Pileus Git - ~andy/gtk/blob - gdk-pixbuf/gdk-pixbuf-loader.c

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -*- */
   2 /* GdkPixbuf library - Progressive loader object
   3  *
   4  * Copyright (C) 1999 The Free Software Foundation
   5  *
   6  * Authors: Mark Crichton <crichton@gimp.org>
   7  *          Miguel de Icaza <miguel@gnu.org>
   8  *          Federico Mena-Quintero <federico@gimp.org>
   9  *          Jonathan Blandford <jrb@redhat.com>
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2 of the License, or (at your option) any later version.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the
  23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24  * Boston, MA 02111-1307, USA.
  25  */
  26
  27 #include <config.h>
  28 #include <string.h>
  29
  30 #include "gdk-pixbuf-private.h"
  31 #include "gdk-pixbuf-animation.h"
  32 #include "gdk-pixbuf-io.h"
  33 #include "gdk-pixbuf-loader.h"
  34 #include "gdk-pixbuf-marshal.h"
  35 #include "gdk-pixbuf-alias.h"
  36
  37 enum {
  38         SIZE_PREPARED,
  39         AREA_PREPARED,
  40         AREA_UPDATED,
  41         CLOSED,
  42         LAST_SIGNAL
  43 };
  44
  45
  46 static void gdk_pixbuf_loader_finalize (GObject *loader);
  47
  48 static guint    pixbuf_loader_signals[LAST_SIGNAL] = { 0 };
  49
  50 /* Internal data */
  51
  52 #define LOADER_HEADER_SIZE 1024
  53
  54 typedef struct
  55 {
  56         GdkPixbufAnimation *animation;
  57         gboolean closed;
  58         gboolean holds_threadlock;
  59         guchar header_buf[LOADER_HEADER_SIZE];
  60         gint header_buf_offset;
  61         GdkPixbufModule *image_module;
  62         gpointer context;
  63         gint width;
  64         gint height;
  65         gboolean size_fixed;
  66         gboolean needs_scale;
  67 } GdkPixbufLoaderPrivate;
  68
  69 G_DEFINE_TYPE (GdkPixbufLoader, gdk_pixbuf_loader, G_TYPE_OBJECT)
  70
  71 static void
  72 gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *class)
  73 {
  74         GObjectClass *object_class;
  75
  76         object_class = (GObjectClass *) class;
  77
  78         object_class->finalize = gdk_pixbuf_loader_finalize;
  79
  80         /**
  81          * GdkPixbufLoader::size-prepared:
  82          * @loader: the object which received the signal.
  83          * @width: the original width of the image
  84          * @height: the original height of the image
  85          *
  86          * This signal is emitted when the pixbuf loader has been fed the
  87          * initial amount of data that is required to figure out the size
  88          * of the image that it will create.  Applications can call
  89          * gdk_pixbuf_loader_set_size() in response to this signal to set
  90          * the desired size to which the image should be scaled.
  91          */
  92         pixbuf_loader_signals[SIZE_PREPARED] =
  93                 g_signal_new ("size_prepared",
  94                               G_TYPE_FROM_CLASS (object_class),
  95                               G_SIGNAL_RUN_LAST,
  96                               G_STRUCT_OFFSET (GdkPixbufLoaderClass, size_prepared),
  97                               NULL, NULL,
  98                               _gdk_pixbuf_marshal_VOID__INT_INT,
  99                               G_TYPE_NONE, 2,
 100                               G_TYPE_INT,
 101                               G_TYPE_INT);
 102
 103         /**
 104          * GdkPixbufLoader::area-prepared:
 105          * @loader: the object which received the signal.
 106          *
 107          * This signal is emitted when the pixbuf loader has allocated the
 108          * pixbuf in the desired size.  After this signal is emitted,
 109          * applications can call gdk_pixbuf_loader_get_pixbuf() to fetch
 110          * the partially-loaded pixbuf.
 111          */
 112         pixbuf_loader_signals[AREA_PREPARED] =
 113                 g_signal_new ("area_prepared",
 114                               G_TYPE_FROM_CLASS (object_class),
 115                               G_SIGNAL_RUN_LAST,
 116                               G_STRUCT_OFFSET (GdkPixbufLoaderClass, area_prepared),
 117                               NULL, NULL,
 118                               _gdk_pixbuf_marshal_VOID__VOID,
 119                               G_TYPE_NONE, 0);
 120
 121         /**
 122          * GdkPixbufLoader::area-updated:
 123          * @loader: the object which received the signal.
