modules/access/sdp.c

   1 /*****************************************************************************
   2  * sdp.c: Fake input for sdp:// scheme
   3  *****************************************************************************
   4  * Copyright (C) 2010 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <vlc_common.h>
  26 #include <vlc_plugin.h>
  27 #include <vlc_access.h>
  28
  29 static int Open (vlc_object_t *);
  30
  31 vlc_module_begin ()
  32     set_shortname (N_("SDP"))
  33     set_description (N_("Session Description Protocol"))
  34     set_category (CAT_INPUT)
  35     set_subcategory (SUBCAT_INPUT_ACCESS)
  36
  37     set_capability ("access", 0)
  38     set_callbacks (Open, NULL)
  39     add_shortcut ("sdp")
  40 vlc_module_end()
  41
  42 static ssize_t Read (stream_t *, void *, size_t);
  43 static int Seek (stream_t *, uint64_t);
  44 static int Control (stream_t *, int, va_list);
  45
  46 struct access_sys_t
  47 {
  48     size_t offset;
  49     size_t length;
  50     char   data[];
  51 };
  52
  53 static int Open (vlc_object_t *obj)
  54 {
  55     stream_t *access = (stream_t *)obj;
  56     size_t len = strlen (access->psz_location);
  57
  58     access_sys_t *sys = vlc_malloc(obj, sizeof(*sys) + len);
  59     if (unlikely(sys == NULL))
  60         return VLC_ENOMEM;
  61
  62     /* NOTE: This copy is not really needed. Better safe than sorry. */
  63     sys->offset = 0;
  64     sys->length = len;
  65     memcpy (sys->data, access->psz_location, len);
  66
  67     access->pf_read = Read;
  68     access->pf_block = NULL;
  69     access->pf_seek = Seek;
  70     access->pf_control = Control;
  71     access->p_sys = sys;
  72
  73     return VLC_SUCCESS;
  74 }
  75
  76 static ssize_t Read (stream_t *access, void *buf, size_t len)
  77 {
  78     access_sys_t *sys = access->p_sys;
  79
  80     if (sys->offset >= sys->length)
  81         return 0;
  82
  83     if (len > sys->length - sys->offset)
  84         len = sys->length - sys->offset;
  85     memcpy (buf, sys->data + sys->offset, len);
  86     return len;
  87 }
  88
  89 static int Seek (stream_t *access, uint64_t position)
  90 {
  91     access_sys_t *sys = access->p_sys;
  92
  93     if (position > sys->length)
  94         position = sys->length;
  95
  96     sys->offset = position;
  97     return VLC_SUCCESS;
  98 }
  99
 100 static int Control (stream_t *access, int query, va_list args)
 101 {
 102     access_sys_t *sys = access->p_sys;
 103
 104     switch (query)
 105     {
 106         case STREAM_CAN_SEEK:
 107         case STREAM_CAN_FASTSEEK:
 108         case STREAM_CAN_PAUSE:
 109         case STREAM_CAN_CONTROL_PACE:
 110         {
 111             bool *b = va_arg(args, bool*);
 112             *b = true;
 113             return VLC_SUCCESS;
 114         }
 115
 116         case STREAM_GET_SIZE:
 117             *va_arg(args, uint64_t *) = sys->length;
 118             return VLC_SUCCESS;
 119
 120         case STREAM_GET_PTS_DELAY:
 121         {
 122             int64_t *dp = va_arg(args, int64_t *);
 123             *dp = DEFAULT_PTS_DELAY;
 124             return VLC_SUCCESS;
 125         }
 126
 127         case STREAM_SET_PAUSE_STATE:
 128             return VLC_SUCCESS;
 129     }
 130     return VLC_EGENERIC;
 131 }