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., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <config.h>
  23
  24 #include <errno.h>
  25 #include <X11/Xlib.h>
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <unistd.h>
  29 #include <fcntl.h>
  30 #include <sys/stat.h>
  31 #include <string.h>
  32 #include <time.h>
  33 #include <assert.h>
  34
  35 #ifdef USE_PNG
  36 #include <png.h>
  37 #endif
  38
  39 #include "wraster.h"
  40
  41 #define RETRY( x )      do {                            \
  42                                 x;                      \
  43                         } while (errno == EINTR);
  44
  45 typedef struct RCachedImage {
  46         RImage *image;
  47         char *file;
  48         time_t last_modif;      /* last time file was modified */
  49         time_t last_use;        /* last time image was used */
  50 } RCachedImage;
  51
  52 /*
  53  * Size of image cache
  54  */
  55 static int RImageCacheSize = -1;
  56
  57 /*
  58  * Max. size of image to store in cache
  59  */
  60 static int RImageCacheMaxImage = -1;    /* 0 = any size */
  61
  62 #define IMAGE_CACHE_SIZE        8
  63
  64 #define IMAGE_CACHE_MAX_IMAGE   64*64
  65
  66 static RCachedImage *RImageCache;
  67
  68 #define IM_ERROR        -1
  69 #define IM_UNKNOWN      0
  70 #define IM_XPM          1
  71 #define IM_TIFF         2
  72 #define IM_PNG          3
  73 #define IM_PPM          4
  74 #define IM_JPEG         5
  75 #define IM_GIF          6
  76 /* How many image types do we have. */
  77 /* Increase this when adding new image types! */
  78 #define IM_TYPES        6
  79
  80 static int identFile(char *path);
  81
  82 extern RImage *RLoadPPM(char *file_name);
  83
  84 extern RImage *RLoadXPM(RContext * context, char *file);
  85
  86 #ifdef USE_TIFF
  87 extern RImage *RLoadTIFF(char *file, int index);
  88 #endif
  89 #ifdef USE_PNG
  90 extern RImage *RLoadPNG(RContext * context, char *file);
  91 #endif
  92 #ifdef USE_JPEG
  93 extern RImage *RLoadJPEG(RContext * context, char *file_name);
  94 #endif
  95 #ifdef USE_GIF
  96 extern RImage *RLoadGIF(char *file_name, int index);
  97 #endif
  98
  99 char **RSupportedFileFormats(void)
 100 {
 101         static char *tmp[IM_TYPES + 1];
 102         int i = 0;
 103
 104         /* built-in */
 105         tmp[i++] = "XPM";
 106         /* built-in */
 107         tmp[i++] = "PPM";
 108 #ifdef USE_TIFF
 109         tmp[i++] = "TIFF";
 110 #endif
 111 #ifdef USE_PNG
 112         tmp[i++] = "PNG";
 113 #endif
 114 #ifdef USE_JPEG
 115         tmp[i++] = "JPEG";
 116 #endif
 117 #ifdef USE_GIF
 118         tmp[i++] = "GIF";
 119 #endif
 120         tmp[i] = NULL;
 121
 122         return tmp;
 123 }
 124
 125 static void init_cache()
 126 {
 127         char *tmp;
 128
 129         tmp = getenv("RIMAGE_CACHE");
 130         if (!tmp || sscanf(tmp, "%i", &RImageCacheSize) != 1) {
 131                 RImageCacheSize = IMAGE_CACHE_SIZE;
 132         }
 133         if (RImageCacheSize < 0)
 134                 RImageCacheSize = 0;
 135
 136         tmp = getenv("RIMAGE_CACHE_SIZE");
 137         if (!tmp || sscanf(tmp, "%i", &RImageCacheMaxImage) != 1) {
 138                 RImageCacheMaxImage = IMAGE_CACHE_MAX_IMAGE;
 139         }
 140
 141         if (RImageCacheSize > 0) {
 142                 RImageCache = malloc(sizeof(RCachedImage) * RImageCacheSize);
 143                 if (RImageCache == NULL) {
 144                         printf("wrlib: out of memory for image cache\n");
 145                         return;
 146                 }
 147                 memset(RImageCache, 0, sizeof(RCachedImage) * RImageCacheSize);
 148         }
 149 }
 150
 151 RImage *RLoadImage(RContext * context, char *file, int index)
 152 {
 153         RImage *image = NULL;
 154         int i;
 155         struct stat st;
 156
 157         assert(file != NULL);
 158
 159         if (RImageCacheSize < 0) {
 160                 init_cache();
 161         }
 162
 163         if (RImageCacheSize > 0) {
 164
 165                 for (i = 0; i < RImageCacheSize; i++) {
 166                         if (RImageCache[i].file && strcmp(file, RImageCache[i].file) == 0) {
 167
 168                                 if (stat(file, &st) == 0 && st.st_mtime == RImageCache[i].last_modif) {
 169                                         RImageCache[i].last_use = time(NULL);
 170
 171                                         return RCloneImage(RImageCache[i].image);
 172
 173                                 } else {
 174                                         free(RImageCache[i].file);
 175                                         RImageCache[i].file = NULL;
 176                                         RReleaseImage(RImageCache[i].image);
 177                                 }
 178                         }
 179                 }
 180         }
 181
 182         switch (identFile(file)) {
 183         case IM_ERROR:
 184                 return NULL;
 185
 186         case IM_UNKNOWN:
 187                 RErrorCode = RERR_BADFORMAT;
 188                 return NULL;
 189
 190         case IM_XPM:
 191                 image = RLoadXPM(context, file);
 192                 break;
 193
 194 #ifdef USE_TIFF
 195         case IM_TIFF:
 196                 image = RLoadTIFF(file, index);
 197                 break;
 198 #endif                          /* USE_TIFF */
