core: refactor MPContext.demuxer field accesses

Whenever the demuxer is accessed to retrieve metadata, use the newly
introduced master_demuxer field instead. If a timeline is used, the
master_demuxer will still refer to the main file, instead to segments.
Instead of mpctx->demuxer->stream, access mpctx->stream; even though
they are the same, the code becomes shorter. For the TV code, introduce
a function get_tvh() to access the TV handle, instead of duplicating the
code all over the place. Often the demuxer field is checked to determine
whether something is currently played; prefer other methods over that.

Note that the code before always accessed the current timeline segment,
and would e.g. read file metadata of the current segment. Now it always
returns metadata for the master file. This may have various wanted and
unwanted effects.

1 files changed, 99 insertions, 94 deletions

diff --git a/command.c b/command.c
index 3b8053c303..edb0e5a77a 100644
--- a/command.c
+++ b/command.c
@@ -296,27 +296,28 @@ static int mp_property_filename(m_option_t *prop, int action, void *arg,
 static int mp_property_demuxer(m_option_t *prop, int action, void *arg,
                                MPContext *mpctx)
 {
-    if (!mpctx->demuxer)
+    struct demuxer *demuxer = mpctx->master_demuxer;
+    if (!demuxer)
         return M_PROPERTY_UNAVAILABLE;
-    return m_property_string_ro(prop, action, arg,
-                                (char *) mpctx->demuxer->desc->name);
+    return m_property_string_ro(prop, action, arg, (char *)demuxer->desc->name);
 }
 
 /// Position in the stream (RW)
 static int mp_property_stream_pos(m_option_t *prop, int action, void *arg,
                                   MPContext *mpctx)
 {
-    if (!mpctx->demuxer || !mpctx->demuxer->stream)
+    struct stream *stream = mpctx->stream;
+    if (!stream)
         return M_PROPERTY_UNAVAILABLE;
     if (!arg)
         return M_PROPERTY_ERROR;
     switch (action) {
     case M_PROPERTY_GET:
-        *(off_t *) arg = stream_tell(mpctx->demuxer->stream);
+        *(off_t *) arg = stream_tell(stream);
         return M_PROPERTY_OK;
     case M_PROPERTY_SET:
         M_PROPERTY_CLAMP(prop, *(off_t *) arg);
-        stream_seek(mpctx->demuxer->stream, *(off_t *) arg);
+        stream_seek(stream, *(off_t *) arg);
         return M_PROPERTY_OK;
     }
     return M_PROPERTY_NOT_IMPLEMENTED;
@@ -326,11 +327,12 @@ static int mp_property_stream_pos(m_option_t *prop, int action, void *arg,
 static int mp_property_stream_start(m_option_t *prop, int action,
                                     void *arg, MPContext *mpctx)
 {
-    if (!mpctx->demuxer || !mpctx->demuxer->stream)
+    struct stream *stream = mpctx->stream;
+    if (!stream)
         return M_PROPERTY_UNAVAILABLE;
     switch (action) {
     case M_PROPERTY_GET:
-        *(off_t *) arg = mpctx->demuxer->stream->start_pos;
+        *(off_t *) arg = stream->start_pos;
         return M_PROPERTY_OK;
     }
     return M_PROPERTY_NOT_IMPLEMENTED;
@@ -340,11 +342,12 @@ static int mp_property_stream_start(m_option_t *prop, int action,
 static int mp_property_stream_end(m_option_t *prop, int action, void *arg,
                                   MPContext *mpctx)
 {
-    if (!mpctx->demuxer || !mpctx->demuxer->stream)
+    struct stream *stream = mpctx->stream;
+    if (!stream)
         return M_PROPERTY_UNAVAILABLE;
     switch (action) {
     case M_PROPERTY_GET:
-        *(off_t *) arg = mpctx->demuxer->stream->end_pos;
+        *(off_t *) arg = stream->end_pos;
         return M_PROPERTY_OK;
     }
     return M_PROPERTY_NOT_IMPLEMENTED;
@@ -354,12 +357,12 @@ static int mp_property_stream_end(m_option_t *prop, int action, void *arg,
 static int mp_property_stream_length(m_option_t *prop, int action,
                                      void *arg, MPContext *mpctx)
 {
-    if (!mpctx->demuxer || !mpctx->demuxer->stream)
+    struct stream *stream = mpctx->stream;
+    if (!stream)
         return M_PROPERTY_UNAVAILABLE;
     switch (action) {
     case M_PROPERTY_GET:
-        *(off_t *) arg =
-            mpctx->demuxer->stream->end_pos - mpctx->demuxer->stream->start_pos;
+        *(off_t *) arg = stream->end_pos - stream->start_pos;
         return M_PROPERTY_OK;
     }
     return M_PROPERTY_NOT_IMPLEMENTED;
@@ -369,10 +372,14 @@ static int mp_property_stream_length(m_option_t *prop, int action,
 static int mp_property_stream_time_pos(m_option_t *prop, int action,
                                        void *arg, MPContext *mpctx)
 {
-    if (!mpctx->demuxer || mpctx->demuxer->stream_pts == MP_NOPTS_VALUE)
+    struct demuxer *demuxer = mpctx->demuxer;
+    if (!demuxer)
+        return M_PROPERTY_UNAVAILABLE;
+    double pts = demuxer->stream_pts;
+    if (pts == MP_NOPTS_VALUE)
         return M_PROPERTY_UNAVAILABLE;
 