 124          * @x: X offset of upper-left corner of the updated area.
 125          * @y: Y offset of upper-left corner of the updated area.
 126          * @width: Width of updated area.
 127          * @height: Height of updated area.
 128          *
 129          * This signal is emitted when a significant area of the image being
 130          * loaded has been updated.  Normally it means that a complete
 131          * scanline has been read in, but it could be a different area as
 132          * well.  Applications can use this signal to know when to repaint
 133          * areas of an image that is being loaded.
 134          */
 135         pixbuf_loader_signals[AREA_UPDATED] =
 136                 g_signal_new ("area_updated",
 137                               G_TYPE_FROM_CLASS (object_class),
 138                               G_SIGNAL_RUN_LAST,
 139                               G_STRUCT_OFFSET (GdkPixbufLoaderClass, area_updated),
 140                               NULL, NULL,
 141                               _gdk_pixbuf_marshal_VOID__INT_INT_INT_INT,
 142                               G_TYPE_NONE, 4,
 143                               G_TYPE_INT,
 144                               G_TYPE_INT,
 145                               G_TYPE_INT,
 146                               G_TYPE_INT);
 147
 148         /**
 149          * GdkPixbufLoader::closed:
 150          * @loader: the object which received the signal.
 151          *
 152          * This signal is emitted when gdk_pixbuf_loader_close() is called.
 153          * It can be used by different parts of an application to receive
 154          * notification when an image loader is closed by the code that
 155          * drives it.
 156          */
 157         pixbuf_loader_signals[CLOSED] =
 158                 g_signal_new ("closed",
 159                               G_TYPE_FROM_CLASS (object_class),
 160                               G_SIGNAL_RUN_LAST,
 161                               G_STRUCT_OFFSET (GdkPixbufLoaderClass, closed),
 162                               NULL, NULL,
 163                               _gdk_pixbuf_marshal_VOID__VOID,
 164                               G_TYPE_NONE, 0);
 165 }
 166
 167 static void
 168 gdk_pixbuf_loader_init (GdkPixbufLoader *loader)
 169 {
 170         GdkPixbufLoaderPrivate *priv;
 171
 172         priv = g_new0 (GdkPixbufLoaderPrivate, 1);
 173         priv->width = -1;
 174         priv->height = -1;
 175
 176         loader->priv = priv;
 177 }
 178
 179 static void
 180 gdk_pixbuf_loader_finalize (GObject *object)
 181 {
 182         GdkPixbufLoader *loader;
 183         GdkPixbufLoaderPrivate *priv = NULL;
 184
 185         loader = GDK_PIXBUF_LOADER (object);
 186         priv = loader->priv;
 187
 188         if (!priv->closed) {
 189                 g_warning ("GdkPixbufLoader finalized without calling gdk_pixbuf_loader_close() - this is not allowed. You must explicitly end the data stream to the loader before dropping the last reference.");
 190                 if (priv->holds_threadlock) {
 191                         _gdk_pixbuf_unlock (priv->image_module);
 192                 }
 193         }
 194         if (priv->animation)
 195                 g_object_unref (priv->animation);
 196
 197         g_free (priv);
 198
 199         G_OBJECT_CLASS (gdk_pixbuf_loader_parent_class)->finalize (object);
 200 }
 201
 202 /**
 203  * gdk_pixbuf_loader_set_size:
 204  * @loader: A pixbuf loader.
 205  * @width: The desired width of the image being loaded.
 206  * @height: The desired height of the image being loaded.
 207  *
 208  * Causes the image to be scaled while it is loaded. The desired
 209  * image size can be determined relative to the original size of
 210  * the image by calling gdk_pixbuf_loader_set_size() from a
 211  * signal handler for the ::size_prepared signal.
 212  *
 213  * Attempts to set the desired image size  are ignored after the
 214  * emission of the ::size_prepared signal.
 215  *
 216  * Since: 2.2
 217  */
 218 void
 219 gdk_pixbuf_loader_set_size (GdkPixbufLoader *loader,
 220                             gint             width,
 221                             gint             height)
 222 {
 223         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
 224         g_return_if_fail (width >= 0 && height >= 0);
 225
 226         if (!priv->size_fixed)
 227                 {
 228                         priv->width = width;
 229                         priv->height = height;
 230                 }
 231 }
 232
 233 static void
 234 gdk_pixbuf_loader_size_func (gint *width, gint *height, gpointer loader)
 235 {
 236         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
 237
 238         /* allow calling gdk_pixbuf_loader_set_size() before the signal */
 239         if (priv->width == -1 && priv->height == -1)
 240                 {
 241                         priv->width = *width;
 242                         priv->height = *height;
 243                 }
 244
 245         g_signal_emit (loader, pixbuf_loader_signals[SIZE_PREPARED], 0, *width, *height);
 246         priv->size_fixed = TRUE;
 247
 248         *width = priv->width;
 249         *height = priv->height;
 250 }
 251
 252 static void
 253 gdk_pixbuf_loader_prepare (GdkPixbuf          *pixbuf,
 254                            GdkPixbufAnimation *anim,
 255                            gpointer            loader)
 256 {
 257         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
 258         g_return_if_fail (pixbuf != NULL);
 259
 260         if (!priv->size_fixed)
 261                 {
 262                         /* Defend against lazy loaders which don't call size_func */
 263                         gint width = gdk_pixbuf_get_width (pixbuf);
 264                         gint height = gdk_pixbuf_get_height (pixbuf);
 265
 266                         gdk_pixbuf_loader_size_func (&width, &height, loader);
 267                 }
 268
 269         priv->needs_scale = FALSE;
 270         if (priv->width > 0 && priv->height > 0 &&
 271             (priv->width != gdk_pixbuf_get_width (pixbuf) ||
 272              priv->height != gdk_pixbuf_get_height (pixbuf)))
 273                 priv->needs_scale = TRUE;
 274
 275         if (anim)
 276                 g_object_ref (anim);
 277         else
 278                 anim = gdk_pixbuf_non_anim_new (pixbuf);
 279
 280         priv->animation = anim;
 281
 282         if (!priv->needs_scale)
 283                 g_signal_emit (loader, pixbuf_loader_signals[AREA_PREPARED], 0);
 284 }
 285
 286 static void
 287 gdk_pixbuf_loader_update (GdkPixbuf *pixbuf,
 288                           gint       x,
 289                           gint       y,
 290                           gint       width,
 291                           gint       height,
 292                           gpointer   loader)
 293 {
 294         GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
 295
 296         if (!priv->needs_scale)
 297                 g_signal_emit (loader,
 298                                pixbuf_loader_signals[AREA_UPDATED],
 299                                0,
 300                                x, y,
 301                                /* sanity check in here.  Defend against an errant loader */
 302                                MIN (width, gdk_pixbuf_animation_get_width (priv->animation)),
 303                                MIN (height, gdk_pixbuf_animation_get_height (priv->animation)));
 304 }
 305
 306 /* Defense against broken loaders; DO NOT take this as a GError example! */
 307 static void
 308 gdk_pixbuf_loader_ensure_error (GdkPixbufLoader *loader,
 309                                 GError         **error)
 310 {
 311         GdkPixbufLoaderPrivate *priv = loader->priv;
 312
 313         if (error == NULL || *error != NULL)
 314                 return;
 315
 316         g_warning ("Bug! loader '%s' didn't set an error on failure",
 317                    priv->image_module->module_name);
 318         g_set_error (error,
 319                      GDK_PIXBUF_ERROR,
 320                      GDK_PIXBUF_ERROR_FAILED,
 321                      _("Internal error: Image loader module '%s' failed to"
 322                        " complete an operation, but didn't give a reason for"
 323                        " the failure"),
 324                      priv->image_module->module_name);
 325 }
 326
 327 static gint
 328 gdk_pixbuf_loader_load_module (GdkPixbufLoader *loader,
 329                                const char      *image_type,
 330                                GError         **error)
 331 {
 332         GdkPixbufLoaderPrivate *priv = loader->priv;
 333
 334         if (image_type)
 335                 {
 336                         priv->image_module = _gdk_pixbuf_get_named_module (image_type,
 337                                                                            error);
 338                 }
 339         else
 340                 {
 341                         priv->image_module = _gdk_pixbuf_get_module (priv->header_buf,
 342                                                                      priv->header_buf_offset,
 343                                                                      NULL,
 344                                                                      error);
 345                 }
 346
 347         if (priv->image_module == NULL)
