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src/third-party/libpng/contrib/libtests/makepng.c (view raw)

   1/* makepng.c
   2 *
   3 * Copyright (c) 2013 John Cunningham Bowler
   4 *
   5 * Last changed in libpng 1.6.1 [March 28, 2013]
   6 *
   7 * This code is released under the libpng license.
   8 * For conditions of distribution and use, see the disclaimer
   9 * and license in png.h
  10 *
  11 * Make a test PNG image.  The arguments are as follows:
  12 *
  13 *  makepng [--sRGB|--linear|--1.8] [--color=<color>] color-type bit-depth \
  14 *      [file-name]
  15 *
  16 * The color-type may be numeric (and must match the numbers used by the PNG
  17 * specification) or one of the format names listed below.  The bit-depth is the
  18 * component bit depth, or the pixel bit-depth for a color-mapped image.
  19 *
  20 * Without any options no color-space information is written, with the options
  21 * an sRGB or the appropriate gAMA chunk is written.  "1.8" refers to the
  22 * display system used on older Apple computers to correct for high ambient
  23 * light levels in the viewing environment; it applies a transform of
  24 * approximately value^(1/1.45) to the color values and so a gAMA chunk of 65909
  25 * is written (1.45/2.2).
  26 *
  27 * The image data is generated internally.  Unless --color is given the images
  28 * used are as follows:
  29 *
  30 * 1 channel: a square image with a diamond, the least luminous colors are on
  31 *    the edge of the image, the most luminous in the center.
  32 *
  33 * 2 channels: the color channel increases in luminosity from top to bottom, the
  34 *    alpha channel increases in opacity from left to right.
  35 *
  36 * 3 channels: linear combinations of, from the top-left corner clockwise,
  37 *    black, green, white, red.
  38 *
  39 * 4 channels: linear combinations of, from the top-left corner clockwise,
  40 *    transparent, red, green, blue.
  41 *
  42 * For color-mapped images a four channel color-map is used and the PNG file has
  43 * a tRNS chunk, as follows:
  44 *
  45 * 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
  46 * 2-bit: entry 0: transparent-green
  47 *        entry 1: 40%-red
  48 *        entry 2: 80%-blue
  49 *        entry 3: opaque-white
  50 * 4-bit: the 16 combinations of the 2-bit case
  51 * 8-bit: the 256 combinations of the 4-bit case
  52 *
  53 * The palette always has 2^bit-depth entries and the tRNS chunk one fewer.  The
  54 * image is the 1-channel diamond, but using palette index, not luminosity.
  55 *
  56 * Image size is determined by the final pixel depth in bits, i.e. channels x
  57 * bit-depth, as follows:
  58 *
  59 * 8 bits or less:    64x64
  60 * 16 bits:           256x256
  61 * More than 16 bits: 1024x1024
  62 *
  63 * Row filtering is turned off (the 'none' filter is used on every row) and the
  64 * images are not interlaced.
  65 *
  66 * If --color is given then the whole image has that color, color-mapped images
  67 * will have exactly one palette entry and all image files with be 16x16 in
  68 * size.  The color value is 1 to 4 decimal numbers as appropriate for the color
  69 * type.
  70 *
  71 * If file-name is given then the PNG is written to that file, else it is
  72 * written to stdout.  Notice that stdout is not supported on systems where, by
  73 * default, it assumes text output; this program makes no attempt to change the
  74 * text mode of stdout!
  75 */
  76#define _ISOC99_SOURCE /* for strtoull */
  77
  78#include <stddef.h> /* for offsetof */
  79#include <stdlib.h>
  80#include <stdio.h>
  81#include <string.h>
  82#include <ctype.h>
  83#include <math.h>
  84#include <errno.h>
  85
  86#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
  87#  include <config.h>
  88#endif
  89
  90/* Define the following to use this test against your installed libpng, rather
  91 * than the one being built here:
  92 */
  93#ifdef PNG_FREESTANDING_TESTS
  94#  include <png.h>
  95#else
  96#  include "../../png.h"
  97#endif
  98
  99/* This structure is used for inserting extra chunks (the --insert argument, not
 100 * documented above.)
