#include <vlc_common.h>
+#include <assert.h>
+
#include "input_internal.h"
#undef STREAM_DEBUG
/* TODO:
- * - tune the 2 methods
+ * - tune the 2 methods (block/stream)
* - compute cost for seek
* - improve stream mode seeking with closest segments
* - ...
+ * - Maybe remove (block/stream) in favour of immediate
*/
/* Two methods:
* One linked list of data read
* - using pf_read
* More complex scheme using mutliple track to avoid seeking
+ * - using directly the access (only indirection for peeking).
+ * This method is known to introduce much less latency.
+ * It should probably defaulted (instead of the stream method (2)).
*/
/* How many tracks we have, currently only used for stream mode */
} access_entry_t;
+typedef enum stream_read_method_t
+{
+ Immediate,
+ Block,
+ Stream
+} stream_read_method_t;
+
struct stream_sys_t
{
access_t *p_access;
- bool b_block; /* Block method (1) or stream */
+ stream_read_method_t method; /* method to use */
int64_t i_pos; /* Current reading offset */
} stream;
+ /* Method 3: for pf_read */
+ struct
+ {
+ int64_t i_end;
+ uint8_t *p_buffer;
+ } immediate;
+
/* Peek temporary buffer */
int i_peek;
uint8_t *p_peek;
static void AStreamPrebufferStream( stream_t *s );
static int AReadStream( stream_t *s, void *p_read, int i_read );
+/* Method 3 */
+static int AStreamReadImmediate( stream_t *s, void *p_read, int i_read );
+static int AStreamPeekImmediate( stream_t *s, const uint8_t **pp_peek, int i_read );
+static int AStreamSeekImmediate( stream_t *s, int64_t i_pos );
+
/* Common */
static int AStreamControl( stream_t *s, int i_query, va_list );
static void AStreamDestroy( stream_t *s );
static void UStreamDestroy( stream_t *s );
static int ASeek( stream_t *s, int64_t i_pos );
+/****************************************************************************
+ * Method 3 helpers:
+ ****************************************************************************/
+
+static inline int64_t stream_buffered_size( stream_t *s )
+{
+ return s->p_sys->immediate.i_end;
+}
+
+static inline void stream_buffer_empty( stream_t *s, int length )
+{
+ length = __MAX( stream_buffered_size( s ), length );
+ if( length )
+ {
+ memmove( s->p_sys->immediate.p_buffer,
+ s->p_sys->immediate.p_buffer + length,
+ stream_buffered_size( s ) - length );
+ }
+ s->p_sys->immediate.i_end -= length;
+}
+
+static inline void stream_buffer_fill( stream_t *s, int length )
+{
+ s->p_sys->immediate.i_end += length;
+}
+
+static inline uint8_t * stream_buffer( stream_t *s )
+{
+ return s->p_sys->immediate.p_buffer;
+}
/****************************************************************************
* stream_UrlNew: create a stream from a access
/* Common field */
p_sys->p_access = p_access;
- p_sys->b_block = p_access->pf_block ? true : false;
+ if( p_access->pf_block )
+ p_sys->method = Block;
+ else if (var_CreateGetBool( s, "use-stream-immediate"))
+ p_sys->method = Immediate;
+ else
+ p_sys->method = Stream;
+
p_sys->i_pos = p_access->info.i_pos;
/* Stats */
p_sys->i_peek = 0;
p_sys->p_peek = NULL;
- if( p_sys->b_block )
+ if( p_sys->method == Block )
{
+ msg_Dbg( s, "Using AStream*Block" );
s->pf_read = AStreamReadBlock;
s->pf_peek = AStreamPeekBlock;
goto error;
}
}
- else
+ else if (p_sys->method == Immediate)
+ {
+ msg_Dbg( s, "Using AStream*Immediate" );
+
+ s->pf_read = AStreamReadImmediate;
+ s->pf_peek = AStreamPeekImmediate;
+
+ /* Allocate/Setup our tracks (useful to peek)*/
+ p_sys->immediate.i_end = 0;
+ p_sys->immediate.p_buffer = malloc( STREAM_CACHE_SIZE );
+
+ msg_Dbg( s, "p_buffer %p-%p", p_sys->immediate.p_buffer,
+ p_sys->immediate.p_buffer + STREAM_CACHE_SIZE );
+
+ if( p_sys->immediate.p_buffer == NULL )
+ {
+ msg_Err( s, "Out of memory when allocating stream cache (%d bytes)",
+ STREAM_CACHE_SIZE );
+ goto error;
+ }
+ }
+ else /* ( p_sys->method == Stream ) */
{
int i;
+ msg_Dbg( s, "Using AStream*Stream" );
+
s->pf_read = AStreamReadStream;
s->pf_peek = AStreamPeekStream;
return s;
error:
- if( p_sys->b_block )
+ if( p_sys->method == Block )
