workbench/libs/png/contrib/pngminus/png2pnm.c

   1 /*
   2  *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file
   3  *  copyright (C) 1999,2017 by Willem van Schaik <willem at schaik.com>
   4  *
   5  *  version 1.0 - 1999.10.15 - First version.
   6  *          1.1 - 2017.04.22 - Add buffer-size check (Glenn Randers-Pehrson)
   7  *          1.2 - 2017.08.24 - Fix potential overflow in buffer-size check
   8  *                             (Glenn Randers-Pehrson)
   9  *          1.3 - 2017.08.28 - Add PNGMINUS_UNUSED (Christian Hesse)
  10  *
  11  *  Permission to use, copy, modify, and distribute this software and
  12  *  its documentation for any purpose and without fee is hereby granted,
  13  *  provided that the above copyright notice appear in all copies and
  14  *  that both that copyright notice and this permission notice appear in
  15  *  supporting documentation. This software is provided "as is" without
  16  *  express or implied warranty.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #ifdef __TURBOC__
  22 #include <mem.h>
  23 #include <fcntl.h>
  24 #endif
  25 #include <zlib.h>
  26
  27 #ifndef BOOL
  28 #define BOOL unsigned char
  29 #endif
  30 #ifndef TRUE
  31 #define TRUE (BOOL) 1
  32 #endif
  33 #ifndef FALSE
  34 #define FALSE (BOOL) 0
  35 #endif
  36
  37 #ifdef __TURBOC__
  38 #define STDIN  0
  39 #define STDOUT 1
  40 #define STDERR 2
  41 #endif
  42
  43 /* to make png2pnm verbose so we can find problems (needs to be before png.h) */
  44 #ifndef PNG_DEBUG
  45 #define PNG_DEBUG 0
  46 #endif
  47
  48
  49 #include "png.h"
  50
  51 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
  52 #ifndef png_jmpbuf
  53 #  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
  54 #endif
  55
  56 #ifndef PNGMINUS_UNUSED
  57 /* Unused formal parameter warnings are silenced using the following macro
  58  * which is expected to have no bad effects on performance (optimizing
  59  * compilers will probably remove it entirely).
  60  */
  61 #  define PNGMINUS_UNUSED(param) (void)param
  62 #endif
  63
  64 /* function prototypes */
  65
  66 int  main (int argc, char *argv[]);
  67 void usage ();
  68 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw,
  69    BOOL alpha);
  70
  71 /*
  72  *  main
  73  */
  74
  75 int main(int argc, char *argv[])
  76 {
  77   FILE *fp_rd = stdin;
  78   FILE *fp_wr = stdout;
  79   FILE *fp_al = NULL;
  80   BOOL raw = TRUE;
  81   BOOL alpha = FALSE;
  82   int argi;
  83
  84   for (argi = 1; argi < argc; argi++)
  85   {
  86     if (argv[argi][0] == '-')
  87     {
  88       switch (argv[argi][1])
  89       {
  90         case 'n':
  91           raw = FALSE;
  92           break;
  93         case 'r':
  94           raw = TRUE;
  95           break;
  96         case 'a':
  97           alpha = TRUE;
  98           argi++;
  99           if ((fp_al = fopen (argv[argi], "wb")) == NULL)
 100           {
 101             fprintf (stderr, "PNM2PNG\n");
 102             fprintf (stderr, "Error:  can not create alpha-channel file %s\n",
 103                argv[argi]);
 104             exit (1);
 105           }
 106           break;
 107         case 'h':
 108         case '?':
 109           usage();
 110           exit(0);
 111           break;
 112         default:
 113           fprintf (stderr, "PNG2PNM\n");
 114           fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
 115           usage();
 116           exit(1);
 117           break;
 118       } /* end switch */
 119     }
 120     else if (fp_rd == stdin)
 121     {
 122       if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
 123       {
 124              fprintf (stderr, "PNG2PNM\n");
 125             fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
 126             exit (1);
 127       }
 128     }
 129     else if (fp_wr == stdout)
 130     {
 131       if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
 132       {
 133         fprintf (stderr, "PNG2PNM\n");
 134         fprintf (stderr, "Error:  can not create file %s\n", argv[argi]);
 135         exit (1);
 136       }
 137     }
 138     else
 139     {
 140       fprintf (stderr, "PNG2PNM\n");
 141       fprintf (stderr, "Error:  too many parameters\n");
 142       usage();
 143       exit(1);
 144     }
 145   } /* end for */
 146
 147 #ifdef __TURBOC__
 148   /* set stdin/stdout if required to binary */
 149   if (fp_rd == stdin)
 150   {
 151     setmode (STDIN, O_BINARY);
 152   }
 153   if ((raw) && (fp_wr == stdout))
 154   {
 155     setmode (STDOUT, O_BINARY);
 156   }
 157 #endif
 158
 159   /* call the conversion program itself */
 160   if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
 161   {
 162     fprintf (stderr, "PNG2PNM\n");
 163     fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");
 164     exit(1);
 165   }
 166
 167   /* close input file */
