gtk/gdk-pixbuf/io-wbmp.c
Matthias Clasen 365e7efc35 Use better magic. (#339877, Bastien Nocera)
2007-10-16  Matthias Clasen  <mclasen@redhat.com>

        * io-wbmp.c: Use better magic.  (#339877, Bastien Nocera)



svn path=/trunk/; revision=18915
2007-10-16 18:42:04 +00:00

383 lines
9.7 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* -*- mode: C; c-file-style: "linux" -*- */
/* GdkPixbuf library - Wireless Bitmap image loader
*
* Copyright (C) 2000 Red Hat, Inc.
*
* Authors: Elliot Lee <sopwith@redhat.com
*
* Based on io-bmp.c
*
* 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.
*/
/*
Known bugs:
* Since this is based off the libgd implementation, no extended headers implemented (not required for a WAP client)
*/
#include <config.h>
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <string.h>
#include "gdk-pixbuf-private.h"
#include "gdk-pixbuf-io.h"
/* Progressive loading */
struct wbmp_progressive_state {
GdkPixbufModulePreparedFunc prepared_func;
GdkPixbufModuleUpdatedFunc updated_func;
gpointer user_data;
guint need_type : 1;
guint need_header : 1;
guint need_width : 1;
guint need_height : 1;
guint needmore : 1;
guint call_progressive_updates : 1;
guchar last_buf[16]; /* Just needs to be big enough to hold the largest datum requestable via 'getin' */
guint last_len;
int type;
int width, height, curx, cury;
GdkPixbuf *pixbuf; /* Our "target" */
};
static gpointer
gdk_pixbuf__wbmp_image_begin_load(GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error);
static gboolean gdk_pixbuf__wbmp_image_stop_load(gpointer data, GError **error);
static gboolean gdk_pixbuf__wbmp_image_load_increment(gpointer data,
const guchar * buf,
guint size,
GError **error);
/*
* func - called when we have pixmap created (but no image data)
* user_data - passed as arg 1 to func
* return context (opaque to user)
*/
static gpointer
gdk_pixbuf__wbmp_image_begin_load(GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error)
{
struct wbmp_progressive_state *context;
context = g_new0(struct wbmp_progressive_state, 1);
context->prepared_func = prepared_func;
context->updated_func = updated_func;
context->user_data = user_data;
context->needmore = context->need_type = context->need_header = context->need_width = context->need_height = TRUE;
context->call_progressive_updates = TRUE;
context->pixbuf = NULL;
return (gpointer) context;
}
/*
* context - returned from image_begin_load
*
* free context, unref gdk_pixbuf
*/
static gboolean gdk_pixbuf__wbmp_image_stop_load(gpointer data,
GError **error)
{
struct wbmp_progressive_state *context =
(struct wbmp_progressive_state *) data;
/* FIXME this thing needs to report errors if
* we have unused image data
*/
g_return_val_if_fail(context != NULL, TRUE);
if (context->pixbuf)
g_object_unref(context->pixbuf);
g_free(context);
return TRUE;
}
static gboolean
getin(struct wbmp_progressive_state *context, const guchar **buf, guint *buf_size, guchar *ptr, int datum_size)
{
int last_num, buf_num;
if((context->last_len + *buf_size) < datum_size)
return FALSE;
/* We know we can pull it out of there */
last_num = MIN(datum_size, context->last_len);
buf_num = MIN(datum_size-last_num, *buf_size);
memcpy(ptr, context->last_buf, last_num);
memcpy(ptr+last_num, *buf, buf_num);
context->last_len -= last_num;
if(context->last_len)
memmove(context->last_buf, context->last_buf+last_num, context->last_len);
*buf_size -= buf_num;
*buf += buf_num;
return TRUE;
}
static gboolean
save_rest(struct wbmp_progressive_state *context, const guchar *buf, guint buf_size)
{
if(buf_size > (sizeof(context->last_buf) - context->last_len))
return FALSE;
memcpy(context->last_buf+context->last_len, buf, buf_size);
context->last_len += buf_size;
return TRUE;
}
static gboolean
get_mbi(struct wbmp_progressive_state *context, const guchar **buf, guint *buf_size, int *val)
{
guchar intbuf[16];
int n;
gboolean rv;
