fftools/ffmpeg: return errors from find_codec_or_die() instead of aborting

Rename the function to just find_codec().

fftools/ffmpeg.h

@@ -709,8 +709,8 @@ void assert_avoptions(AVDictionary *m);
 int assert_file_overwrite(const char *filename);
 char *file_read(const char *filename);
 AVDictionary *strip_specifiers(const AVDictionary *dict);
-const AVCodec *find_codec_or_die(void *logctx, const char *name,
-                                 enum AVMediaType type, int encoder);
+int find_codec(void *logctx, const char *name,
+               enum AVMediaType type, int encoder, const AVCodec **codec);
 int parse_and_set_vsync(const char *arg, int *vsync_var, int file_idx, int st_idx, int is_global);
 
 int check_filter_outputs(void);

fftools/ffmpeg_demux.c

@@ -911,19 +911,22 @@ int ist_filter_add(InputStream *ist, InputFilter *ifilter, int is_simple)
     return 0;
 }
 
-static const AVCodec *choose_decoder(const OptionsContext *o, AVFormatContext *s, AVStream *st,
-                                     enum HWAccelID hwaccel_id, enum AVHWDeviceType hwaccel_device_type)
+static int choose_decoder(const OptionsContext *o, AVFormatContext *s, AVStream *st,
+                          enum HWAccelID hwaccel_id, enum AVHWDeviceType hwaccel_device_type,
+                          const AVCodec **pcodec)
 
 {
     char *codec_name = NULL;
 
     MATCH_PER_STREAM_OPT(codec_names, str, codec_name, s, st);
     if (codec_name) {
-        const AVCodec *codec = find_codec_or_die(NULL, codec_name, st->codecpar->codec_type, 0);
-        st->codecpar->codec_id = codec->id;
-        if (recast_media && st->codecpar->codec_type != codec->type)
-            st->codecpar->codec_type = codec->type;
-        return codec;
+        int ret = find_codec(NULL, codec_name, st->codecpar->codec_type, 0, pcodec);
+        if (ret < 0)
+            return ret;
+        st->codecpar->codec_id = (*pcodec)->id;
+        if (recast_media && st->codecpar->codec_type != (*pcodec)->type)
+            st->codecpar->codec_type = (*pcodec)->type;
+        return 0;
     } else {
         if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
             hwaccel_id == HWACCEL_GENERIC &&
@@ -942,13 +945,15 @@ static const AVCodec *choose_decoder(const OptionsContext *o, AVFormatContext *s
                     if (config->device_type == hwaccel_device_type) {
                         av_log(NULL, AV_LOG_VERBOSE, "Selecting decoder '%s' because of requested hwaccel method %s\n",
                                c->name, av_hwdevice_get_type_name(hwaccel_device_type));
-                        return c;
+                        *pcodec = c;
+                        return 0;
                     }
                 }
             }
         }
 
-        return avcodec_find_decoder(st->codecpar->codec_id);
+        *pcodec = avcodec_find_decoder(st->codecpar->codec_id);
+        return 0;
     }
 }
 
@@ -1166,7 +1171,11 @@ static int ist_add(const OptionsContext *o, Demuxer *d, AVStream *st)
         }
     }
 
-    ist->dec = choose_decoder(o, ic, st, ist->hwaccel_id, ist->hwaccel_device_type);
+    ret = choose_decoder(o, ic, st, ist->hwaccel_id, ist->hwaccel_device_type,
+                         &ist->dec);
+    if (ret < 0)
+        return ret;
+
     ist->decoder_opts = filter_codec_opts(o->g->codec_opts, ist->st->codecpar->codec_id, ic, st, ist->dec);
 
     ist->reinit_filters = -1;
@@ -1357,7 +1366,7 @@ int ifile_open(const OptionsContext *o, const char *filename)
     InputFile *f;
     AVFormatContext *ic;
     const AVInputFormat *file_iformat = NULL;
-    int err, i, ret;
+    int err, i, ret = 0;
     int64_t timestamp;
     AVDictionary *unused_opts = NULL;
     const AVDictionaryEntry *e = NULL;
@@ -1455,13 +1464,19 @@ int ifile_open(const OptionsContext *o, const char *filename)
     MATCH_PER_TYPE_OPT(codec_names, str,     data_codec_name, ic, "d");
 
