/* GStreamer

 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>

 * Copyright (C) <2004> Thomas Vander Stichele <thomas at apestaart dot org>

 * Copyright (C) 2006 Wim Taymans <wim at fluendo dot 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., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

/**

 * SECTION:element-multifdsink

 * @title: multifdsink

 * @see_also: tcpserversink

 *

 * This plugin writes incoming data to a set of file descriptors. The

 * file descriptors can be added to multifdsink by emitting the #GstMultiFdSink::add signal.

 * For each descriptor added, the #GstMultiFdSink::client-added signal will be called.

 *

 * The multifdsink element needs to be set into READY, PAUSED or PLAYING state

 * before operations such as adding clients are possible.

 *

 * A client can also be added with the #GstMultiFdSink::add-full signal

 * that allows for more control over what and how much data a client

 * initially receives.

 *

 * Clients can be removed from multifdsink by emitting the #GstMultiFdSink::remove signal. For

 * each descriptor removed, the #GstMultiFdSink::client-removed signal will be called. The

 * #GstMultiFdSink::client-removed signal can also be fired when multifdsink decides that a

 * client is not active anymore or, depending on the value of the

 * #GstMultiFdSink:recover-policy property, if the client is reading too slowly.

 * In all cases, multifdsink will never close a file descriptor itself.

 * The user of multifdsink is responsible for closing all file descriptors.

 * This can for example be done in response to the #GstMultiFdSink::client-fd-removed signal.

 * Note that multifdsink still has a reference to the file descriptor when the

 * #GstMultiFdSink::client-removed signal is emitted, so that "get-stats" can be performed on

 * the descriptor; it is therefore not safe to close the file descriptor in

 * the #GstMultiFdSink::client-removed signal handler, and you should use the

 * #GstMultiFdSink::client-fd-removed signal to safely close the fd.

 *

 * Multifdsink internally keeps a queue of the incoming buffers and uses a

 * separate thread to send the buffers to the clients. This ensures that no

 * client write can block the pipeline and that clients can read with different

 * speeds.

 *

 * When adding a client to multifdsink, the #GstMultiFdSink:sync-method property will define

 * which buffer in the queued buffers will be sent first to the client. Clients

 * can be sent the most recent buffer (which might not be decodable by the

 * client if it is not a keyframe), the next keyframe received in

 * multifdsink (which can take some time depending on the keyframe rate), or the

 * last received keyframe (which will cause a simple burst-on-connect).

 * Multifdsink will always keep at least one keyframe in its internal buffers

 * when the sync-mode is set to latest-keyframe.

 *

 * There are additional values for the #GstMultiFdSink:sync-method

 * property to allow finer control over burst-on-connect behaviour. By selecting

 * the 'burst' method a minimum burst size can be chosen, 'burst-keyframe'

 * additionally requires that the burst begin with a keyframe, and

 * 'burst-with-keyframe' attempts to burst beginning with a keyframe, but will

 * prefer a minimum burst size even if it requires not starting with a keyframe.

 *

 * Multifdsink can be instructed to keep at least a minimum amount of data

 * expressed in time or byte units in its internal queues with the

 * #GstMultiFdSink:time-min and #GstMultiFdSink:bytes-min properties respectively.

 * These properties are useful if the application adds clients with the

 * #GstMultiFdSink::add-full signal to make sure that a burst connect can

 * actually be honored.

 *

 * When streaming data, clients are allowed to read at a different rate than

 * the rate at which multifdsink receives data. If the client is reading too

 * fast, no data will be send to the client until multifdsink receives more

 * data. If the client, however, reads too slowly, data for that client will be

 * queued up in multifdsink. Two properties control the amount of data

 * (buffers) that is queued in multifdsink: #GstMultiFdSink:buffers-max and

 * #GstMultiFdSink:buffers-soft-max. A client that falls behind by

 * #GstMultiFdSink:buffers-max is removed from multifdsink forcibly.

 *

 * A client with a lag of at least #GstMultiFdSink:buffers-soft-max enters the recovery

 * procedure which is controlled with the #GstMultiFdSink:recover-policy property.

 * A recover policy of NONE will do nothing, RESYNC_LATEST will send the most recently

 * received buffer as the next buffer for the client, RESYNC_SOFT_LIMIT

 * positions the client to the soft limit in the buffer queue and

 * RESYNC_KEYFRAME positions the client at the most recent keyframe in the

 * buffer queue.

 *

 * multifdsink will by default synchronize on the clock before serving the

 * buffers to the clients. This behaviour can be disabled by setting the sync

 * property to FALSE. Multifdsink will by default not do QoS and will never

 * drop late buffers.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gst/gst-i18n-plugin.h>

#include <sys/ioctl.h>

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#include <string.h>

#include <fcntl.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <sys/stat.h>

#include <netinet/in.h>

#ifdef HAVE_FIONREAD_IN_SYS_FILIO

#include <sys/filio.h>

#endif

#include "gstmultifdsink.h"

#define NOT_IMPLEMENTED 0

GST_DEBUG_CATEGORY_STATIC (multifdsink_debug);

#define GST_CAT_DEFAULT (multifdsink_debug)

/* MultiFdSink signals and args */

enum

{

  /* methods */

  SIGNAL_ADD,

  SIGNAL_ADD_BURST,

  SIGNAL_REMOVE,

  SIGNAL_REMOVE_FLUSH,

  SIGNAL_GET_STATS,

  /* signals */

  SIGNAL_CLIENT_ADDED,

  SIGNAL_CLIENT_REMOVED,

  SIGNAL_CLIENT_FD_REMOVED,

  LAST_SIGNAL

};

/* this is really arbitrarily chosen */

#define DEFAULT_HANDLE_READ             TRUE

enum

{

  PROP_0,

  PROP_HANDLE_READ

};

static void gst_multi_fd_sink_stop_pre (GstMultiHandleSink * mhsink);

static void gst_multi_fd_sink_stop_post (GstMultiHandleSink * mhsink);

static gboolean gst_multi_fd_sink_start_pre (GstMultiHandleSink * mhsink);

static gpointer gst_multi_fd_sink_thread (GstMultiHandleSink * mhsink);

static void gst_multi_fd_sink_add (GstMultiFdSink * sink, int fd);

static void gst_multi_fd_sink_add_full (GstMultiFdSink * sink, int fd,

    GstSyncMethod sync, GstFormat min_format, guint64 min_value,

    GstFormat max_format, guint64 max_value);

static void gst_multi_fd_sink_remove (GstMultiFdSink * sink, int fd);

static void gst_multi_fd_sink_remove_flush (GstMultiFdSink * sink, int fd);

static GstStructure *gst_multi_fd_sink_get_stats (GstMultiFdSink * sink,

    int fd);

static void gst_multi_fd_sink_emit_client_added (GstMultiHandleSink * mhsink,

    GstMultiSinkHandle handle);

static void gst_multi_fd_sink_emit_client_removed (GstMultiHandleSink * mhsink,

    GstMultiSinkHandle handle, GstClientStatus status);

static GstMultiHandleClient *gst_multi_fd_sink_new_client (GstMultiHandleSink *

    mhsink, GstMultiSinkHandle handle, GstSyncMethod sync_method);

static void gst_multi_fd_sink_client_free (GstMultiHandleSink * m,

    GstMultiHandleClient * client);

static int gst_multi_fd_sink_client_get_fd (GstMultiHandleClient * client);

static void gst_multi_fd_sink_handle_debug (GstMultiSinkHandle handle,

    gchar debug[30]);

static gpointer gst_multi_fd_sink_handle_hash_key (GstMultiSinkHandle handle);

static void gst_multi_fd_sink_hash_adding (GstMultiHandleSink * mhsink,

    GstMultiHandleClient * mhclient);

static void gst_multi_fd_sink_hash_removing (GstMultiHandleSink * mhsink,

    GstMultiHandleClient * mhclient);

static void gst_multi_fd_sink_hash_changed (GstMultiHandleSink * mhsink);

static void gst_multi_fd_sink_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec);

static void gst_multi_fd_sink_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec);

#define gst_multi_fd_sink_parent_class parent_class

G_DEFINE_TYPE (GstMultiFdSink, gst_multi_fd_sink, GST_TYPE_MULTI_HANDLE_SINK);

static guint gst_multi_fd_sink_signals[LAST_SIGNAL] = { 0 };

static void

gst_multi_fd_sink_class_init (GstMultiFdSinkClass * klass)