 101 */
 102typedef struct chunk_insert
 103{
 104   struct chunk_insert *next;
 105   void               (*insert)(png_structp, png_infop, int, png_charpp);
 106   int                  nparams;
 107   png_charp            parameters[1];
 108} chunk_insert;
 109
 110static int
 111channels_of_type(int color_type)
 112{
 113   if (color_type & PNG_COLOR_MASK_PALETTE)
 114      return 1;
 115
 116   else
 117   {
 118      int channels = 1;
 119
 120      if (color_type & PNG_COLOR_MASK_COLOR)
 121         channels = 3;
 122
 123      if (color_type & PNG_COLOR_MASK_ALPHA)
 124         return channels + 1;
 125
 126      else
 127         return channels;
 128   }
 129}
 130
 131static int
 132pixel_depth_of_type(int color_type, int bit_depth)
 133{
 134   return channels_of_type(color_type) * bit_depth;
 135}
 136
 137static unsigned int
 138image_size_of_type(int color_type, int bit_depth, unsigned int *colors)
 139{
 140   if (*colors)
 141      return 16;
 142
 143   else
 144   {
 145      int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
 146
 147      if (pixel_depth < 8)
 148         return 64;
 149
 150      else if (pixel_depth > 16)
 151         return 1024;
 152
 153      else
 154         return 256;
 155   }
 156}
 157
 158static void
 159set_color(png_colorp color, png_bytep trans, unsigned int red,
 160   unsigned int green, unsigned int blue, unsigned int alpha,
 161   png_const_bytep gamma_table)
 162{
 163   color->red = gamma_table[red];
 164   color->green = gamma_table[green];
 165   color->blue = gamma_table[blue];
 166   *trans = (png_byte)alpha;
 167}
 168
 169static int
 170generate_palette(png_colorp palette, png_bytep trans, int bit_depth,
 171   png_const_bytep gamma_table, unsigned int *colors)
 172{
 173   /*
 174    * 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
 175    * 2-bit: entry 0: transparent-green
 176    *        entry 1: 40%-red
 177    *        entry 2: 80%-blue
 178    *        entry 3: opaque-white
 179    * 4-bit: the 16 combinations of the 2-bit case
 180    * 8-bit: the 256 combinations of the 4-bit case
 181    */
 182   switch (colors[0])
 183   {
 184      default:
 185         fprintf(stderr, "makepng: --colors=...: invalid count %u\n",
 186            colors[0]);
 187         exit(1);
 188
 189      case 1:
 190         set_color(palette+0, trans+0, colors[1], colors[1], colors[1], 255,
 191            gamma_table);
 192         return 1;
 193
 194      case 2:
 195         set_color(palette+0, trans+0, colors[1], colors[1], colors[1],
 196            colors[2], gamma_table);
 197         return 1;
 198
 199      case 3:
 200         set_color(palette+0, trans+0, colors[1], colors[2], colors[3], 255,
 201            gamma_table);
 202         return 1;
 203
 204      case 4:
 205         set_color(palette+0, trans+0, colors[1], colors[2], colors[3],
 206            colors[4], gamma_table);
 207         return 1;
 208
 209      case 0:
 210         if (bit_depth == 1)
 211         {
 212            set_color(palette+0, trans+0, 255, 0, 0, 0, gamma_table);
 213            set_color(palette+1, trans+1, 255, 255, 255, 255, gamma_table);
 214            return 2;
 215         }
 216
 217         else
 218         {
 219            unsigned int size = 1U << (bit_depth/2); /* 2, 4 or 16 */
 220            unsigned int x, y, ip;
 221
 222            for (x=0; x<size; ++x) for (y=0; y<size; ++y)
 223            {
 224               ip = x + (size * y);
 225
 226               /* size is at most 16, so the scaled value below fits in 16 bits
 227                */
 228#              define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
 229#              define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
 230                  (interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
 231                  (size*size))
 232
 233               set_color(palette+ip, trans+ip,
 234                  /* color:    green, red,blue,white */
 235                  xyinterp(x, y,   0, 255,   0, 255),
 236                  xyinterp(x, y, 255,   0,   0, 255),
 237                  xyinterp(x, y,   0,   0, 255, 255),
 238                  /* alpha:        0, 102, 204, 255) */
 239                  xyinterp(x, y,   0, 102, 204, 255),
 240                  gamma_table);
 241            }
 242
 243            return ip+1;
 244         }
 245   }
 246}
 247
 248static void
 249set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
 250   png_uint_32 value, png_const_bytep gamma_table, double conv)
 251{
 252   unsigned int mask = (1U << bit_depth)-1;
 253
 254   x *= bit_depth;  /* Maximum x is 4*1024, maximum bit_depth is 16 */
 255
 256   if (value <= mask)
 257   {
 258      png_uint_32 offset = x >> 3;
 259
 260      if (offset < rowbytes && (bit_depth < 16 || offset+1 < rowbytes))
 261      {
 262         row += offset;
 263
 264         switch (bit_depth)
 265         {
 266            case 1:
 267            case 2:
 268            case 4:
 269               /* Don't gamma correct - values get smashed */
 270               {
 271                  unsigned int shift = (8 - bit_depth) - (x & 0x7U);
 272
 273                  mask <<= shift;
 274                  value = (value << shift) & mask;
 275                  *row = (png_byte)((*row & ~mask) | value);
 276               }
 277               return;
 278
 279            default:
 280               fprintf(stderr, "makepng: bad bit depth (internal error)\n");
 281               exit(1);
 282
 283            case 16:
 284               value = (unsigned int)floor(65535*pow(value/65535.,conv)+.5);
 285               *row++ = (png_byte)(value >> 8);
 286               *row = (png_byte)value;
 287               return;
 288
 289            case 8:
 290               *row = gamma_table[value];
 291               return;
 292         }
 293      }
 294
 295      else
 296      {
 297         fprintf(stderr, "makepng: row buffer overflow (internal error)\n");
 298         exit(1);
 299      }
 300   }
 301
 302   else
 303   {
 304      fprintf(stderr, "makepng: component overflow (internal error)\n");
 305      exit(1);
 306   }
 307}
 308
 309static void
 310generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
 311   int bit_depth, png_const_bytep gamma_table, double conv,
 312   unsigned int *colors)
 313{
 314   png_uint_32 size_max = image_size_of_type(color_type, bit_depth, colors)-1;
 315   png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
 316
 317   if (colors[0] == 0) switch (channels_of_type(color_type))
 318   {
 319   /* 1 channel: a square image with a diamond, the least luminous colors are on
 320    *    the edge of the image, the most luminous in the center.
