revise webpload for improved loader pattern

libvips/foreign/webpload.c

@@ -58,6 +58,10 @@
 typedef struct _VipsForeignLoadWebp {
 	VipsForeignLoad parent_object;
 
+	/* Set by subclasses.
+	 */
+	VipsStreami *streami;
+
 	/* Load this page (frame number).
 	 */
 	int page;
@@ -80,17 +84,67 @@ typedef VipsForeignLoadClass VipsForeignLoadWebpClass;
 G_DEFINE_ABSTRACT_TYPE( VipsForeignLoadWebp, vips_foreign_load_webp, 
 	VIPS_TYPE_FOREIGN_LOAD );
 
+static void
+vips_foreign_load_webp_dispose( GObject *gobject )
+{
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) gobject;
+
+	VIPS_UNREF( webp->streami );
+
+	G_OBJECT_CLASS( vips_foreign_load_webp_parent_class )->
+		dispose( gobject );
+}
+
+static int
+vips_foreign_load_webp_build( VipsObject *object )
+{
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) object;
+
+	/* BC for the old API.
+	 */
+	if( !vips_object_argument_isset( VIPS_OBJECT( webp ), "scale" ) &&
+		vips_object_argument_isset( VIPS_OBJECT( webp ), "shrink" ) &&
+		webp->shrink != 0 )
+		webp->scale = 1.0 / webp->shrink;
+
+	if( VIPS_OBJECT_CLASS( vips_foreign_load_webp_parent_class )->
+		build( object ) )
+		return( -1 );
+
+	return( 0 );
+}
+
 static VipsForeignFlags
 vips_foreign_load_webp_get_flags( VipsForeignLoad *load )
 {
 	return( 0 );
 }
 
-static int
+static VipsForeignFlags
-vips_foreign_load_webp_build( VipsObject *object )
+vips_foreign_load_webp_get_flags_filename( const char *filename )
 {
-	if( VIPS_OBJECT_CLASS( vips_foreign_load_webp_parent_class )->
+	return( 0 );
-		build( object ) )
+}
+
+static int
+vips_foreign_load_webp_header( VipsForeignLoad *load )
+{
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
+
+	if( vips__webp_read_header_stream( webp->streami, load->out, 
+		webp->page, webp->n, webp->scale ) ) 
+		return( -1 );
+
+	return( 0 );
+}
+
+static int
+vips_foreign_load_webp_load( VipsForeignLoad *load )
+{
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
+
+	if( vips__webp_read_stream( webp->streami, load->real, 
+		webp->page, webp->n, webp->scale ) ) 
 		return( -1 );
 
 	return( 0 );
@@ -101,8 +155,10 @@ vips_foreign_load_webp_class_init( VipsForeignLoadWebpClass *class )
 {
 	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
 	VipsObjectClass *object_class = (VipsObjectClass *) class;
+	VipsForeignClass *foreign_class = (VipsForeignClass *) class;
 	VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
 
+	gobject_class->dispose = vips_foreign_load_webp_dispose;
 	gobject_class->set_property = vips_object_set_property;
 	gobject_class->get_property = vips_object_get_property;
 
@@ -110,7 +166,15 @@ vips_foreign_load_webp_class_init( VipsForeignLoadWebpClass *class )
 	object_class->description = _( "load webp" );
 	object_class->build = vips_foreign_load_webp_build;
 
+	/* is_a() is not that quick ... lower the priority.
+	 */
+	foreign_class->priority = -50;
+
+	load_class->get_flags_filename = 
+		vips_foreign_load_webp_get_flags_filename;
 	load_class->get_flags = vips_foreign_load_webp_get_flags;
+	load_class->header = vips_foreign_load_webp_header;
+	load_class->load = vips_foreign_load_webp_load;
 
 	VIPS_ARG_INT( class, "page", 20,
 		_( "Page" ),
@@ -166,26 +230,19 @@ G_DEFINE_TYPE( VipsForeignLoadWebpStream, vips_foreign_load_webp_stream,
 	vips_foreign_load_webp_get_type() );
 
 static int
-vips_foreign_load_webp_stream_header( VipsForeignLoad *load )
+vips_foreign_load_webp_stream_build( VipsObject *object )
 {
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) object;
-	VipsForeignLoadWebpStream *stream = (VipsForeignLoadWebpStream *) load;
+	VipsForeignLoadWebpStream *stream = 
+		(VipsForeignLoadWebpStream *) object;
 
-	if( vips__webp_read_header_stream( stream->streami, load->out, 
+	if( stream->streami ) {
-		webp->page, webp->n, webp->scale ) ) 
+		webp->streami = stream->streami;
-		return( -1 );
+		g_object_ref( webp->streami );
+	}
 
