gstreamer/gst/tcp/gsttcp.c
2011-10-10 11:39:52 +02:00

475 lines
12 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) <2004> Thomas Vander Stichele <thomas at apestaart dot org>
*
* gsttcp.c: TCP functions
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <sys/ioctl.h>
#ifdef HAVE_FIONREAD_IN_SYS_FILIO
#include <sys/filio.h>
#endif
#include "gsttcp.h"
#include <gst/gst-i18n-plugin.h>
GST_DEBUG_CATEGORY_EXTERN (tcp_debug);
#define GST_CAT_DEFAULT tcp_debug
#ifndef MSG_NOSIGNAL
#define MSG_NOSIGNAL 0
#endif
/* resolve host to IP address, throwing errors if it fails */
/* host can already be an IP address */
/* returns a newly allocated gchar * with the dotted ip address,
or NULL, in which case it already fired an error. */
gchar *
gst_tcp_host_to_ip (GstElement * element, const gchar * host)
{
struct hostent *hostinfo;
char **addrs;
gchar *ip;
struct in_addr addr;
GST_DEBUG_OBJECT (element, "resolving host %s", host);
/* first check if it already is an IP address */
if (inet_aton (host, &addr)) {
ip = g_strdup (host);
goto beach;
}
/* FIXME: could do a localhost check here */
/* perform a name lookup */
if (!(hostinfo = gethostbyname (host)))
goto resolve_error;
if (hostinfo->h_addrtype != AF_INET)
goto not_ip;
addrs = hostinfo->h_addr_list;
/* There could be more than one IP address, but we just return the first */
ip = g_strdup (inet_ntoa (*(struct in_addr *) *addrs));
beach:
GST_DEBUG_OBJECT (element, "resolved to IP %s", ip);
return ip;
resolve_error:
{
GST_ELEMENT_ERROR (element, RESOURCE, NOT_FOUND, (NULL),
("Could not find IP address for host \"%s\".", host));
return NULL;
}
not_ip:
{
GST_ELEMENT_ERROR (element, RESOURCE, NOT_FOUND, (NULL),
("host \"%s\" is not an IP host", host));
return NULL;
}
}
/* write buffer to given socket incrementally.
* Returns number of bytes written.
*/
gint
gst_tcp_socket_write (int socket, const void *buf, size_t count)
{
size_t bytes_written = 0;
while (bytes_written < count) {
ssize_t wrote = send (socket, (const char *) buf + bytes_written,
count - bytes_written, MSG_NOSIGNAL);
if (wrote <= 0) {
GST_WARNING ("error while writing");
return bytes_written;
}
bytes_written += wrote;
}
GST_LOG ("wrote %" G_GSIZE_FORMAT " bytes succesfully", bytes_written);
return bytes_written;
}
/* atomically read count bytes into buf, cancellable. return val of GST_FLOW_OK
* indicates success, anything else is failure.