 321    */
 322      case 1:
 323         {
 324            png_uint_32 x;
 325            png_uint_32 base = 2*size_max - abs(2*y-size_max);
 326
 327            for (x=0; x<=size_max; ++x)
 328            {
 329               png_uint_32 luma = base - abs(2*x-size_max);
 330
 331               /* 'luma' is now in the range 0..2*size_max, we need
 332                * 0..depth_max
 333                */
 334               luma = (luma*depth_max + size_max) / (2*size_max);
 335               set_value(row, rowbytes, x, bit_depth, luma, gamma_table, conv);
 336            }
 337         }
 338         break;
 339
 340   /* 2 channels: the color channel increases in luminosity from top to bottom,
 341    *    the alpha channel increases in opacity from left to right.
 342    */
 343      case 2:
 344         {
 345            png_uint_32 alpha = (depth_max * y * 2 + size_max) / (2 * size_max);
 346            png_uint_32 x;
 347
 348            for (x=0; x<=size_max; ++x)
 349            {
 350               set_value(row, rowbytes, 2*x, bit_depth,
 351                  (depth_max * x * 2 + size_max) / (2 * size_max), gamma_table,
 352                  conv);
 353               set_value(row, rowbytes, 2*x+1, bit_depth, alpha, gamma_table,
 354                  conv);
 355            }
 356         }
 357         break;
 358
 359   /* 3 channels: linear combinations of, from the top-left corner clockwise,
 360    *    black, green, white, red.
 361    */
 362      case 3:
 363         {
 364            /* x0: the black->red scale (the value of the red component) at the
 365             *     start of the row (blue and green are 0).
 366             * x1: the green->white scale (the value of the red and blue
 367             *     components at the end of the row; green is depth_max).
 368             */
 369            png_uint_32 Y = (depth_max * y * 2 + size_max) / (2 * size_max);
 370            png_uint_32 x;
 371
 372            /* Interpolate x/depth_max from start to end:
 373             *
 374             *        start end         difference
 375             * red:     Y    Y            0
 376             * green:   0   depth_max   depth_max
 377             * blue:    0    Y            Y
 378             */
 379            for (x=0; x<=size_max; ++x)
 380            {
 381               set_value(row, rowbytes, 3*x+0, bit_depth, /* red */ Y,
 382                     gamma_table, conv);
 383               set_value(row, rowbytes, 3*x+1, bit_depth, /* green */
 384                  (depth_max * x * 2 + size_max) / (2 * size_max),
 385                  gamma_table, conv);
 386               set_value(row, rowbytes, 3*x+2, bit_depth, /* blue */
 387                  (Y * x * 2 + size_max) / (2 * size_max),
 388                  gamma_table, conv);
 389            }
 390         }
 391         break;
 392
 393   /* 4 channels: linear combinations of, from the top-left corner clockwise,
 394    *    transparent, red, green, blue.
 395    */
 396      case 4:
 397         {
 398            /* x0: the transparent->blue scale (the value of the blue and alpha
 399             *     components) at the start of the row (red and green are 0).
 400             * x1: the red->green scale (the value of the red and green
 401             *     components at the end of the row; blue is 0 and alpha is
 402             *     depth_max).
 403             */
 404            png_uint_32 Y = (depth_max * y * 2 + size_max) / (2 * size_max);
 405            png_uint_32 x;
 406
 407            /* Interpolate x/depth_max from start to end:
 408             *
 409             *        start    end       difference
 410             * red:     0   depth_max-Y depth_max-Y
 411             * green:   0       Y             Y
 412             * blue:    Y       0            -Y
 413             * alpha:   Y    depth_max  depth_max-Y
 414             */
 415            for (x=0; x<=size_max; ++x)
 416            {
 417               set_value(row, rowbytes, 4*x+0, bit_depth, /* red */
 418                  ((depth_max-Y) * x * 2 + size_max) / (2 * size_max),
 419                  gamma_table, conv);
 420               set_value(row, rowbytes, 4*x+1, bit_depth, /* green */
 421                  (Y * x * 2 + size_max) / (2 * size_max),
 422                  gamma_table, conv);
 423               set_value(row, rowbytes, 4*x+2, bit_depth, /* blue */
 424                  Y - (Y * x * 2 + size_max) / (2 * size_max),
 425                  gamma_table, conv);
 426               set_value(row, rowbytes, 4*x+3, bit_depth, /* alpha */
 427                  Y + ((depth_max-Y) * x * 2 + size_max) / (2 * size_max),
 428                  gamma_table, conv);
 429            }
 430         }
 431         break;
 432
 433      default:
 434         fprintf(stderr, "makepng: internal bad channel count\n");
 435         exit(2);
 436   }
 437
 438   else if (color_type & PNG_COLOR_MASK_PALETTE)
 439   {
 440      /* Palette with fixed color: the image rows are all 0 and the image width
 441       * is 16.
