wrlib/load.c

   1 /* load.c - load image from file
   2  *
   3  * Raster graphics library
   4  *
   5  * Copyright (c) 1997-2003 Alfredo K. Kojima
   6  *
   7  *  This library is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU Library General Public
   9  *  License as published by the Free Software Foundation; either
  10  *  version 2 of the License, or (at your option) any later version.
  11  *
  12  *  This library is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  *  Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU Library General Public
  18  *  License along with this library; if not, write to the Free
  19  *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  20  *  MA 02110-1301, USA.
  21  */
  22
  23 #include <config.h>
  24
  25 #include <errno.h>
  26 #include <X11/Xlib.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <unistd.h>
  30 #include <fcntl.h>
  31 #include <sys/stat.h>
  32 #include <string.h>
  33 #include <time.h>
  34 #include <assert.h>
  35
  36 #ifdef USE_PNG
  37 #include <png.h>
  38 #endif
  39
  40 #include "wraster.h"
  41 #include "imgformat.h"
  42
  43 #define RETRY( x )      do {                            \
  44                                 x;                      \
  45                         } while (errno == EINTR);
  46
  47 typedef struct RCachedImage {
  48         RImage *image;
  49         char *file;
  50         time_t last_modif;      /* last time file was modified */
  51         time_t last_use;        /* last time image was used */
  52 } RCachedImage;
  53
  54 /*
  55  * Size of image cache
  56  */
  57 static int RImageCacheSize = -1;
  58
  59 /*
  60  * Max. size of image to store in cache
  61  */
  62 static int RImageCacheMaxImage = -1;    /* 0 = any size */
  63
  64 #define IMAGE_CACHE_SIZE        8
  65
  66 #define IMAGE_CACHE_MAX_IMAGE   64*64
  67
  68 static RCachedImage *RImageCache;
  69
  70
  71 static WRImgFormat identFile(const char *path);
  72
  73
  74 char **RSupportedFileFormats(void)
  75 {
  76         static char *tmp[IM_TYPES + 1];
  77         int i = 0;
  78
  79         /* built-in */
  80         tmp[i++] = "XPM";
  81         /* built-in */
  82         tmp[i++] = "PPM";
  83 #ifdef USE_TIFF
  84         tmp[i++] = "TIFF";
  85 #endif
  86 #ifdef USE_PNG
  87         tmp[i++] = "PNG";
  88 #endif
  89 #ifdef USE_JPEG
  90         tmp[i++] = "JPEG";
  91 #endif
  92 #ifdef USE_GIF
  93         tmp[i++] = "GIF";
  94 #endif
  95         tmp[i] = NULL;
  96
  97         return tmp;
  98 }
  99
 100 static void init_cache(void)
 101 {
 102         char *tmp;
 103
 104         tmp = getenv("RIMAGE_CACHE");
 105         if (!tmp || sscanf(tmp, "%i", &RImageCacheSize) != 1) {
 106                 RImageCacheSize = IMAGE_CACHE_SIZE;
 107         }
 108         if (RImageCacheSize < 0)
 109                 RImageCacheSize = 0;
 110
 111         tmp = getenv("RIMAGE_CACHE_SIZE");
 112         if (!tmp || sscanf(tmp, "%i", &RImageCacheMaxImage) != 1) {
 113                 RImageCacheMaxImage = IMAGE_CACHE_MAX_IMAGE;
 114         }
 115
 116         if (RImageCacheSize > 0) {
 117                 RImageCache = malloc(sizeof(RCachedImage) * RImageCacheSize);
 118                 if (RImageCache == NULL) {
 119                         printf("wrlib: out of memory for image cache\n");
 120                         return;
 121                 }
 122                 memset(RImageCache, 0, sizeof(RCachedImage) * RImageCacheSize);
 123         }
 124 }
 125
 126 RImage *RLoadImage(RContext * context, const char *file, int index)
 127 {
 128         RImage *image = NULL;
 129         int i;
 130         struct stat st;
 131
 132         assert(file != NULL);
 133
 134         if (RImageCacheSize < 0) {
 135                 init_cache();
 136         }
 137
 138         if (RImageCacheSize > 0) {
 139
 140                 for (i = 0; i < RImageCacheSize; i++) {
 141                         if (RImageCache[i].file && strcmp(file, RImageCache[i].file) == 0) {
 142
 143                                 if (stat(file, &st) == 0 && st.st_mtime == RImageCache[i].last_modif) {
 144                                         RImageCache[i].last_use = time(NULL);
 145
 146                                         return RCloneImage(RImageCache[i].image);
 147
 148                                 } else {
 149                                         free(RImageCache[i].file);
 150                                         RImageCache[i].file = NULL;
 151                                         RReleaseImage(RImageCache[i].image);
 152                                 }
 153                         }
 154                 }
 155         }
 156
 157         switch (identFile(file)) {
 158         case IM_ERROR:
 159                 return NULL;
 160
 161         case IM_UNKNOWN:
 162                 RErrorCode = RERR_BADFORMAT;
 163                 return NULL;
 164
 165         case IM_XPM:
 166                 image = RLoadXPM(context, file);
 167                 break;
 168
 169 #ifdef USE_TIFF
 170         case IM_TIFF:
 171                 image = RLoadTIFF(file, index);
 172                 break;
 173 #endif                          /* USE_TIFF */
 174
 175 #ifdef USE_PNG
 176         case IM_PNG:
