avio: Collect and print statistics of bytes read & seeks

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/avio.h

@@ -128,6 +128,18 @@ typedef struct {
       * call the underlying seek function directly.
       */
      int direct;
+
+    /**
+     * Bytes read statistic
+     * This field is internal to libavformat and access from outside is not allowed.
+     */
+     int64_t bytes_read;
+
+    /**
+     * seek statistic
+     * This field is internal to libavformat and access from outside is not allowed.
+     */
+     int seek_count;
 } AVIOContext;
 
 /* unbuffered I/O */

libavformat/aviobuf.c

@@ -237,6 +237,7 @@ int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
             return AVERROR(EPIPE);
         if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
             return res;
+        s->seek_count ++;
         if (!s->write_flag)
             s->buf_end = s->buffer;
         s->buf_ptr = s->buffer;
@@ -423,6 +424,7 @@ static void fill_buffer(AVIOContext *s)
         s->pos += len;
         s->buf_ptr = dst;
         s->buf_end = dst + len;
+        s->bytes_read += len;
     }
 }
 
@@ -792,6 +794,8 @@ int avio_close(AVIOContext *s)
 
     h = s->opaque;
     av_free(s->buffer);
+    if (!s->write_flag)
+        av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
     av_free(s);
     return ffurl_close(h);
 }