 442       */
 443      memset(row, 0, rowbytes);
 444   }
 445
 446   else if (colors[0] == channels_of_type(color_type))
 447      switch (channels_of_type(color_type))
 448      {
 449         case 1:
 450            {
 451               const png_uint_32 luma = colors[1];
 452               png_uint_32 x;
 453
 454               for (x=0; x<=size_max; ++x)
 455                  set_value(row, rowbytes, x, bit_depth, luma, gamma_table,
 456                     conv);
 457            }
 458            break;
 459
 460         case 2:
 461            {
 462               const png_uint_32 luma = colors[1];
 463               const png_uint_32 alpha = colors[2];
 464               png_uint_32 x;
 465
 466               for (x=0; x<size_max; ++x)
 467               {
 468                  set_value(row, rowbytes, 2*x, bit_depth, luma, gamma_table,
 469                     conv);
 470                  set_value(row, rowbytes, 2*x+1, bit_depth, alpha, gamma_table,
 471                     conv);
 472               }
 473            }
 474            break;
 475
 476         case 3:
 477            {
 478               const png_uint_32 red = colors[1];
 479               const png_uint_32 green = colors[2];
 480               const png_uint_32 blue = colors[3];
 481               png_uint_32 x;
 482
 483               for (x=0; x<=size_max; ++x)
 484               {
 485                  set_value(row, rowbytes, 3*x+0, bit_depth, red, gamma_table,
 486                     conv);
 487                  set_value(row, rowbytes, 3*x+1, bit_depth, green, gamma_table,
 488                     conv);
 489                  set_value(row, rowbytes, 3*x+2, bit_depth, blue, gamma_table,
 490                     conv);
 491               }
 492            }
 493            break;
 494
 495         case 4:
 496            {
 497               const png_uint_32 red = colors[1];
 498               const png_uint_32 green = colors[2];
 499               const png_uint_32 blue = colors[3];
 500               const png_uint_32 alpha = colors[4];
 501               png_uint_32 x;
 502
 503               for (x=0; x<=size_max; ++x)
 504               {
 505                  set_value(row, rowbytes, 4*x+0, bit_depth, red, gamma_table,
 506                     conv);
 507                  set_value(row, rowbytes, 4*x+1, bit_depth, green, gamma_table,
 508                     conv);
 509                  set_value(row, rowbytes, 4*x+2, bit_depth, blue, gamma_table,
 510                     conv);
 511                  set_value(row, rowbytes, 4*x+3, bit_depth, alpha, gamma_table,
 512                     conv);
 513               }
 514            }
 515         break;
 516
 517         default:
 518            fprintf(stderr, "makepng: internal bad channel count\n");
 519            exit(2);
 520      }
 521
 522   else
 523   {
 524      fprintf(stderr,
 525         "makepng: --color: count(%u) does not match channels(%u)\n",
 526         colors[0], channels_of_type(color_type));
 527      exit(1);
 528   }
 529}
 530
 531
 532static void PNGCBAPI
 533makepng_warning(png_structp png_ptr, png_const_charp message)
 534{
 535   const char **ep = png_get_error_ptr(png_ptr);
 536   const char *name;
 537
 538   if (ep != NULL && *ep != NULL)
 539      name = *ep;
 540
 541   else
 542      name = "makepng";
 543
 544  fprintf(stderr, "%s: warning: %s\n", name, message);
 545}
 546
 547static void PNGCBAPI
 548makepng_error(png_structp png_ptr, png_const_charp message)
 549{
 550   makepng_warning(png_ptr, message);
 551   png_longjmp(png_ptr, 1);
 552}
 553
 554static int /* 0 on success, else an error code */
 555write_png(const char **name, FILE *fp, int color_type, int bit_depth,
 556   volatile png_fixed_point gamma, chunk_insert * volatile insert,
 557   unsigned int filters, unsigned int *colors)
 558{
 559   png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
 560      name, makepng_error, makepng_warning);
 561   volatile png_infop info_ptr = NULL;
 562   volatile png_bytep row = NULL;
 563
 564   if (png_ptr == NULL)
 565   {
 566      fprintf(stderr, "makepng: OOM allocating write structure\n");
 567      return 1;
 568   }
 569
 570   if (setjmp(png_jmpbuf(png_ptr)))
 571   {
 572      png_structp nv_ptr = png_ptr;
 573      png_infop nv_info = info_ptr;
 574
 575      png_ptr = NULL;
 576      info_ptr = NULL;
 577      png_destroy_write_struct(&nv_ptr, &nv_info);
 578      if (row != NULL) free(row);
 579      return 1;
 580   }
 581
 582   /* Allow benign errors so that we can write PNGs with errors */
 583   png_set_benign_errors(png_ptr, 1/*allowed*/);
 584   png_init_io(png_ptr, fp);
 585
 586   info_ptr = png_create_info_struct(png_ptr);
 587   if (info_ptr == NULL)
 588      png_error(png_ptr, "OOM allocating info structure");
 589
 590   {
 591      unsigned int size = image_size_of_type(color_type, bit_depth, colors);
 592      png_fixed_point real_gamma = 45455; /* For sRGB */
 593      png_byte gamma_table[256];
 594      double conv;
 595
 596      /* This function uses the libpng values used on read to carry extra
 597       * information about the gamma:
 598       */
 599      if (gamma == PNG_GAMMA_MAC_18)
 600         gamma = 65909;
 601
 602      else if (gamma > 0 && gamma < 1000)
 603         gamma = PNG_FP_1;
 604
 605      if (gamma > 0)
 606         real_gamma = gamma;
 607
 608      {
 609         unsigned int i;
 610
 611         if (real_gamma == 45455) for (i=0; i<256; ++i)
 612         {
 613            gamma_table[i] = (png_byte)i;
 614            conv = 1.;
 615         }
 616
 617         else
 618         {
 619            /* Convert 'i' from sRGB (45455) to real_gamma, this makes
 620             * the images look the same regardless of the gAMA chunk.