{

  GObjectClass *gobject_class;

  GstElementClass *gstelement_class;

  GstMultiHandleSinkClass *gstmultihandlesink_class;

  gobject_class = (GObjectClass *) klass;

  gstelement_class = (GstElementClass *) klass;

  gstmultihandlesink_class = (GstMultiHandleSinkClass *) klass;

  gobject_class->set_property = gst_multi_fd_sink_set_property;

  gobject_class->get_property = gst_multi_fd_sink_get_property;

  /**

   * GstMultiFdSink::handle-read

   *

   * Handle read requests from clients and discard the data.

   */

  g_object_class_install_property (gobject_class, PROP_HANDLE_READ,

      g_param_spec_boolean ("handle-read", "Handle Read",

          "Handle client reads and discard the data",

          DEFAULT_HANDLE_READ, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**

   * GstMultiFdSink::add:

   * @gstmultifdsink: the multifdsink element to emit this signal on

   * @fd:             the file descriptor to add to multifdsink

   *

   * Hand the given open file descriptor to multifdsink to write to.

   */

  gst_multi_fd_sink_signals[SIGNAL_ADD] =

      g_signal_new ("add", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,

      G_STRUCT_OFFSET (GstMultiFdSinkClass, add), NULL, NULL,

      g_cclosure_marshal_generic, G_TYPE_NONE, 1, G_TYPE_INT);

  /**

   * GstMultiFdSink::add-full:

   * @gstmultifdsink:  the multifdsink element to emit this signal on

   * @fd:              the file descriptor to add to multifdsink

   * @sync:            the sync method to use

   * @format_min:      the format of @value_min

   * @value_min:       the minimum amount of data to burst expressed in

   *                   @format_min units.

   * @format_max:      the format of @value_max

   * @value_max:       the maximum amount of data to burst expressed in

   *                   @format_max units.

   *

   * Hand the given open file descriptor to multifdsink to write to and

   * specify the burst parameters for the new connection.

   */

  gst_multi_fd_sink_signals[SIGNAL_ADD_BURST] =

      g_signal_new ("add-full", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,

      G_STRUCT_OFFSET (GstMultiFdSinkClass, add_full), NULL, NULL,

      g_cclosure_marshal_generic, G_TYPE_NONE, 6,

      G_TYPE_INT, GST_TYPE_SYNC_METHOD, GST_TYPE_FORMAT, G_TYPE_UINT64,

      GST_TYPE_FORMAT, G_TYPE_UINT64);

  /**

   * GstMultiFdSink::remove:

   * @gstmultifdsink: the multifdsink element to emit this signal on

   * @fd:             the file descriptor to remove from multifdsink

   *

   * Remove the given open file descriptor from multifdsink.

   */

  gst_multi_fd_sink_signals[SIGNAL_REMOVE] =

      g_signal_new ("remove", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,

      G_STRUCT_OFFSET (GstMultiFdSinkClass, remove), NULL, NULL,

      g_cclosure_marshal_generic, G_TYPE_NONE, 1, G_TYPE_INT);

  /**

   * GstMultiFdSink::remove-flush:

   * @gstmultifdsink: the multifdsink element to emit this signal on

   * @fd:             the file descriptor to remove from multifdsink

   *

   * Remove the given open file descriptor from multifdsink after flushing all

   * the pending data to the fd.

   */

  gst_multi_fd_sink_signals[SIGNAL_REMOVE_FLUSH] =

      g_signal_new ("remove-flush", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,

      G_STRUCT_OFFSET (GstMultiFdSinkClass, remove_flush), NULL, NULL,

      g_cclosure_marshal_generic, G_TYPE_NONE, 1, G_TYPE_INT);

  /**

   * GstMultiFdSink::get-stats:

   * @gstmultifdsink: the multifdsink element to emit this signal on

   * @fd:             the file descriptor to get stats of from multifdsink

   *

   * Get statistics about @fd. This function returns a #GstStructure to ease

   * automatic wrapping for bindings.

   *

   * Returns: a #GstStructure with the statistics. The structures

   *     contains guint64 values that represent respectively: total

   *     number of bytes sent (bytes-sent), time when the client was

   *     added (connect-time), time when the client was

   *     disconnected/removed (disconnect-time), time the client

   *     is/was active (connect-duration), last activity time (in

   *     epoch seconds) (last-activity-time), number of buffers

   *     dropped (buffers-dropped), the timestamp of the first buffer

   *     (first-buffer-ts) and of the last buffer (last-buffer-ts).

   *     All times are expressed in nanoseconds (GstClockTime).  The

   *     structure can be empty if the client was not found.

   */

  gst_multi_fd_sink_signals[SIGNAL_GET_STATS] =

      g_signal_new ("get-stats", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,

      G_STRUCT_OFFSET (GstMultiFdSinkClass, get_stats), NULL, NULL,

      g_cclosure_marshal_generic, GST_TYPE_STRUCTURE, 1, G_TYPE_INT);

  /**

   * GstMultiFdSink::client-added:

   * @gstmultifdsink: the multifdsink element that emitted this signal

   * @fd:             the file descriptor that was added to multifdsink

   *

   * The given file descriptor was added to multifdsink. This signal will

   * be emitted from the streaming thread so application should be prepared

   * for that.

   */

  gst_multi_fd_sink_signals[SIGNAL_CLIENT_ADDED] =

      g_signal_new ("client-added", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST, 0, NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE,

      1, G_TYPE_INT);

  /**

   * GstMultiFdSink::client-removed:

   * @gstmultifdsink: the multifdsink element that emitted this signal

   * @fd:             the file descriptor that is to be removed from multifdsink

   * @status:         the reason why the client was removed

   *

   * The given file descriptor is about to be removed from multifdsink. This

   * signal will be emitted from the streaming thread so applications should

   * be prepared for that.

   *

   * @gstmultifdsink still holds a handle to @fd so it is possible to call

   * the get-stats signal from this callback. For the same reason it is

   * not safe to close() and reuse @fd in this callback.

   */

  gst_multi_fd_sink_signals[SIGNAL_CLIENT_REMOVED] =

      g_signal_new ("client-removed", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST, 0, NULL, NULL, g_cclosure_marshal_generic,

      G_TYPE_NONE, 2, G_TYPE_INT, GST_TYPE_CLIENT_STATUS);

  /**

   * GstMultiFdSink::client-fd-removed:

   * @gstmultifdsink: the multifdsink element that emitted this signal

   * @fd:             the file descriptor that was removed from multifdsink

   *

   * The given file descriptor was removed from multifdsink. This signal will

   * be emitted from the streaming thread so applications should be prepared

   * for that.

   *

   * In this callback, @gstmultifdsink has removed all the information

   * associated with @fd and it is therefore not possible to call get-stats

   * with @fd. It is however safe to close() and reuse @fd in the callback.

   */

  gst_multi_fd_sink_signals[SIGNAL_CLIENT_FD_REMOVED] =

      g_signal_new ("client-fd-removed", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST, 0, NULL, NULL, g_cclosure_marshal_generic,

      G_TYPE_NONE, 1, G_TYPE_INT);

  gst_element_class_set_static_metadata (gstelement_class,

      "Multi filedescriptor sink", "Sink/Network",

      "Send data to multiple filedescriptors",

      "Thomas Vander Stichele <thomas at apestaart dot org>, "

      "Wim Taymans <wim@fluendo.com>");

  klass->add = GST_DEBUG_FUNCPTR (gst_multi_fd_sink_add);

  klass->add_full = GST_DEBUG_FUNCPTR (gst_multi_fd_sink_add_full);

  klass->remove = GST_DEBUG_FUNCPTR (gst_multi_fd_sink_remove);

  klass->remove_flush = GST_DEBUG_FUNCPTR (gst_multi_fd_sink_remove_flush);

  klass->get_stats = GST_DEBUG_FUNCPTR (gst_multi_fd_sink_get_stats);

  gstmultihandlesink_class->emit_client_added =

      gst_multi_fd_sink_emit_client_added;

  gstmultihandlesink_class->emit_client_removed =

      gst_multi_fd_sink_emit_client_removed;

  gstmultihandlesink_class->stop_pre =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_stop_pre);

  gstmultihandlesink_class->stop_post =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_stop_post);

  gstmultihandlesink_class->start_pre =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_start_pre);