*/
static GstFlowReturn
gst_tcp_socket_read (GstElement * this, int socket, void *buf, size_t count,
GstPoll * fdset)
{
ssize_t n;
size_t bytes_read;
int num_to_read;
int ret;
bytes_read = 0;
while (bytes_read < count) {
/* do a blocking select on the socket */
/* no action (0) is an error too in our case */
if ((ret = gst_poll_wait (fdset, GST_CLOCK_TIME_NONE)) <= 0) {
if (ret == -1 && errno == EBUSY)
goto cancelled;
else
goto select_error;
}
/* ask how much is available for reading on the socket */
if (ioctl (socket, FIONREAD, &num_to_read) < 0)
goto ioctl_error;
if (num_to_read == 0)
goto got_eos;
/* sizeof(ssize_t) >= sizeof(int), so I know num_to_read <= SSIZE_MAX */
num_to_read = MIN (num_to_read, count - bytes_read);
n = read (socket, ((guint8 *) buf) + bytes_read, num_to_read);
if (n < 0)
goto read_error;
if (n < num_to_read)
goto short_read;
bytes_read += num_to_read;
}
return GST_FLOW_OK;
/* ERRORS */
select_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("select failed: %s", g_strerror (errno)));
return GST_FLOW_ERROR;
}
cancelled:
{
GST_DEBUG_OBJECT (this, "Select was cancelled");
return GST_FLOW_WRONG_STATE;
}
ioctl_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("ioctl failed: %s", g_strerror (errno)));
return GST_FLOW_ERROR;
}
got_eos:
{
GST_DEBUG_OBJECT (this, "Got EOS on socket stream");
return GST_FLOW_EOS;
}
read_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("read failed: %s", g_strerror (errno)));
return GST_FLOW_ERROR;
}
short_read:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("short read: wanted %d bytes, got %" G_GSSIZE_FORMAT, num_to_read, n));
return GST_FLOW_ERROR;
}
}
/* close the socket and reset the fd. Used to clean up after errors. */
void
gst_tcp_socket_close (GstPollFD * socket)
{
if (socket->fd >= 0) {
close (socket->fd);
socket->fd = -1;
}
}
/* read a buffer from the given socket
* returns:
* - a GstBuffer in which data should be read
* - NULL, indicating a connection close or an error, to be handled with
* EOS
*/
GstFlowReturn
gst_tcp_read_buffer (GstElement * this, int socket, GstPoll * fdset,
GstBuffer ** buf)
{
int ret;
gssize bytes_read;
int readsize;
guint8 *data;
*buf = NULL;
/* do a blocking select on the socket */
/* no action (0) is an error too in our case */
if ((ret = gst_poll_wait (fdset, GST_CLOCK_TIME_NONE)) <= 0) {
if (ret == -1 && errno == EBUSY)
goto cancelled;
else
goto select_error;
}
/* ask how much is available for reading on the socket */
if (ioctl (socket, FIONREAD, &readsize) < 0)
goto ioctl_error;
if (readsize == 0)
goto got_eos;
/* sizeof(ssize_t) >= sizeof(int), so I know readsize <= SSIZE_MAX */
*buf = gst_buffer_new_and_alloc (readsize);
data = gst_buffer_map (*buf, NULL, NULL, GST_MAP_WRITE);
bytes_read = read (socket, data, readsize);
gst_buffer_unmap (*buf, data, bytes_read);
if (bytes_read < 0)
goto read_error;
if (bytes_read < readsize)
/* but mom, you promised to give me readsize bytes! */
goto short_read;
GST_LOG_OBJECT (this,
"returning buffer of size %" G_GSSIZE_FORMAT, bytes_read);
return GST_FLOW_OK;
/* ERRORS */
select_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("select failed: %s", g_strerror (errno)));
return GST_FLOW_ERROR;
}
cancelled:
{
GST_DEBUG_OBJECT (this, "Select was cancelled");
return GST_FLOW_WRONG_STATE;
}
ioctl_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("ioctl failed: %s", g_strerror (errno)));
return GST_FLOW_ERROR;
}
got_eos:
{
GST_DEBUG_OBJECT (this, "Got EOS on socket stream");
return GST_FLOW_EOS;
}
read_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("read failed: %s", g_strerror (errno)));
gst_buffer_unref (*buf);
*buf = NULL;
return GST_FLOW_ERROR;
}
short_read:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("short read: wanted %d bytes, got %" G_GSSIZE_FORMAT, readsize,
