rtsp_resp.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

      (header_types[ix].parse_routine)(after, info->decode_response, 0);
      *last_number = ix;
      return;
    }
    ix++;
  }

  if (last_number >= 0 && isspace(*lptr)) {
    //asdf
    ADV_SPACE(lptr);
    (header_types[*last_number].parse_routine)(lptr, info->decode_response, 1);
  } else 
    rtsp_debug(LOG_DEBUG, "Not processing response header: %s", lptr);
}
static int rtsp_read_into_buffer (rtsp_client_t *cptr,
				  uint32_t buffer_offset,
				  int wait)
{
  int ret;

  ret = rtsp_receive_socket(cptr,
			    cptr->m_resp_buffer + buffer_offset,
			    RECV_BUFF_DEFAULT_LEN - buffer_offset,
			    cptr->recv_timeout, 
			    wait);

  if (ret <= 0) return (ret);

  cptr->m_buffer_len = buffer_offset + ret;
  cptr->m_resp_buffer[cptr->m_buffer_len] = '\0';

  return ret;
}

int rtsp_bytes_in_buffer (rtsp_client_t *cptr)
{
  return (cptr->m_buffer_len - cptr->m_offset_on);
}

int rtsp_recv (rtsp_client_t *cptr,
	       char *buffer,
	       uint32_t len)
{
  uint32_t mlen;
  int copied, result;

  copied = 0;
  if (cptr->m_offset_on < cptr->m_buffer_len) {
    mlen =  MIN(len, cptr->m_buffer_len - cptr->m_offset_on);
    memmove(buffer,
	    &cptr->m_resp_buffer[cptr->m_offset_on],
	    mlen);
    cptr->m_offset_on += mlen;
    len -= mlen;
    copied += mlen;
  }
  if (len > 0) {
    result = rtsp_receive_socket(cptr,
				 buffer + copied,
				 len,
				 0,
				 0);
    if (result >= 0) {
      copied += result;
    }
  }
  return copied;
}
    
    
static int rtsp_save_and_read (rtsp_client_t *cptr)
{
  int last_on;
  int ret;
  cptr->m_buffer_len -= cptr->m_offset_on;
  if (cptr->m_buffer_len >= RECV_BUFF_DEFAULT_LEN) {
    return 0;
  } else if (cptr->m_buffer_len != 0) {
    memmove(cptr->m_resp_buffer,
	    &cptr->m_resp_buffer[cptr->m_offset_on],
	    cptr->m_buffer_len);
    last_on = cptr->m_buffer_len;
  } else {
    last_on = 0;
  }
  
  cptr->m_offset_on = 0;  
  ret = rtsp_read_into_buffer(cptr, cptr->m_buffer_len, 0);
  if (ret > 0) {
    last_on += ret;
  }
  return (last_on);
}

static const char *rtsp_get_next_line (rtsp_client_t *cptr,
				       const char *seperator)
{
  int ret;
  int last_on;
  char *sep;

  /*
   * If we don't have any data, try to read a buffer full
   */
  if (cptr->m_buffer_len <= 0) {
    cptr->m_offset_on = 0;
    ret = rtsp_read_into_buffer(cptr, 0, 1);
    if (ret <= 0) {
      return (NULL);
    }
  }

  /*
   * Look for CR/LF in the buffer.  If we find it, NULL terminate at
   * the CR, then set the buffer values to look past the crlf
   */
  sep = strstr(&cptr->m_resp_buffer[cptr->m_offset_on],
	       seperator);
  if (sep != NULL) {
    const char *retval = &cptr->m_resp_buffer[cptr->m_offset_on];
    cptr->m_offset_on = sep - cptr->m_resp_buffer;
    cptr->m_offset_on += strlen(seperator);
    *sep = '\0';
    return (retval);
  }