 168   fclose (fp_rd);
 169   /* close output file */
 170   fclose (fp_wr);
 171   /* close alpha file */
 172   if (alpha)
 173     fclose (fp_al);
 174
 175   return 0;
 176 }
 177
 178 /*
 179  *  usage
 180  */
 181
 182 void usage()
 183 {
 184   fprintf (stderr, "PNG2PNM\n");
 185   fprintf (stderr, "   by Willem van Schaik, 1999\n");
 186 #ifdef __TURBOC__
 187   fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
 188 #else
 189   fprintf (stderr, "   for Linux (and Unix) compilers\n");
 190 #endif
 191   fprintf (stderr, "Usage:  png2pnm [options] <file>.png [<file>.pnm]\n");
 192   fprintf (stderr, "   or:  ... | png2pnm [options]\n");
 193   fprintf (stderr, "Options:\n");
 194   fprintf (stderr,
 195      "   -r[aw]   write pnm-file in binary format (P4/P5/P6) (default)\n");
 196   fprintf (stderr, "   -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");
 197   fprintf (stderr,
 198      "   -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
 199   fprintf (stderr, "   -h | -?  print this help-information\n");
 200 }
 201
 202 /*
 203  *  png2pnm
 204  */
 205
 206 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
 207     volatile BOOL raw, BOOL alpha)
 208 {
 209   png_struct    *png_ptr = NULL;
 210   png_info        *info_ptr = NULL;
 211   png_byte      buf[8];
 212   png_byte      *png_pixels = NULL;
 213   png_byte      **row_pointers = NULL;
 214   png_byte      *pix_ptr = NULL;
 215   png_uint_32   row_bytes;
 216
 217   png_uint_32   width;
 218   png_uint_32   height;
 219   int           bit_depth;
 220   int           channels;
 221   int           color_type;
 222   int           alpha_present;
 223   int           row, col;
 224   int           ret;
 225   int           i;
 226   long          dep_16;
 227
 228   /* read and check signature in PNG file */
 229   ret = fread (buf, 1, 8, png_file);
 230   if (ret != 8)
 231     return FALSE;
 232
 233   ret = png_sig_cmp (buf, 0, 8);
 234   if (ret)
 235     return FALSE;
 236
 237   /* create png and info structures */
 238
 239   png_ptr = png_create_read_struct (png_get_libpng_ver(NULL),
 240     NULL, NULL, NULL);
 241   if (!png_ptr)
 242     return FALSE;   /* out of memory */
 243
 244   info_ptr = png_create_info_struct (png_ptr);
 245   if (!info_ptr)
 246   {
 247     png_destroy_read_struct (&png_ptr, NULL, NULL);
 248     return FALSE;   /* out of memory */
 249   }
 250
 251   if (setjmp (png_jmpbuf(png_ptr)))
 252   {
 253     png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
 254     return FALSE;
 255   }
 256
 257   /* set up the input control for C streams */
 258   png_init_io (png_ptr, png_file);
 259   png_set_sig_bytes (png_ptr, 8);  /* we already read the 8 signature bytes */
 260
 261   /* read the file information */
 262   png_read_info (png_ptr, info_ptr);
 263
 264   /* get size and bit-depth of the PNG-image */
 265   png_get_IHDR (png_ptr, info_ptr,
 266     &width, &height, &bit_depth, &color_type,
 267     NULL, NULL, NULL);
 268
 269   /* set-up the transformations */
 270
 271   /* transform paletted images into full-color rgb */
 272   if (color_type == PNG_COLOR_TYPE_PALETTE)
 273     png_set_expand (png_ptr);
 274   /* expand images to bit-depth 8 (only applicable for grayscale images) */
 275   if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
 276     png_set_expand (png_ptr);
 277   /* transform transparency maps into full alpha-channel */
 278   if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
 279     png_set_expand (png_ptr);
 280
 281 #ifdef NJET
 282   /* downgrade 16-bit images to 8-bit */
 283   if (bit_depth == 16)
 284     png_set_strip_16 (png_ptr);
 285   /* transform grayscale images into full-color */
 286   if (color_type == PNG_COLOR_TYPE_GRAY ||
 287     color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
 288     png_set_gray_to_rgb (png_ptr);
 289   /* only if file has a file gamma, we do a correction */
 290   if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
 291     png_set_gamma (png_ptr, (double) 2.2, file_gamma);
 292 #endif
 293
 294   /* all transformations have been registered; now update info_ptr data,
 295    * get rowbytes and channels, and allocate image memory */
 296
 297   png_read_update_info (png_ptr, info_ptr);
 298
 299   /* get the new color-type and bit-depth (after expansion/stripping) */
 300   png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
 301     NULL, NULL, NULL);
 302
 303   /* check for 16-bit files */
 304   if (bit_depth == 16)
 305   {
 306     raw = FALSE;
 307 #ifdef __TURBOC__
 308     pnm_file->flags &= ~((unsigned) _F_BIN);
 309 #endif
 310   }
 311
 312   /* calculate new number of channels and store alpha-presence */
 313   if (color_type == PNG_COLOR_TYPE_GRAY)
 314     channels = 1;
 315   else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
 316     channels = 2;
 317   else if (color_type == PNG_COLOR_TYPE_RGB)