 621             */
 622            conv = real_gamma;
 623            conv /= 45455;
 624
 625            gamma_table[0] = 0;
 626
 627            for (i=1; i<255; ++i)
 628               gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + .5);
 629
 630            gamma_table[255] = 255;
 631         }
 632      }
 633
 634      png_set_IHDR(png_ptr, info_ptr, size, size, bit_depth, color_type,
 635         PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 636
 637      if (color_type & PNG_COLOR_MASK_PALETTE)
 638      {
 639         int npalette;
 640         png_color palette[256];
 641         png_byte trans[256];
 642
 643         npalette = generate_palette(palette, trans, bit_depth, gamma_table,
 644            colors);
 645         png_set_PLTE(png_ptr, info_ptr, palette, npalette);
 646         png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
 647            NULL/*transparent color*/);
 648
 649         /* Reset gamma_table to prevent the image rows being changed */
 650         for (npalette=0; npalette<256; ++npalette)
 651            gamma_table[npalette] = (png_byte)npalette;
 652      }
 653
 654      if (gamma == PNG_DEFAULT_sRGB)
 655         png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_ABSOLUTE);
 656
 657      else if (gamma > 0) /* Else don't set color space information */
 658      {
 659         png_set_gAMA_fixed(png_ptr, info_ptr, real_gamma);
 660
 661         /* Just use the sRGB values here. */
 662         png_set_cHRM_fixed(png_ptr, info_ptr,
 663            /* color      x       y */
 664            /* white */ 31270, 32900,
 665            /* red   */ 64000, 33000,
 666            /* green */ 30000, 60000,
 667            /* blue  */ 15000,  6000
 668         );
 669      }
 670
 671      /* Insert extra information. */
 672      while (insert != NULL)
 673      {
 674         insert->insert(png_ptr, info_ptr, insert->nparams, insert->parameters);
 675         insert = insert->next;
 676      }
 677
 678      /* Write the file header. */
 679      png_write_info(png_ptr, info_ptr);
 680
 681      /* Restrict the filters */
 682      png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, filters);
 683
 684      {
 685         int passes = png_set_interlace_handling(png_ptr);
 686         int pass;
 687         png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
 688
 689         row = malloc(rowbytes);
 690
 691         if (row == NULL)
 692            png_error(png_ptr, "OOM allocating row buffer");
 693
 694         for (pass = 0; pass < passes; ++pass)
 695         {
 696            unsigned int y;
 697
 698            for (y=0; y<size; ++y)
 699            {
 700               generate_row(row, rowbytes, y, color_type, bit_depth,
 701                  gamma_table, conv, colors);
 702               png_write_row(png_ptr, row);
 703            }
 704         }
 705      }
 706   }
 707
 708   /* Finish writing the file. */
 709   png_write_end(png_ptr, info_ptr);
 710
 711   {
 712      png_structp nv_ptr = png_ptr;
 713      png_infop nv_info = info_ptr;
 714
 715      png_ptr = NULL;
 716      info_ptr = NULL;
 717      png_destroy_write_struct(&nv_ptr, &nv_info);
 718   }
 719   free(row);
 720   return 0;
 721}
 722
 723
 724static size_t
 725load_file(png_const_charp name, png_bytepp result)
 726{
 727   FILE *fp = tmpfile();
 728
 729   if (fp != NULL)
 730   {
 731      FILE *ip = fopen(name, "rb");
 732
 733      if (ip != NULL)
 734      {
 735         size_t total = 0;
 736         int ch;
 737
 738         for (;;)
 739         {
 740            ch = getc(ip);
 741            if (ch == EOF) break;
 742            putc(ch, fp);
 743            ++total;
 744         }
 745
 746         if (ferror(ip))
 747         {
 748            perror(name);
 749            fprintf(stderr, "%s: read error\n", name);
 750            (void)fclose(ip);
 751         }
 752
 753         else
 754         {
 755            (void)fclose(ip);
 756
 757            if (ferror(fp))
 758            {
 759               perror("temporary file");
 760               fprintf(stderr, "temporary file write error\n");
 761            }
 762
 763            else
 764            {
 765               rewind(fp);
 766
 767               if (total > 0)
 768               {
 769                  /* Round up to a multiple of 4 here to allow an iCCP profile
 770                   * to be padded to a 4x boundary.