-	return( 0 );
+	if( VIPS_OBJECT_CLASS( vips_foreign_load_webp_stream_parent_class )->
-}
+		build( object ) )
-
-static int
-vips_foreign_load_webp_stream_load( VipsForeignLoad *load )
-{
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
-	VipsForeignLoadWebpStream *stream = (VipsForeignLoadWebpStream *) load;
-
-	if( vips__webp_read_stream( stream->streami, load->real, 
-		webp->page, webp->n, webp->scale ) ) 
 		return( -1 );
 
 	return( 0 );
@@ -197,7 +254,6 @@ vips_foreign_load_webp_stream_class_init(
 {
 	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
 	VipsObjectClass *object_class = (VipsObjectClass *) class;
-	VipsForeignClass *foreign_class = (VipsForeignClass *) class;
 	VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
 
 	gobject_class->set_property = vips_object_set_property;
@@ -205,14 +261,9 @@ vips_foreign_load_webp_stream_class_init(
 
 	object_class->nickname = "webpload_stream";
 	object_class->description = _( "load webp from stream" );
-
+	object_class->build = vips_foreign_load_webp_stream_build;
-	/* is_a() is not that quick ... lower the priority.
-	 */
-	foreign_class->priority = -50;
 
 	load_class->is_a_stream = vips__iswebp_stream; 
-	load_class->header = vips_foreign_load_webp_stream_header;
-	load_class->load = vips_foreign_load_webp_stream_load;
 
 	VIPS_ARG_OBJECT( class, "streami", 1,
 		_( "Streami" ),
@@ -242,9 +293,21 @@ typedef VipsForeignLoadWebpClass VipsForeignLoadWebpFileClass;
 G_DEFINE_TYPE( VipsForeignLoadWebpFile, vips_foreign_load_webp_file, 
 	vips_foreign_load_webp_get_type() );
 
-static VipsForeignFlags
+static int
-vips_foreign_load_webp_file_get_flags_filename( const char *filename )
+vips_foreign_load_webp_file_build( VipsObject *object )
 {
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) object;
+	VipsForeignLoadWebpFile *file = (VipsForeignLoadWebpFile *) object;
+
+	if( file->filename &&
+		!(webp->streami = 
+			vips_streami_new_from_file( file->filename )) )
+		return( -1 );
+
+	if( VIPS_OBJECT_CLASS( vips_foreign_load_webp_file_parent_class )->
+		build( object ) )
+		return( -1 );
+
 	return( 0 );
 }
 
@@ -262,53 +325,6 @@ vips_foreign_load_webp_file_is_a( const char *filename )
 	return( result );
 }
 
-static int
-vips_foreign_load_webp_file_header( VipsForeignLoad *load )
-{
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
-	VipsForeignLoadWebpFile *file = (VipsForeignLoadWebpFile *) load;
-
-	VipsStreami *streami;
-
-	/* BC for the old API.
-	 */
-	if( !vips_object_argument_isset( VIPS_OBJECT( load ), "scale" ) &&
-		vips_object_argument_isset( VIPS_OBJECT( load ), "shrink" ) &&
-		webp->shrink != 0 )
-		webp->scale = 1.0 / webp->shrink;
-
-	if( !(streami = vips_streami_new_from_file( file->filename )) )
-		return( -1 );
-	if( vips__webp_read_header_stream( streami, load->out, 
-		webp->page, webp->n, webp->scale ) ) {
-		VIPS_UNREF( streami );
-		return( -1 );
-	}
-	VIPS_UNREF( streami );
-
-	return( 0 );
-}
-
-static int
-vips_foreign_load_webp_file_load( VipsForeignLoad *load )
-{
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
-	VipsForeignLoadWebpFile *file = (VipsForeignLoadWebpFile *) load;
-
-	VipsStreami *streami;
-
-	if( !(streami = vips_streami_new_from_file( file->filename )) )
-		return( -1 );
-	if( vips__webp_read_stream( streami, load->real, 
-		webp->page, webp->n, webp->scale ) ) {
-		VIPS_UNREF( streami );
-		return( -1 );
-	}
-	VIPS_UNREF( streami );
-
-	return( 0 );
-}
-
 const char *vips__webp_suffs[] = { ".webp", NULL };
 
 static void
@@ -324,14 +340,11 @@ vips_foreign_load_webp_file_class_init( VipsForeignLoadWebpFileClass *class )
 
 	object_class->nickname = "webpload";
 	object_class->description = _( "load webp from file" );
+	object_class->build = vips_foreign_load_webp_file_build;
 
 	foreign_class->suffs = vips__webp_suffs;
 
