Loading framework done, start of PNG loader

2 files changed, 212 insertions, 20 deletions

diff --git a/gdk-pixbuf/gdk-pixbuf-io.c b/gdk-pixbuf/gdk-pixbuf-io.c
index 61786ded2..03422587b 100644
--- a/gdk-pixbuf/gdk-pixbuf-io.c
+++ b/gdk-pixbuf/gdk-pixbuf-io.c
@@ -5,22 +5,124 @@
  *    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)(char *buffer, int size);
-	GdkPixBuf *(*load)(char *filename);
+	gboolean   (*format_check)(unsigned char *buffer, int size);
+	GModule   *module;
+	GdkPixBuf *(*load)(FILE *f)
 	int        (*save)(char *filename, ...);
-} loaders [] = {
-	{ "png",  pixbuf_check_png,  NULL, NULL },
-	{ "jpeg", pixbuf_check_jpeg, NULL, NULL },
-	{ "tiff", pixbuf_check_tiff, NULL, NULL },
-	{ "gif",  pixbuf_check_gif,  NULL, NULL },
-	{ "xpm",  pixbuf_check_xpm,  pixbuf_xpm_load, pixbuf_xpm_save },
-	{ "bmp",  pixbuf_check_bmp,  NULL, NULL },
-	{ "ppm",  pixbuf_check_ppm,  NULL, NULL },
-	{ NULL, NULL, NULL, NULL },
+} 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
@@ -33,8 +135,27 @@ image_file_format (const char *file)
 }
 
 static void
-image_loader_load (int idx)
+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 *
@@ -49,21 +170,30 @@ gdk_pixbuf_load_image (const char *file)
 	if (!f)
 		return NULL;
 	n = fread (&buffer, 1, sizeof (buffer), f);
-	fclose (f);
-	if (n == 0)
+
+	if (n == 0){
+		fclose (f);		
 		return NULL;
+	}
 
-	for (i = 0; loaders [i].module_name; i++){
-		if ((*loaders [i].format_check)(buffer, n)){
-			if (!loaders [i].load)
-				image_loader_load (i);
+	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 (!loaders [i].load)
+			if (!file_formats [i].load){
+				fclose (f);
 				return NULL;
+			}
 
-			return (*loaders [i].load)(file);
+			rewind (f);
+			pixbuf = (*file_formats [i].load)(f);
+			fclose (f);
+			return pixbuf;
 		}
 	}
 
+	fclose (f);
 	return NULL;
 }
+
diff --git a/gdk-pixbuf/io-png.c b/gdk-pixbuf/io-png.c
new file mode 100644
index 000000000..18f661ce0
--- /dev/null
+++ b/gdk-pixbuf/io-png.c
@@ -0,0 +1,62 @@
+/*
+ * io-png.c: GdkPixBuf image loader for PNG files.
+ *
+ * Author:
+ *    Rasterman (raster@redhat.com).
+ *    Miguel de Icaza (miguel@gnu.org)
+ *
+ */
+#include <config.h>
+#include <stdio.h>
+#include "gdk-pixbuf.h"
+#include "gdk-pixbuf-io.h"
+#include <png.h>
+
+/* Shared library entry point */
+GdkPixBuf *
+image_load (FILE *f);
+{
+	png_structp png;
+	png_infop   info_ptr, end_info;
+	int width, height, depth, color_type, interlace_type;
+	
+	g_return_val_if_fail (filename != NULL, NULL);
+
+	png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+	if (png)
+		return NULL;
+
+	info_ptr = png_create_info_struct (png);
+	if (!info_ptr){
+		png_destroy_read_struct (&png, NULL, NULL);
+		return NULL;
+	}
+
+	end_info = png_create_info_struct (png);
+	if (!end_info){
+		png_destroy_read_struct (&png, &info_ptr, NULL);
+		return NULL:
+	}
+
+	if (setjmp (png->jmpbuf)){
+		png_destroy_read_struct (&png, &info_ptr, &end_info);
+		return NULL;
+	}
+
+	png_init_io (pngptr, f);
+
+	png_read_info (png, info_ptr);
+	png_get_IHDR (png, info_ptr, &width, &height, &depth, &color_type, &interlace_type, NULL, NULL);
+
+	if (color_type == color_type == PNG_COLOR_TYPE_PALETTE)
+		png_set_expand (png);
+	
+	png_set_strip_16 (png);
+	png_set_packing (png);
+	if (png_get_valid (png, info_ptr, PNG_INFO_tRNS))
+		png_set_expand (png);
+
+	png_set_filler (png, 0xff, PNG_FILLER_AFTER);
+
+	/* FIXME finish this */
+}