io-wbmp.c 9.02 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
/* 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>
Tor Lillqvist's avatar
Tor Lillqvist committed
33
#ifdef HAVE_UNISTD_H
34
#include <unistd.h>
Tor Lillqvist's avatar
Tor Lillqvist committed
35
#endif
36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
#include <string.h>
#include "gdk-pixbuf-private.h"
#include "gdk-pixbuf-io.h"



/* Progressive loading */

struct wbmp_progressive_state {
  ModulePreparedNotifyFunc prepared_func;
  ModuleUpdatedNotifyFunc updated_func;
  gpointer user_data;

  gboolean need_type : 1;
  gboolean need_header : 1;
  gboolean need_width : 1;
  gboolean need_height : 1;
  gboolean needmore : 1;
  gboolean 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" */
};

65
static gpointer
66 67 68 69
gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
				  ModuleUpdatedNotifyFunc updated_func,
				  ModuleFrameDoneNotifyFunc frame_done_func,
				  ModuleAnimationDoneNotifyFunc
Havoc Pennington's avatar
Havoc Pennington committed
70 71
				  anim_done_func, gpointer user_data,
                                  GError **error);
72

73 74 75 76 77
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);
78 79 80 81


/* Shared library entry point --> This should be removed when
   generic_image_load enters gdk-pixbuf-io. */
82
static GdkPixbuf *gdk_pixbuf__wbmp_image_load(FILE * f, GError **error)
83 84 85
{
	size_t length;
	char membuf[4096];
86
	struct wbmp_progressive_state *State;
87 88 89

	GdkPixbuf *pb;

Havoc Pennington's avatar
Havoc Pennington committed
90 91
	State = gdk_pixbuf__wbmp_image_begin_load(NULL, NULL, NULL, NULL, NULL,
                                                  error);
92

Havoc Pennington's avatar
Havoc Pennington committed
93 94 95
        if (State == NULL)
          return NULL;
        
96 97 98 99 100
	while (feof(f) == 0) {
		length = fread(membuf, 1, 4096, f);
		if (length > 0)
		  gdk_pixbuf__wbmp_image_load_increment(State,
							membuf,
Havoc Pennington's avatar
Havoc Pennington committed
101 102
							length,
                                                        error);
103 104 105 106 107 108 109

	}
	if (State->pixbuf != NULL)
		gdk_pixbuf_ref(State->pixbuf);

	pb = State->pixbuf;

110
	gdk_pixbuf__wbmp_image_stop_load(State, NULL);
111 112 113 114 115 116 117 118 119
	return pb;
}

/* 
 * func - called when we have pixmap created (but no image data)
 * user_data - passed as arg 1 to func
 * return context (opaque to user)
 */

120
static gpointer
121
gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
Havoc Pennington's avatar
Havoc Pennington committed
122 123 124 125 126
                                  ModuleUpdatedNotifyFunc updated_func,
                                  ModuleFrameDoneNotifyFunc frame_done_func,
                                  ModuleAnimationDoneNotifyFunc
                                  anim_done_func, gpointer user_data,
                                  GError **error)
127
{
128
	struct wbmp_progressive_state *context;
129

130
	context = g_new0(struct wbmp_progressive_state, 1);
131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
	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
 */
147 148
static gboolean gdk_pixbuf__wbmp_image_stop_load(gpointer data,
                                                 GError **error)
149
{
150 151
	struct wbmp_progressive_state *context =
	    (struct wbmp_progressive_state *) data;
152

153 154 155 156 157
        /* FIXME this thing needs to report errors if
         * we have unused image data
         */
        
	g_return_val_if_fail(context != NULL, TRUE);
158 159 160 161
	if (context->pixbuf)
	  gdk_pixbuf_unref(context->pixbuf);

	g_free(context);
162 163

        return TRUE;
164 165 166
}

static gboolean
167
getin(struct wbmp_progressive_state *context, guchar **buf, guint *buf_size, guchar *ptr, int datum_size)
168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184
{
  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;
185 186

  return TRUE;
187 188 189
}

static gboolean
190
save_rest(struct wbmp_progressive_state *context, const guchar *buf, guint buf_size)
191 192 193 194 195 196 197 198 199 200 201
{
  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
202
get_mbi(struct wbmp_progressive_state *context, guchar **buf, guint *buf_size, int *val)
203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219
{
  guchar intbuf[16];
  int i, n;
  gboolean rv;

  *val = 0;
  n = i = 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:
220
  if(!rv || (intbuf[n-1] & 0x80))
221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
    {
      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
 */
239 240 241
static gboolean gdk_pixbuf__wbmp_image_load_increment(gpointer data,
                                                      const guchar * buf,
                                                      guint size, GError **error)
242
{
243 244
	struct wbmp_progressive_state *context =
	    (struct wbmp_progressive_state *) data;
Elliot Lee's avatar
Elliot Lee committed
245
	gboolean bv = FALSE;
246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284

	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;
	      }
	    else if(context->need_height)
	      {
		bv = get_mbi(context, &buf, &size, &context->height);
		if(bv)
		  {
		    context->need_height = FALSE;
		    context->pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8, context->width, context->height);
285 286
		    g_assert(context->pixbuf);

287 288 289 290 291 292 293 294 295 296
		    if(context->prepared_func)
		      context->prepared_func(context->pixbuf, context->user_data);
		  }
	      }
	    else if(context->needmore)
	      {
		int first_row;
		first_row = context->cury;
		for( ; context->cury < context->height; context->cury++, context->curx = 0)
		  {
297
		    for( ; context->curx < context->width; context->curx += 8)
298 299 300 301 302 303 304 305 306
		      {
			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;
307
			for(xoff = 7; xoff >= 0; xoff--, ptr += 3)
308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335
			  {
			    guchar pixval;

			    if(byte & (1<<xoff))
			      pixval = 0xFF;
			    else
			      pixval = 0x0;

			    ptr[0] = ptr[1] = ptr[2] = pixval;
			  }
		      }
		  }
		context->needmore = FALSE;

	      out:
		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)
	  return save_rest(context, buf, size);
	else
	  return context->needmore;
}
336 337 338 339 340 341 342 343 344

void
gdk_pixbuf__wbmp_fill_vtable (GdkPixbufModule *module)
{
  module->load = gdk_pixbuf__wbmp_image_load;
  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;
}