 199
 200 #ifdef USE_PNG
 201         case IM_PNG:
 202                 image = RLoadPNG(context, file);
 203                 break;
 204 #endif                          /* USE_PNG */
 205
 206 #ifdef USE_JPEG
 207         case IM_JPEG:
 208                 image = RLoadJPEG(context, file);
 209                 break;
 210 #endif                          /* USE_JPEG */
 211
 212 #ifdef USE_GIF
 213         case IM_GIF:
 214                 image = RLoadGIF(file, index);
 215                 break;
 216 #endif                          /* USE_GIF */
 217
 218         case IM_PPM:
 219                 image = RLoadPPM(file);
 220                 break;
 221
 222         default:
 223                 RErrorCode = RERR_BADFORMAT;
 224                 return NULL;
 225         }
 226
 227         /* store image in cache */
 228         if (RImageCacheSize > 0 && image &&
 229             (RImageCacheMaxImage == 0 || RImageCacheMaxImage >= image->width * image->height)) {
 230                 time_t oldest = time(NULL);
 231                 int oldest_idx = 0;
 232                 int done = 0;
 233
 234                 for (i = 0; i < RImageCacheSize; i++) {
 235                         if (!RImageCache[i].file) {
 236                                 RImageCache[i].file = malloc(strlen(file) + 1);
 237                                 strcpy(RImageCache[i].file, file);
 238                                 RImageCache[i].image = RCloneImage(image);
 239                                 RImageCache[i].last_modif = st.st_mtime;
 240                                 RImageCache[i].last_use = time(NULL);
 241                                 done = 1;
 242                                 break;
 243                         } else {
 244                                 if (oldest > RImageCache[i].last_use) {
 245                                         oldest = RImageCache[i].last_use;
 246                                         oldest_idx = i;
 247                                 }
 248                         }
 249                 }
 250
 251                 /* if no slot available, dump least recently used one */
 252                 if (!done) {
 253                         free(RImageCache[oldest_idx].file);
 254                         RReleaseImage(RImageCache[oldest_idx].image);
 255                         RImageCache[oldest_idx].file = malloc(strlen(file) + 1);
 256                         strcpy(RImageCache[oldest_idx].file, file);
 257                         RImageCache[oldest_idx].image = RCloneImage(image);
 258                         RImageCache[oldest_idx].last_modif = st.st_mtime;
 259                         RImageCache[oldest_idx].last_use = time(NULL);
 260                 }
 261         }
 262
 263         return image;
 264 }
 265
 266 char *RGetImageFileFormat(char *file)
 267 {
 268         switch (identFile(file)) {
 269         case IM_XPM:
 270                 return "XPM";
 271
 272 #ifdef USE_TIFF
 273         case IM_TIFF:
 274                 return "TIFF";
 275 #endif                          /* USE_TIFF */
 276
 277 #ifdef USE_PNG
 278         case IM_PNG:
 279                 return "PNG";
 280 #endif                          /* USE_PNG */
 281
 282 #ifdef USE_JPEG
 283         case IM_JPEG:
 284                 return "JPEG";
 285 #endif                          /* USE_JPEG */
 286
 287 #ifdef USE_GIF
 288         case IM_GIF:
 289                 return "GIF";
 290 #endif                          /* USE_GIF */
 291
 292         case IM_PPM:
 293                 return "PPM";
 294
 295         default:
 296                 return NULL;
 297         }
 298 }
 299
 300 static int identFile(char *path)
 301 {
 302         FILE *file;
 303         unsigned char buffer[32];
 304         size_t nread;
 305
 306         assert(path != NULL);
 307
 308         RETRY( file = fopen(path, "rb") )
 309         if (file == NULL) {
 310                 RErrorCode = RERR_OPEN;
 311                 return IM_ERROR;
 312         }
 313
 314         RETRY( nread = fread(buffer, 1, sizeof(buffer), file) )
 315         if (nread < sizeof(buffer) || ferror(file)) {
 316                 RETRY( fclose(file) )
 317                 RErrorCode = RERR_READ;
 318                 return IM_ERROR;
 319         }
 320         RETRY( fclose(file) )
 321
 322         /* check for XPM */
 323         if (strncmp((char *)buffer, "/* XPM */", 9) == 0)
 324                 return IM_XPM;
 325
 326         /* check for TIFF */
 327         if ((buffer[0] == 'I' && buffer[1] == 'I' && buffer[2] == '*' && buffer[3] == 0)
 328             || (buffer[0] == 'M' && buffer[1] == 'M' && buffer[2] == 0 && buffer[3] == '*'))
 329                 return IM_TIFF;
 330
 331 #ifdef USE_PNG
 332         /* check for PNG */
 333         if (!png_sig_cmp(buffer, 0, 8))
 334                 return IM_PNG;
 335 #endif
 336
 337         /* check for raw PPM or PGM */
 338         if (buffer[0] == 'P' && (buffer[1] == '5' || buffer[1] == '6'))
 339                 return IM_PPM;
 340
 341         /* check for JPEG */
 342         if (buffer[0] == 0xff && buffer[1] == 0xd8)
 343                 return IM_JPEG;
 344
 345         /* check for GIF */
 346         if (buffer[0] == 'G' && buffer[1] == 'I' && buffer[2] == 'F')
 347                 return IM_GIF;
 348
 349         return IM_UNKNOWN;
 350 }