  gstmultihandlesink_class->thread =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_thread);

  gstmultihandlesink_class->new_client =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_new_client);

  gstmultihandlesink_class->client_free = gst_multi_fd_sink_client_free;

  gstmultihandlesink_class->client_get_fd =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_client_get_fd);

  gstmultihandlesink_class->handle_debug =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_handle_debug);

  gstmultihandlesink_class->handle_hash_key =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_handle_hash_key);

  gstmultihandlesink_class->hash_changed =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_hash_changed);

  gstmultihandlesink_class->hash_adding =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_hash_adding);

  gstmultihandlesink_class->hash_removing =

      GST_DEBUG_FUNCPTR (gst_multi_fd_sink_hash_removing);

  GST_DEBUG_CATEGORY_INIT (multifdsink_debug, "multifdsink", 0, "FD sink");

}

static void

gst_multi_fd_sink_init (GstMultiFdSink * this)

{

  GstMultiHandleSink *mhsink = GST_MULTI_HANDLE_SINK (this);

  mhsink->handle_hash = g_hash_table_new (g_direct_hash, g_direct_equal);

  this->handle_read = DEFAULT_HANDLE_READ;

}

/* methods to emit signals */

static void

gst_multi_fd_sink_emit_client_added (GstMultiHandleSink * mhsink,

    GstMultiSinkHandle handle)

{

  g_signal_emit (mhsink, gst_multi_fd_sink_signals[SIGNAL_CLIENT_ADDED], 0,

      handle.fd);

}

static void

gst_multi_fd_sink_emit_client_removed (GstMultiHandleSink * mhsink,

    GstMultiSinkHandle handle, GstClientStatus status)

{

  g_signal_emit (mhsink, gst_multi_fd_sink_signals[SIGNAL_CLIENT_REMOVED], 0,

      handle.fd, status);

}

static void

gst_multi_fd_sink_client_free (GstMultiHandleSink * mhsink,

    GstMultiHandleClient * client)

{

  g_signal_emit (mhsink, gst_multi_fd_sink_signals[SIGNAL_CLIENT_FD_REMOVED],

      0, client->handle.fd);

}

/* action signals */

static void

gst_multi_fd_sink_add (GstMultiFdSink * sink, int fd)

{

  GstMultiSinkHandle handle;

  handle.fd = fd;

  gst_multi_handle_sink_add (GST_MULTI_HANDLE_SINK_CAST (sink), handle);

}

static void

gst_multi_fd_sink_add_full (GstMultiFdSink * sink, int fd,

    GstSyncMethod sync, GstFormat min_format, guint64 min_value,

    GstFormat max_format, guint64 max_value)

{

  GstMultiSinkHandle handle;

  handle.fd = fd;

  gst_multi_handle_sink_add_full (GST_MULTI_HANDLE_SINK_CAST (sink), handle,

      sync, min_format, min_value, max_format, max_value);

}

static void

gst_multi_fd_sink_remove (GstMultiFdSink * sink, int fd)

{

  GstMultiSinkHandle handle;

  handle.fd = fd;

  gst_multi_handle_sink_remove (GST_MULTI_HANDLE_SINK_CAST (sink), handle);

}

static void

gst_multi_fd_sink_remove_flush (GstMultiFdSink * sink, int fd)

{

  GstMultiSinkHandle handle;

  handle.fd = fd;

  gst_multi_handle_sink_remove_flush (GST_MULTI_HANDLE_SINK_CAST (sink),

      handle);

}

static GstStructure *

gst_multi_fd_sink_get_stats (GstMultiFdSink * sink, int fd)

{

  GstMultiSinkHandle handle;

  handle.fd = fd;

  return gst_multi_handle_sink_get_stats (GST_MULTI_HANDLE_SINK_CAST (sink),

      handle);

}

/* vfuncs */

static GstMultiHandleClient *

gst_multi_fd_sink_new_client (GstMultiHandleSink * mhsink,

    GstMultiSinkHandle handle, GstSyncMethod sync_method)

{

  struct stat statbuf;

  GstTCPClient *client;

  GstMultiHandleClient *mhclient;

  GstMultiFdSink *sink = GST_MULTI_FD_SINK (mhsink);