 771                   */
 772                  png_bytep data = malloc((total+3)&~3);
 773
 774                  if (data != NULL)
 775                  {
 776                     size_t new_size = 0;
 777
 778                     for (;;)
 779                     {
 780                        ch = getc(fp);
 781                        if (ch == EOF) break;
 782                        data[new_size++] = (png_byte)ch;
 783                     }
 784
 785                     if (ferror(fp) || new_size != total)
 786                     {
 787                        perror("temporary file");
 788                        fprintf(stderr, "temporary file read error\n");
 789                        free(data);
 790                     }
 791
 792                     else
 793                     {
 794                        (void)fclose(fp);
 795                        *result = data;
 796                        return total;
 797                     }
 798                  }
 799
 800                  else
 801                     fprintf(stderr, "%s: out of memory loading file\n", name);
 802               }
 803
 804               else
 805                  fprintf(stderr, "%s: empty file\n", name);
 806            }
 807         }
 808      }
 809
 810      else
 811      {
 812         perror(name);
 813         fprintf(stderr, "%s: open failed\n", name);
 814      }
 815
 816      fclose(fp);
 817   }
 818
 819   else
 820      fprintf(stderr, "makepng: %s: could not open temporary file\n", name);
 821
 822   exit(1);
 823   return 0;
 824}
 825
 826static png_size_t
 827load_fake(png_charp param, png_bytepp profile)
 828{
 829   char *endptr = NULL;
 830   unsigned long long int size = strtoull(param, &endptr, 0/*base*/);
 831
 832   /* The 'fake' format is <number>*[string] */
 833   if (endptr != NULL && *endptr == '*')
 834   {
 835      size_t len = strlen(++endptr);
 836      size_t result = (size_t)size;
 837
 838      if (len == 0) len = 1; /* capture the terminating '\0' */
 839
 840      /* Now repeat that string to fill 'size' bytes. */
 841      if (result == size && (*profile = malloc(result)) != NULL)
 842      {
 843         png_bytep out = *profile;
 844
 845         if (len == 1)
 846            memset(out, *endptr, result);
 847
 848         else
 849         {
 850            while (size >= len)
 851            {
 852               memcpy(out, endptr, len);
 853               out += len;
 854               size -= len;
 855            }
 856            memcpy(out, endptr, size);
 857         }
 858
 859         return result;
 860      }
 861
 862      else
 863      {
 864         fprintf(stderr, "%s: size exceeds system limits\n", param);
 865         exit(1);
 866      }
 867   }
 868
 869   return 0;
 870}
 871
 872static void
 873check_param_count(int nparams, int expect)
 874{
 875   if (nparams != expect)
 876   {
 877      fprintf(stderr, "bad parameter count (internal error)\n");
 878      exit(1);
 879   }
 880}
 881
 882static void
 883insert_iCCP(png_structp png_ptr, png_infop info_ptr, int nparams,
 884   png_charpp params)
 885{
 886   png_bytep profile = NULL;
 887   png_uint_32 proflen = 0;
 888   int result;
 889
 890   check_param_count(nparams, 2);
 891
 892   switch (params[1][0])
 893   {
 894      case '<':
 895         {
 896            png_size_t filelen = load_file(params[1]+1, &profile);
 897            if (filelen > 0xfffffffc) /* Maximum profile length */
 898            {
 899               fprintf(stderr, "%s: file too long (%lu) for an ICC profile\n",
 900                  params[1]+1, (unsigned long)filelen);
 901               exit(1);
 902            }
 903
 904            proflen = (png_uint_32)filelen;
 905         }
 906         break;
 907
 908      case '0': case '1': case '2': case '3': case '4':
 909      case '5': case '6': case '7': case '8': case '9':
 910         {
 911            png_size_t fake_len = load_fake(params[1], &profile);
 912
 913            if (fake_len > 0) /* else a simple parameter */
 914            {
 915               if (fake_len > 0xffffffff) /* Maximum profile length */
 916               {
 917                  fprintf(stderr,
 918                     "%s: fake data too long (%lu) for an ICC profile\n",
 919                     params[1], (unsigned long)fake_len);
 920                  exit(1);
 921               }
 922               proflen = (png_uint_32)(fake_len & ~3U);
 923               /* Always fix up the profile length. */
 924               png_save_uint_32(profile, proflen);
 925               break;
 926            }
 927         }
 928
 929      default:
 930         fprintf(stderr, "--insert iCCP \"%s\": unrecognized\n", params[1]);
 931         fprintf(stderr, "  use '<' to read a file: \"<filename\"\n");
 932         exit(1);
 933   }
 934
 935   result = 1;
 936
 937   if (proflen & 3)
 938   {
 939      fprintf(stderr,
 940         "makepng: --insert iCCP %s: profile length made a multiple of 4\n",
 941         params[1]);
 942
 943      /* load_file allocates extra space for this padding, the ICC spec requires
 944       * padding with zero bytes.