 318     channels = 3;
 319   else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
 320     channels = 4;
 321   else
 322     channels = 0; /* should never happen */
 323   alpha_present = (channels - 1) % 2;
 324
 325   /* check if alpha is expected to be present in file */
 326   if (alpha && !alpha_present)
 327   {
 328     fprintf (stderr, "PNG2PNM\n");
 329     fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");
 330     exit (1);
 331   }
 332
 333   /* row_bytes is the width x number of channels x (bit-depth / 8) */
 334   row_bytes = png_get_rowbytes (png_ptr, info_ptr);
 335
 336   if ((row_bytes == 0 || (size_t)height > ((size_t)(-1))/(size_t)row_bytes))
 337   {
 338     /* too big */
 339     png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
 340     return FALSE;
 341   }
 342   if ((png_pixels = (png_byte *)
 343      malloc ((size_t)row_bytes * (size_t)height * sizeof (png_byte))) == NULL)
 344   {
 345     png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
 346     return FALSE;
 347   }
 348
 349   if ((row_pointers = (png_byte **)
 350      malloc ((size_t)height * sizeof (png_bytep))) == NULL)
 351   {
 352     png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
 353     free (png_pixels);
 354     png_pixels = NULL;
 355     return FALSE;
 356   }
 357
 358   /* set the individual row_pointers to point at the correct offsets */
 359   for (i = 0; i < ((int) height); i++)
 360     row_pointers[i] = png_pixels + i * row_bytes;
 361
 362   /* now we can go ahead and just read the whole image */
 363   png_read_image (png_ptr, row_pointers);
 364
 365   /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
 366   png_read_end (png_ptr, info_ptr);
 367
 368   /* clean up after the read, and free any memory allocated - REQUIRED */
 369   png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);
 370
 371   /* write header of PNM file */
 372
 373   if ((color_type == PNG_COLOR_TYPE_GRAY) ||
 374       (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
 375   {
 376     fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");
 377     fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
 378     fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
 379   }
 380   else if ((color_type == PNG_COLOR_TYPE_RGB) ||
 381            (color_type == PNG_COLOR_TYPE_RGB_ALPHA))
 382   {
 383     fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");
 384     fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
 385     fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
 386   }
 387
 388   /* write header of PGM file with alpha channel */
 389
 390   if ((alpha) &&
 391       ((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) ||
 392        (color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
 393   {
 394     fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");
 395     fprintf (alpha_file, "%d %d\n", (int) width, (int) height);
 396     fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
 397   }
 398
 399   /* write data to PNM file */
 400   pix_ptr = png_pixels;
 401
 402   for (row = 0; row < (int) height; row++)
 403   {
 404     for (col = 0; col < (int) width; col++)
 405     {
 406       for (i = 0; i < (channels - alpha_present); i++)
 407       {
 408         if (raw)
 409           fputc ((int) *pix_ptr++ , pnm_file);
 410         else
 411           if (bit_depth == 16){
 412             dep_16 = (long) *pix_ptr++;
 413             fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));
 414           }
 415           else
 416             fprintf (pnm_file, "%ld ", (long) *pix_ptr++);
 417       }
 418       if (alpha_present)
 419       {
 420         if (!alpha)
 421         {
 422           pix_ptr++; /* alpha */
 423           if (bit_depth == 16)
 424             pix_ptr++;
 425         }
 426         else /* output alpha-channel as pgm file */
 427         {
 428           if (raw)
 429             fputc ((int) *pix_ptr++ , alpha_file);
 430           else
 431             if (bit_depth == 16)
 432             {
 433               dep_16 = (long) *pix_ptr++;
 434               fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
 435             }
 436             else
 437               fprintf (alpha_file, "%ld ", (long) *pix_ptr++);
 438         }
 439       } /* if alpha_present */
 440
 441       if (!raw)
 442         if (col % 4 == 3)
 443           fprintf (pnm_file, "\n");
 444     } /* end for col */
 445
 446     if (!raw)
 447       if (col % 4 != 0)
 448         fprintf (pnm_file, "\n");
 449   } /* end for row */
 450
 451   if (row_pointers != (unsigned char**) NULL)
 452     free (row_pointers);
 453   if (png_pixels != (unsigned char*) NULL)
 454     free (png_pixels);
 455
 456   PNGMINUS_UNUSED(raw); /* to quiet a Coverity defect */
 457   return TRUE;
 458
 459 } /* end of source */
 460