-	load_class->get_flags_filename = 
-		vips_foreign_load_webp_file_get_flags_filename;
 	load_class->is_a = vips_foreign_load_webp_file_is_a;
-	load_class->header = vips_foreign_load_webp_file_header;
-	load_class->load = vips_foreign_load_webp_file_load;
 
 	VIPS_ARG_STRING( class, "filename", 1, 
 		_( "Filename" ),
@@ -351,7 +364,7 @@ typedef struct _VipsForeignLoadWebpBuffer {
 
 	/* Load from a buffer.
 	 */
-	VipsArea *buf;
+	VipsBlob *blob;
 
 } VipsForeignLoadWebpBuffer;
 
@@ -360,6 +373,26 @@ typedef VipsForeignLoadWebpClass VipsForeignLoadWebpBufferClass;
 G_DEFINE_TYPE( VipsForeignLoadWebpBuffer, vips_foreign_load_webp_buffer, 
 	vips_foreign_load_webp_get_type() );
 
+static int
+vips_foreign_load_webp_buffer_build( VipsObject *object )
+{
+	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) object;
+	VipsForeignLoadWebpBuffer *buffer = 
+		(VipsForeignLoadWebpBuffer *) object;
+
+	if( buffer->blob &&
+		!(webp->streami = vips_streami_new_from_memory( 
+			VIPS_AREA( buffer->blob )->data, 
+			VIPS_AREA( buffer->blob )->length )) )
+		return( -1 );
+
+	if( VIPS_OBJECT_CLASS( vips_foreign_load_webp_buffer_parent_class )->
+		build( object ) )
+		return( -1 );
+
+	return( 0 );
+}
+
 static gboolean
 vips_foreign_load_webp_buffer_is_a_buffer( const void *buf, size_t len )
 {
@@ -374,55 +407,12 @@ vips_foreign_load_webp_buffer_is_a_buffer( const void *buf, size_t len )
 	return( result );
 }
 
-static int
-vips_foreign_load_webp_buffer_header( VipsForeignLoad *load )
-{
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
-	VipsForeignLoadWebpBuffer *buffer = (VipsForeignLoadWebpBuffer *) load;
-
-	VipsStreami *streami;
-
-	if( !(streami = vips_streami_new_from_memory( buffer->buf->data,
-                buffer->buf->length )) )
-		return( FALSE );
-	if( vips__webp_read_header_stream( streami, load->out, 
-		webp->page, webp->n, webp->scale ) ) {
-		VIPS_UNREF( streami );
-		return( -1 );
-	}
-	VIPS_UNREF( streami );
-
-	return( 0 );
-}
-
-static int
-vips_foreign_load_webp_buffer_load( VipsForeignLoad *load )
-{
-	VipsForeignLoadWebp *webp = (VipsForeignLoadWebp *) load;
-	VipsForeignLoadWebpBuffer *buffer = (VipsForeignLoadWebpBuffer *) load;
-
-	VipsStreami *streami;
-
-	if( !(streami = vips_streami_new_from_memory( buffer->buf->data,
-                buffer->buf->length )) )
-		return( FALSE );
-	if( vips__webp_read_stream( streami, load->real, 
-		webp->page, webp->n, webp->scale ) ) {
-		VIPS_UNREF( streami );
-		return( -1 );
-	}
-	VIPS_UNREF( streami );
-
-	return( 0 );
-}
-
 static void
 vips_foreign_load_webp_buffer_class_init( 
 	VipsForeignLoadWebpBufferClass *class )
 {
 	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
 	VipsObjectClass *object_class = (VipsObjectClass *) class;
-	VipsForeignClass *foreign_class = (VipsForeignClass *) class;
 	VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
 
 	gobject_class->set_property = vips_object_set_property;
@@ -430,20 +420,15 @@ vips_foreign_load_webp_buffer_class_init(
 
 	object_class->nickname = "webpload_buffer";
 	object_class->description = _( "load webp from buffer" );
-
+	object_class->build = vips_foreign_load_webp_buffer_build;
-	/* is_a() is not that quick ... lower the priority.
-	 */
-	foreign_class->priority = -50;
 
 	load_class->is_a_buffer = vips_foreign_load_webp_buffer_is_a_buffer; 
-	load_class->header = vips_foreign_load_webp_buffer_header;
-	load_class->load = vips_foreign_load_webp_buffer_load;
 
 	VIPS_ARG_BOXED( class, "buffer", 1, 
 		_( "Buffer" ),
 		_( "Buffer to load from" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT, 
-		G_STRUCT_OFFSET( VipsForeignLoadWebpBuffer, buf ),
+		G_STRUCT_OFFSET( VipsForeignLoadWebpBuffer, blob ),
 		VIPS_TYPE_BLOB );
 }