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/*
* gdk-pixbuf-io.c: Code to load images into GdkPixBufs
*
* Author:
* Miguel de Icaza (miguel@gnu.org)
*/
#include <config.h>
#include <stdio.h>
#include "gdk-pixbuf.h"
static gboolean
pixbuf_check_png (unsigned char *buffer, int size)
{
if (size < 28)
return FALSE;
if (buffer [0] != 0x89 ||
buffer [1] != 'P' ||
buffer [2] != 'N' ||
buffer [3] != 'G' ||
buffer [4] != 0x0d ||
buffer [5] != 0x0a ||
buffer [6] != 0x1a ||
buffer [7] != 0x0a)
return FALSE;
return TRUE;
}
static gboolean
pixbuf_check_jpeg (unsigned char *buffer, int size)
{
if (size < 10)
return FALSE;
if (buffer [0] != 0xff || buffer [1] != 0xd8)
return FALSE;
return TRUE;
}
static gboolean
pixbuf_check_tiff (unsigned char *buffer, int size)
{
if (size < 10)
return FALSE;
if (buffer [0] == 'M' && buffer [1] == 'M' && buffer [2] == 0 && buffer [3] == 0x2a)
return TRUE;
if (buffer [0] == 'I' && buffer [1] == 'I' && buffer [2] == 0x2a && buffer [3] == 0)
return TRUE;
return FALSE;
}
static gboolean
pixbuf_check_gif (unsigned char *buffer, int size)
{
if (size < 20)
return FALSE;
if (strncmp (buffer, "GIF8", 4) == 0)
return TRUE;
return FALSE;
}
static gboolean
pixbuf_check_xpm (unsigned char *buffer, int size)
{
if (size < 20)
return FALSE;
if (strncmp (buffer, "/* XPM */", 9) == 0)
return TRUE;
return FALSE;
}
static gboolean
pixbuf_check_bmp (unsigned char *buffer, int size)
{
if (size < 20)
return FALSE;
if (buffer [0] != 'B' || buffer [1] != 'M')
return FALSE;
return TRUE;
}
static gboolean
pixbuf_check_ppm (unsigned char *buffer, int size)
{
if (size < 20)
return FALSE;
if (buffer [0] == 'P'){
if (buffer [1] == '1' ||
buffer [1] == '2' ||
buffer [1] == '3' ||
buffer [1] == '4' ||
buffer [1] == '5' ||
buffer [1] == '6')
return TRUE;
}
return FALSE;
}
static struct {
char *module_name;
gboolean (*format_check)(unsigned char *buffer, int size);
GModule *module;
GdkPixBuf *(*load)(FILE *f)
int (*save)(char *filename, ...);
} file_formats [] = {
{ "png", pixbuf_check_png, NULL, NULL, NULL },
{ "jpeg", pixbuf_check_jpeg, NULL, NULL, NULL },
{ "tiff", pixbuf_check_tiff, NULL, NULL, NULL },
{ "gif", pixbuf_check_gif, NULL, NULL, NULL },
{ "xpm", pixbuf_check_xpm, NULL, NULL, NULL }
{ "bmp", pixbuf_check_bmp, NULL, NULL, NULL },
{ "ppm", pixbuf_check_ppm, NULL, NULL, NULL },
{ NULL, NULL, NULL, NULL, NULL },
};
static int
image_file_format (const char *file)
{
FILE *f = fopen (file);
if (!f)
return -1;
}
static void
image_handler_load (int idx)
{
char *module_name = g_strconcat ("pixbuf-", file_formats [idx].module_name, NULL);
char *path;
GModule *module;
void *load_sym, *save_sym;
path = g_module_build_path (PIXBUF_LIBDIR, module_name);
g_free (module_name);
module = g_module_open (path, G_MODULE_BIND_LAZY);
if (!module)
return;
file_formats [idx].module = module;
if (g_module_symbol (module, "image_load", &load_sym))
file_formats [idx].load = load_sym;
if (g_module_symbol (module, "image_save", &save_sym))
file_formats [idx].save = save_sym;
}
GdkPixBuf *
gdk_pixbuf_load_image (const char *file)
{
GdkPixBuf *pixbuf;
FormatLoader format_loader;
FILE *f;
char buffer [128];
f = fopen (file);
if (!f)
return NULL;
n = fread (&buffer, 1, sizeof (buffer), f);
if (n == 0){
fclose (f);
return NULL;
}
for (i = 0; file_formats [i].module_name; i++){
if ((*file_formats [i].format_check)(buffer, n)){
if (!file_formats [i].load)
image_handler_load (i);
if (!file_formats [i].load){
fclose (f);
return NULL;
}
rewind (f);
pixbuf = (*file_formats [i].load)(f);
fclose (f);
return pixbuf;
}
}
fclose (f);
return NULL;
}
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