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/* GStreamer
* Copyright (C) 2005 Andy Wingo <wingo@pobox.com>
*
* 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.
*/
/**
* SECTION:gstnettimepacket
* @short_description: Helper structure to construct clock packets used
* by network clocks.
* @see_also: #GstClock, #GstNetClientClock, #GstNetTimeProvider
*
* Various functions for receiving, sending an serializing #GstNetTimePacket
* structures.
*
* Last reviewed on 2005-11-23 (0.9.5)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <glib.h>
#ifdef __CYGWIN__
# include <unistd.h>
# include <fcntl.h>
#endif
#include "gstnettimepacket.h"
/**
* gst_net_time_packet_new:
* @buffer: a buffer from which to construct the packet, or NULL
*
* Creates a new #GstNetTimePacket from a buffer received over the network. The
* caller is responsible for ensuring that @buffer is at least
* #GST_NET_TIME_PACKET_SIZE bytes long.
*
* If @buffer is #NULL, the local and remote times will be set to
* #GST_CLOCK_TIME_NONE.
*
* MT safe. Caller owns return value (g_free to free).
*
* Returns: The new #GstNetTimePacket.
*/
GstNetTimePacket *
gst_net_time_packet_new (const guint8 * buffer)
{
GstNetTimePacket *ret;
g_assert (sizeof (GstClockTime) == 8);
ret = g_new0 (GstNetTimePacket, 1);
if (buffer) {
ret->local_time = GST_READ_UINT64_BE (buffer);
ret->remote_time = GST_READ_UINT64_BE (buffer + sizeof (GstClockTime));
} else {
ret->local_time = GST_CLOCK_TIME_NONE;
ret->remote_time = GST_CLOCK_TIME_NONE;
}
return ret;
}
/**
* gst_net_time_packet_serialize:
* @packet: the #GstNetTimePacket
*
* Serialized a #GstNetTimePacket into a newly-allocated sequence of
* #GST_NET_TIME_PACKET_SIZE bytes, in network byte order. The value returned is
* suitable for passing to write(2) or sendto(2) for communication over the
* network.
*
* MT safe. Caller owns return value (g_free to free).
*
* Returns: A newly allocated sequence of #GST_NET_TIME_PACKET_SIZE bytes.
*/
guint8 *
gst_net_time_packet_serialize (const GstNetTimePacket * packet)
{
guint8 *ret;
g_assert (sizeof (GstClockTime) == 8);
ret = g_new0 (guint8, GST_NET_TIME_PACKET_SIZE);
GST_WRITE_UINT64_BE (ret, packet->local_time);
GST_WRITE_UINT64_BE (ret + sizeof (GstClockTime), packet->remote_time);
return ret;
}
/**
* gst_net_time_packet_receive:
* @fd: a file descriptor created by socket(2)
* @addr: a pointer to a sockaddr to hold the address of the sender
* @len: a pointer to the size of the data pointed to by @addr
*
* Receives a #GstNetTimePacket over a socket. Handles interrupted system calls,
* but otherwise returns NULL on error. See recvfrom(2) for more information on
* how to interpret @sockaddr.
*
* MT safe. Caller owns return value (g_free to free).
*
* Returns: The new #GstNetTimePacket.
*/
GstNetTimePacket *
gst_net_time_packet_receive (gint fd, struct sockaddr * addr, socklen_t * len)
{
guint8 buffer[GST_NET_TIME_PACKET_SIZE];
gint ret;
while (TRUE) {
#ifdef G_OS_WIN32
ret = recvfrom (fd, (char *) buffer, GST_NET_TIME_PACKET_SIZE,
#else
ret = recvfrom (fd, buffer, GST_NET_TIME_PACKET_SIZE,
#endif
0, (struct sockaddr *) addr, len);
if (ret < 0) {
if (errno != EAGAIN && errno != EINTR)
goto receive_error;
else
continue;
} else if (ret < GST_NET_TIME_PACKET_SIZE) {
goto short_packet;
} else {
return gst_net_time_packet_new (buffer);
}
}
receive_error:
{
GST_DEBUG ("receive error %d: %s (%d)", ret, g_strerror (errno), errno);
return NULL;
}
short_packet:
{
GST_DEBUG ("someone sent us a short packet (%d < %d)",
ret, GST_NET_TIME_PACKET_SIZE);
return NULL;
}
}
/**
* gst_net_time_packet_send:
* @packet: the #GstNetTimePacket
* @fd: a file descriptor created by socket(2)
* @addr: a pointer to a sockaddr to hold the address of the sender
* @len: the size of the data pointed to by @addr
*
* Sends a #GstNetTimePacket over a socket. Essentially a thin wrapper around
* sendto(2) and gst_net_time_packet_serialize().
*
* MT safe.
*
* Returns: The return value of sendto(2).
*/
gint
gst_net_time_packet_send (const GstNetTimePacket * packet, gint fd,
struct sockaddr * addr, socklen_t len)
{
#if defined __CYGWIN__
gint fdflags;
#elif defined G_OS_WIN32
gulong flags;
#endif
guint8 *buffer;
gint ret, send_flags;
g_return_val_if_fail (packet != NULL, -EINVAL);
#ifdef __CYGWIN__
send_flags = 0;
fdflags = fcntl (fd, F_GETFL);
fcntl (fd, F_SETFL, fdflags | O_NONBLOCK);
#elif defined G_OS_WIN32
flags = 1;
send_flags = 0;
#else
send_flags = MSG_DONTWAIT;
#endif
buffer = gst_net_time_packet_serialize (packet);
#ifdef G_OS_WIN32
ioctlsocket (fd, FIONBIO, &flags); /* Set nonblocking mode */
ret =
sendto (fd, (char *) buffer, GST_NET_TIME_PACKET_SIZE, send_flags, addr,
len);
#else
ret = sendto (fd, buffer, GST_NET_TIME_PACKET_SIZE, send_flags, addr, len);
#endif
#ifdef __CYGWIN__
fcntl (fd, F_SETFL, fdflags);
#endif
g_free (buffer);
return ret;
}
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