 348                 return 0;
 349
 350         if (priv->image_module->module == NULL)
 351                 if (!_gdk_pixbuf_load_module (priv->image_module, error))
 352                         return 0;
 353
 354         if (priv->image_module->module == NULL)
 355                 return 0;
 356
 357         if ((priv->image_module->begin_load == NULL) ||
 358             (priv->image_module->stop_load == NULL) ||
 359             (priv->image_module->load_increment == NULL))
 360                 {
 361                         g_set_error (error,
 362                                      GDK_PIXBUF_ERROR,
 363                                      GDK_PIXBUF_ERROR_UNSUPPORTED_OPERATION,
 364                                      _("Incremental loading of image type '%s' is not supported"),
 365                                      priv->image_module->module_name);
 366
 367                         return 0;
 368                 }
 369
 370         if (!priv->holds_threadlock) {
 371                 priv->holds_threadlock = _gdk_pixbuf_lock (priv->image_module);
 372         }
 373
 374         priv->context = priv->image_module->begin_load (gdk_pixbuf_loader_size_func,
 375                                                         gdk_pixbuf_loader_prepare,
 376                                                         gdk_pixbuf_loader_update,
 377                                                         loader,
 378                                                         error);
 379
 380         if (priv->context == NULL)
 381                 {
 382                         gdk_pixbuf_loader_ensure_error (loader, error);
 383                         return 0;
 384                 }
 385
 386         if (priv->header_buf_offset
 387             && priv->image_module->load_increment (priv->context, priv->header_buf, priv->header_buf_offset, error))
 388                 return priv->header_buf_offset;
 389
 390         return 0;
 391 }
 392
 393 static int
 394 gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader,
 395                                     const guchar    *buf,
 396                                     gsize            count,
 397                                     GError         **error)
 398 {
 399         gint n_bytes;
 400         GdkPixbufLoaderPrivate *priv = loader->priv;
 401
 402         n_bytes = MIN(LOADER_HEADER_SIZE - priv->header_buf_offset, count);
 403         memcpy (priv->header_buf + priv->header_buf_offset, buf, n_bytes);
 404
 405         priv->header_buf_offset += n_bytes;
 406
 407         if (priv->header_buf_offset >= LOADER_HEADER_SIZE)
 408                 {
 409                         if (gdk_pixbuf_loader_load_module (loader, NULL, error) == 0)
 410                                 return 0;
 411                 }
 412
 413         return n_bytes;
 414 }
 415
 416 /**
 417  * gdk_pixbuf_loader_write:
 418  * @loader: A pixbuf loader.
 419  * @buf: Pointer to image data.
 420  * @count: Length of the @buf buffer in bytes.
 421  * @error: return location for errors
 422  *
 423  * This will cause a pixbuf loader to parse the next @count bytes of
 424  * an image.  It will return %TRUE if the data was loaded successfully,
 425  * and %FALSE if an error occurred.  In the latter case, the loader
 426  * will be closed, and will not accept further writes. If %FALSE is
 427  * returned, @error will be set to an error from the #GDK_PIXBUF_ERROR
 428  * or #G_FILE_ERROR domains.
 429  *
 430  * Return value: %TRUE if the write was successful, or %FALSE if the loader
 431  * cannot parse the buffer.
 432  **/
 433 gboolean
 434 gdk_pixbuf_loader_write (GdkPixbufLoader *loader,
 435                          const guchar    *buf,
 436                          gsize            count,
 437                          GError         **error)
 438 {
 439         GdkPixbufLoaderPrivate *priv;
 440
 441         g_return_val_if_fail (loader != NULL, FALSE);
 442         g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), FALSE);
 443
 444         g_return_val_if_fail (buf != NULL, FALSE);
 445         g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 446
 447         priv = loader->priv;
 448
 449         /* we expect it's not to be closed */
 450         g_return_val_if_fail (priv->closed == FALSE, FALSE);
 451
 452         if (count > 0 && priv->image_module == NULL)
 453                 {
 454                         gint eaten;
 455
 456                         eaten = gdk_pixbuf_loader_eat_header_write (loader, buf, count, error);
 457                         if (eaten <= 0)
 458                                goto fail;
 459
 460                         count -= eaten;
 461                         buf += eaten;
 462                 }
 463
 464         if (count > 0 && priv->image_module->load_increment)
 465                 {
 466                         if (!priv->image_module->load_increment (priv->context, buf, count,
 467                                                                  error))
 468                                 goto fail;
 469                 }
 470
 471         return TRUE;
 472
 473  fail:
 474         gdk_pixbuf_loader_ensure_error (loader, error);
 475         gdk_pixbuf_loader_close (loader, NULL);
 476
 477         return FALSE;
 478 }
 479
 480 /**
 481  * gdk_pixbuf_loader_new:
 482  *
 483  * Creates a new pixbuf loader object.