-    return m_property_time_ro(prop, action, arg, mpctx->demuxer->stream_pts);
+    return m_property_time_ro(prop, action, arg, pts);
 }
 
 
@@ -382,8 +389,7 @@ static int mp_property_length(m_option_t *prop, int action, void *arg,
 {
     double len;
 
-    if (!mpctx->demuxer ||
-        !(int) (len = get_time_length(mpctx)))
+    if (!(int) (len = get_time_length(mpctx)))
         return M_PROPERTY_UNAVAILABLE;
 
     return m_property_time_ro(prop, action, arg, len);
@@ -395,7 +401,7 @@ static int mp_property_percent_pos(m_option_t *prop, int action,
 {
     int pos;
 
-    if (!mpctx->demuxer)
+    if (!mpctx->num_sources)
         return M_PROPERTY_UNAVAILABLE;
 
     switch (action) {
@@ -424,7 +430,7 @@ static int mp_property_percent_pos(m_option_t *prop, int action,
 static int mp_property_time_pos(m_option_t *prop, int action,
                                 void *arg, MPContext *mpctx)
 {
-    if (!(mpctx->sh_video || mpctx->sh_audio))
+    if (!mpctx->num_sources)
         return M_PROPERTY_UNAVAILABLE;
 
     switch (action) {
@@ -448,12 +454,10 @@ static int mp_property_chapter(m_option_t *prop, int action, void *arg,
                                MPContext *mpctx)
 {
     struct MPOpts *opts = &mpctx->opts;
-    int chapter = -1;
     int step_all;
     char *chapter_name = NULL;
 
-    if (mpctx->demuxer)
-        chapter = get_current_chapter(mpctx);
+    int chapter = get_current_chapter(mpctx);
     if (chapter < -1)
         return M_PROPERTY_UNAVAILABLE;
 
@@ -514,18 +518,20 @@ static int mp_property_chapter(m_option_t *prop, int action, void *arg,
 static int mp_property_titles(m_option_t *prop, int action, void *arg,
                               MPContext *mpctx)
 {
-    if (!mpctx->demuxer)
+    struct demuxer *demuxer = mpctx->master_demuxer;
+    if (!demuxer)
         return M_PROPERTY_UNAVAILABLE;
-    if (mpctx->demuxer->num_titles == 0)
-        stream_control(mpctx->demuxer->stream, STREAM_CTRL_GET_NUM_TITLES, &mpctx->demuxer->num_titles);
-    return m_property_int_ro(prop, action, arg, mpctx->demuxer->num_titles);
+    if (demuxer->num_titles == 0)
+        stream_control(demuxer->stream, STREAM_CTRL_GET_NUM_TITLES,
+                       &demuxer->num_titles);
+    return m_property_int_ro(prop, action, arg, demuxer->num_titles);
 }
 
