOWN:
	    state_cont = data_unknown(info, &state);
	    break;
	  case RTP_HEADER_CHECK:
	    got_rtp_pak = 1;
	    state_cont = check_rtp_header(info, &state);
	    break;
	  case RTSP_HEADER_CHECK:
	    state_cont = check_rtsp_resp(info, &state);
	    break;
	  case RTP_DATA_START:
	    /*
	     * At the beginning... Either we're getting a $, or getting
	     * a RTP packet.
	     */
	    bytes = rtsp_bytes_in_buffer(info);
	    if (bytes < 4) {
	      if (bytes != 0 && info->m_offset_on != 0) {
		move_end_of_buffer(info, bytes);
	      }
	      ret = rtsp_receive_socket(info,
					info->m_resp_buffer + bytes,
					4 - bytes,
					0,
					0);
	      if (ret < 0) {
		state_cont = 1;
		break;
	      }
	      bytes += ret;
	      info->m_offset_on = 0;
	      info->m_buffer_len = bytes;
	      if (bytes < 4) {
		state_cont  = 1;
		break;
	      }
	    }
	    // we either have a $ - indicating RTP, or a R (for RTSP response)
	    if (info->m_resp_buffer[info->m_offset_on] == '$') {
	      /*
	       * read the 3 byte header - 1 byte for interleaved channel,
	       * 2 byte length.
	       */
	      info->m_offset_on++;
	
	      ret = rtsp_recv(info, state.header, 3);
	      if (ret != 3) continue;
	      state.rtp_len = (state.header[1] << 8) | state.header[2];
	      state_cont = get_rtp_packet(info, &state);
	      got_rtp_pak = 1;
	    } else if (tolower(info->m_resp_buffer[info->m_offset_on]) == 'r') {
	      state_cont = rtsp_get_resp(info, &state);
	    } else {
	      info->m_offset_on++;
	      rtsp_debug(LOG_INFO, "Unknown data %d in rtp stream",
			  info->m_resp_buffer[info->m_offset_on]);
	      change_state(&state, RTP_DATA_UNKNOWN);
	    }
	    break;
	  case RTP_DATA_CONTINUE:
	    state_cont = get_rtp_packet(info, &state);
	    got_rtp_pak = 1;
	    break;
	  }

	  if (got_rtp_pak == 1 && state.try_periodic != 0) {
	    state.try_periodic = 0;
	    ix = state.header[0] / 2;
	    if (info->m_callback[ix].rtp_callback_set &&
		info->m_callback[ix].rtp_periodic != NULL) {
	      (info->m_callback[ix].rtp_periodic)(info->m_callback[ix].rtp_userdata);
	    }
	  }
	}
	
      } // end server_socket has data
    } // end have server socket
  } // end while continue_thread

  SDL_Delay(10);
  /*
   * Okay - we've gotten a quit - we're done
   */
  if (state.rtp_ptr != NULL) {
    xfree(state.rtp_ptr);
  }
  // exiting thread - get rid of the sockets.
  rtsp_thread_close(info);
#ifdef _WINDOWS
  WSACleanup();
#endif
  return 0;
}




int rtsp_thread_perform_callback (rtsp_client_t *info,
				  rtsp_thread_callback_f func,
				  void *ud)
{
  int ret, callback_ret;
  rtsp_wrap_msg_callback_t callback_body;

  callback_body.msg = RTSP_MSG_PERFORM_CALLBACK;
  callback_body.body.func = func;
  callback_body.body.ud = ud;
  
  ret = rtsp_thread_ipc_send_wait(info,
				  (unsigned char *)&callback_body,
				  sizeof(callback_body),
				  &callback_ret);
  if (ret != sizeof(callback_ret)) {
    return -1;
  }
  return (callback_ret);
}

int rtsp_thread_set_rtp_callback (rtsp_client_t *info,
				  rtp_callback_f rtp_callback,
				  rtsp_thread_callback_f rtp_periodic,
				  int rtp_interleave,
				  void *ud)
{
  int ret, callback_ret;
  rtsp_wrap_msg_rtp_callback_t callback_body;

  callback_body.msg = RTSP_MSG_SET_RTP_CALLBACK;
  callback_body.body.callback_func = rtp_callback;
  callback_body.body.periodic_func = rtp_periodic;
  callback_body.body.ud = ud;
  callback_body.body.interleave = rtp_interleave;
  
  ret = rtsp_thread_ipc_send_wait(info,
				  (unsigned char *)&callback_body,
				  sizeof(callback_body),
				  &callback_ret);
  if (ret != sizeof(callback_ret)) {
    return -1;
  }
  return (callback_ret);
}  

/*
 * rtsp_create_client_for_rtp_tcp
 * create threaded rtsp session
 */
rtsp_client_t *rtsp_create_client_for_rtp_tcp (const char *url,
					       int *err)
{
  rtsp_client_t *info;
  int ret;
  rtsp_msg_type_t msg;
  rtsp_msg_resp_t resp;
#if 0
  if (func == NULL) {
    rtsp_debug(LOG_CRIT, "Callback is NULL");
    *err = EINVAL;
    return NULL;
  }
#endif
  info = rtsp_create_client_common(url, err);
  if (info == NULL) return (NULL);
  info->msg_mutex = SDL_CreateMutex();
  if (rtsp_create_thread(info) != 0) {
    free_rtsp_client(info);
    return (NULL);
  }
  msg = RTSP_MSG_START;
  ret = rtsp_thread_ipc_send_wait(info,
				  (unsigned char *)&msg,
				  sizeof(msg),
				  &resp);
  if (ret < 0 || resp < 0) {
    free_rtsp_client(info);
    *err = resp;
    return NULL;
  }
				  
  return (info);
}