  if (cptr->m_offset_on == 0) {
    return (NULL);
  }

  /*
   * We don't have a line.  So, move the data down in the buffer, then
   * read into the rest of the buffer
   */
  last_on = rtsp_save_and_read(cptr);
  if (last_on < 0) return (NULL);
  /*
   * Continue searching through the buffer.  If we get this far, we've
   * received like 2K or 4K without a CRLF - most likely a bad response
   */
  sep = strstr(&cptr->m_resp_buffer[last_on],
	       seperator);
  if (sep != NULL) {
    const char *retval = &cptr->m_resp_buffer[cptr->m_offset_on];
    cptr->m_offset_on = sep - cptr->m_resp_buffer;
    cptr->m_offset_on += strlen(seperator);
    *sep = '\0';
    return (retval);
  }
  return (NULL);
}
/*
 * rtsp_parse_response - parse out response headers lines.  Figure out
 * where seperators are, then use them to determine where the body is
 */
static int rtsp_parse_response (rtsp_client_t *info)
{
  const char *seperator;
  const char *lptr, *p;
  rtsp_decode_t *decode;
  int ret, done;
  int last_header = -1;
  uint32_t len;

  decode = info->decode_response;
  
  // Figure out what seperator is being used throughout the response
  ret = rtsp_save_and_read(info);
  if (ret < 0) {
    return (RTSP_RESPONSE_RECV_ERROR);
  }

  seperator = find_seperator(info->m_resp_buffer);
  if (seperator == NULL) {
    rtsp_debug(LOG_INFO, "Could not find seperator in header");
    return RTSP_RESPONSE_MALFORM_HEADER;
  }
  
  //rtsp_debug(LOG_DEBUG, "Response buffer:\n%s", info->m_resp_buffer);

  do {
    lptr = rtsp_get_next_line(info, seperator);
    if (lptr == NULL) {
      rtsp_debug(LOG_INFO, "Couldn't get next line");
      return (RTSP_RESPONSE_MALFORM_HEADER);
    }
  } while (*lptr == '\0');

  rtsp_debug(LOG_DEBUG, lptr);
  if (strncasecmp(lptr, "RTSP/1.0", strlen("RTSP/1.0")) != 0) {
    rtsp_debug(LOG_INFO, "RTSP/1.0 not found");
    return RTSP_RESPONSE_MALFORM_HEADER;
  }
  p = lptr + strlen("RTSP/1.0");
  ADV_SPACE(p);
  memcpy(decode->retcode, p, 3);
  decode->retcode[3] = '\0';
	
  switch (*p) {
  case '1':
  case '2':
  case '3':
  case '4':
  case '5':
    break;
  default:
    rtsp_debug(LOG_INFO, "Bad error code %s", p);
    return RTSP_RESPONSE_MALFORM_HEADER;
  }
  p += 3;
  ADV_SPACE(p);
  if (p != '\0') {
    decode->retresp = strdup(p);
  }
  rtsp_debug(LOG_DEBUG, "Decoded status - code %s %s",
	     decode->retcode, decode->retresp);
  done = 0;
  do {
    lptr = rtsp_get_next_line(info, seperator);

    if (lptr == NULL) {
      return (RTSP_RESPONSE_MALFORM_HEADER);
    }
    if (*lptr == '\0') {
      done = 1;
    } else {
      rtsp_debug(LOG_DEBUG, lptr);
      rtsp_decode_header(lptr, info, &last_header);
    }
  } while (done == 0);

  if (decode->content_length != 0) {
    rtsp_debug(LOG_DEBUG, "reading content length %d", decode->content_length);
    decode->body = malloc(decode->content_length + 1);
    decode->body[decode->content_length] = '\0';
    len = info->m_buffer_len - info->m_offset_on;
    rtsp_debug(LOG_DEBUG, "Copied %d bytes from buffer", len);
    if (len < decode->content_length) {
      // not enough in memory - need to read
      memcpy(decode->body,
	     &info->m_resp_buffer[info->m_offset_on],
	     len);
      while (len < decode->content_length) {
	int left;
	ret = rtsp_read_into_buffer(info, 0, 1);
	