{
/* Nothing yet */
}
vlc_object_detach( s );
- if( p_sys->b_block ) block_ChainRelease( p_sys->block.p_first );
+ if( p_sys->method == Block ) block_ChainRelease( p_sys->block.p_first );
else free( p_sys->stream.p_buffer );
free( p_sys->p_peek );
p_sys->i_pos = p_sys->p_access->info.i_pos;
- if( p_sys->b_block )
+ if( p_sys->method == Block )
{
block_ChainRelease( p_sys->block.p_first );
/* Do the prebuffering */
AStreamPrebufferBlock( s );
}
- else
+ else if( p_sys->method == Immediate )
+ {
+ stream_buffer_empty( s, stream_buffered_size( s ) );
+ }
+ else /* ( p_sys->method == Stream ) */
{
int i;
case STREAM_SET_POSITION:
i_64 = (int64_t)va_arg( args, int64_t );
- if( p_sys->b_block )
+ if( p_sys->method == Block )
return AStreamSeekBlock( s, i_64 );
- else
+ else if( p_sys->method == Immediate )
+ return AStreamSeekImmediate( s, i_64 );
+ else /* ( p_sys->method == Stream ) */
return AStreamSeekStream( s, i_64 );
case STREAM_GET_MTU:
}
}
+/****************************************************************************
+ * Method 3:
+ ****************************************************************************/
+
+static int AStreamReadImmediate( stream_t *s, void *p_read, int i_read )
+{
+ stream_sys_t *p_sys = s->p_sys;
+
+#ifdef STREAM_DEBUG
+ msg_Dbg( s, "AStreamReadImmediate p_read=%p i_read=%d",
+ p_read, i_read );
+#endif
+
+ if( p_read == NULL )
+ {
+ /* seek within this stream if possible, else use plain old read and discard */
+ stream_sys_t *p_sys = s->p_sys;
+ access_t *p_access = p_sys->p_access;
+ bool b_aseek;
+ access_Control( p_access, ACCESS_CAN_SEEK, &b_aseek );
+ if( b_aseek )
+ return AStreamSeekStream( s, p_sys->i_pos + i_read ) ? 0 : i_read;
+ }
+
+ /* First, check if we already have some data in the buffer,
+ * that we could copy directly */
+ int i_copy = __MIN( stream_buffered_size( s ), i_read );
+ if( i_copy )
+ {
+#ifdef STREAM_DEBUG
+ msg_Dbg( s, "AStreamReadImmediate: copy %d from %p", i_copy, stream_buffer( s ) );
+#endif
+
+ assert( i_copy <= STREAM_CACHE_SIZE );
+
+ if( p_read )
+ {
+ memcpy( p_read, stream_buffer( s ), i_copy );
+ p_read = (uint8_t *)p_read + i_copy;
+ }
+ }
+
+ /* Now that we've read our buffer we don't need its i_copy bytes */
+ stream_buffer_empty( s, i_copy );
+
+ /* Now check if we have still to really read some data */
+ int i_to_read = i_read - i_copy;
+ if( i_to_read )
+ {
+ i_to_read = AReadStream( s, p_read, i_to_read );
+ }
+
+ p_sys->i_pos += i_to_read;
+
+ return i_to_read + i_copy;
+}
+
+static int AStreamPeekImmediate( stream_t *s, const uint8_t **pp_peek, int i_read )
+{
+#ifdef STREAM_DEBUG
+ msg_Dbg( s, "AStreamPeekImmediate: %d size=%"PRId64,
+ i_read, size_buffered_size( s ) );
+#endif
+
+ /* Avoid problem, but that shouldn't happen */
+ if( i_read > STREAM_CACHE_SIZE / 2 )
+ i_read = STREAM_CACHE_SIZE / 2;
+
+ int i_to_read = i_read - stream_buffered_size( s );
+ if( i_to_read > 0 )
+ {
+#ifdef STREAM_DEBUG
+ msg_Dbg( s, "AStreamPeekImmediate: Reading %d",
+ i_to_read );
+#endif
+ i_to_read = AReadStream( s, stream_buffer( s ) + stream_buffered_size( s ),
+ i_to_read );
+
+ if( i_to_read > 0 )
+ stream_buffer_fill( s, i_to_read );
+ }
+
+ *pp_peek = stream_buffer( s );
+
+ return __MIN(stream_buffered_size( s ), i_read);
+}
+
+static int AStreamSeekImmediate( stream_t *s, int64_t i_pos )
+{
+ stream_sys_t *p_sys = s->p_sys;
+ access_t *p_access = p_sys->p_access;
+ bool b_aseek;
+
+#ifdef STREAM_DEBUG
+ msg_Dbg( s, "AStreamSeekImmediate to %"PRId64" pos=%"PRId64
+ i_pos, p_sys->i_pos );
+#endif
+
+ access_Control( p_access, ACCESS_CAN_SEEK, &b_aseek );
+ if( !b_aseek )
+ {
+ /* We can't do nothing */
+ msg_Dbg( s, "AStreamSeekImmediate: can't seek" );
+ return VLC_EGENERIC;
+ }
+
+ /* Just reset our buffer */
+ stream_buffer_empty( s, stream_buffered_size( s ) );
+
+ if( ASeek( s, i_pos ) ) return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+}
/****************************************************************************
* stream_ReadLine:
projects / vlc / blobdiff