 /// Number of chapters in file
 static int mp_property_chapters(m_option_t *prop, int action, void *arg,
                                 MPContext *mpctx)
 {
-    if (!mpctx->demuxer)
+    if (!mpctx->num_sources)
         return M_PROPERTY_UNAVAILABLE;
     int count = get_chapter_count(mpctx);
     return m_property_int_ro(prop, action, arg, count);
@@ -536,14 +542,15 @@ static int mp_property_angle(m_option_t *prop, int action, void *arg,
                              MPContext *mpctx)
 {
     struct MPOpts *opts = &mpctx->opts;
+    struct demuxer *demuxer = mpctx->master_demuxer;
     int angle = -1;
     int angles;
 
-    if (mpctx->demuxer)
-        angle = demuxer_get_current_angle(mpctx->demuxer);
+    if (demuxer)
+        angle = demuxer_get_current_angle(demuxer);
     if (angle < 0)
         return M_PROPERTY_UNAVAILABLE;
-    angles = demuxer_angles_count(mpctx->demuxer);
+    angles = demuxer_angles_count(demuxer);
     if (angles <= 1)
         return M_PROPERTY_UNAVAILABLE;
 
@@ -583,13 +590,13 @@ static int mp_property_angle(m_option_t *prop, int action, void *arg,
     default:
         return M_PROPERTY_NOT_IMPLEMENTED;
     }
-    angle = demuxer_set_angle(mpctx->demuxer, angle);
+    angle = demuxer_set_angle(demuxer, angle);
     if (angle >= 0) {
-        struct sh_video *sh_video = mpctx->demuxer->video->sh;
+        struct sh_video *sh_video = demuxer->video->sh;
         if (sh_video)
             resync_video_stream(sh_video);
 
-        struct sh_audio *sh_audio = mpctx->demuxer->audio->sh;
+        struct sh_audio *sh_audio = demuxer->audio->sh;
         if (sh_audio)
             resync_audio_stream(sh_audio);
     }
@@ -603,26 +610,28 @@ static int mp_property_angle(m_option_t *prop, int action, void *arg,
 static int mp_property_metadata(m_option_t *prop, int action, void *arg,
                                 MPContext *mpctx)
 {
+    struct demuxer *demuxer = mpctx->master_demuxer;
+    if (!demuxer)
+        return M_PROPERTY_UNAVAILABLE;
+
     m_property_action_t *ka;
     char *meta;
     static const m_option_t key_type =
     {
         "metadata", NULL, CONF_TYPE_STRING, 0, 0, 0, NULL
     };
-    if (!mpctx->demuxer)
-        return M_PROPERTY_UNAVAILABLE;
 
     switch (action) {
     case M_PROPERTY_GET:
         if (!arg)
             return M_PROPERTY_ERROR;
-        *(char ***)arg = mpctx->demuxer->info;
+        *(char ***)arg = demuxer->info;
         return M_PROPERTY_OK;
     case M_PROPERTY_KEY_ACTION:
         if (!arg)
             return M_PROPERTY_ERROR;
         ka = arg;
-        if (!(meta = demux_info_get(mpctx->demuxer, ka->key)))
+        if (!(meta = demux_info_get(demuxer, ka->key)))
             return M_PROPERTY_UNKNOWN;
         switch (ka->action) {
         case M_PROPERTY_GET:
@@ -889,7 +898,7 @@ static int mp_property_audio(m_option_t *prop, int action, void *arg,
                              MPContext *mpctx)
 {
     int current_id, tmp;
-    if (!mpctx->demuxer || !mpctx->d_audio)
+    if (!mpctx->num_sources)
         return M_PROPERTY_UNAVAILABLE;
     struct sh_audio *sh = mpctx->sh_audio;
     current_id = sh ? sh->aid : -2;
@@ -907,7 +916,7 @@ static int mp_property_audio(m_option_t *prop, int action, void *arg,
         if (!sh || current_id < 0)
             *(char **) arg = talloc_strdup(NULL, mp_gtext("disabled"));
         else {
-            char *lang = demuxer_stream_lang(mpctx->demuxer, sh->gsh);
+            char *lang = demuxer_stream_lang(sh->ds->demuxer, sh->gsh);
             if (!lang)
                 lang = talloc_strdup(NULL, mp_gtext("unknown"));
 