	if (ret <= 0) {
	  rtsp_debug(LOG_DEBUG, "Returned from rtsp_read_into_buffer - error %d", 
		     ret);
	  return (-1);
	}
	left = decode->content_length - len;
	if (left < info->m_buffer_len) {
	  // we have more data in the buffer then we need
	  memcpy(decode->body + len,
		 info->m_resp_buffer,
		 left);
	  len += left;
	  info->m_offset_on = left;
	} else {
	  // exact or less - we're cool
	  memcpy(decode->body + len,
		 info->m_resp_buffer,
		 info->m_buffer_len);
	  len += info->m_buffer_len;
	  info->m_offset_on = info->m_buffer_len; // get ready for next...
	}
      }
    } else {
      // Plenty in memory - copy it, continue to end...
      memcpy(decode->body,
	     &info->m_resp_buffer[info->m_offset_on],
	     decode->content_length);
      info->m_offset_on += decode->content_length;
    }
  } else if (decode->close_connection) {
    // No termination - just deal with what we've got...
    len = info->m_buffer_len - info->m_offset_on;
    decode->body = (char *)malloc(len + 1);
    memcpy(decode->body,
	   &info->m_resp_buffer[info->m_offset_on],
	   len);
    decode->body[len] = '\0';
  }
  if (decode->body != NULL)
     rtsp_debug(LOG_DEBUG, "%s", decode->body);
  return (0);
}

/*
 * rtsp_get_response - wait for a complete response.  Interesting that
 * it could be in multiple packets, so deal with that.
 */
int rtsp_get_response (rtsp_client_t *info)
{
  int ret;
  rtsp_decode_t *decode;
  int response_okay;

  while (1) {
    // In case we didn't get a response that we wanted.
    if (info->decode_response != NULL) {
      clear_decode_response(info->decode_response);
      decode = info->decode_response;
    } else {
      decode = info->decode_response = malloc(sizeof(rtsp_decode_t));
      if (decode == NULL) {
	rtsp_debug(LOG_ALERT, "Couldn't create decode response");
	return (RTSP_RESPONSE_RECV_ERROR);
      }
    }
    
    memset(decode, 0, sizeof(rtsp_decode_t));

    do {
      // Parse response.
      ret = rtsp_parse_response(info);
      rtsp_debug(LOG_DEBUG, "parsed response - len %d offset %d",
		 info->m_buffer_len, info->m_offset_on);
      if (ret != 0) {
	if (info->thread == NULL)
	  rtsp_close_socket(info);
	rtsp_debug(LOG_ERR, "return code %d from rtsp_parse_response", ret);
	return (RTSP_RESPONSE_RECV_ERROR);
      }

      if (decode->close_connection) {
	rtsp_debug(LOG_DEBUG, "Response requested connection close");
	rtsp_close_socket(info);
      }
  
      response_okay = TRUE;
      // Okay - we have a good response. - check the cseq, and return
      // the correct error code.
      if (info->next_cseq == decode->cseq) {
	info->next_cseq++;
	if ((decode->retcode[0] == '4') ||
	    (decode->retcode[0] == '5')) {
	  return (RTSP_RESPONSE_BAD);
	}
	if (decode->cookie != NULL) {
	  // move cookie to rtsp_client
	  info->cookie = strdup(decode->cookie);
	}
	if (decode->retcode[0] == '2') {
	  return (RTSP_RESPONSE_GOOD);
	}
	if (decode->retcode[0] == '3') {
	  if (decode->location == NULL) {
	    return (RTSP_RESPONSE_BAD);
	  }
	  if (rtsp_setup_redirect(info) != 0) {
	    return (RTSP_RESPONSE_BAD);
	  }
	  return (RTSP_RESPONSE_REDIRECT);
	}
      }
#if 0
      if (info->m_buffer_len != 0) {
	// We have more in the buffer - see if it's what
	// we need
	// clear out last response
	clear_decode_response(decode);
	memset(decode, 0, sizeof(rtsp_decode_t));
      }
#endif
    } while (info->m_buffer_len != 0);
  } 
  return (RTSP_RESPONSE_RECV_ERROR);
}

/* end file rtsp_resp.c */