  GstMultiHandleSinkClass *mhsinkclass =

      GST_MULTI_HANDLE_SINK_GET_CLASS (mhsink);

  /* create client datastructure */

  client = g_new0 (GstTCPClient, 1);

  mhclient = (GstMultiHandleClient *) client;

  mhclient->handle = handle;

  gst_poll_fd_init (&client->gfd);

  client->gfd.fd = mhclient->handle.fd;

  gst_multi_handle_sink_client_init (mhclient, sync_method);

  mhsinkclass->handle_debug (handle, mhclient->debug);

  /* set the socket to non blocking */

  if (fcntl (handle.fd, F_SETFL, O_NONBLOCK) < 0) {

    GST_ERROR_OBJECT (mhsink, "failed to make socket %s non-blocking: %s",

        mhclient->debug, g_strerror (errno));

  }

  /* we always read from a client */

  gst_poll_add_fd (sink->fdset, &client->gfd);

  /* we don't try to read from write only fds */

  if (sink->handle_read) {

    gint flags;

    flags = fcntl (handle.fd, F_GETFL, 0);

    if ((flags & O_ACCMODE) != O_WRONLY) {

      gst_poll_fd_ctl_read (sink->fdset, &client->gfd, TRUE);

    }

  }

  /* figure out the mode, can't use send() for non sockets */

  if (fstat (handle.fd, &statbuf) == 0 && S_ISSOCK (statbuf.st_mode)) {

    client->is_socket = TRUE;

    gst_multi_handle_sink_setup_dscp_client (mhsink, mhclient);

  }

  return mhclient;

}

static int

gst_multi_fd_sink_client_get_fd (GstMultiHandleClient * client)

{

  GstTCPClient *tclient = (GstTCPClient *) client;

  return tclient->gfd.fd;

}

static void

gst_multi_fd_sink_handle_debug (GstMultiSinkHandle handle, gchar debug[30])

{

  g_snprintf (debug, 30, "[fd %5d]", handle.fd);

}

static gpointer

gst_multi_fd_sink_handle_hash_key (GstMultiSinkHandle handle)

{

  return GINT_TO_POINTER (handle.fd);

}

static void

gst_multi_fd_sink_hash_changed (GstMultiHandleSink * mhsink)

{

  GstMultiFdSink *sink = GST_MULTI_FD_SINK (mhsink);

  gst_poll_restart (sink->fdset);

}

/* handle a read on a client fd,

 * which either indicates a close or should be ignored

 * returns FALSE if some error occured or the client closed. */

static gboolean

gst_multi_fd_sink_handle_client_read (GstMultiFdSink * sink,

    GstTCPClient * client)

{

  int avail, fd;

  gboolean ret;

  GstMultiHandleClient *mhclient = (GstMultiHandleClient *) client;

  fd = client->gfd.fd;

  if (ioctl (fd, FIONREAD, &avail) < 0)

    goto ioctl_failed;

  GST_DEBUG_OBJECT (sink, "%s select reports client read of %d bytes",

      mhclient->debug, avail);

  ret = TRUE;

  if (avail == 0) {

    /* client sent close, so remove it */

    GST_DEBUG_OBJECT (sink, "%s client asked for close, removing",

        mhclient->debug);

    mhclient->status = GST_CLIENT_STATUS_CLOSED;

    ret = FALSE;

  } else if (avail < 0) {

    GST_WARNING_OBJECT (sink, "%s avail < 0, removing", mhclient->debug);

    mhclient->status = GST_CLIENT_STATUS_ERROR;

    ret = FALSE;

  } else {

    guint8 dummy[512];

    gint nread;

    /* just Read 'n' Drop, could also just drop the client as it's not supposed

     * to write to us except for closing the socket, I guess it's because we

     * like to listen to our customers. */

    do {

      /* this is the maximum we can read */

      gint to_read = MIN (avail, 512);

      GST_DEBUG_OBJECT (sink, "%s client wants us to read %d bytes",

          mhclient->debug, to_read);

      nread = read (fd, dummy, to_read);

      if (nread < -1) {

        GST_WARNING_OBJECT (sink, "%s could not read %d bytes: %s (%d)",

            mhclient->debug, to_read, g_strerror (errno), errno);

        mhclient->status = GST_CLIENT_STATUS_ERROR;

        ret = FALSE;

        break;