 484  *
 485  * Return value: A newly-created pixbuf loader.
 486  **/
 487 GdkPixbufLoader *
 488 gdk_pixbuf_loader_new (void)
 489 {
 490         return g_object_new (GDK_TYPE_PIXBUF_LOADER, NULL);
 491 }
 492
 493 /**
 494  * gdk_pixbuf_loader_new_with_type:
 495  * @image_type: name of the image format to be loaded with the image
 496  * @error: return location for an allocated #GError, or %NULL to ignore errors
 497  *
 498  * Creates a new pixbuf loader object that always attempts to parse
 499  * image data as if it were an image of type @image_type, instead of
 500  * identifying the type automatically. Useful if you want an error if
 501  * the image isn't the expected type, for loading image formats
 502  * that can't be reliably identified by looking at the data, or if
 503  * the user manually forces a specific type.
 504  *
 505  * The list of supported image formats depends on what image loaders
 506  * are installed, but typically "png", "jpeg", "gif", "tiff" and
 507  * "xpm" are among the supported formats. To obtain the full list of
 508  * supported image formats, call gdk_pixbuf_format_get_name() on each
 509  * of the #GdkPixbufFormat structs returned by gdk_pixbuf_get_formats().
 510  *
 511  * Return value: A newly-created pixbuf loader.
 512  **/
 513 GdkPixbufLoader *
 514 gdk_pixbuf_loader_new_with_type (const char *image_type,
 515                                  GError    **error)
 516 {
 517         GdkPixbufLoader *retval;
 518         GError *tmp;
 519         g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 520
 521         retval = g_object_new (GDK_TYPE_PIXBUF_LOADER, NULL);
 522
 523         tmp = NULL;
 524         gdk_pixbuf_loader_load_module (retval, image_type, &tmp);
 525         if (tmp != NULL)
 526                 {
 527                         g_propagate_error (error, tmp);
 528                         gdk_pixbuf_loader_close (retval, NULL);
 529                         g_object_unref (retval);
 530                         return NULL;
 531                 }
 532
 533         return retval;
 534 }
 535
 536 /**
 537  * gdk_pixbuf_loader_new_with_mime_type:
 538  * @mime_type: the mime type to be loaded
 539  * @error: return location for an allocated #GError, or %NULL to ignore errors
 540  *
 541  * Creates a new pixbuf loader object that always attempts to parse
 542  * image data as if it were an image of mime type @mime_type, instead of
 543  * identifying the type automatically. Useful if you want an error if
 544  * the image isn't the expected mime type, for loading image formats
 545  * that can't be reliably identified by looking at the data, or if
 546  * the user manually forces a specific mime type.
 547  *
 548  * The list of supported mime types depends on what image loaders
 549  * are installed, but typically "image/png", "image/jpeg", "image/gif",
 550  * "image/tiff" and "image/x-xpixmap" are among the supported mime types.
 551  * To obtain the full list of supported mime types, call
 552  * gdk_pixbuf_format_get_mime_types() on each of the #GdkPixbufFormat
 553  * structs returned by gdk_pixbuf_get_formats().
 554  *
 555  * Return value: A newly-created pixbuf loader.