 945       */
 946      while (proflen & 3)
 947         profile[proflen++] = 0;
 948   }
 949
 950   if (profile != NULL && proflen > 3)
 951   {
 952      png_uint_32 prof_header = png_get_uint_32(profile);
 953
 954      if (prof_header != proflen)
 955      {
 956         fprintf(stderr, "--insert iCCP %s: profile length field wrong:\n",
 957            params[1]);
 958         fprintf(stderr, "  actual %lu, recorded value %lu (corrected)\n",
 959            (unsigned long)proflen, (unsigned long)prof_header);
 960         png_save_uint_32(profile, proflen);
 961      }
 962   }
 963
 964   if (result && profile != NULL && proflen >=4)
 965      png_set_iCCP(png_ptr, info_ptr, params[0], PNG_COMPRESSION_TYPE_BASE,
 966         profile, proflen);
 967
 968   if (profile)
 969      free(profile);
 970
 971   if (!result)
 972      exit(1);
 973}
 974
 975static void
 976clear_text(png_text *text, png_charp keyword)
 977{
 978   text->compression = -1; /* none */
 979   text->key = keyword;
 980   text->text = NULL;
 981   text->text_length = 0; /* libpng calculates this */
 982   text->itxt_length = 0; /* libpng calculates this */
 983   text->lang = NULL;
 984   text->lang_key = NULL;
 985}
 986
 987static void
 988set_text(png_structp png_ptr, png_infop info_ptr, png_textp text,
 989   png_charp param)
 990{
 991   switch (param[0])
 992   {
 993      case '<':
 994         {
 995            png_bytep file = NULL;
 996
 997            text->text_length = load_file(param+1, &file);
 998            text->text = (png_charp)file;
 999         }
1000         break;
1001
1002      case '0': case '1': case '2': case '3': case '4':
1003      case '5': case '6': case '7': case '8': case '9':
1004         {
1005            png_bytep data = NULL;
1006            png_size_t fake_len = load_fake(param, &data);
1007
1008            if (fake_len > 0) /* else a simple parameter */
1009            {
1010               text->text_length = fake_len;
1011               text->text = (png_charp)data;
1012               break;
1013            }
1014         }
1015
1016      default:
1017         text->text = param;
1018         break;
1019   }
1020
1021   png_set_text(png_ptr, info_ptr, text, 1);
1022
1023   if (text->text != param)
1024      free(text->text);
1025}
1026
1027static void
1028insert_tEXt(png_structp png_ptr, png_infop info_ptr, int nparams,
1029   png_charpp params)
1030{
1031   png_text text;
1032
1033   check_param_count(nparams, 2);
1034   clear_text(&text, params[0]);
1035   set_text(png_ptr, info_ptr, &text, params[1]);
1036}
1037
1038static void
1039insert_zTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
1040   png_charpp params)
1041{
1042   png_text text;
1043
1044   check_param_count(nparams, 2);
1045   clear_text(&text, params[0]);
1046   text.compression = 0; /* deflate */
1047   set_text(png_ptr, info_ptr, &text, params[1]);
1048}
1049
1050static void
1051insert_iTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
1052   png_charpp params)
1053{
1054   png_text text;
1055
1056   check_param_count(nparams, 4);
1057   clear_text(&text, params[0]);
1058   text.compression = 2; /* iTXt + deflate */
1059   text.lang = params[1];/* language tag */
1060   text.lang_key = params[2]; /* translated keyword */
1061   set_text(png_ptr, info_ptr, &text, params[3]);
1062}
1063
1064static void
1065insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
1066{
1067   int i;
1068   png_uint_16 freq[256];
1069
1070   /* libpng takes the count from the PLTE count; we don't check it here but we
1071    * do set the array to 0 for unspecified entries.
1072    */
1073   memset(freq, 0, sizeof freq);
1074   for (i=0; i<nparams; ++i)
1075   {
1076      char *endptr = NULL;
1077      unsigned long int l = strtoul(params[i], &endptr, 0/*base*/);
1078
1079      if (params[i][0] && *endptr == 0 && l <= 65535)
1080         freq[i] = (png_uint_16)l;
1081
1082      else
1083      {
1084         fprintf(stderr, "hIST[%d]: %s: invalid frequency\n", i, params[i]);
1085         exit(1);
1086      }
1087   }
1088
1089   png_set_hIST(png_ptr, info_ptr, freq);
1090}
1091
1092#if 0
1093static void
1094insert_sPLT(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
1095{
1096   fprintf(stderr, "insert sPLT: NYI\n");
1097}
1098#endif
1099
1100static int
1101find_parameters(png_const_charp what, png_charp param, png_charp *list,
1102   int nparams)
1103{
1104   /* Parameters are separated by '\n' or ':' characters, up to nparams are
1105    * accepted (more is an error) and the number found is returned.