bytes_read));
gst_buffer_unref (*buf);
*buf = NULL;
return GST_FLOW_ERROR;
}
}
/* read a buffer from the given socket
* returns:
* - a GstBuffer in which data should be read
* - NULL, indicating a connection close or an error, to be handled with
* EOS
*/
GstFlowReturn
gst_tcp_gdp_read_buffer (GstElement * this, int socket, GstPoll * fdset,
GstBuffer ** buf)
{
GstFlowReturn ret;
guint8 *header = NULL;
guint8 *data;
gsize size;
GST_LOG_OBJECT (this, "Reading %d bytes for buffer packet header",
GST_DP_HEADER_LENGTH);
*buf = NULL;
header = g_malloc (GST_DP_HEADER_LENGTH);
ret = gst_tcp_socket_read (this, socket, header, GST_DP_HEADER_LENGTH, fdset);
if (ret != GST_FLOW_OK)
goto header_read_error;
if (!gst_dp_validate_header (GST_DP_HEADER_LENGTH, header))
goto validate_error;
if (gst_dp_header_payload_type (header) != GST_DP_PAYLOAD_BUFFER)
goto is_not_buffer;
GST_LOG_OBJECT (this, "validated buffer packet header");
*buf = gst_dp_buffer_from_header (GST_DP_HEADER_LENGTH, header);
g_free (header);
data = gst_buffer_map (*buf, &size, NULL, GST_MAP_WRITE);
ret = gst_tcp_socket_read (this, socket, data, size, fdset);
gst_buffer_unmap (*buf, data, size);
if (ret != GST_FLOW_OK)
goto data_read_error;
return GST_FLOW_OK;
/* ERRORS */
header_read_error:
{
g_free (header);
return ret;
}
validate_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("GDP buffer packet header does not validate"));
g_free (header);
return GST_FLOW_ERROR;
}
is_not_buffer:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("GDP packet contains something that is not a buffer (type %d)",
gst_dp_header_payload_type (header)));
g_free (header);
return GST_FLOW_ERROR;
}
data_read_error:
{
gst_buffer_unref (*buf);
*buf = NULL;
return ret;
}
}
GstFlowReturn
gst_tcp_gdp_read_caps (GstElement * this, int socket, GstPoll * fdset,
GstCaps ** caps)
{
GstFlowReturn ret;
guint8 *header = NULL;
guint8 *payload = NULL;
size_t payload_length;
GST_LOG_OBJECT (this, "Reading %d bytes for caps packet header",
GST_DP_HEADER_LENGTH);
*caps = NULL;
header = g_malloc (GST_DP_HEADER_LENGTH);
ret = gst_tcp_socket_read (this, socket, header, GST_DP_HEADER_LENGTH, fdset);
if (ret != GST_FLOW_OK)
goto header_read_error;
if (!gst_dp_validate_header (GST_DP_HEADER_LENGTH, header))
goto header_validate_error;
if (gst_dp_header_payload_type (header) != GST_DP_PAYLOAD_CAPS)
goto is_not_caps;
GST_LOG_OBJECT (this, "validated caps packet header");
payload_length = gst_dp_header_payload_length (header);
payload = g_malloc (payload_length);
GST_LOG_OBJECT (this,
"Reading %" G_GSIZE_FORMAT " bytes for caps packet payload",
payload_length);
ret = gst_tcp_socket_read (this, socket, payload, payload_length, fdset);
if (ret != GST_FLOW_OK)
goto payload_read_error;
if (!gst_dp_validate_payload (GST_DP_HEADER_LENGTH, header, payload))
goto payload_validate_error;
*caps = gst_dp_caps_from_packet (GST_DP_HEADER_LENGTH, header, payload);
GST_DEBUG_OBJECT (this, "Got caps over GDP: %" GST_PTR_FORMAT, *caps);
g_free (header);
g_free (payload);
return GST_FLOW_OK;
/* ERRORS */
header_read_error:
{
g_free (header);
return ret;
}
header_validate_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("GDP caps packet header does not validate"));
g_free (header);
return GST_FLOW_ERROR;
}
is_not_caps:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("GDP packet contains something that is not a caps (type %d)",
gst_dp_header_payload_type (header)));
g_free (header);
return GST_FLOW_ERROR;
}
payload_read_error:
{
g_free (header);
g_free (payload);
return ret;
}
payload_validate_error:
{
GST_ELEMENT_ERROR (this, RESOURCE, READ, (NULL),
("GDP caps packet payload does not validate"));
g_free (header);
g_free (payload);
return GST_FLOW_ERROR;
}
}