/* GdkPixbuf library - Progressive loader object * * Copyright (C) 1999 The Free Software Foundation * * Authors: Mark Crichton * Miguel de Icaza * Federico Mena-Quintero * Jonathan Blandford * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include #include "gdk-pixbuf-private.h" #include "gdk-pixbuf-loader.h" #include "gdk-pixbuf-io.h" #include "gdk-pixbuf-marshal.h" #include enum { AREA_UPDATED, AREA_PREPARED, FRAME_DONE, ANIMATION_DONE, CLOSED, LAST_SIGNAL }; static void gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *klass); static void gdk_pixbuf_loader_init (GdkPixbufLoader *loader); static void gdk_pixbuf_loader_finalize (GObject *loader); static gpointer parent_class = NULL; static guint pixbuf_loader_signals[LAST_SIGNAL] = { 0 }; /* Internal data */ #define LOADER_HEADER_SIZE 128 typedef struct { GdkPixbuf *pixbuf; GdkPixbufAnimation *animation; gboolean closed; guchar header_buf[LOADER_HEADER_SIZE]; gint header_buf_offset; GdkPixbufModule *image_module; gpointer context; } GdkPixbufLoaderPrivate; /** * gdk_pixbuf_loader_get_type: * @void: * * Registers the #GdkPixubfLoader class if necessary, and returns the type ID * associated to it. * * Return value: The type ID of the #GdkPixbufLoader class. **/ GType gdk_pixbuf_loader_get_type (void) { static GType loader_type = 0; if (!loader_type) { static const GTypeInfo loader_info = { sizeof (GdkPixbufLoaderClass), (GBaseInitFunc) NULL, (GBaseFinalizeFunc) NULL, (GClassInitFunc) gdk_pixbuf_loader_class_init, NULL, /* class_finalize */ NULL, /* class_data */ sizeof (GdkPixbufLoader), 0, /* n_preallocs */ (GInstanceInitFunc) gdk_pixbuf_loader_init }; loader_type = g_type_register_static (G_TYPE_OBJECT, "GdkPixbufLoader", &loader_info, 0); } return loader_type; } static void gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *class) { GObjectClass *object_class; object_class = (GObjectClass *) class; parent_class = g_type_class_peek_parent (class); object_class->finalize = gdk_pixbuf_loader_finalize; pixbuf_loader_signals[AREA_PREPARED] = g_signal_newc ("area_prepared", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GdkPixbufLoaderClass, area_prepared), NULL, gdk_pixbuf_marshal_VOID__VOID, G_TYPE_NONE, 0); pixbuf_loader_signals[AREA_UPDATED] = g_signal_newc ("area_updated", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GdkPixbufLoaderClass, area_updated), NULL, gdk_pixbuf_marshal_VOID__INT_INT_INT_INT, G_TYPE_NONE, 4, G_TYPE_INT, G_TYPE_INT, G_TYPE_INT, G_TYPE_INT); pixbuf_loader_signals[FRAME_DONE] = g_signal_newc ("frame_done", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GdkPixbufLoaderClass, frame_done), NULL, gdk_pixbuf_marshal_VOID__POINTER, G_TYPE_NONE, 1, GDK_TYPE_PIXBUF_FRAME); pixbuf_loader_signals[ANIMATION_DONE] = g_signal_newc ("animation_done", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GdkPixbufLoaderClass, animation_done), NULL, gdk_pixbuf_marshal_VOID__VOID, G_TYPE_NONE, 0); pixbuf_loader_signals[CLOSED] = g_signal_newc ("closed", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GdkPixbufLoaderClass, closed), NULL, gdk_pixbuf_marshal_VOID__VOID, G_TYPE_NONE, 0); } static void gdk_pixbuf_loader_init (GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv; priv = g_new0 (GdkPixbufLoaderPrivate, 1); loader->priv = priv; } static void gdk_pixbuf_loader_finalize (GObject *object) { GdkPixbufLoader *loader; GdkPixbufLoaderPrivate *priv = NULL; loader = GDK_PIXBUF_LOADER (object); priv = loader->priv; if (!priv->closed) 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."); if (priv->animation) gdk_pixbuf_animation_unref (priv->animation); if (priv->pixbuf) gdk_pixbuf_unref (priv->pixbuf); g_free (priv); G_OBJECT_CLASS (parent_class)->finalize (object); } static void gdk_pixbuf_loader_prepare (GdkPixbuf *pixbuf, gpointer loader) { GdkPixbufLoaderPrivate *priv = NULL; priv = GDK_PIXBUF_LOADER (loader)->priv; gdk_pixbuf_ref (pixbuf); g_assert (priv->pixbuf == NULL); priv->pixbuf = pixbuf; g_signal_emit (G_OBJECT (loader), pixbuf_loader_signals[AREA_PREPARED], 0); } static void gdk_pixbuf_loader_update (GdkPixbuf *pixbuf, guint x, guint y, guint width, guint height, gpointer loader) { GdkPixbufLoaderPrivate *priv = NULL; priv = GDK_PIXBUF_LOADER (loader)->priv; g_signal_emit (G_OBJECT (loader), pixbuf_loader_signals[AREA_UPDATED], 0, x, y, /* sanity check in here. Defend against an errant loader */ MIN (width, gdk_pixbuf_get_width (priv->pixbuf)), MIN (height, gdk_pixbuf_get_height (priv->pixbuf))); } static void gdk_pixbuf_loader_frame_done (GdkPixbufFrame *frame, gpointer loader) { GdkPixbufLoaderPrivate *priv = NULL; priv = GDK_PIXBUF_LOADER (loader)->priv; priv->pixbuf = NULL; if (priv->animation == NULL) { priv->animation = g_object_new (GDK_TYPE_PIXBUF_ANIMATION, NULL); priv->animation->n_frames = 0; priv->animation->width = gdk_pixbuf_get_width (frame->pixbuf) + frame->x_offset; priv->animation->height = gdk_pixbuf_get_height (frame->pixbuf) + frame->y_offset; } else { int w, h; /* update bbox size */ w = gdk_pixbuf_get_width (frame->pixbuf) + frame->x_offset; h = gdk_pixbuf_get_height (frame->pixbuf) + frame->y_offset; if (w > priv->animation->width) { priv->animation->width = w; } if (h > priv->animation->height) { priv->animation->height = h; } } priv->animation->frames = g_list_append (priv->animation->frames, frame); priv->animation->n_frames++; g_signal_emit (G_OBJECT (loader), pixbuf_loader_signals[FRAME_DONE], 0, frame); } static void gdk_pixbuf_loader_animation_done (GdkPixbuf *pixbuf, gpointer loader) { GdkPixbufLoaderPrivate *priv = NULL; GdkPixbufFrame *frame; GList *current = NULL; gint h, w; priv = GDK_PIXBUF_LOADER (loader)->priv; priv->pixbuf = NULL; current = gdk_pixbuf_animation_get_frames (priv->animation); while (current) { frame = (GdkPixbufFrame *) current->data; /* update bbox size */ w = gdk_pixbuf_get_width (frame->pixbuf) + frame->x_offset; h = gdk_pixbuf_get_height (frame->pixbuf) + frame->y_offset; if (w > priv->animation->width) priv->animation->width = w; if (h > priv->animation->height) priv->animation->height = h; current = current->next; } g_signal_emit (G_OBJECT (loader), pixbuf_loader_signals[ANIMATION_DONE], 0); } static gint gdk_pixbuf_loader_load_module (GdkPixbufLoader *loader, const char *image_type, GError **error) { GdkPixbufLoaderPrivate *priv = loader->priv; if (image_type) { priv->image_module = gdk_pixbuf_get_named_module (image_type, error); } else { g_return_val_if_fail (priv->header_buf_offset > 0, 0); priv->image_module = gdk_pixbuf_get_module (priv->header_buf, priv->header_buf_offset, NULL, error); } if (priv->image_module == NULL) return 0; if (priv->image_module->module == NULL) if (!gdk_pixbuf_load_module (priv->image_module, error)) return 0; if (priv->image_module->module == NULL) return 0; if ((priv->image_module->begin_load == NULL) || (priv->image_module->stop_load == NULL) || (priv->image_module->load_increment == NULL)) { g_set_error (error, GDK_PIXBUF_ERROR, GDK_PIXBUF_ERROR_UNSUPPORTED_OPERATION, _("Incremental loading of image type '%s' is not supported"), image_type); return 0; } priv->context = priv->image_module->begin_load (gdk_pixbuf_loader_prepare, gdk_pixbuf_loader_update, gdk_pixbuf_loader_frame_done, gdk_pixbuf_loader_animation_done, loader, error); if (priv->context == NULL) { /* Defense against broken loaders; DO NOT take this as a GError * example */ if (error && *error == NULL) { g_warning ("Bug! loader '%s' didn't set an error on failure", priv->image_module->module_name); g_set_error (error, GDK_PIXBUF_ERROR, GDK_PIXBUF_ERROR_FAILED, _("Internal error: Image loader module '%s'" " failed to begin loading an image, but didn't" " give a reason for the failure"), priv->image_module->module_name); } return 0; } if (priv->header_buf_offset && priv->image_module->load_increment (priv->context, priv->header_buf, priv->header_buf_offset, error)) return priv->header_buf_offset; return 0; } static int gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, const guchar *buf, gsize count, GError **error) { gint n_bytes; GdkPixbufLoaderPrivate *priv = loader->priv; n_bytes = MIN(LOADER_HEADER_SIZE - priv->header_buf_offset, count); memcpy (priv->header_buf + priv->header_buf_offset, buf, n_bytes); priv->header_buf_offset += n_bytes; if (priv->header_buf_offset >= LOADER_HEADER_SIZE) { if (gdk_pixbuf_loader_load_module (loader, NULL, error) == 0) return 0; } return n_bytes; } /** * gdk_pixbuf_loader_write: * @loader: A pixbuf loader. * @buf: Pointer to image data. * @count: Length of the @buf buffer in bytes. * @error: return location for errors * * This will cause a pixbuf loader to parse the next @count bytes of * an image. It will return TRUE if the data was loaded successfully, * and FALSE if an error occurred. In the latter case, the loader * will be closed, and will not accept further writes. If FALSE is * returned, @error will be set to an error from the #GDK_PIXBUF_ERROR * or #G_FILE_ERROR domains. * * Return value: #TRUE if the write was successful, or #FALSE if the loader * cannot parse the buffer. **/ gboolean gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const guchar *buf, gsize count, GError **error) { GdkPixbufLoaderPrivate *priv; g_return_val_if_fail (loader != NULL, FALSE); g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), FALSE); g_return_val_if_fail (buf != NULL, FALSE); g_return_val_if_fail (count >= 0, FALSE); priv = loader->priv; /* we expect it's not to be closed */ g_return_val_if_fail (priv->closed == FALSE, FALSE); if (priv->image_module == NULL) { gint eaten; eaten = gdk_pixbuf_loader_eat_header_write(loader, buf, count, error); if (eaten <= 0) return FALSE; count -= eaten; buf += eaten; } if (count > 0 && priv->image_module->load_increment) { gboolean retval; retval = priv->image_module->load_increment (priv->context, buf, count, error); if (!retval && error && *error == NULL) { /* Fix up busted image loader */ g_warning ("Bug! loader '%s' didn't set an error on failure", priv->image_module->module_name); g_set_error (error, GDK_PIXBUF_ERROR, GDK_PIXBUF_ERROR_FAILED, _("Internal error: Image loader module '%s'" " failed to begin loading an image, but didn't" " give a reason for the failure"), priv->image_module->module_name); } return retval; } return TRUE; } /** * gdk_pixbuf_loader_new: * * Creates a new pixbuf loader object. * * Return value: A newly-created pixbuf loader. **/ GdkPixbufLoader * gdk_pixbuf_loader_new (void) { return g_object_new (GDK_TYPE_PIXBUF_LOADER, NULL); } /** * gdk_pixbuf_loader_new_with_type: * * Creates a new pixbuf loader object. * * Return value: A newly-created pixbuf loader. **/ GdkPixbufLoader * gdk_pixbuf_loader_new_with_type (const char *image_type, GError **error) { GdkPixbufLoader *retval; GError *tmp; retval = g_object_new (GDK_TYPE_PIXBUF_LOADER, NULL); tmp = NULL; gdk_pixbuf_loader_load_module(retval, image_type, &tmp); if (tmp != NULL) { g_propagate_error (error, tmp); g_object_unref (G_OBJECT (retval)); return NULL; } return retval; } /** * gdk_pixbuf_loader_get_pixbuf: * @loader: A pixbuf loader. * * Queries the GdkPixbuf that a pixbuf loader is currently creating. * In general it only makes sense to call this function afer the * "area_prepared" signal has been emitted by the loader; this means * that enough data has been read to know the size of the image that * will be allocated. If the loader has not received enough data via * gdk_pixbuf_loader_write(), then this function returns NULL. The * returned pixbuf will be the same in all future calls to the loader, * so simply calling gdk_pixbuf_ref() should be sufficient to continue * using it. Additionally, if the loader is an animation, it will * return the first frame of the animation. * * Return value: The GdkPixbuf that the loader is creating, or NULL if not * enough data has been read to determine how to create the image buffer. **/ GdkPixbuf * gdk_pixbuf_loader_get_pixbuf (GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv; g_return_val_if_fail (loader != NULL, NULL); g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL); priv = loader->priv; if (priv->animation) { GList *list; list = gdk_pixbuf_animation_get_frames (priv->animation); if (list != NULL) { GdkPixbufFrame *frame = list->data; return gdk_pixbuf_frame_get_pixbuf (frame); } } return priv->pixbuf; } /** * gdk_pixbuf_loader_get_animation: * @loader: A pixbuf loader * * Queries the GdkPixbufAnimation that a pixbuf loader is currently creating. * In general it only makes sense to call this function afer the "area_prepared" * signal has been emitted by the loader. If the image is not an animation, * then it will return NULL. * * Return value: The GdkPixbufAnimation that the loader is loading, or NULL if not enough data has been read to determine the information. **/ GdkPixbufAnimation * gdk_pixbuf_loader_get_animation (GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv; g_return_val_if_fail (loader != NULL, NULL); g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), NULL); priv = loader->priv; return priv->animation; } /** * gdk_pixbuf_loader_close: * @loader: A pixbuf loader. * @error: return location for a #GError, or %NULL to ignore errors * * Informs a pixbuf loader that no further writes with * gdk_pixbuf_loader_write() will occur, so that it can free its * internal loading structures. Also, tries to parse any data that * hasn't yet been parsed; if the remaining data is partial or * corrupt, an error will be returned. If FALSE is returned, @error * will be set to an error from the #GDK_PIXBUF_ERROR or #G_FILE_ERROR * domains. If you're just cancelling a load rather than expecting it * to be finished, passing %NULL for @error to ignore it is * reasonable. * * Returns: %TRUE if all image data written so far was successfully passed out via the update_area signal **/ gboolean gdk_pixbuf_loader_close (GdkPixbufLoader *loader, GError **error) { GdkPixbufLoaderPrivate *priv; gboolean retval = TRUE; g_return_val_if_fail (loader != NULL, TRUE); g_return_val_if_fail (GDK_IS_PIXBUF_LOADER (loader), TRUE); priv = loader->priv; /* we expect it's not closed */ g_return_val_if_fail (priv->closed == FALSE, TRUE); /* We have less the 128 bytes in the image. Flush it, and keep going. */ if (priv->image_module == NULL) gdk_pixbuf_loader_load_module (loader, NULL, NULL); if (priv->image_module && priv->image_module->stop_load) retval = priv->image_module->stop_load (priv->context, error); priv->closed = TRUE; g_signal_emit (G_OBJECT (loader), pixbuf_loader_signals[CLOSED], 0); return retval; }