@@ -953,7 +962,7 @@ static int mp_property_video(m_option_t *prop, int action, void *arg,
 {
     struct MPOpts *opts = &mpctx->opts;
     int current_id, tmp;
-    if (!mpctx->demuxer || !mpctx->d_video)
+    if (!mpctx->num_sources)
         return M_PROPERTY_UNAVAILABLE;
     current_id = mpctx->sh_video ? mpctx->sh_video->vid : -2;
 
@@ -1005,7 +1014,8 @@ static int mp_property_program(m_option_t *prop, int action, void *arg,
 {
     demux_program_t prog;
 
-    if (!mpctx->demuxer)
+    struct demuxer *demuxer = mpctx->master_demuxer;
+    if (!demuxer)
         return M_PROPERTY_UNAVAILABLE;
 
     switch (action) {
@@ -1015,8 +1025,8 @@ static int mp_property_program(m_option_t *prop, int action, void *arg,
             prog.progid = *((int *) arg);
         else
             prog.progid = -1;
-        if (demux_control(mpctx->demuxer, DEMUXER_CTRL_IDENTIFY_PROGRAM,
-                          &prog) == DEMUXER_CTRL_NOTIMPL)
+        if (demux_control(demuxer, DEMUXER_CTRL_IDENTIFY_PROGRAM, &prog) ==
+            DEMUXER_CTRL_NOTIMPL)
             return M_PROPERTY_ERROR;
 
         if (prog.aid < 0 && prog.vid < 0) {
@@ -1354,7 +1364,7 @@ static int mp_property_gamma(m_option_t *prop, int action, void *arg,
     }
 
 #ifdef CONFIG_TV
-    if (mpctx->demuxer->type == DEMUXER_TYPE_TV) {
+    if (mpctx->sh_video->ds->demuxer->type == DEMUXER_TYPE_TV) {
         int l = strlen(prop->name);
         char tv_prop[3 + l + 1];
         sprintf(tv_prop, "tv_%s", prop->name);
@@ -1534,7 +1544,7 @@ static int mp_property_sub(m_option_t *prop, int action, void *arg,
         }
         if (opts->sub_id >= 0 && mpctx->d_sub && mpctx->d_sub->sh) {
             struct sh_stream *sh = ((struct sh_sub *)mpctx->d_sub->sh)->gsh;
-            char *lang = demuxer_stream_lang(mpctx->demuxer, sh);
+            char *lang = demuxer_stream_lang(sh->common_header->ds->demuxer, sh);
             if (!lang)
                 lang = talloc_strdup(NULL, mp_gtext("unknown"));
             if (sh->title)
@@ -2005,15 +2015,20 @@ static int mp_property_sub_scale(m_option_t *prop, int action, void *arg,
 
 #ifdef CONFIG_TV
 
+static tvi_handle_t *get_tvh(struct MPContext *mpctx)
+{
+    if (!(mpctx->master_demuxer && mpctx->master_demuxer->type == DEMUXER_TYPE_TV))
+        return NULL;
+    return mpctx->master_demuxer->priv;
+}
+
 /// TV color settings (RW)
 static int mp_property_tv_color(m_option_t *prop, int action, void *arg,
                                 MPContext *mpctx)
 {
     int r, val;
-    if (!mpctx->demuxer)
-        return M_PROPERTY_UNAVAILABLE;
-    tvi_handle_t *tvh = mpctx->demuxer->priv;
-    if (mpctx->demuxer->type != DEMUXER_TYPE_TV || !tvh)
+    tvi_handle_t *tvh = get_tvh(mpctx);
+    if (!tvh)
         return M_PROPERTY_UNAVAILABLE;
 
     switch (action) {
@@ -2499,7 +2514,7 @@ static char *format_time(double time)
 static void show_chapters_on_osd(MPContext *mpctx)
 {
     int count = get_chapter_count(mpctx);
-    int cur = mpctx->demuxer ? get_current_chapter(mpctx) : -1;
+    int cur = mpctx->num_sources ? get_current_chapter(mpctx) : -1;
     char *res = NULL;
     int n;
 
