netcam.c

video motion detection of linux base

			return -1;
		}
		if (firstflag) {
			if ((ret = http_result_code(header)) != 200) {
				if (debug_level > 5)
					motion_log(-1, 0, "HTTP Result code %d", ret);
				free(header);
				return ret;
			}
			firstflag = 0;
			free(header);
			continue;
		}
		if (*header == 0)                  /* blank line received */
			break;

		if (SETUP)
			motion_log(LOG_DEBUG, 0, "Received first header");

		/* Check if this line is the content type */
		if ((ret = netcam_check_content_type(header)) >= 0) {
			retval = ret;
			/*
			 * We are expecting to find one of three types:
			 * 'multipart/x-mixed-replace', 'multipart/mixed'
			 * or 'image/jpeg'.  The first two will be received
			 * from a streaming camera, and the third from a
			 * camera which provides a single frame only.
			 */
			switch (ret) {
				case 1:         /* not streaming */
					if (SETUP)
						motion_log(LOG_DEBUG, 0, "Non-streaming camera");

					netcam->caps.streaming = 0;
					break;

				case 2:         /* streaming */
					if (SETUP)
						motion_log(LOG_DEBUG, 0, "Streaming camera");

					netcam->caps.streaming = 1;

					if ((boundary = strstr(header, "boundary="))) {
						/*
						 * on error recovery this
						 * may already be set
						 * */
						if (netcam->boundary)
							free(netcam->boundary);

						netcam->boundary = strdup(boundary + 9);
						/*
						 * HTTP protocol apparently permits the boundary string
						 * to be quoted (the Lumenera does this, which caused
						 * trouble) so we need to get rid of any surrounding
						 * quotes
						 */
						check_quote(netcam->boundary);
						netcam->boundary_length = strlen(netcam->boundary);

						if (SETUP) {
							motion_log(LOG_DEBUG, 0, "Boundary string [%s]",
							           netcam->boundary);
						}
					}
					break;

				default:{       /* error */
						motion_log(LOG_ERR, 0, "Unrecognized content type");
						free(header);
						return -1;
					}
			}
		} else if ((ret = (int) netcam_check_content_length(header)) >= 0) {
			if (SETUP)
				motion_log(LOG_DEBUG, 0, "Content-length present");

			netcam->caps.content_length = 1;     /* set flag */
			netcam->receiving->content_length = ret;
		}
		free(header);
	}
	free(header);

	return retval;
}

/**
 * netcam_disconnect
 *
 *      Disconnect from the network camera.
 *
 * Parameters:
 *
 *      netcam  pointer to netcam context
 *
 * Returns:     Nothing
 *
 */
static void netcam_disconnect(netcam_context_ptr netcam)
{

	if (netcam->sock > 0) {
		if (close(netcam->sock) < 0)
			motion_log(LOG_ERR, 1, "netcam_disconnect");

		netcam->sock = -1;
	}
}

/**
 * netcam_connect
 *
 *      Attempt to open the network camera as a stream device.
 *
 * Parameters:
 *
 *      netcam    pointer to netcam_context structure
 *      err_flag  flag to suppress error printout (1 => suppress)
 *                Note that errors which indicate something other than
 *                a network connection problem are not suppressed.
 *
 * Returns:     0 for success, -1 for error
 *
 */
static int netcam_connect(netcam_context_ptr netcam, int err_flag)
{
	struct sockaddr_in server;      /* for connect */
	struct addrinfo *res;           /* for getaddrinfo */
	int ret;
	int saveflags;
	int back_err;
	socklen_t len;
	fd_set fd_w;
	struct timeval selecttime;

	/* Assure any previous connection has been closed */
	netcam_disconnect(netcam);

	/* create a new socket */
	if ((netcam->sock = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
		motion_log(LOG_ERR, 1, "Attempting to create socket");
		return -1;
	}

	/* lookup the hostname given in the netcam URL */
	if ((ret = getaddrinfo(netcam->connect_host, NULL, NULL, &res)) != 0) {
		if (!err_flag)
			motion_log(LOG_ERR, 0, "getaddrinfo() failed (%s): %s",
			           netcam->connect_host, gai_strerror(ret));
		netcam_disconnect(netcam);
		return -1;
	}

	/*
	 * Fill the hostname details into the 'server' structure and
	 * attempt to connect to the remote server
	 */
	memset(&server, 0, sizeof(server));
	memcpy(&server, res->ai_addr, sizeof(server));
	freeaddrinfo(res);

	server.sin_family = AF_INET;
	server.sin_port = htons(netcam->connect_port);

	/*
	 * We set the socket non-blocking and then use a 'select'
	 * system call to control the timeout.
	 */

	if ((saveflags = fcntl(netcam->sock, F_GETFL, 0)) < 0) {
		motion_log(LOG_ERR, 1, "fcntl(1) on socket");
		netcam_disconnect(netcam);
		return -1;
	}