 177                 image = RLoadPNG(context, file);
 178                 break;
 179 #endif                          /* USE_PNG */
 180
 181 #ifdef USE_JPEG
 182         case IM_JPEG:
 183                 image = RLoadJPEG(context, file);
 184                 break;
 185 #endif                          /* USE_JPEG */
 186
 187 #ifdef USE_GIF
 188         case IM_GIF:
 189                 image = RLoadGIF(file, index);
 190                 break;
 191 #endif                          /* USE_GIF */
 192
 193         case IM_PPM:
 194                 image = RLoadPPM(file);
 195                 break;
 196
 197         default:
 198                 RErrorCode = RERR_BADFORMAT;
 199                 return NULL;
 200         }
 201
 202         /* store image in cache */
 203         if (RImageCacheSize > 0 && image &&
 204             (RImageCacheMaxImage == 0 || RImageCacheMaxImage >= image->width * image->height)) {
 205                 time_t oldest = time(NULL);
 206                 int oldest_idx = 0;
 207                 int done = 0;
 208
 209                 for (i = 0; i < RImageCacheSize; i++) {
 210                         if (!RImageCache[i].file) {
 211                                 RImageCache[i].file = malloc(strlen(file) + 1);
 212                                 strcpy(RImageCache[i].file, file);
 213                                 RImageCache[i].image = RCloneImage(image);
 214                                 RImageCache[i].last_modif = st.st_mtime;
 215                                 RImageCache[i].last_use = time(NULL);
 216                                 done = 1;
 217                                 break;
 218                         } else {
 219                                 if (oldest > RImageCache[i].last_use) {
 220                                         oldest = RImageCache[i].last_use;
 221                                         oldest_idx = i;
 222                                 }
 223                         }
 224                 }
 225
 226                 /* if no slot available, dump least recently used one */
 227                 if (!done) {
 228                         free(RImageCache[oldest_idx].file);
 229                         RReleaseImage(RImageCache[oldest_idx].image);
 230                         RImageCache[oldest_idx].file = malloc(strlen(file) + 1);
 231                         strcpy(RImageCache[oldest_idx].file, file);
 232                         RImageCache[oldest_idx].image = RCloneImage(image);
 233                         RImageCache[oldest_idx].last_modif = st.st_mtime;
 234                         RImageCache[oldest_idx].last_use = time(NULL);
 235                 }
 236         }
 237
 238         return image;
 239 }
 240
 241 char *RGetImageFileFormat(const char *file)
 242 {
 243         switch (identFile(file)) {
 244         case IM_XPM:
 245                 return "XPM";
 246
 247 #ifdef USE_TIFF
 248         case IM_TIFF:
 249                 return "TIFF";
 250 #endif                          /* USE_TIFF */
 251
 252 #ifdef USE_PNG
 253         case IM_PNG:
 254                 return "PNG";
 255 #endif                          /* USE_PNG */
 256
 257 #ifdef USE_JPEG
 258         case IM_JPEG:
 259                 return "JPEG";
 260 #endif                          /* USE_JPEG */
 261
 262 #ifdef USE_GIF
 263         case IM_GIF:
 264                 return "GIF";
 265 #endif                          /* USE_GIF */
 266
 267         case IM_PPM:
 268                 return "PPM";
 269
 270         default:
 271                 return NULL;
 272         }
 273 }
 274
 275 static WRImgFormat identFile(const char *path)
 276 {
 277         FILE *file;
 278         unsigned char buffer[32];
 279         size_t nread;
 280
 281         assert(path != NULL);
 282
 283         RETRY( file = fopen(path, "rb") )
 284         if (file == NULL) {
 285                 RErrorCode = RERR_OPEN;
 286                 return IM_ERROR;
 287         }
 288
 289         RETRY( nread = fread(buffer, 1, sizeof(buffer), file) )
 290         if (nread < sizeof(buffer) || ferror(file)) {
 291                 RETRY( fclose(file) )
 292                 RErrorCode = RERR_READ;
 293                 return IM_ERROR;
 294         }
 295         RETRY( fclose(file) )
 296
 297         /* check for XPM */
 298         if (strncmp((char *)buffer, "/* XPM */", 9) == 0)
 299                 return IM_XPM;
 300
 301         /* check for TIFF */
 302         if ((buffer[0] == 'I' && buffer[1] == 'I' && buffer[2] == '*' && buffer[3] == 0)
 303             || (buffer[0] == 'M' && buffer[1] == 'M' && buffer[2] == 0 && buffer[3] == '*'))
 304                 return IM_TIFF;
 305
 306 #ifdef USE_PNG
 307         /* check for PNG */
 308         if (!png_sig_cmp(buffer, 0, 8))
 309                 return IM_PNG;
 310 #endif
 311
 312         /* check for raw PPM or PGM */
 313         if (buffer[0] == 'P' && (buffer[1] == '5' || buffer[1] == '6'))
 314                 return IM_PPM;
 315
 316         /* check for JPEG */
 317         if (buffer[0] == 0xff && buffer[1] == 0xd8)
 318                 return IM_JPEG;
 319
 320         /* check for GIF */
 321         if (buffer[0] == 'G' && buffer[1] == 'I' && buffer[2] == 'F')
 322                 return IM_GIF;
 323
 324         return IM_UNKNOWN;
 325 }