What's wrong with my C code?

[ericshliao]

I have a small program (not really executable, just for experiement):

#include <glib.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
//#include <glib/gi18n-lib.h>
#include <string.h>
#include <libdjvu/ddjvuapi.h>

typedef struct _DjvuDocument DjvuDocument;

typedef struct _EvRenderContext EvRenderContext;

struct _DjvuDocument {
	GObject           parent_instance;

	ddjvu_context_t  *d_context;
	ddjvu_document_t *d_document;
	ddjvu_format_t   *d_format;
	ddjvu_format_t   *thumbs_format;

	gchar            *uri;

        /* PS exporter */
        gchar		 *ps_filename;
        GString 	 *opts;
};

struct _EvRenderContext
{
	GObject parent;
	
	//EvPage *page;
	gint    rotation;
	gdouble scale;
};

cairo_surface_t *djvu_document_render (DjvuDocument *djvu_document, int page_index)
{
	
	EvRenderContext *rc;
	
	cairo_surface_t *surface;
	gchar *pixels;
	gint   rowstride;
    ddjvu_rect_t rrect;
	ddjvu_rect_t prect;
	ddjvu_page_t *d_page;
	ddjvu_page_rotation_t rotation;
	double page_width, page_height, tmp;
	static const cairo_user_data_key_t key;

	d_page = ddjvu_page_create_by_pageno (djvu_document->d_document, page_index);
	
	while (!ddjvu_page_decoding_done (d_page))
		djvu_handle_events(djvu_document, TRUE, NULL);

	page_width = ddjvu_page_get_width (d_page) * rc->scale * SCALE_FACTOR + 0.5;
	page_height = ddjvu_page_get_height (d_page) * rc->scale * SCALE_FACTOR + 0.5;
	
	switch (rc->rotation) {
	        case 90:
			rotation = DDJVU_ROTATE_90;
			tmp = page_height;
			page_height = page_width;
			page_width = tmp;
			
			break;
	        case 180:
			rotation = DDJVU_ROTATE_180;
			
			break;
	        case 270:
			rotation = DDJVU_ROTATE_270;
			tmp = page_height;
			page_height = page_width;
			page_width = tmp;
			
			break;
	        default:
			rotation = DDJVU_ROTATE_0;
	}
///#ifdef HAVE_CAIRO_FORMAT_STRIDE_FOR_WIDTH
	rowstride = cairo_format_stride_for_width (CAIRO_FORMAT_RGB24, page_width);
//#else
//	rowstride = page_width * 4;
//#endif
	pixels = (gchar *) g_malloc (page_height * rowstride);
	surface = cairo_image_surface_create_for_data ((guchar *)pixels,
						       CAIRO_FORMAT_RGB24,
						       page_width,
						       page_height,
						       rowstride);
	cairo_surface_set_user_data (surface, &key,
				     pixels, (cairo_destroy_func_t)g_free);
	prect.x = 0;
	prect.y = 0;
	prect.w = page_width;
	prect.h = page_height;
	rrect = prect;

	ddjvu_page_set_rotation (d_page, rotation);
	
	ddjvu_page_render (d_page, DDJVU_RENDER_COLOR,
			   &prect,
			   &rrect,
			   djvu_document->d_format,
			   rowstride,
			   pixels);

	return surface;
}

/*
static void
djvu_document_finalize (GObject *object)
{
	DjvuDocument *djvu_document = DJVU_DOCUMENT (object);

	if (djvu_document->d_document)
	    ddjvu_document_release (djvu_document->d_document);
	    
	if (djvu_document->opts)
	    g_string_free (djvu_document->opts, TRUE);

	if (djvu_document->ps_filename)
	    g_free (djvu_document->ps_filename);
	    
	ddjvu_context_release (djvu_document->d_context);
	ddjvu_format_release (djvu_document->d_format);
	ddjvu_format_release (djvu_document->thumbs_format);
	g_free (djvu_document->uri);
	
	G_OBJECT_CLASS (djvu_document_parent_class)->finalize (object);
}*/


int main()
{

    return 0;
}

I compiled it with:
gcc -o test lua-djview.c `pkg-config gtk+-2.0 ddjvuapi --libs --cflags`
using GCC4.1.2 in Debian 5.

And I alwasy got error message:
lua-djview.c:35: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘*’ token

Line 35 is marked in red.

The code is copied from source code of Evince with some modification. I know it must be a silly problem, but I just can't figure it out. Please help. Thanx.

[ericshliao]

Sorry. Please ignore this problem. I found that the above code is not correct. Some variables undefinded, required headers not include...It's all my fault.

Added:
I am trying to create a djvu module for lua, so that I can create a djvu reader for iLiad using GTK+, instead of QTGui. It should save ram and loading time.

Evince uses Cairo to convert page image gererated from Djvulibre API to cairo_surface_t, then draw it on GdkWindow. That's really a clever way.