io-wbmp.c 7.74 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 33 34 35 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 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80
/* 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>
#include <unistd.h>
#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" */
};

gpointer
gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
				  ModuleUpdatedNotifyFunc updated_func,
				  ModuleFrameDoneNotifyFunc frame_done_func,
				  ModuleAnimationDoneNotifyFunc
				  anim_done_func, gpointer user_data);

void gdk_pixbuf__wbmp_image_stop_load(gpointer data);
gboolean gdk_pixbuf__wbmp_image_load_increment(gpointer data, guchar * buf,
					       guint size);


/* Shared library entry point --> This should be removed when
   generic_image_load enters gdk-pixbuf-io. */
GdkPixbuf *gdk_pixbuf__wbmp_image_load(FILE * f)
{
	size_t length;
	char membuf[4096];
81
	struct wbmp_progressive_state *State;
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99

	GdkPixbuf *pb;

	State = gdk_pixbuf__wbmp_image_begin_load(NULL, NULL, NULL, NULL, NULL);

	while (feof(f) == 0) {
		length = fread(membuf, 1, 4096, f);
		if (length > 0)
		  gdk_pixbuf__wbmp_image_load_increment(State,
							membuf,
							length);

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

	pb = State->pixbuf;

100
	gdk_pixbuf__wbmp_image_stop_load(State);
101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116
	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)
 */

gpointer
gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
				 ModuleUpdatedNotifyFunc updated_func,
				 ModuleFrameDoneNotifyFunc frame_done_func,
				 ModuleAnimationDoneNotifyFunc
				 anim_done_func, gpointer user_data)
{
117
	struct wbmp_progressive_state *context;
118

119
	context = g_new0(struct wbmp_progressive_state, 1);
120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137
	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
 */
void gdk_pixbuf__wbmp_image_stop_load(gpointer data)
{
138 139
	struct wbmp_progressive_state *context =
	    (struct wbmp_progressive_state *) data;
140 141 142 143 144 145 146 147 148

	g_return_if_fail(context != NULL);
	if (context->pixbuf)
	  gdk_pixbuf_unref(context->pixbuf);

	g_free(context);
}

static gboolean
149
getin(struct wbmp_progressive_state *context, guchar **buf, guint *buf_size, guchar *ptr, int datum_size)
150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
{
  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;
167 168

  return TRUE;
169 170 171
}

static gboolean
172
save_rest(struct wbmp_progressive_state *context, const guchar *buf, guint buf_size)
173 174 175 176 177 178 179 180 181 182 183
{
  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
184
get_mbi(struct wbmp_progressive_state *context, guchar **buf, guint *buf_size, int *val)
185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201
{
  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:
202
  if(!rv || (intbuf[n-1] & 0x80))
203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220
    {
      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
 */
Elliot Lee's avatar
Elliot Lee committed
221
gboolean gdk_pixbuf__wbmp_image_load_increment(gpointer data, guchar * buf,
222 223
					      guint size)
{
224 225
	struct wbmp_progressive_state *context =
	    (struct wbmp_progressive_state *) data;
226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265
	gboolean bv;

	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);
266 267
		    g_assert(context->pixbuf);

268 269 270 271 272 273 274 275 276 277
		    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)
		  {
278
		    for( ; context->curx < context->width; context->curx += 8)
279 280 281 282 283 284 285 286 287
		      {
			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;
288
			for(xoff = 7; xoff >= 0; xoff--, ptr += 3)
289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316
			  {
			    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;
}