/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */ /* GdkPixbuf library - Main header file * * 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 Library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library 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 #include "gdk-pixbuf-loader.h" #include "gdk-pixbuf-io.h" enum { AREA_UPDATED, AREA_PREPARED, CLOSED, LAST_SIGNAL }; static GtkObjectClass *parent_class; static void gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *klass); static void gdk_pixbuf_loader_init (GdkPixbufLoader *loader); static void gdk_pixbuf_loader_destroy (GtkObject *loader); static void gdk_pixbuf_loader_finalize (GtkObject *loader); static guint pixbuf_loader_signals[LAST_SIGNAL] = { 0 }; /* Internal data */ #define LOADER_HEADER_SIZE 128 typedef struct { GdkPixbuf *pixbuf; gboolean closed; gchar header_buf[LOADER_HEADER_SIZE]; gint header_buf_offset; GdkPixbufModule *image_module; gpointer context; } GdkPixbufLoaderPrivate; /* our marshaller */ typedef void (* GtkSignal_NONE__INT_INT_INT_INT) (GtkObject *object, gint arg1, gint arg2, gint arg3, gint arg4, gpointer user_data); static void gtk_marshal_NONE__INT_INT_INT_INT (GtkObject *object, GtkSignalFunc func, gpointer func_data, GtkArg * args) { GtkSignal_NONE__INT_INT_INT_INT rfunc; rfunc = (GtkSignal_NONE__INT_INT_INT_INT) func; (*rfunc) (object, GTK_VALUE_INT (args[0]), GTK_VALUE_INT (args[1]), GTK_VALUE_INT (args[2]), GTK_VALUE_INT (args[3]), func_data); } /** * 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. **/ GtkType gdk_pixbuf_loader_get_type (void) { static GtkType loader_type = 0; if (!loader_type) { static const GtkTypeInfo loader_info = { "GdkPixbufLoader", sizeof (GdkPixbufLoader), sizeof (GdkPixbufLoaderClass), (GtkClassInitFunc) gdk_pixbuf_loader_class_init, (GtkObjectInitFunc) gdk_pixbuf_loader_init, /* reserved_1 */ NULL, /* reserved_2 */ NULL, (GtkClassInitFunc) NULL, }; loader_type = gtk_type_unique (GTK_TYPE_OBJECT, &loader_info); } return loader_type; } static void gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *class) { GtkObjectClass *object_class; object_class = (GtkObjectClass *) class; parent_class = gtk_type_class (gtk_object_get_type ()); pixbuf_loader_signals[AREA_PREPARED] = gtk_signal_new ("area_prepared", GTK_RUN_LAST, parent_class->type, GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, area_prepared), gtk_marshal_NONE__NONE, GTK_TYPE_NONE, 0); pixbuf_loader_signals[AREA_UPDATED] = gtk_signal_new ("area_updated", GTK_RUN_LAST, parent_class->type, GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, area_updated), gtk_marshal_NONE__INT_INT_INT_INT, GTK_TYPE_NONE, 4, GTK_TYPE_INT, GTK_TYPE_INT, GTK_TYPE_INT, GTK_TYPE_INT); pixbuf_loader_signals[CLOSED] = gtk_signal_new ("closed", GTK_RUN_LAST, parent_class->type, GTK_SIGNAL_OFFSET (GdkPixbufLoaderClass, closed), gtk_marshal_NONE__NONE, GTK_TYPE_NONE, 0); gtk_object_class_add_signals (object_class, pixbuf_loader_signals, LAST_SIGNAL); object_class->destroy = gdk_pixbuf_loader_destroy; object_class->finalize = gdk_pixbuf_loader_finalize; } static void gdk_pixbuf_loader_init (GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv; priv = g_new0 (GdkPixbufLoaderPrivate, 1); loader->private = priv; } static void gdk_pixbuf_loader_destroy (GtkObject *object) { GdkPixbufLoader *loader; GdkPixbufLoaderPrivate *priv = NULL; g_return_if_fail (object != NULL); g_return_if_fail (GDK_IS_PIXBUF_LOADER (object)); loader = GDK_PIXBUF_LOADER (object); priv = loader->private; if (!priv->closed) gdk_pixbuf_loader_close (loader); if (priv->pixbuf) gdk_pixbuf_unref (priv->pixbuf); if (GTK_OBJECT_CLASS (parent_class)->destroy) (* GTK_OBJECT_CLASS (parent_class)->destroy) (object); } static void gdk_pixbuf_loader_finalize (GtkObject *object) { GdkPixbufLoader *loader; GdkPixbufLoaderPrivate *priv = NULL; loader = GDK_PIXBUF_LOADER (object); priv = loader->private; g_free (priv); if (GTK_OBJECT_CLASS (parent_class)->finalize) (* GTK_OBJECT_CLASS (parent_class)->finalize) (object); } static void gdk_pixbuf_loader_prepare (GdkPixbuf *pixbuf, gpointer loader) { GdkPixbufLoaderPrivate *priv = NULL; priv = GDK_PIXBUF_LOADER (loader)->private; gdk_pixbuf_ref (pixbuf); g_assert (priv->pixbuf == NULL); priv->pixbuf = pixbuf; gtk_signal_emit (GTK_OBJECT (loader), pixbuf_loader_signals[AREA_PREPARED]); } static void gdk_pixbuf_loader_update (GdkPixbuf *pixbuf, gpointer loader, guint x, guint y, guint width, guint height) { GdkPixbufLoaderPrivate *priv = NULL; priv = GDK_PIXBUF_LOADER (loader)->private; gtk_signal_emit (GTK_OBJECT (loader), pixbuf_loader_signals[AREA_UPDATED], 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))); } /** * gdk_pixbuf_loader_new: * @void: * * Creates a new pixbuf loader object. * * Return value: A newly-created pixbuf loader. **/ GdkPixbufLoader * gdk_pixbuf_loader_new (void) { return gtk_type_new (gdk_pixbuf_loader_get_type ()); } static int gdk_pixbuf_loader_load_module(GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv = loader->private; priv->image_module = gdk_pixbuf_get_module (priv->header_buf, priv->header_buf_offset); if (priv->image_module == NULL) return 0; if (priv->image_module->module == NULL) gdk_pixbuf_load_module (priv->image_module); 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_warning ("module %s does not support incremental loading.\n", priv->image_module->module_name); return 0; } priv->context = (*priv->image_module->begin_load) (gdk_pixbuf_loader_prepare, gdk_pixbuf_loader_update, loader); if (priv->context == NULL) { g_warning("Failed to begin progressive load"); return 0; } if( (* priv->image_module->load_increment) (priv->context, priv->header_buf, priv->header_buf_offset) ) return priv->header_buf_offset; return 0; } static int gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, const gchar *buf, size_t count) { int nbytes; GdkPixbufLoaderPrivate *priv = loader->private; nbytes = MIN(LOADER_HEADER_SIZE - priv->header_buf_offset, count); memcpy (priv->header_buf + priv->header_buf_offset, buf, nbytes); priv->header_buf_offset += nbytes; if(priv->header_buf_offset >= LOADER_HEADER_SIZE) gdk_pixbuf_loader_load_module(loader); return nbytes; } /** * gdk_pixbuf_loader_write: * @loader: A pixbuf loader. * @buf: Pointer to image data. * @count: Length of the @buf buffer in bytes. * * 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. * * 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 gchar *buf, size_t count) { 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->private; /* we expect it's not to be closed */ g_return_val_if_fail (priv->closed == FALSE, FALSE); if (priv->image_module == NULL) { int eaten; eaten = gdk_pixbuf_loader_eat_header_write(loader, buf, count); if (eaten <= 0) return FALSE; count -= eaten; buf += eaten; } if (count > 0 && priv->image_module->load_increment) return (* priv->image_module->load_increment) (priv->context, buf, count); return TRUE; } /** * 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. * * 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->private; return priv->pixbuf; } /** * gdk_pixbuf_loader_close: * @loader: A pixbuf loader. * * Informs a pixbuf loader that no further writes with gdk_pixbuf_load_write() * will occur, so that it can free its internal loading structures. **/ void gdk_pixbuf_loader_close (GdkPixbufLoader *loader) { GdkPixbufLoaderPrivate *priv; g_return_if_fail (loader != NULL); g_return_if_fail (GDK_IS_PIXBUF_LOADER (loader)); priv = loader->private; /* we expect it's not closed */ g_return_if_fail (priv->closed == FALSE); /* 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); if (priv->image_module && priv->image_module->stop_load) (* priv->image_module->stop_load) (priv->context); priv->closed = TRUE; gtk_signal_emit (GTK_OBJECT (loader), pixbuf_loader_signals[CLOSED]); }