mdw@git.distorted.org.uk Git - disorder/blob - plugins/tracklength-gstreamer.c

   1 /*
   2  * This file is part of DisOrder.
   3  * Copyright (C) 2018 Mark Wooding
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 /** @file plugins/tracklength-gstreamer.c
  19  * @brief Plugin to compute track lengths using GStreamer
  20  */
  21 #include "tracklength.h"
  22
  23 #include "speaker-protocol.h"
  24
  25 /* Ugh.  It turns out that libxml tries to define a function called
  26  * `attribute', and it's included by GStreamer for some unimaginable reason.
  27  * So undefine it here.  We'll want GCC attributes for special effects, but
  28  * can take care of ourselves.
  29  */
  30 #undef attribute
  31
  32 #include <glib.h>
  33 #include <gst/gst.h>
  34 #include <gst/pbutils/gstdiscoverer.h>
  35
  36 /* The only application we have for `attribute' is declaring function
  37  * arguments as being unused, because we have a lot of callback functions
  38  * which are meant to comply with an externally defined interface.
  39  */
  40 #ifdef __GNUC__
  41 #  define UNUSED __attribute__((unused))
  42 #endif
  43
  44 #define END ((void *)0)
  45
  46 static GstDiscoverer *disco = 0;
  47
  48 long disorder_tracklength(const char UNUSED *track, const char *path) {
  49   GError *err = 0;
  50   gchar *dir = 0, *abs = 0, *uri = 0;
  51   GstDiscovererInfo *info = 0;
  52   long length = -1;
  53   GstClockTime t;
  54
  55   if (!path) goto end;
  56
  57   if(!disco) {
  58     gst_init(0, 0);
  59     disco = gst_discoverer_new(5*GST_SECOND, &err); if(!disco) goto end;
  60   }
  61
  62   if (g_path_is_absolute(path))
  63     uri = g_filename_to_uri(path, 0, &err);
  64   else {
  65     dir = g_get_current_dir();
  66     abs = g_build_filename(dir, path, END);
  67     uri = g_filename_to_uri(abs, 0, &err);
  68   }
  69   if(!uri) goto end;
  70
  71   info = gst_discoverer_discover_uri(disco, uri, &err); if(!info) goto end;
  72   switch(gst_discoverer_info_get_result(info)) {
  73   case GST_DISCOVERER_OK:
  74     t = gst_discoverer_info_get_duration(info);
  75     length = (t + GST_SECOND/2)/GST_SECOND;
  76     break;
  77   case GST_DISCOVERER_TIMEOUT:
  78     disorder_info("discovery timed out probing `%s'", path);
  79     goto swallow_error;
  80   case GST_DISCOVERER_MISSING_PLUGINS:
  81     disorder_info("unrecognized file `%s' (missing plugins?)", path);
  82     goto swallow_error;
  83   swallow_error:
  84     if(err) { g_error_free(err); err = 0; }
  85     length = 0;
  86     break;
  87   default:
  88     goto end;
  89   }
  90
  91 end:
  92   if(err) {
  93     disorder_error(0, "error probing `%s': %s", path, err->message);
  94     g_error_free(err);
  95   }
  96   if(info) gst_discoverer_info_unref(info);
  97   g_free(dir); g_free(abs); g_free(uri);
  98   return length;
  99 }
 100
 101 #ifdef STANDALONE
 102 int main(int argc, char *argv[]) {
 103   int i;
 104
 105   for(i = 1; i < argc; i++)
 106     printf("%s: %ld\n", argv[i], disorder_tracklength(0, argv[i]));
 107   return (0);
 108 }
 109 #endif
 110
 111 /*
 112 Local Variables:
 113 c-basic-offset:2
 114 comment-column:40
 115 fill-column:79
 116 End:
 117 */