Make it possible to call gdk_pixbuf_loader_set_size (loader, 0, 0) by

Wed Jan  7 01:17:36 2004  Matthias Clasen  <maclas@gmx.de>

	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_size_func):
	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_set_size):
	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_init): Make it possible
	to call gdk_pixbuf_loader_set_size (loader, 0, 0) by changing
	the initial values of priv->width/height to -1.

	* io-tiff.c (tiff_image_parse):
	* io-ras.c (RAS2State):
	* io-pnm.c (gdk_pixbuf__pnm_image_load_increment):
	* io-pcx.c (gdk_pixbuf__pcx_load_increment):
	* io-jpeg.c (gdk_pixbuf__jpeg_image_load_increment):
	* io-png.c (png_info_callback):
	* io-ico.c (DecodeHeader):
	* io-bmp.c (DecodeHeader): Call size_func once the size is known,
	even if the module can't make use of the scaling information. If
	size_func returns 0, don't allocate a pixbuf and return, if
	necessary with an error.

	* gdk-pixbuf.h:
	* gdk-pixbuf-io.c (gdk_pixbuf_get_file_info): A new function
	to determine the type and size of an image file without loading
	it completely.  (#53725)

13 files changed, 250 insertions, 29 deletions

diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index f11a942d3..796b17833 100644
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,28 @@
+Wed Jan  7 01:17:36 2004  Matthias Clasen  <maclas@gmx.de>
+
+	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_size_func): 
+	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_set_size): 
+	* gdk-pixbuf-loader.c (gdk_pixbuf_loader_init): Make it possible
+	to call gdk_pixbuf_loader_set_size (loader, 0, 0) by changing
+	the initial values of priv->width/height to -1.
+	
+	* io-tiff.c (tiff_image_parse): 
+	* io-ras.c (RAS2State): 
+	* io-pnm.c (gdk_pixbuf__pnm_image_load_increment): 
+	* io-pcx.c (gdk_pixbuf__pcx_load_increment): 
+	* io-jpeg.c (gdk_pixbuf__jpeg_image_load_increment): 
+	* io-png.c (png_info_callback): 
+	* io-ico.c (DecodeHeader): 
+	* io-bmp.c (DecodeHeader): Call size_func once the size is known,
+	even if the module can't make use of the scaling information. If
+	size_func returns 0, don't allocate a pixbuf and return, if 
+	necessary with an error.
+
+	* gdk-pixbuf.h: 
+	* gdk-pixbuf-io.c (gdk_pixbuf_get_file_info): A new function 
+	to determine the type and size of an image file without loading
+	it completely.  (#53725)
+
 Sun Jan  4 00:44:57 2004  Matthias Clasen  <maclas@gmx.de>
 
 	* gdk-pixbuf.c (gdk_pixbuf_class_init): Turn the pixbuf 
diff --git a/gdk-pixbuf/gdk-pixbuf-io.c b/gdk-pixbuf/gdk-pixbuf-io.c
index dc96b44d2..dc5dc5143 100644
--- a/gdk-pixbuf/gdk-pixbuf-io.c
+++ b/gdk-pixbuf/gdk-pixbuf-io.c
@@ -910,6 +910,93 @@ gdk_pixbuf_new_from_file_at_size (const char *filename,
 	return pixbuf;
 }
 
+static void
+info_cb (GdkPixbufLoader *loader, 
+	 int              width,
+	 int              height,
+	 gpointer         data)
+{
+	struct {
+		GdkPixbufFormat *format;
+		int width;
+		int height;
+	} *info = data;
+
+	g_return_if_fail (width > 0 && height > 0);
+
+	info->format = gdk_pixbuf_loader_get_format (loader);
+	info->width = width;
+	info->height = height;
+
+	gdk_pixbuf_loader_set_size (loader, 0, 0);
+}
+
+/**
+ * gdk_pixbuf_get_file_info:
+ * @filename: The name of the file to identify.
+ * @width: Return location for the width of the image, or %NULL
+ * @height: Return location for the height of the image, or %NULL
+ * 
+ * Parses an image file far enough to determine its format and size.
+ * 
+ * Returns: A #GdkPixbufFormat describing the image format of the file 
+ *    or %NULL if the image format wasn't recognized. The return value 
+ *    is owned by GdkPixbuf and should not be freed.
+ *
+ * Since: 2.4
+ **/
+GdkPixbufFormat *
+gdk_pixbuf_get_file_info (const gchar  *filename,
+			  gint         *width, 
+			  gint         *height)
+{
+	GdkPixbufLoader *loader;
+	GError *temp = NULL;
+	guchar buffer [4096];
+	int length;
+	FILE *f;
+	struct {
+		GdkPixbufFormat *format;
+		gint width;
+		gint height;
+	} info;
+
+	g_return_val_if_fail (filename != NULL, NULL);
+
+	f = fopen (filename, "rb");
+	if (!f)
+		return NULL;
+
+	loader = gdk_pixbuf_loader_new ();
+
+	info.format = NULL;
+	info.width = -1;
+	info.height = -1;
+		
+	g_signal_connect (loader, "size-prepared", G_CALLBACK (info_cb), &info);
+
+	while (!feof (f)) {
+		length = fread (buffer, 1, sizeof (buffer), f);
+		if (length > 0) {
+			if (!gdk_pixbuf_loader_write (loader, buffer, length, NULL))
+				break;
+		}
+		if (info.format != NULL)
+			break;
+	}
+
+	fclose (f);
+	gdk_pixbuf_loader_close (loader, NULL);
+	g_object_unref (G_OBJECT (loader));
+
+	if (width) 
+		*width = info.width;
+	if (height) 
+		*height = info.height;
+
+	return info.format;
+}
+
 /**
  * gdk_pixbuf_new_from_xpm_data:
  * @data: Pointer to inline XPM data.
diff --git a/gdk-pixbuf/gdk-pixbuf-loader.c b/gdk-pixbuf/gdk-pixbuf-loader.c
index b4c135252..d980eea97 100644
--- a/gdk-pixbuf/gdk-pixbuf-loader.c
+++ b/gdk-pixbuf/gdk-pixbuf-loader.c
@@ -208,6 +208,9 @@ gdk_pixbuf_loader_init (GdkPixbufLoader *loader)
         GdkPixbufLoaderPrivate *priv;
   
         priv = g_new0 (GdkPixbufLoaderPrivate, 1);
+        priv->width = -1;
+        priv->height = -1;
+
         loader->priv = priv;
 }
 
@@ -253,7 +256,7 @@ gdk_pixbuf_loader_set_size (GdkPixbufLoader *loader,
 			    gint             height)
 {
         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
-        g_return_if_fail (width > 0 && height > 0);
+        g_return_if_fail (width >= 0 && height >= 0);
 
         if (!priv->size_fixed) 
                 {
@@ -268,7 +271,7 @@ gdk_pixbuf_loader_size_func (gint *width, gint *height, gpointer loader)
         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
 
         /* allow calling gdk_pixbuf_loader_set_size() before the signal */
-        if (priv->width == 0 && priv->height == 0) 
+        if (priv->width == -1 && priv->height == -1) 
                 {
                         priv->width = *width;
                         priv->height = *height;
diff --git a/gdk-pixbuf/gdk-pixbuf.h b/gdk-pixbuf/gdk-pixbuf.h
index 0f5728f33..234f88310 100644
--- a/gdk-pixbuf/gdk-pixbuf.h
+++ b/gdk-pixbuf/gdk-pixbuf.h
@@ -302,6 +302,10 @@ gchar    **gdk_pixbuf_format_get_mime_types  (GdkPixbufFormat *format);
 gchar    **gdk_pixbuf_format_get_extensions  (GdkPixbufFormat *format);
 gboolean   gdk_pixbuf_format_is_writable     (GdkPixbufFormat *format);
 
+GdkPixbufFormat *gdk_pixbuf_get_file_info (const gchar  *filename,
+					   gint         *width, 
+					   gint         *height);
+
 G_END_DECLS
 
 #include <gdk-pixbuf/gdk-pixbuf-loader.h>
diff --git a/gdk-pixbuf/io-bmp.c b/gdk-pixbuf/io-bmp.c
index f7f50df15..8212834e1 100644
--- a/gdk-pixbuf/io-bmp.c
+++ b/gdk-pixbuf/io-bmp.c
@@ -144,6 +144,7 @@ struct bmp_compression_state {
 /* Progressive loading */
 
 struct bmp_progressive_state {
+	GdkPixbufModuleSizeFunc size_func;
 	GdkPixbufModulePreparedFunc prepared_func;
 	GdkPixbufModuleUpdatedFunc updated_func;
 	gpointer user_data;
@@ -319,41 +320,52 @@ static gboolean DecodeHeader(unsigned char *BFH, unsigned char *BIH,
 		State->LineWidth = (State->LineWidth / 4) * 4 + 4;
 
 	if (State->pixbuf == NULL) {
+		if (State->size_func) {
+			gint width = State->Header.width;
+			gint height = State->Header.height;
+
+			(*State->size_func) (&width, &height, State->user_data);
+			if (width == 0 || height == 0) {
+				State->read_state = READ_STATE_DONE;
+				State->BufferSize = 0;
+				return TRUE;
+			}
+		}
+
 		if (State->Type == 32 || 
 		    State->Compressed == BI_RLE4 || 
 		    State->Compressed == BI_RLE8)
 			State->pixbuf =
-			    gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8,
-					   (gint) State->Header.width,
-					   (gint) State->Header.height);
+				gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8,
+					       (gint) State->Header.width,
+					       (gint) State->Header.height);
 		else
 			State->pixbuf =
-			    gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8,
-					   (gint) State->Header.width,
-					   (gint) State->Header.height);
-
-                if (State->pixbuf == NULL) {
-                        g_set_error (error,
-                                     GDK_PIXBUF_ERROR,
-                                     GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
-                                     _("Not enough memory to load bitmap image"));
+				gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8,
+					       (gint) State->Header.width,
+					       (gint) State->Header.height);
+		
+		if (State->pixbuf == NULL) {
+			g_set_error (error,
+				     GDK_PIXBUF_ERROR,
+				     GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
+				     _("Not enough memory to load bitmap image"));
 			State->read_state = READ_STATE_ERROR;
-                        return FALSE;
-                }
-
+			return FALSE;
+			}
+		
 		if (State->prepared_func != NULL)
 			/* Notify the client that we are ready to go */
 			(*State->prepared_func) (State->pixbuf, NULL, State->user_data);
-
+		
+		/* make all pixels initially transparent */
+		if (State->Compressed == BI_RLE4 || State->Compressed == BI_RLE8) {
+			memset (State->pixbuf->pixels, 0, State->pixbuf->rowstride * State->Header.height);
+			State->compr.p = State->pixbuf->pixels 
+				+ State->pixbuf->rowstride * (State->Header.height- 1);
+		}
 	}
 	
-	/* make all pixels initially transparent */
-	if (State->Compressed == BI_RLE4 || State->Compressed == BI_RLE8) {
-		memset (State->pixbuf->pixels, 0, State->pixbuf->rowstride * State->Header.height);
-		State->compr.p = State->pixbuf->pixels 
-			+ State->pixbuf->rowstride * (State->Header.height- 1);
-	}
-
 	State->BufferDone = 0;
 	if (State->Type <= 8) {
 		State->read_state = READ_STATE_PALETTE;
@@ -485,6 +497,7 @@ gdk_pixbuf__bmp_image_begin_load(GdkPixbufModuleSizeFunc size_func,
 	struct bmp_progressive_state *context;
 
 	context = g_new0(struct bmp_progressive_state, 1);
+	context->size_func = size_func;
 	context->prepared_func = prepared_func;
 	context->updated_func = updated_func;
 	context->user_data = user_data;
@@ -1036,6 +1049,9 @@ gdk_pixbuf__bmp_image_load_increment(gpointer data,
 				return FALSE;
 
 			break;
+		case READ_STATE_DONE:
+			return TRUE;
+			break;
 
 		default:
 			g_assert_not_reached ();
diff --git a/gdk-pixbuf/io-ico.c b/gdk-pixbuf/io-ico.c
index 482cff29a..e19f86f8f 100644
--- a/gdk-pixbuf/io-ico.c
+++ b/gdk-pixbuf/io-ico.c
@@ -126,6 +126,7 @@ struct headerpair {
 };
 
 struct ico_progressive_state {
+	GdkPixbufModuleSizeFunc size_func;
 	GdkPixbufModulePreparedFunc prepared_func;
 	GdkPixbufModuleUpdatedFunc updated_func;
 	gpointer user_data;
@@ -400,6 +401,19 @@ static void DecodeHeader(guchar *Data, gint Bytes,
 
 
 	if (State->pixbuf == NULL) {
+#if 1
+		if (State->size_func) {
+			gint width = State->Header.width;
+			gint height = State->Header.height;
+
+			(*State->size_func) (&width, &height, State->user_data);
+			if (width == 0 || height == 0) {
+				State->LineWidth = 0;
+				return;
+			}
+		}
+#endif
+
 		State->pixbuf =
 		    gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8,
 				   State->Header.width,
@@ -445,6 +459,7 @@ gdk_pixbuf__ico_image_begin_load(GdkPixbufModuleSizeFunc size_func,
 	struct ico_progressive_state *context;
 
 	context = g_new0(struct ico_progressive_state, 1);
+	context->size_func = size_func;
 	context->prepared_func = prepared_func;
 	context->updated_func = updated_func;
 	context->user_data = user_data;
@@ -828,6 +843,9 @@ gdk_pixbuf__ico_image_load_increment(gpointer data,
 			GError *decode_err = NULL;
 			DecodeHeader(context->HeaderBuf,
 				     context->HeaderDone, context, &decode_err);
+			if (context->LineBuf != NULL && context->LineWidth == 0)
+				return TRUE;
+
 			if (decode_err) {
 				g_propagate_error (error, decode_err);
 				return FALSE;
diff --git a/gdk-pixbuf/io-jpeg.c b/gdk-pixbuf/io-jpeg.c
index 191372890..85d75dfe6 100644
--- a/gdk-pixbuf/io-jpeg.c
+++ b/gdk-pixbuf/io-jpeg.c
@@ -650,7 +650,12 @@ gdk_pixbuf__jpeg_image_load_increment (gpointer data,
 			
 			width = cinfo->image_width;
 			height = cinfo->image_height;
-			(* context->size_func) (&width, &height, context->user_data);
+			if (context->size_func) {
+				(* context->size_func) (&width, &height, context->user_data);
+				if (width == 0 || height == 0)
+					return FALSE;
+			}
+			
 			for (cinfo->scale_denom = 2; cinfo->scale_denom <= 8; cinfo->scale_denom *= 2) {
 				jpeg_calc_output_dimensions (cinfo);
 				if (cinfo->output_width < width || cinfo->output_height < height) {
diff --git a/gdk-pixbuf/io-pcx.c b/gdk-pixbuf/io-pcx.c
index 5ccbeea5a..4a9d0bef8 100644
--- a/gdk-pixbuf/io-pcx.c
+++ b/gdk-pixbuf/io-pcx.c
@@ -606,8 +606,12 @@ gdk_pixbuf__pcx_load_increment(gpointer data, const guchar *buf, guint size,
 				g_set_error(error, GDK_PIXBUF_ERROR, GDK_PIXBUF_ERROR_CORRUPT_IMAGE, _("Image has invalid width and/or height"));
 				return FALSE;
 			}
-			if(context->size_func)
-				context->size_func(&width, &height, context->user_data);
+			if (context->size_func)
+			  {
+			    (*context->size_func) (&width, &height, context->user_data);
+			    if (width == 0 || height == 0)
+			      return TRUE;
+			  }
 
 			switch(context->bpp) {
 				default:
diff --git a/gdk-pixbuf/io-png.c b/gdk-pixbuf/io-png.c
index 5ddca7510..fa35734a7 100644
--- a/gdk-pixbuf/io-png.c
+++ b/gdk-pixbuf/io-png.c
@@ -358,6 +358,7 @@ struct _LoadContext {
         png_structp png_read_ptr;
         png_infop   png_info_ptr;
 
+        GdkPixbufModuleSizeFunc size_func;
         GdkPixbufModulePreparedFunc prepare_func;
         GdkPixbufModuleUpdatedFunc update_func;
         gpointer notify_user_data;
@@ -398,6 +399,7 @@ gdk_pixbuf__png_image_begin_load (GdkPixbufModuleSizeFunc size_func,
         
         lc->fatal_error_occurred = FALSE;
 
+        lc->size_func = size_func;
         lc->prepare_func = prepare_func;
         lc->update_func = update_func;
         lc->notify_user_data = user_data;
@@ -593,7 +595,18 @@ png_info_callback   (png_structp png_read_ptr,
         if (color_type & PNG_COLOR_MASK_ALPHA)
                 have_alpha = TRUE;
         
-        lc->pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, have_alpha, 8, width, height);
+        if (lc->size_func) {
+                gint w = width;
+                gint h = height;
+                (* lc->size_func) (&w, &h, lc->notify_user_data);
+                
+                if (w == 0 || h == 0) {
+                        lc->fatal_error_occurred = TRUE;
+                        return;
+                }
+        }
+
+        lc->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, have_alpha, 8, width, height);
 
         if (lc->pixbuf == NULL) {
                 /* Failed to allocate memory */
diff --git a/gdk-pixbuf/io-pnm.c b/gdk-pixbuf/io-pnm.c
index 1fc1fe7c0..437ccaf0e 100644
--- a/gdk-pixbuf/io-pnm.c
+++ b/gdk-pixbuf/io-pnm.c
@@ -55,6 +55,7 @@ typedef struct {
 typedef struct {
 	GdkPixbufModuleUpdatedFunc updated_func;
 	GdkPixbufModulePreparedFunc prepared_func;
+	GdkPixbufModuleSizeFunc size_func;
 	gpointer user_data;
 	
 	GdkPixbuf *pixbuf;
@@ -820,6 +821,7 @@ gdk_pixbuf__pnm_image_begin_load (GdkPixbufModuleSizeFunc size_func,
 		return NULL;
 	}
 	memset (context, 0, sizeof (PnmLoaderContext));
+	context->size_func = size_func;
 	context->prepared_func = prepared_func;
 	context->updated_func  = updated_func;
 	context->user_data = user_data;
@@ -944,6 +946,16 @@ gdk_pixbuf__pnm_image_load_increment (gpointer data,
 			
 			context->got_header = TRUE;
 		}
+
+		if (context->size_func) {
+			gint w = context->width;
+			gint h = context->height;
+			(*context->size_func) (&w, &h, context->user_data);
+			
+			if (w == 0 || h == 0) 
+				return FALSE;
+		}
+		
 		
 		/* scan until we hit image data */
 		if (!context->did_prescan) {
diff --git a/gdk-pixbuf/io-ras.c b/gdk-pixbuf/io-ras.c
index fba4b9900..40ba370d5 100644
--- a/gdk-pixbuf/io-ras.c
+++ b/gdk-pixbuf/io-ras.c
@@ -68,6 +68,7 @@ struct rasterfile {
 /* Progressive loading */
 
 struct ras_progressive_state {
+	GdkPixbufModuleSizeFunc size_func;
 	GdkPixbufModulePreparedFunc prepared_func;
 	GdkPixbufModuleUpdatedFunc updated_func;
 	gpointer user_data;
@@ -174,6 +175,15 @@ static gboolean RAS2State(struct rasterfile *RAS,
 
 
 	if (!State->pixbuf) {
+		if (State->size_func) {
+			gint width = State->Header.width;
+			gint height = State->Header.height;
+			
+			(*State->size_func) (&width, &height, State->user_data);
+			if (width == 0 || height == 0)
+				return FALSE;
+		}
+
 		if (State->RasType == 32)
 			State->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8,
 							(gint) State->Header.width,
@@ -227,6 +237,7 @@ gdk_pixbuf__ras_image_begin_load(GdkPixbufModuleSizeFunc size_func,
 	struct ras_progressive_state *context;
 
 	context = g_new0(struct ras_progressive_state, 1);
+	context->size_func = size_func;
 	context->prepared_func = prepared_func;
 	context->updated_func = updated_func;
 	context->user_data = user_data;
diff --git a/gdk-pixbuf/io-tga.c b/gdk-pixbuf/io-tga.c
index 1486d4480..32c6af0b5 100644
--- a/gdk-pixbuf/io-tga.c
+++ b/gdk-pixbuf/io-tga.c
@@ -137,6 +137,7 @@ struct _TGAContext {
 	gboolean prepared;
 	gboolean done;
 
+	GdkPixbufModuleSizeFunc sfunc;
 	GdkPixbufModulePreparedFunc pfunc;
 	GdkPixbufModuleUpdatedFunc ufunc;
 	gpointer udata;
@@ -334,6 +335,16 @@ static gboolean fill_in_context(TGAContext *ctx, GError **err)
 	w = LE16(ctx->hdr->width);
 	h = LE16(ctx->hdr->height);
 
+	if (ctx->sfunc) {
+		gint wi = w;
+		gint hi = h;
+		
+		(*ctx->sfunc) (&wi, &hi, ctx->udata);
+		
+		if (wi == 0 || hi == 0) 
+			return FALSE;
+	}
+
 	ctx->pbuf = get_contiguous_pixbuf (w, h, alpha);
 
 	if (!ctx->pbuf) {
@@ -872,6 +883,7 @@ static gpointer gdk_pixbuf__tga_begin_load(GdkPixbufModuleSizeFunc f0,
 	ctx->prepared = FALSE;
 	ctx->done = FALSE;
 
+	ctx->sfunc = f0;
 	ctx->pfunc = f1;
 	ctx->ufunc = f2;
 	ctx->udata = udata;
diff --git a/gdk-pixbuf/io-tiff.c b/gdk-pixbuf/io-tiff.c
index 3e6d9fca0..2d47f6594 100644
--- a/gdk-pixbuf/io-tiff.c
+++ b/gdk-pixbuf/io-tiff.c
@@ -47,6 +47,7 @@
 typedef struct _TiffContext TiffContext;
 struct _TiffContext
 {
+	GdkPixbufModuleSizeFunc size_func;
 	GdkPixbufModulePreparedFunc prepare_func;
 	GdkPixbufModuleUpdatedFunc update_func;
 	gpointer user_data;
@@ -225,6 +226,15 @@ tiff_image_parse (TIFF *tiff, TiffContext *context, GError **error)
                 return NULL;                
         }
 
+	if (context && context->size_func) {
+                gint w = width;
+                gint h = height;
+		(* context->size_func) (&w, &h, context->user_data);
+                
+                if (w == 0 || h == 0)
+                    return NULL;
+        }
+
         pixels = g_try_malloc (bytes);
 
         if (!pixels) {
@@ -370,6 +380,7 @@ gdk_pixbuf__tiff_image_begin_load (GdkPixbufModuleSizeFunc size_func,
 	TiffContext *context;
         
 	context = g_new0 (TiffContext, 1);
+	context->size_func = size_func;
 	context->prepare_func = prepare_func;
 	context->update_func = update_func;
 	context->user_data = user_data;