	/* Set the socket non-blocking */
	if (fcntl(netcam->sock, F_SETFL, saveflags | O_NONBLOCK) < 0) {
		motion_log(LOG_ERR, 1, "fcntl(2) on socket");
		netcam_disconnect(netcam);
		return -1;
	}

	/* Now the connect call will return immediately */
	ret = connect(netcam->sock, (struct sockaddr *) &server,
	              sizeof(server));
	back_err = errno;           /* save the errno from connect */

	/* If the connect failed with anything except EINPROGRESS, error */
	if ((ret < 0) && (back_err != EINPROGRESS)) {
		if (!err_flag)
			motion_log(LOG_ERR, 1, "connect() failed (%d)", back_err);
		netcam_disconnect(netcam);
		return -1;
	}

	/* Now we do a 'select' with timeout to wait for the connect */
	FD_ZERO(&fd_w);
	FD_SET(netcam->sock, &fd_w);
	selecttime.tv_sec = CONNECT_TIMEOUT;
	selecttime.tv_usec = 0;
	ret = select(FD_SETSIZE, NULL, &fd_w, NULL, &selecttime);

	if (ret == 0) {            /* 0 means timeout */
		if (!err_flag)
			motion_log(LOG_ERR, 0, "timeout on connect()");
		netcam_disconnect(netcam);
		return -1;
	}

	/*
	 * A +ve value returned from the select (actually, it must be a
	 * '1' showing 1 fd's changed) shows the select has completed.
	 * Now we must check the return code from the select.
	 */
	len = sizeof(ret);

	if (getsockopt(netcam->sock, SOL_SOCKET, SO_ERROR, &ret, &len) < 0) {
		motion_log(LOG_ERR, 0, "getsockopt after connect");
		netcam_disconnect(netcam);
		return -1;
	}

	/* If the return code is anything except 0, error on connect */
	if (ret) {
		if (!err_flag)
			motion_log(LOG_ERR, 1, "connect returned error");
		netcam_disconnect(netcam);
		return -1;
	}

	/* The socket info is stored in the rbuf structure of our context */
	rbuf_initialize(netcam);

	return 0;            /* success */
}


/**
 * netcam_check_buffsize
 *
 * This routine checks whether there is enough room in a buffer to copy
 * some additional data.  If there is not enough room, it will re-allocate
 * the buffer and adjust it's size.
 *
 * Parameters:
 *      buff            Pointer to a netcam_image_buffer structure
 *      numbytes        The number of bytes to be copied
 *
 * Returns:             Nothing
 */
static void netcam_check_buffsize(netcam_buff_ptr buff, size_t numbytes)
{
	if ((buff->size - buff->used) >= numbytes)
		return;

	if (debug_level > CAMERA_INFO)
		motion_log(-1, 0, "expanding buffer from %d to %d bytes",
		           (int) buff->size, (int) buff->size + NETCAM_BUFFSIZE);

	buff->ptr = myrealloc(buff->ptr, buff->size + NETCAM_BUFFSIZE,
	                      "netcam_check_buf_size");
	buff->size += NETCAM_BUFFSIZE;
}

/**
 * netcam_read_html_jpeg
 *
 * This routine reads a jpeg image from the netcam.  When it is called,
 * the stream is already positioned just after the image header.
 *
 * This routine is called under the four variations of two different
 * conditions:
 * 	1) Streaming or non-streaming camera
 * 	2) Header does or does not include Content-Length
 * Additionally, if it is a streaming camera, there must always be a
 * boundary-string.
 *
 * The routine will (attempt to) read the JPEG image.  If a Content-Length
 * is present, it will be used (this will result in more efficient code, and
 * also code which should be better at detecting and recovering from possible
 * error conditions).
 *
 * If a boundary-string is present (and, if the camera is streaming, this
 * *must* be the case), the routine will assure that it is recognized and
 * acted upon.
 *
 * Our algorithm for this will be as follows:
 * 	1) If a Content-Length is present, set the variable "remaining"
 * 	   to be equal to that value, else set it to a "very large"
 * 	   number.
 * 	2) While there is more data available from the camera:
 * 	   a) If there is a "boundary string" specified (from the initial
 * 	      header):
 * 	      i)   If the amount of data in the input buffer is less than
 * 	           the length of the boundary string, get more data into
 * 	           the input buffer (error if failure).
 * 	      ii)  If the boundary string is found, check how many
 * 	           characters remain in the input buffer before the start
 * 	           of the boundary string.  If that is less than the
 * 	           variable "remaining", reset "remaining" to be equal
 * 	           to that number.
 * 	   b) Try to copy up to "remaining" characters from the input
 * 	      buffer into our destination buffer.
 * 	   c) If there are no more characters available from the camera,
 * 	      exit this loop, else subtract the number of characters
 * 	      actually copied from the variable "remaining".
 * 	3) If Content-Length was present, and "remaining" is not equal
 * 	   to zero, generate a warning message for logging.
 *
 *
 * Parameters:
 *      netcam          Pointer to netcam context
 *
 *
 * Returns:             0 for success, -1 for error
 *
 */
static int netcam_read_html_jpeg(netcam_context_ptr netcam)
{
	netcam_buff_ptr buffer;
	size_t remaining;       /* # characters to read */
	size_t maxflush;        /* # chars before boundary */
	size_t rem, rlen, ix;   /* working vars */
	int retval;
	char *ptr, *bptr, *rptr;
	netcam_buff *xchg;
	struct timeval curtime;
	/*
	 * Initialisation - set our local pointers to the context
	 * information
	 */
	buffer = netcam->receiving;
	/* Assure the target buffer is empty */
	buffer->used = 0;
	/* Prepare for read loop */
	if (buffer->content_length != 0)
		remaining = buffer->content_length;
	else
		remaining = 999999;