      } else if (nread == 0) {

        GST_WARNING_OBJECT (sink, "%s 0 bytes in read, removing",

            mhclient->debug);

        mhclient->status = GST_CLIENT_STATUS_ERROR;

        ret = FALSE;

        break;

      }

      avail -= nread;

    }

    while (avail > 0);

  }

  return ret;

  /* ERRORS */

ioctl_failed:

  {

    GST_WARNING_OBJECT (sink, "%s ioctl failed: %s (%d)",

        mhclient->debug, g_strerror (errno), errno);

    mhclient->status = GST_CLIENT_STATUS_ERROR;

    return FALSE;

  }

}

/* Handle a write on a client,

 * which indicates a read request from a client.

 *

 * For each client we maintain a queue of GstBuffers that contain the raw bytes

 * we need to send to the client.

 *

 * We first check to see if we need to send streamheaders. If so, we queue them.

 *

 * Then we run into the main loop that tries to send as many buffers as

 * possible. It will first exhaust the mhclient->sending queue and if the queue

 * is empty, it will pick a buffer from the global queue.

 *

 * Sending the buffers from the mhclient->sending queue is basically writing

 * the bytes to the socket and maintaining a count of the bytes that were

 * sent. When the buffer is completely sent, it is removed from the

 * mhclient->sending queue and we try to pick a new buffer for sending.

 *

 * When the sending returns a partial buffer we stop sending more data as

 * the next send operation could block.

 *

 * This functions returns FALSE if some error occured.

 */

static gboolean

gst_multi_fd_sink_handle_client_write (GstMultiFdSink * sink,

    GstTCPClient * client)

{

  gboolean more;

  gboolean flushing;

  GstClockTime now;

  GTimeVal nowtv;

  GstMultiHandleSink *mhsink = GST_MULTI_HANDLE_SINK (sink);

  GstMultiHandleSinkClass *mhsinkclass =

      GST_MULTI_HANDLE_SINK_GET_CLASS (mhsink);

  GstMultiHandleClient *mhclient = (GstMultiHandleClient *) client;

  int fd = mhclient->handle.fd;

  flushing = mhclient->status == GST_CLIENT_STATUS_FLUSHING;

  more = TRUE;

  do {

    gint maxsize;

    g_get_current_time (&nowtv);

    now = GST_TIMEVAL_TO_TIME (nowtv);

    if (!mhclient->sending) {

      /* client is not working on a buffer */

      if (mhclient->bufpos == -1) {

        /* client is too fast, remove from write queue until new buffer is

         * available */

        /* FIXME: specific */

        gst_poll_fd_ctl_write (sink->fdset, &client->gfd, FALSE);

        /* if we flushed out all of the client buffers, we can stop */

        if (mhclient->flushcount == 0)

          goto flushed;

        return TRUE;

      } else {

        /* client can pick a buffer from the global queue */

        GstBuffer *buf;

        GstClockTime timestamp;

        /* for new connections, we need to find a good spot in the

         * bufqueue to start streaming from */

        if (mhclient->new_connection && !flushing) {

          gint position =

              gst_multi_handle_sink_new_client_position (mhsink, mhclient);

          if (position >= 0) {

            /* we got a valid spot in the queue */

            mhclient->new_connection = FALSE;

            mhclient->bufpos = position;

          } else {

            /* cannot send data to this client yet */

            /* FIXME: specific */

            gst_poll_fd_ctl_write (sink->fdset, &client->gfd, FALSE);

            return TRUE;

          }

        }

        /* we flushed all remaining buffers, no need to get a new one */

        if (mhclient->flushcount == 0)

          goto flushed;

        /* grab buffer */

        buf = g_array_index (mhsink->bufqueue, GstBuffer *, mhclient->bufpos);

        mhclient->bufpos--;

        /* update stats */

        timestamp = GST_BUFFER_TIMESTAMP (buf);

        if (mhclient->first_buffer_ts == GST_CLOCK_TIME_NONE)

          mhclient->first_buffer_ts = timestamp;

        if (timestamp != -1)

          mhclient->last_buffer_ts = timestamp;

        /* decrease flushcount */

        if (mhclient->flushcount != -1)

          mhclient->flushcount--;