@@ -2527,7 +2542,7 @@ static void show_chapters_on_osd(MPContext *mpctx)
 static void show_tracks_on_osd(MPContext *mpctx)
 {
     struct MPOpts *opts = &mpctx->opts;
-    demuxer_t *demuxer = mpctx->demuxer;
+    demuxer_t *demuxer = mpctx->master_demuxer;
     char *res = NULL;
 
     if (!demuxer)
@@ -2557,7 +2572,7 @@ static void show_tracks_on_osd(MPContext *mpctx)
         res = talloc_asprintf_append(res, "(%d) ", sh->tid);
         if (sh->title)
             res = talloc_asprintf_append(res, "'%s' ", sh->title);
-        char *lang = demuxer_stream_lang(mpctx->demuxer, sh);
+        char *lang = demuxer_stream_lang(sh->common_header->ds->demuxer, sh);
         if (lang)
             res = talloc_asprintf_append(res, "(%s) ", lang);
         talloc_free(lang);
@@ -2888,53 +2903,50 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
 
 #ifdef CONFIG_RADIO
     case MP_CMD_RADIO_STEP_CHANNEL:
-        if (mpctx->demuxer && mpctx->demuxer->stream->type == STREAMTYPE_RADIO) {
+        if (mpctx->stream && mpctx->stream->type == STREAMTYPE_RADIO) {
             int v = cmd->args[0].v.i;
             if (v > 0)
-                radio_step_channel(mpctx->demuxer->stream,
-                                   RADIO_CHANNEL_HIGHER);
+                radio_step_channel(mpctx->stream, RADIO_CHANNEL_HIGHER);
             else
-                radio_step_channel(mpctx->demuxer->stream,
-                                   RADIO_CHANNEL_LOWER);
-            if (radio_get_channel_name(mpctx->demuxer->stream)) {
+                radio_step_channel(mpctx->stream, RADIO_CHANNEL_LOWER);
+            if (radio_get_channel_name(mpctx->stream)) {
                 set_osd_tmsg(OSD_MSG_RADIO_CHANNEL, 1, osd_duration,
                              "Channel: %s",
-                             radio_get_channel_name(mpctx->demuxer->stream));
+                             radio_get_channel_name(mpctx->stream));
             }
         }
         break;
 
     case MP_CMD_RADIO_SET_CHANNEL:
-        if (mpctx->demuxer && mpctx->demuxer->stream->type == STREAMTYPE_RADIO) {
-            radio_set_channel(mpctx->demuxer->stream, cmd->args[0].v.s);
-            if (radio_get_channel_name(mpctx->demuxer->stream)) {
+        if (mpctx->stream && mpctx->stream->type == STREAMTYPE_RADIO) {
+            radio_set_channel(mpctx->stream, cmd->args[0].v.s);
+            if (radio_get_channel_name(mpctx->stream)) {
                 set_osd_tmsg(OSD_MSG_RADIO_CHANNEL, 1, osd_duration,
                              "Channel: %s",
-                             radio_get_channel_name(mpctx->demuxer->stream));
+                             radio_get_channel_name(mpctx->stream));
             }
         }
         break;
 
     case MP_CMD_RADIO_SET_FREQ:
-        if (mpctx->demuxer && mpctx->demuxer->stream->type == STREAMTYPE_RADIO)
-            radio_set_freq(mpctx->demuxer->stream, cmd->args[0].v.f);
+        if (mpctx->stream && mpctx->stream->type == STREAMTYPE_RADIO)
+            radio_set_freq(mpctx->stream, cmd->args[0].v.f);
         break;
 
     case MP_CMD_RADIO_STEP_FREQ:
-        if (mpctx->demuxer && mpctx->demuxer->stream->type == STREAMTYPE_RADIO)
-            radio_step_freq(mpctx->demuxer->stream, cmd->args[0].v.f);
+        if (mpctx->stream && mpctx->stream->type == STREAMTYPE_RADIO)
+            radio_step_freq(mpctx->stream, cmd->args[0].v.f);
         break;
 #endif
 