	/* Now read in the data */
	while (remaining) {
		/* Assure data in input buffer */
		if (netcam->response->buffer_left <= 0) {
			retval = rbuf_read_bufferful(netcam);

			if (retval <= 0)
				break;

			netcam->response->buffer_left = retval;
			netcam->response->buffer_pos = netcam->response->buffer;
		}

		/* If a boundary string is present, take it into account */
		bptr = netcam->boundary;

		if (bptr) {
			rptr = netcam->response->buffer_pos;
			rlen = netcam->response->buffer_left;

			/* Loop through buffer looking for start of boundary */
			while (1) {
				/*
				 * Logic gets a little complicated here.  The
				 * problem is that we are reading in input
				 * data in packets, and there is a (small)
				 * chance that the boundary string could be
				 * split across successive packets.
				 * First a quick check if the string *might*
				 * be in the current buffer.
				 */
				if (rlen > remaining)
					rlen = remaining;

				if (remaining < netcam->boundary_length)
					break;

				if ((ptr = memchr(rptr, *bptr, rlen)) == NULL)
					/* boundary not here (normal path) */
					break;
				/*
				 * At least the first char was found in the
				 * buffer - check for the rest
				 */
				rem = rlen - (ptr - rptr);
				for (ix = 1; (ix < rem) && (ix < netcam->boundary_length); ix++) {
					if (ptr[ix] != bptr[ix])
						break;
				}

				if ((ix != netcam->boundary_length) && (ix != rem)) {
					/*
					 * Not pointing at a boundary string -
					 * step along input
					 */
					ix = ptr - rptr + 1;
					rptr += ix;
					rlen -= ix;

					if (rlen <= 0)
						/* boundary not in buffer - go copy out
						 */
						break;
					/*
					 * not yet decided - continue
					 * through input
					 */
					continue;
				}
				/*
				 * If we finish the 'for' with
				 * ix == boundary_length, that means we found
				 * the string, and should copy any data which
				 * precedes it into the target buffer, then
				 * exit the main loop.
				 */
				if (ix == netcam->boundary_length) {
					if ((ptr - netcam->response->buffer) < (int) remaining)
						remaining = ptr - netcam->response->buffer;

					/* go copy everything up to boundary */
					break;
				}

				/*
				 * If not, and ix == rem, that means we reached
				 * the end of the input buffer in the middle of
				 * our check, which is the (somewhat messy)
				 * problem mentioned above.
				 *
				 * Assure there is data before potential
				 * boundary string
				 */
				if (ptr != netcam->response->buffer) {
					/*
					 * We have a boundary string crossing
					 * packets :-(. We will copy all the
					 * data up to the beginning of the
					 * potential boundary, then re-position
					 * the (partial) string to the
					 * beginning and get some more input
					 * data.  First we flush the input
					 * buffer up to the beginning of the
					 * (potential) boundary string
					 */
					ix = ptr - netcam->response->buffer_pos;
					netcam_check_buffsize(buffer, ix);
					retval = rbuf_flush(netcam, buffer->ptr + buffer->used, ix);
					buffer->used += retval;
					remaining -= retval;

					/*
					 * Now move the boundary fragment to
					 * the head of the input buffer.
					 * This is really a "hack" - ideally,
					 * we should have a function within the
					 * module netcam_wget.c to do this job!
					 */

					if (debug_level > CAMERA_INFO) {
						motion_log(-1, 0,
						           "Potential split boundary - "
						           "%d chars flushed, %d "
						           "re-positioned", ix,
						           (int) netcam->response->buffer_left);
					}

					memmove(netcam->response->buffer, ptr,
					         netcam->response->buffer_left);
				}       /* end of boundary split over buffer */

				retval = netcam_recv(netcam, netcam->response->buffer +
				                     netcam->response->buffer_left,
				                     sizeof(netcam->response->buffer) -
				                     netcam->response->buffer_left);

				if (retval <= 0) { /* this is a fatal error */
					motion_log(LOG_ERR, 1, "recv() fail after boundary string");
					return -1;
				}

				/* Reset the input buffer pointers */
				netcam->response->buffer_left = retval + netcam->response->buffer_left;
				netcam->response->buffer_pos = netcam->response->buffer;