        GST_LOG_OBJECT (sink, "%s client %p at position %d",

            mhclient->debug, client, mhclient->bufpos);

        /* queueing a buffer will ref it */

        mhsinkclass->client_queue_buffer (mhsink, mhclient, buf);

        /* need to start from the first byte for this new buffer */

        mhclient->bufoffset = 0;

      }

    }

    /* see if we need to send something */

    if (mhclient->sending) {

      ssize_t wrote;

      GstBuffer *head;

      GstMapInfo info;

      guint8 *data;

      /* pick first buffer from list */

      head = GST_BUFFER (mhclient->sending->data);

      if (!gst_buffer_map (head, &info, GST_MAP_READ))

        g_return_val_if_reached (FALSE);

      data = info.data;

      maxsize = info.size - mhclient->bufoffset;

      /* FIXME: specific */

      /* try to write the complete buffer */

#ifdef MSG_NOSIGNAL

#define FLAGS MSG_NOSIGNAL

#else

#define FLAGS 0

#endif

      if (client->is_socket) {

        wrote = send (fd, data + mhclient->bufoffset, maxsize, FLAGS);

      } else {

        wrote = write (fd, data + mhclient->bufoffset, maxsize);

      }

      gst_buffer_unmap (head, &info;;

      if (wrote < 0) {

        /* hmm error.. */

        if (errno == EAGAIN) {

          /* nothing serious, resource was unavailable, try again later */

          more = FALSE;

        } else if (errno == ECONNRESET) {

          goto connection_reset;

        } else {

          goto write_error;

        }

      } else {

        if (wrote < maxsize) {

          /* partial write means that the client cannot read more and we should

           * stop sending more */

          GST_LOG_OBJECT (sink,

              "partial write on %s of %" G_GSSIZE_FORMAT " bytes",

              mhclient->debug, wrote);

          mhclient->bufoffset += wrote;

          more = FALSE;

        } else {

          /* complete buffer was written, we can proceed to the next one */

          mhclient->sending = g_slist_remove (mhclient->sending, head);

          gst_buffer_unref (head);

          /* make sure we start from byte 0 for the next buffer */

          mhclient->bufoffset = 0;

        }

        /* update stats */

        mhclient->bytes_sent += wrote;

        mhclient->last_activity_time = now;

        mhsink->bytes_served += wrote;

      }

    }

  } while (more);

  return TRUE;

  /* ERRORS */

flushed:

  {

    GST_DEBUG_OBJECT (sink, "%s flushed, removing", mhclient->debug);

    mhclient->status = GST_CLIENT_STATUS_REMOVED;

    return FALSE;

  }

connection_reset:

  {

    GST_DEBUG_OBJECT (sink, "%s connection reset by peer, removing",

        mhclient->debug);

    mhclient->status = GST_CLIENT_STATUS_CLOSED;

    return FALSE;

  }

write_error:

  {

    GST_WARNING_OBJECT (sink,

        "%s could not write, removing client: %s (%d)", mhclient->debug,

        g_strerror (errno), errno);

    mhclient->status = GST_CLIENT_STATUS_ERROR;

    return FALSE;

  }

}

static void

gst_multi_fd_sink_hash_adding (GstMultiHandleSink * mhsink,

    GstMultiHandleClient * mhclient)

{

  GstMultiFdSink *sink = GST_MULTI_FD_SINK (mhsink);

  GstTCPClient *client = (GstTCPClient *) mhclient;

  gst_poll_fd_ctl_write (sink->fdset, &client->gfd, TRUE);

}

static void

gst_multi_fd_sink_hash_removing (GstMultiHandleSink * mhsink,

    GstMultiHandleClient * mhclient)

{

  GstMultiFdSink *sink = GST_MULTI_FD_SINK (mhsink);

  GstTCPClient *client = (GstTCPClient *) mhclient;

  gst_poll_remove_fd (sink->fdset, &client->gfd);

}

/* Handle the clients. Basically does a blocking select for one

 * of the client fds to become read or writable. We also have a

 * filedescriptor to receive commands on that we need to check.

 *

 * After going out of the select call, we read and write to all

 * clients that can do so. Badly behaving clients are put on a

 * garbage list and removed.

 */

static void