     if (video_codec_name)
-        ic->video_codec    = find_codec_or_die(NULL, video_codec_name   , AVMEDIA_TYPE_VIDEO   , 0);
+        ret = err_merge(ret, find_codec(NULL, video_codec_name   , AVMEDIA_TYPE_VIDEO   , 0,
+                                        &ic->video_codec));
     if (audio_codec_name)
-        ic->audio_codec    = find_codec_or_die(NULL, audio_codec_name   , AVMEDIA_TYPE_AUDIO   , 0);
+        ret = err_merge(ret, find_codec(NULL, audio_codec_name   , AVMEDIA_TYPE_AUDIO   , 0,
+                                        &ic->audio_codec));
     if (subtitle_codec_name)
-        ic->subtitle_codec = find_codec_or_die(NULL, subtitle_codec_name, AVMEDIA_TYPE_SUBTITLE, 0);
+        ret = err_merge(ret, find_codec(NULL, subtitle_codec_name, AVMEDIA_TYPE_SUBTITLE, 0,
+                                        &ic->subtitle_codec));
     if (data_codec_name)
-        ic->data_codec     = find_codec_or_die(NULL, data_codec_name    , AVMEDIA_TYPE_DATA    , 0);
+        ret = err_merge(ret, find_codec(NULL, data_codec_name    , AVMEDIA_TYPE_DATA,     0,
+                                        &ic->data_codec));
+    if (ret < 0)
+        return ret;
 
     ic->video_codec_id     = video_codec_name    ? ic->video_codec->id    : AV_CODEC_ID_NONE;
     ic->audio_codec_id     = audio_codec_name    ? ic->audio_codec->id    : AV_CODEC_ID_NONE;
@@ -1496,8 +1511,13 @@ int ifile_open(const OptionsContext *o, const char *filename)
     assert_avoptions(o->g->format_opts);
 
     /* apply forced codec ids */
-    for (i = 0; i < ic->nb_streams; i++)
-        choose_decoder(o, ic, ic->streams[i], HWACCEL_NONE, AV_HWDEVICE_TYPE_NONE);
+    for (i = 0; i < ic->nb_streams; i++) {
+        const AVCodec *dummy;
+        ret = choose_decoder(o, ic, ic->streams[i], HWACCEL_NONE, AV_HWDEVICE_TYPE_NONE,
+                             &dummy);
+        if (ret < 0)
+            return ret;
+    }
 
     if (o->find_stream_info) {
         AVDictionary **opts;

fftools/ffmpeg_mux_init.c

@@ -139,7 +139,9 @@ static int choose_encoder(const OptionsContext *o, AVFormatContext *s,
             return AVERROR_ENCODER_NOT_FOUND;
         }
     } else if (strcmp(codec_name, "copy")) {
-        *enc = find_codec_or_die(ost, codec_name, ost->type, 1);
+        int ret = find_codec(ost, codec_name, ost->type, 1, enc);
+        if (ret < 0)
+            return ret;
         ost->par_in->codec_id = (*enc)->id;
     }
 

fftools/ffmpeg_opt.c

@@ -637,8 +637,8 @@ static int opt_recording_timestamp(void *optctx, const char *opt, const char *ar
     return 0;
 }
 
-const AVCodec *find_codec_or_die(void *logctx, const char *name,
-                                 enum AVMediaType type, int encoder)
+int find_codec(void *logctx, const char *name,
+               enum AVMediaType type, int encoder, const AVCodec **pcodec)
 {
     const AVCodecDescriptor *desc;
     const char *codec_string = encoder ? "encoder" : "decoder";
@@ -658,13 +658,16 @@ const AVCodec *find_codec_or_die(void *logctx, const char *name,
 
     if (!codec) {
         av_log(logctx, AV_LOG_FATAL, "Unknown %s '%s'\n", codec_string, name);
-        exit_program(1);
+        return encoder ? AVERROR_ENCODER_NOT_FOUND :
+                         AVERROR_DECODER_NOT_FOUND;
     }
     if (codec->type != type && !recast_media) {
         av_log(logctx, AV_LOG_FATAL, "Invalid %s type '%s'\n", codec_string, name);
-        exit_program(1);
+        return AVERROR(EINVAL);
     }
-    return codec;
+
+    *pcodec = codec;
+    return 0;;
 }
 
 int assert_file_overwrite(const char *filename)