stream: provide a common implementation of stream_Tell()

include/vlc_stream.h

@@ -142,6 +142,13 @@ VLC_API ssize_t stream_Read(stream_t *, void *, size_t) VLC_USED;
  */
 VLC_API ssize_t stream_Peek(stream_t *, const uint8_t **, size_t) VLC_USED;
 
+/**
+ * Tells the current stream position.
+ *
+ * @return the byte offset from the beginning of the stream (cannot fail)
+ */
+VLC_API uint64_t stream_Tell(const stream_t *) VLC_USED;
+
 VLC_API int stream_vaControl( stream_t *s, int i_query, va_list args );
 VLC_API void stream_Delete( stream_t *s );
 VLC_API int stream_Control( stream_t *s, int i_query, ... );
@@ -149,18 +156,6 @@ VLC_API block_t * stream_Block( stream_t *s, size_t );
 VLC_API char * stream_ReadLine( stream_t * );
 VLC_API input_item_t *stream_ReadDir( stream_t * );
 
-/**
- * Get the current position in a stream
- */
-static inline int64_t stream_Tell( stream_t *s )
-{
-    uint64_t i_pos;
-    stream_Control( s, STREAM_GET_POSITION, &i_pos );
-    if( i_pos >> 62 )
-        return (int64_t)1 << 62;
-    return i_pos;
-}
-
 /**
  * Get the size of the stream.
  */

src/input/stream.c

@@ -45,6 +45,7 @@ typedef struct stream_priv_t
 {
     stream_t stream;
     block_t *peek;
+    uint64_t offset;
 
     /* UTF-16 and UTF-32 file reading */
     struct {
@@ -75,6 +76,7 @@ stream_t *stream_CommonNew(vlc_object_t *parent)
     s->pf_destroy = NULL;
     s->p_input = NULL;
     priv->peek = NULL;
+    priv->offset = 0;
 
     /* UTF16 and UTF32 text file conversion */
     priv->text.conv = (vlc_iconv_t)(-1);
@@ -313,6 +315,7 @@ error:
 
 static ssize_t stream_ReadRaw(stream_t *s, void *buf, size_t len)
 {
+    stream_priv_t *priv = (stream_priv_t *)s;
     size_t copy = 0;
     ssize_t ret = 0;
 
@@ -333,6 +336,7 @@ static ssize_t stream_ReadRaw(stream_t *s, void *buf, size_t len)
             buf = (unsigned char *)buf + ret;
         len -= ret;
         copy += ret;
+        priv->offset += ret;
     }
 
     return (copy > 0) ? (ssize_t)copy : ret;
@@ -430,6 +434,20 @@ ssize_t stream_Peek(stream_t *s, const uint8_t **restrict bufp, size_t len)
     return len;
 }
 
+uint64_t stream_Tell(const stream_t *s)
+{
+    const stream_priv_t *priv = (const stream_priv_t *)s;
+    uint64_t pos = priv->offset;
+
+    if (priv->peek != NULL)
+    {
+        assert(pos >= priv->peek->i_buffer);
+        pos -= priv->peek->i_buffer;
+    }
+
+    return pos;
+}
+
 static int stream_ControlInternal(stream_t *s, int cmd, ...)
 {
     va_list ap;

src/libvlccore.sym

@@ -403,6 +403,7 @@ stream_MemoryNew
 stream_Peek
 stream_Read
 stream_ReadLine
+stream_Tell
 stream_UrlNew
 stream_vaControl
 stream_ReadDir