 556  * Since: 2.4
 557  **/
 558 GdkPixbufLoader *
 559 gdk_pixbuf_loader_new_with_mime_type (const char *mime_type,
 560                                       GError    **error)
 561 {
 562         const char * image_type = NULL;
 563         char ** mimes;
 564
 565         GdkPixbufLoader *retval;
 566         GError *tmp;
 567
 568         GSList * formats;
 569         GdkPixbufFormat *info;
 570         int i, j, length;
 571
 572         formats = gdk_pixbuf_get_formats ();
 573         length = g_slist_length (formats);
 574
 575         for (i = 0; i < length && image_type == NULL; i++) {
 576                 info = (GdkPixbufFormat *)g_slist_nth_data (formats, i);
 577                 mimes = info->mime_types;
 578
 579                 for (j = 0; mimes[j] != NULL; j++)
 580                         if (g_ascii_strcasecmp (mimes[j], mime_type) == 0) {
 581                                 image_type = info->name;
 582                                 break;
 583                         }
 584         }
 585
 586         g_slist_free (formats);
 587
 588         retval = g_object_new (GDK_TYPE_PIXBUF_LOADER, NULL);
 589
 590         tmp = NULL;
 591         gdk_pixbuf_loader_load_module (retval, image_type, &tmp);
 592         if (tmp != NULL)
 593                 {
 594                         g_propagate_error (error, tmp);
 595                         gdk_pixbuf_loader_close (retval, NULL);
 596                         g_object_unref (retval);
 597                         return NULL;
 598                 }
 599
 600         return retval;
 601 }
 602
 603 /**
 604  * gdk_pixbuf_loader_get_pixbuf:
 605  * @loader: A pixbuf loader.
 606  *
 607  * Queries the #GdkPixbuf that a pixbuf loader is currently creating.
 608  * In general it only makes sense to call this function after the
 609  * "area_prepared" signal has been emitted by the loader; this means
 610  * that enough data has been read to know the size of the image that
 611  * will be allocated.  If the loader has not received enough data via
 612  * gdk_pixbuf_loader_write(), then this function returns %NULL.  The
 613  * returned pixbuf will be the same in all future calls to the loader,
 614  * so simply calling g_object_ref() should be sufficient to continue
 615  * using it.  Additionally, if the loader is an animation, it will
 616  * return the "static image" of the animation
 617  * (see gdk_pixbuf_animation_get_static_image()).
 618  *
 619  * Return value: The #GdkPixbuf that the loader is creating, or %NULL if not
 620  * enough data has been read to determine how to create the image buffer.
 621  **/
 622 GdkPixbuf *
 623 gdk_pixbuf_loader_get_pixbuf (GdkPixbufLoader *loader)
 624 {
 625         GdkPixbufLoaderPrivate *priv;
 626
 627         g_return_val_if_fail (loader != NULL, NULL);
 628         g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL);
 629
 630         priv = loader->priv;
 631
 632         if (priv->animation)
 633                 return gdk_pixbuf_animation_get_static_image (priv->animation);
 634         else
 635                 return NULL;
 636 }
 637
 638 /**
 639  * gdk_pixbuf_loader_get_animation:
 640  * @loader: A pixbuf loader
 641  *
 642  * Queries the #GdkPixbufAnimation that a pixbuf loader is currently creating.
 643  * In general it only makes sense to call this function after the "area_prepared"
 644  * signal has been emitted by the loader. If the loader doesn't have enough
 645  * bytes yet (hasn't emitted the "area_prepared" signal) this function will
 646  * return %NULL.
 647  *
 648  * Return value: The #GdkPixbufAnimation that the loader is loading, or %NULL if
 649  not enough data has been read to determine the information.
 650 **/
 651 GdkPixbufAnimation *
 652 gdk_pixbuf_loader_get_animation (GdkPixbufLoader *loader)
 653 {
 654         GdkPixbufLoaderPrivate *priv;
 655
 656         g_return_val_if_fail (loader != NULL, NULL);
 657         g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL);
 658
 659         priv = loader->priv;
 660
 661         return priv->animation;
 662 }
 663
 664 /**
 665  * gdk_pixbuf_loader_close:
 666  * @loader: A pixbuf loader.
 667  * @error: return location for a #GError, or %NULL to ignore errors
 668  *
 669  * Informs a pixbuf loader that no further writes with
 670  * gdk_pixbuf_loader_write() will occur, so that it can free its
 671  * internal loading structures. Also, tries to parse any data that
 672  * hasn't yet been parsed; if the remaining data is partial or
 673  * corrupt, an error will be returned.  If %FALSE is returned, @error
 674  * will be set to an error from the #GDK_PIXBUF_ERROR or #G_FILE_ERROR
 675  * domains. If you're just cancelling a load rather than expecting it
 676  * to be finished, passing %NULL for @error to ignore it is
 677  * reasonable.