*val = 0;
n = 0;
do {
rv = getin(context, buf, buf_size, intbuf+n, 1);
if(!rv)
goto out;
*val <<= 7;
*val |= intbuf[n] & 0x7F;
n++;
} while(n < sizeof(intbuf) && (intbuf[n-1] & 0x80));
out:
if(!rv || (intbuf[n-1] & 0x80))
{
rv = save_rest(context, intbuf, n);
if(!rv)
g_error("Couldn't save_rest of intbuf");
return FALSE;
}
return TRUE;
}
/*
* context - from image_begin_load
* buf - new image data
* size - length of new image data
*
* append image data onto inrecrementally built output image
*/
static gboolean gdk_pixbuf__wbmp_image_load_increment(gpointer data,
const guchar * buf,
guint size, GError **error)
{
struct wbmp_progressive_state *context =
(struct wbmp_progressive_state *) data;
gboolean bv = FALSE;
do
{
if(context->need_type)
{
guchar val;
bv = getin(context, &buf, &size, &val, 1);
if(bv)
{
context->type = val;
context->need_type = FALSE;
}
}
else if(context->need_header)
{
guchar val;
bv = getin(context, &buf, &size, &val, 1);
if(bv)
{
/* We skip over the extended header - val is unused */
if(!(val & 0x80))
context->need_header = FALSE;
}
}
else if(context->need_width)
{
bv = get_mbi(context, &buf, &size, &context->width);
if(bv) {
context->need_width = FALSE;
if (context->width <= 0) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Image has zero width"));
return FALSE;
}
}
}
else if(context->need_height)
{
bv = get_mbi(context, &buf, &size, &context->height);
if(bv)
{
context->need_height = FALSE;
if (context->height <= 0) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Image has zero height"));
return FALSE;
}
context->pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8, context->width, context->height);
if (!context->pixbuf) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Not enough memory to load image"));
return FALSE;
}
if(context->prepared_func)
context->prepared_func(context->pixbuf, NULL, context->user_data);
}
}
else if(context->needmore)
{
int first_row;
first_row = context->cury;
for( ; context->cury < context->height; context->cury++, context->curx = 0)
{
for( ; context->curx < context->width; context->curx += 8)
{
guchar byte;
guchar *ptr;
int xoff;
bv = getin(context, &buf, &size, &byte, 1);
if(!bv)
goto out;
ptr = context->pixbuf->pixels + context->pixbuf->rowstride * context->cury + context->curx * 3;
for(xoff = 7; xoff >= 0; xoff--, ptr += 3)
{
guchar pixval;
if (context->curx + (7 - xoff) == context->width)
break;
if(byte & (1<<xoff))
pixval = 0xFF;
else
pixval = 0x0;
ptr[0] = ptr[1] = ptr[2] = pixval;
}
}
}
context->needmore = FALSE;
out:
if(context->updated_func)
context->updated_func(context->pixbuf, 0, first_row, context->width, context->cury - first_row + 1,
context->user_data);
}
else
bv = FALSE; /* Nothing left to do, stop feeding me data! */
} while(bv);
if(size) {
bv = save_rest(context, buf, size);
if (!bv) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Couldn't save the rest"));
return FALSE;
}
}
return TRUE;
}
#ifndef INCLUDE_wbmp
#define MODULE_ENTRY(type,function) function
#else
#define MODULE_ENTRY(type,function) _gdk_pixbuf__ ## type ## _ ## function
#endif
void
MODULE_ENTRY (wbmp, fill_vtable) (GdkPixbufModule *module)
{
module->begin_load = gdk_pixbuf__wbmp_image_begin_load;
module->stop_load = gdk_pixbuf__wbmp_image_stop_load;
module->load_increment = gdk_pixbuf__wbmp_image_load_increment;
}
void
MODULE_ENTRY (wbmp, fill_info) (GdkPixbufFormat *info)
{
static GdkPixbufModulePattern signature[] = {
{ " ", "zz", 1 },
{ " \140", "z ", 1 },
{ " \100", "z ", 1 },
{ " \040", "z ", 1 },
{ NULL, NULL, 0 }
};
static gchar * mime_types[] = {
"image/vnd.wap.wbmp",
NULL
};
static gchar * extensions[] = {
"wbmp",
NULL
};
info->name = "wbmp";
info->signature = signature;
info->description = N_("The WBMP image format");
info->mime_types = mime_types;
info->extensions = extensions;
info->flags = GDK_PIXBUF_FORMAT_THREADSAFE;
info->license = "LGPL";
}