lavf: make cmdutils's check_stream_specifier public.

The new function is called avformat_match_stream_specifier()
and does not include logging the error message.

3 files changed, 79 insertions, 2 deletions

diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 3bbc68387d..1837733097 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1972,6 +1972,22 @@ const struct AVCodecTag *avformat_get_riff_audio_tags(void);
 AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame);
 
 /**
+ * Check if the stream st contained in s is matched by the stream specifier
+ * spec.
+ *
+ * See the "stream specifiers" chapter in the documentation for the syntax
+ * of spec.
+ *
+ * @return  >0 if st is matched by spec;
+ *          0  if st is not matched by spec;
+ *          AVERROR code if spec is invalid
+ *
+ * @note  A stream specifier can match several streams in the format.
+ */
+int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
+                                    const char *spec);
+
+/**
  * @}
  */
 
diff --git a/libavformat/utils.c b/libavformat/utils.c
index cfa9e82f3f..c437866d68 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -4509,3 +4509,64 @@ AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *strea
     else
         return frame_sample_aspect_ratio;
 }
+
+int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
+                                    const char *spec)
+{
+    if (*spec <= '9' && *spec >= '0') /* opt:index */
+        return strtol(spec, NULL, 0) == st->index;
+    else if (*spec == 'v' || *spec == 'a' || *spec == 's' || *spec == 'd' ||
+             *spec == 't') { /* opt:[vasdt] */
+        enum AVMediaType type;
+
+        switch (*spec++) {
+        case 'v': type = AVMEDIA_TYPE_VIDEO;      break;
+        case 'a': type = AVMEDIA_TYPE_AUDIO;      break;
+        case 's': type = AVMEDIA_TYPE_SUBTITLE;   break;
+        case 'd': type = AVMEDIA_TYPE_DATA;       break;
+        case 't': type = AVMEDIA_TYPE_ATTACHMENT; break;
+        default:  av_assert0(0);
+        }
+        if (type != st->codec->codec_type)
+            return 0;
+        if (*spec++ == ':') { /* possibly followed by :index */
+            int i, index = strtol(spec, NULL, 0);
+            for (i = 0; i < s->nb_streams; i++)
+                if (s->streams[i]->codec->codec_type == type && index-- == 0)
+                   return i == st->index;
+            return 0;
+        }
+        return 1;
+    } else if (*spec == 'p' && *(spec + 1) == ':') {
+        int prog_id, i, j;
+        char *endptr;
+        spec += 2;
+        prog_id = strtol(spec, &endptr, 0);
+        for (i = 0; i < s->nb_programs; i++) {
+            if (s->programs[i]->id != prog_id)
+                continue;
+
+            if (*endptr++ == ':') {
+                int stream_idx = strtol(endptr, NULL, 0);
+                return stream_idx >= 0 &&
+                    stream_idx < s->programs[i]->nb_stream_indexes &&
+                    st->index == s->programs[i]->stream_index[stream_idx];
+            }
+
+            for (j = 0; j < s->programs[i]->nb_stream_indexes; j++)
+                if (st->index == s->programs[i]->stream_index[j])
+                    return 1;
+        }
+        return 0;
+    } else if (*spec == '#') {
+        int sid;
+        char *endptr;
+        sid = strtol(spec + 1, &endptr, 0);
+        if (!*endptr)
+            return st->id == sid;
+    } else if (!*spec) /* empty specifier, matches everything */
+        return 1;
+
+    av_log(s, AV_LOG_ERROR, "Invalid stream specifier: %s.\n", spec);
+    return AVERROR(EINVAL);
+}
diff --git a/libavformat/version.h b/libavformat/version.h
index 234c7a4bdf..0b977a401d 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -30,8 +30,8 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
-#define LIBAVFORMAT_VERSION_MINOR 17
-#define LIBAVFORMAT_VERSION_MICRO 101
+#define LIBAVFORMAT_VERSION_MINOR 18
+#define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \