1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
3 /* GdkPixbuf library - Main header file
5 * Copyright (C) 1999 The Free Software Foundation
7 * Authors: Mark Crichton <crichton@gimp.org>
8 * Miguel de Icaza <miguel@gnu.org>
9 * Federico Mena-Quintero <federico@gimp.org>
10 * Jonathan Blandford <jrb@redhat.com>
12 * This library is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU Library General Public
14 * License as published by the Free Software Foundation; either
15 * version 2 of the License, or (at your option) any later version.
17 * This library is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * Library General Public License for more details.
22 * You should have received a copy of the GNU Library General Public
23 * License along with this library; if not, write to the
24 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
25 * Boston, MA 02111-1307, USA.
29 #include <gtk/gtksignal.h>
30 #include "gdk-pixbuf-loader.h"
31 #include "gdk-pixbuf-io.h"
42 static GtkObjectClass *parent_class;
44 static void gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *klass);
45 static void gdk_pixbuf_loader_init (GdkPixbufLoader *loader);
46 static void gdk_pixbuf_loader_destroy (GtkObject *loader);
47 static void gdk_pixbuf_loader_finalize (GtkObject *loader);
49 static guint pixbuf_loader_signals[LAST_SIGNAL] = { 0 };
55 #define LOADER_HEADER_SIZE 128
59 GdkPixbufAnimation *animation;
61 guchar header_buf[LOADER_HEADER_SIZE];
62 gint header_buf_offset;
63 GdkPixbufModule *image_module;
65 } GdkPixbufLoaderPrivate;
70 typedef void (* GtkSignal_NONE__INT_INT_INT_INT) (GtkObject *object,
71 gint arg1, gint arg2, gint arg3, gint arg4,
74 gtk_marshal_NONE__INT_INT_INT_INT (GtkObject *object, GtkSignalFunc func, gpointer func_data,
77 GtkSignal_NONE__INT_INT_INT_INT rfunc;
79 rfunc = (GtkSignal_NONE__INT_INT_INT_INT) func;
81 GTK_VALUE_INT (args[0]),
82 GTK_VALUE_INT (args[1]),
83 GTK_VALUE_INT (args[2]),
84 GTK_VALUE_INT (args[3]),
91 * gdk_pixbuf_loader_get_type:
94 * Registers the #GdkPixubfLoader class if necessary, and returns the type ID
97 * Return value: The type ID of the #GdkPixbufLoader class.
100 gdk_pixbuf_loader_get_type (void)
102 static GtkType loader_type = 0;
105 static const GtkTypeInfo loader_info = {
107 sizeof (GdkPixbufLoader),
108 sizeof (GdkPixbufLoaderClass),
109 (GtkClassInitFunc) gdk_pixbuf_loader_class_init,
110 (GtkObjectInitFunc) gdk_pixbuf_loader_init,
111 /* reserved_1 */ NULL,
112 /* reserved_2 */ NULL,
113 (GtkClassInitFunc) NULL,
116 loader_type = gtk_type_unique (GTK_TYPE_OBJECT, &loader_info);
123 gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *class)
125 GtkObjectClass *object_class;
127 object_class = (GtkObjectClass *) class;
129 parent_class = gtk_type_class (gtk_object_get_type ());
131 pixbuf_loader_signals[AREA_PREPARED] =
132 gtk_signal_new ("area_prepared",
135 GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, area_prepared),
136 gtk_marshal_NONE__NONE,
139 pixbuf_loader_signals[AREA_UPDATED] =
140 gtk_signal_new ("area_updated",
143 GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, area_updated),
144 gtk_marshal_NONE__INT_INT_INT_INT,
151 pixbuf_loader_signals[CLOSED] =
152 gtk_signal_new ("closed",
155 GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, closed),
156 gtk_marshal_NONE__NONE,
159 gtk_object_class_add_signals (object_class, pixbuf_loader_signals, LAST_SIGNAL);
161 object_class->destroy = gdk_pixbuf_loader_destroy;
162 object_class->finalize = gdk_pixbuf_loader_finalize;
166 gdk_pixbuf_loader_init (GdkPixbufLoader *loader)
168 GdkPixbufLoaderPrivate *priv;
170 priv = g_new0 (GdkPixbufLoaderPrivate, 1);
171 loader->private = priv;
175 gdk_pixbuf_loader_destroy (GtkObject *object)
177 GdkPixbufLoader *loader;
178 GdkPixbufLoaderPrivate *priv = NULL;
180 g_return_if_fail (object != NULL);
181 g_return_if_fail (GDK_IS_PIXBUF_LOADER (object));
183 loader = GDK_PIXBUF_LOADER (object);
184 priv = loader->private;
187 gdk_pixbuf_loader_close (loader);
190 gdk_pixbuf_unref (priv->pixbuf);
192 if (GTK_OBJECT_CLASS (parent_class)->destroy)
193 (* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
197 gdk_pixbuf_loader_finalize (GtkObject *object)
199 GdkPixbufLoader *loader;
200 GdkPixbufLoaderPrivate *priv = NULL;
202 loader = GDK_PIXBUF_LOADER (object);
203 priv = loader->private;
207 if (GTK_OBJECT_CLASS (parent_class)->finalize)
208 (* GTK_OBJECT_CLASS (parent_class)->finalize) (object);
212 gdk_pixbuf_loader_prepare (GdkPixbuf *pixbuf, gpointer loader)
214 GdkPixbufLoaderPrivate *priv = NULL;
216 priv = GDK_PIXBUF_LOADER (loader)->private;
217 gdk_pixbuf_ref (pixbuf);
218 g_assert (priv->pixbuf == NULL);
220 priv->pixbuf = pixbuf;
221 gtk_signal_emit (GTK_OBJECT (loader), pixbuf_loader_signals[AREA_PREPARED]);
225 gdk_pixbuf_loader_update (GdkPixbuf *pixbuf, guint x, guint y, guint width, guint height, gpointer loader)
227 GdkPixbufLoaderPrivate *priv = NULL;
229 priv = GDK_PIXBUF_LOADER (loader)->private;
231 gtk_signal_emit (GTK_OBJECT (loader),
232 pixbuf_loader_signals[AREA_UPDATED],
234 /* sanity check in here. Defend against an errant loader */
235 MIN (width, gdk_pixbuf_get_width (priv->pixbuf)),
236 MIN (height, gdk_pixbuf_get_height (priv->pixbuf)));
242 * gdk_pixbuf_loader_new:
245 * Creates a new pixbuf loader object.
247 * Return value: A newly-created pixbuf loader.
250 gdk_pixbuf_loader_new (void)
252 return gtk_type_new (gdk_pixbuf_loader_get_type ());
256 gdk_pixbuf_loader_load_module(GdkPixbufLoader *loader)
258 GdkPixbufLoaderPrivate *priv = loader->private;
260 priv->image_module = gdk_pixbuf_get_module (priv->header_buf, priv->header_buf_offset);
262 if (priv->image_module == NULL)
265 if (priv->image_module->module == NULL)
266 gdk_pixbuf_load_module (priv->image_module);
268 if (priv->image_module->module == NULL)
271 if ((priv->image_module->begin_load == NULL) ||
272 (priv->image_module->stop_load == NULL) ||
273 (priv->image_module->load_increment == NULL)) {
274 g_warning ("module %s does not support incremental loading.\n",
275 priv->image_module->module_name);
279 priv->context = (*priv->image_module->begin_load) (gdk_pixbuf_loader_prepare, gdk_pixbuf_loader_update, NULL, NULL, loader);
281 if (priv->context == NULL) {
282 g_warning("Failed to begin progressive load");
286 if( (* priv->image_module->load_increment) (priv->context, priv->header_buf, priv->header_buf_offset) )
287 return priv->header_buf_offset;
293 gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, const guchar *buf, size_t count)
296 GdkPixbufLoaderPrivate *priv = loader->private;
298 nbytes = MIN(LOADER_HEADER_SIZE - priv->header_buf_offset, count);
299 memcpy (priv->header_buf + priv->header_buf_offset, buf, nbytes);
301 priv->header_buf_offset += nbytes;
303 if(priv->header_buf_offset >= LOADER_HEADER_SIZE) {
304 if (gdk_pixbuf_loader_load_module(loader) == 0)
311 * gdk_pixbuf_loader_write:
312 * @loader: A pixbuf loader.
313 * @buf: Pointer to image data.
314 * @count: Length of the @buf buffer in bytes.
316 * This will cause a pixbuf loader to parse the next @count bytes of an image.
317 * It will return TRUE if the data was loaded successfully, and FALSE if an
318 * error occurred. In the latter case, the loader will be closed, and will not
319 * accept further writes.
321 * Return value: #TRUE if the write was successful, or #FALSE if the loader
322 * cannot parse the buffer.
325 gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const guchar *buf, size_t count)
327 GdkPixbufLoaderPrivate *priv;
329 g_return_val_if_fail (loader != NULL, FALSE);
330 g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), FALSE);
332 g_return_val_if_fail (buf != NULL, FALSE);
333 g_return_val_if_fail (count >= 0, FALSE);
335 priv = loader->private;
337 /* we expect it's not to be closed */
338 g_return_val_if_fail (priv->closed == FALSE, FALSE);
340 if (priv->image_module == NULL) {
343 eaten = gdk_pixbuf_loader_eat_header_write(loader, buf, count);
351 if (count > 0 && priv->image_module->load_increment)
352 return (* priv->image_module->load_increment) (priv->context, buf, count);
358 * gdk_pixbuf_loader_get_pixbuf:
359 * @loader: A pixbuf loader.
361 * Queries the GdkPixbuf that a pixbuf loader is currently creating. In general
362 * it only makes sense to call this function afer the "area_prepared" signal has
363 * been emitted by the loader; this means that enough data has been read to know
364 * the size of the image that will be allocated. If the loader has not received
365 * enough data via gdk_pixbuf_loader_write(), then this function returns NULL.
366 * The returned pixbuf will be the same in all future calls to the loader, so
367 * simply calling gdk_pixbuf_ref() should be sufficient to continue using it.
369 * Return value: The GdkPixbuf that the loader is creating, or NULL if not
370 * enough data has been read to determine how to create the image buffer.
373 gdk_pixbuf_loader_get_pixbuf (GdkPixbufLoader *loader)
375 GdkPixbufLoaderPrivate *priv;
377 g_return_val_if_fail (loader != NULL, NULL);
378 g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL);
380 priv = loader->private;
386 * gdk_pixbuf_loader_get_animation:
387 * @loader: A pixbuf loader
389 * Queries the GdkPixbufAnimation that a pixbuf loader is currently creating.
390 * In general it only makes sense to call this function afer the "area_prepared"
391 * signal has been emitted by the loader.
393 * Return value: The GdkPixbufAnimation that the loader is loading, or NULL if
394 not enough data has been read to determine the information.
397 gdk_pixbuf_loader_get_animation (GdkPixbufLoader *loader)
399 GdkPixbufLoaderPrivate *priv;
401 g_return_val_if_fail (loader != NULL, NULL);
402 g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL);
404 priv = loader->private;
406 return priv->animation;
410 * gdk_pixbuf_loader_close:
411 * @loader: A pixbuf loader.
413 * Informs a pixbuf loader that no further writes with gdk_pixbuf_load_write()
414 * will occur, so that it can free its internal loading structures.
417 gdk_pixbuf_loader_close (GdkPixbufLoader *loader)
419 GdkPixbufLoaderPrivate *priv;
421 g_return_if_fail (loader != NULL);
422 g_return_if_fail (GDK_IS_PIXBUF_LOADER (loader));
424 priv = loader->private;
426 /* we expect it's not closed */
427 g_return_if_fail (priv->closed == FALSE);
429 /* We have less the 128 bytes in the image. Flush it, and keep going. */
430 if (priv->image_module == NULL)
431 gdk_pixbuf_loader_load_module (loader);
433 if (priv->image_module && priv->image_module->stop_load)
434 (* priv->image_module->stop_load) (priv->context);
438 gtk_signal_emit (GTK_OBJECT (loader),
439 pixbuf_loader_signals[CLOSED]);