 678  *
 679  * Returns: %TRUE if all image data written so far was successfully
 680             passed out via the update_area signal
 681  **/
 682 gboolean
 683 gdk_pixbuf_loader_close (GdkPixbufLoader *loader,
 684                          GError         **error)
 685 {
 686         GdkPixbufLoaderPrivate *priv;
 687         gboolean retval = TRUE;
 688
 689         g_return_val_if_fail (loader != NULL, TRUE);
 690         g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), TRUE);
 691         g_return_val_if_fail (error == NULL || *error == NULL, TRUE);
 692
 693         priv = loader->priv;
 694
 695         if (priv->closed)
 696                 return TRUE;
 697
 698         /* We have less the LOADER_HEADER_SIZE bytes in the image.
 699          * Flush it, and keep going.
 700          */
 701         if (priv->image_module == NULL)
 702                 {
 703                         GError *tmp = NULL;
 704                         gdk_pixbuf_loader_load_module (loader, NULL, &tmp);
 705                         if (tmp != NULL)
 706                                 {
 707                                         g_propagate_error (error, tmp);
 708                                         retval = FALSE;
 709                                 }
 710                 }
 711
 712         if (priv->image_module && priv->image_module->stop_load && priv->context)
 713                 {
 714                         if (!priv->image_module->stop_load (priv->context, error))
 715                                 {
 716                                         gdk_pixbuf_loader_ensure_error (loader, error);
 717                                         retval = FALSE;
 718                                 }
 719                 }
 720
 721         priv->closed = TRUE;
 722         if (priv->image_module && priv->holds_threadlock) {
 723                 _gdk_pixbuf_unlock (priv->image_module);
 724                 priv->holds_threadlock = FALSE;
 725         }
 726
 727         if (priv->needs_scale)
 728                 {
 729                         GdkPixbuf *tmp, *pixbuf;
 730
 731                         tmp = gdk_pixbuf_animation_get_static_image (priv->animation);
 732                         g_object_ref (tmp);
 733                         pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, tmp->has_alpha, 8, priv->width, priv->height);
 734                         g_object_unref (priv->animation);
 735                         priv->animation = gdk_pixbuf_non_anim_new (pixbuf);
 736                         g_object_unref (pixbuf);
 737                         g_signal_emit (loader, pixbuf_loader_signals[AREA_PREPARED], 0);
 738                         gdk_pixbuf_scale (tmp, pixbuf, 0, 0, priv->width, priv->height, 0, 0,
 739                                           (double) priv->width / tmp->width,
 740                                           (double) priv->height / tmp->height,
 741                                           GDK_INTERP_BILINEAR);
 742                         g_object_unref (tmp);
 743
 744                         g_signal_emit (loader, pixbuf_loader_signals[AREA_UPDATED], 0,
 745                                        0, 0, priv->width, priv->height);
 746                 }
 747
 748
 749         g_signal_emit (loader, pixbuf_loader_signals[CLOSED], 0);
 750
 751         return retval;
 752 }
 753
 754 /**
 755  * gdk_pixbuf_loader_get_format:
 756  * @loader: A pixbuf loader.
 757  *
 758  * Obtains the available information about the format of the
 759  * currently loading image file.
 760  *
 761  * Returns: A #GdkPixbufFormat or %NULL. The return value is owned
 762  * by GdkPixbuf and should not be freed.
 763  *
 764  * Since: 2.2
 765  */
 766 GdkPixbufFormat *
 767 gdk_pixbuf_loader_get_format (GdkPixbufLoader *loader)
 768 {
 769         GdkPixbufLoaderPrivate *priv;
 770
 771         g_return_val_if_fail (loader != NULL, NULL);
 772         g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL);
 773
 774         priv = loader->priv;
 775
 776         if (priv->image_module)
 777                 return _gdk_pixbuf_get_format (priv->image_module);
 778         else
 779                 return NULL;
 780 }
 781
 782
 783 #define __GDK_PIXBUF_LOADER_C__
 784 #include "gdk-pixbuf-aliasdef.c"
 785