 #ifdef CONFIG_TV
     case MP_CMD_TV_START_SCAN:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_start_scan((tvi_handle_t *) (mpctx->demuxer->priv), 1);
+        if (get_tvh(mpctx))
+            tv_start_scan(get_tvh(mpctx), 1);
         break;
     case MP_CMD_TV_SET_FREQ:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_set_freq((tvi_handle_t *) (mpctx->demuxer->priv),
-                        cmd->args[0].v.f * 16.0);
+        if (get_tvh(mpctx))
+            tv_set_freq(get_tvh(mpctx), cmd->args[0].v.f * 16.0);
 #ifdef CONFIG_PVR
         else if (mpctx->stream && mpctx->stream->type == STREAMTYPE_PVR) {
             pvr_set_freq(mpctx->stream, ROUND(cmd->args[0].v.f));
@@ -2946,9 +2958,8 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
         break;
 
     case MP_CMD_TV_STEP_FREQ:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_step_freq((tvi_handle_t *) (mpctx->demuxer->priv),
-                         cmd->args[0].v.f * 16.0);
+        if (get_tvh(mpctx))
+            tv_step_freq(get_tvh(mpctx), cmd->args[0].v.f * 16.0);
 #ifdef CONFIG_PVR
         else if (mpctx->stream && mpctx->stream->type == STREAMTYPE_PVR) {
             pvr_force_freq_step(mpctx->stream, ROUND(cmd->args[0].v.f));
@@ -2960,22 +2971,17 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
         break;
 
     case MP_CMD_TV_SET_NORM:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_set_norm((tvi_handle_t *) (mpctx->demuxer->priv),
-                        cmd->args[0].v.s);
+        if (get_tvh(mpctx))
+            tv_set_norm(get_tvh(mpctx), cmd->args[0].v.s);
         break;
 
     case MP_CMD_TV_STEP_CHANNEL:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV) {
+        if (get_tvh(mpctx)) {
             int v = cmd->args[0].v.i;
             if (v > 0) {
-                tv_step_channel((tvi_handle_t *) (mpctx->
-                                                  demuxer->priv),
-                                TV_CHANNEL_HIGHER);
+                tv_step_channel(get_tvh(mpctx), TV_CHANNEL_HIGHER);
             } else {
-                tv_step_channel((tvi_handle_t *) (mpctx->
-                                                  demuxer->priv),
-                                TV_CHANNEL_LOWER);
+                tv_step_channel(get_tvh(mpctx), TV_CHANNEL_LOWER);
             }
             if (tv_channel_list) {
                 set_osd_tmsg(mpctx, OSD_MSG_TV_CHANNEL, 1, osd_duration,
@@ -3013,9 +3019,8 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
         break;
 
     case MP_CMD_TV_SET_CHANNEL:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV) {
-            tv_set_channel((tvi_handle_t *) (mpctx->demuxer->priv),
-                           cmd->args[0].v.s);
+        if (get_tvh(mpctx)) {
+            tv_set_channel(get_tvh(mpctx), cmd->args[0].v.s);
             if (tv_channel_list) {
                 set_osd_tmsg(mpctx, OSD_MSG_TV_CHANNEL, 1, osd_duration,
                              "Channel: %s", tv_channel_current->name);
@@ -3047,8 +3052,8 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
 #endif /* CONFIG_DVBIN */
 
     case MP_CMD_TV_LAST_CHANNEL:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV) {
-            tv_last_channel((tvi_handle_t *) (mpctx->demuxer->priv));
+        if (get_tvh(mpctx)) {
+            tv_last_channel(get_tvh(mpctx));
             if (tv_channel_list) {
                 set_osd_tmsg(mpctx, OSD_MSG_TV_CHANNEL, 1, osd_duration,
                              "Channel: %s", tv_channel_current->name);
@@ -3066,13 +3071,13 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
         break;
 
     case MP_CMD_TV_STEP_NORM:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_step_norm((tvi_handle_t *) (mpctx->demuxer->priv));
+        if (get_tvh(mpctx))
+            tv_step_norm(get_tvh(mpctx));
         break;
 
     case MP_CMD_TV_STEP_CHANNEL_LIST:
-        if (mpctx->demuxer && mpctx->file_format == DEMUXER_TYPE_TV)
-            tv_step_chanlist((tvi_handle_t *) (mpctx->demuxer->priv));
+        if (get_tvh(mpctx))
+            tv_step_chanlist(get_tvh(mpctx));
         break;
 #endif /* CONFIG_TV */