1106    */
1107   int i;
1108   for (i=0; *param && i<nparams; ++i)
1109   {
1110      list[i] = param;
1111      while (*++param) if (*param == '\n' || *param == ':')
1112      {
1113         *param++ = 0; /* Terminate last parameter */
1114         break;        /* And start a new one. */
1115      }
1116   }
1117
1118   if (*param)
1119   {
1120      fprintf(stderr, "--insert %s: too many parameters (%s)\n", what, param);
1121      exit(1);
1122   }
1123
1124   list[i] = NULL; /* terminates list */
1125   return i; /* number of parameters filled in */
1126}
1127
1128static void
1129bad_parameter_count(png_const_charp what, int nparams)
1130{
1131   fprintf(stderr, "--insert %s: bad parameter count %d\n", what, nparams);
1132   exit(1);
1133}
1134
1135static chunk_insert *
1136make_insert(png_const_charp what,
1137   void (*insert)(png_structp, png_infop, int, png_charpp),
1138   int nparams, png_charpp list)
1139{
1140   int i;
1141   chunk_insert *cip;
1142
1143   cip = malloc(offsetof(chunk_insert,parameters) +
1144      nparams * sizeof (png_charp));
1145
1146   if (cip == NULL)
1147   {
1148      fprintf(stderr, "--insert %s: out of memory allocating %d parameters\n",
1149         what, nparams);
1150      exit(1);
1151   }
1152
1153   cip->next = NULL;
1154   cip->insert = insert;
1155   cip->nparams = nparams;
1156   for (i=0; i<nparams; ++i)
1157      cip->parameters[i] = list[i];
1158
1159   return cip;
1160}
1161
1162static chunk_insert *
1163find_insert(png_const_charp what, png_charp param)
1164{
1165   png_uint_32 chunk = 0;
1166   png_charp parameter_list[1024];
1167   int i, nparams;
1168
1169   /* Assemble the chunk name */
1170   for (i=0; i<4; ++i)
1171   {
1172      char ch = what[i];
1173
1174      if ((ch >= 65 && ch <= 90) || (ch >= 97 && ch <= 122))
1175         chunk = (chunk << 8) + what[i];
1176
1177      else
1178         break;
1179   }
1180
1181   if (i < 4 || what[4] != 0)
1182   {
1183      fprintf(stderr, "makepng --insert \"%s\": invalid chunk name\n", what);
1184      exit(1);
1185   }
1186
1187   /* Assemble the parameter list. */
1188   nparams = find_parameters(what, param, parameter_list, 1024);
1189
1190#  define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))
1191
1192   switch (chunk)
1193   {
1194      case CHUNK(105,67,67,80):  /* iCCP */
1195         if (nparams == 2)
1196            return make_insert(what, insert_iCCP, nparams, parameter_list);
1197         break;
1198
1199      case CHUNK(116,69,88,116): /* tEXt */
1200         if (nparams == 2)
1201            return make_insert(what, insert_tEXt, nparams, parameter_list);
1202         break;
1203
1204      case CHUNK(122,84,88,116): /* zTXt */
1205         if (nparams == 2)
1206            return make_insert(what, insert_zTXt, nparams, parameter_list);
1207         break;
1208
1209      case CHUNK(105,84,88,116): /* iTXt */
1210         if (nparams == 4)
1211            return make_insert(what, insert_iTXt, nparams, parameter_list);
1212         break;
1213
1214      case CHUNK(104,73,83,84):  /* hIST */
1215         if (nparams <= 256)
1216            return make_insert(what, insert_hIST, nparams, parameter_list);
1217         break;
1218
1219#if 0
1220      case CHUNK(115,80,76,84):  /* sPLT */
1221         return make_insert(what, insert_sPLT, nparams, parameter_list);
1222#endif
1223
1224      default:
1225         fprintf(stderr, "makepng --insert \"%s\": unrecognized chunk name\n",
1226            what);
1227         exit(1);
1228   }
1229
1230   bad_parameter_count(what, nparams);
1231   return NULL;
1232}
1233
1234/* This is a not-very-good parser for a sequence of numbers (including 0).  It
1235 * doesn't accept some apparently valid things, but it accepts all the sensible
1236 * combinations.
1237 */
1238static void
1239parse_color(char *arg, unsigned int *colors)
1240{
1241   unsigned int ncolors = 0;
1242
1243   while (*arg && ncolors < 4)
1244   {
1245      char *ep = arg;
1246
1247      unsigned long ul = strtoul(arg, &ep, 0);
1248
1249      if (ul > 65535)
1250      {
1251         fprintf(stderr, "makepng --color=...'%s': too big\n", arg);
1252         exit(1);
1253      }
1254
1255      if (ep == arg)
1256      {
1257         fprintf(stderr, "makepng --color=...'%s': not a valid color\n", arg);
1258         exit(1);
1259      }
1260
1261      if (*ep) ++ep; /* skip a separator */
1262      arg = ep;
1263
1264      colors[++ncolors] = (unsigned int)ul; /* checked above */
1265   }
1266
1267   if (*arg)
1268   {
1269      fprintf(stderr, "makepng --color=...'%s': too many values\n", arg);
1270      exit(1);
1271   }
1272
1273   *colors = ncolors;
1274}
1275
1276int
1277main(int argc, char **argv)
1278{
1279   FILE *fp = stdout;
1280   const char *file_name = NULL;
1281   int color_type = 8; /* invalid */
1282   int bit_depth = 32; /* invalid */
1283   unsigned int colors[5];
1284   unsigned int filters = PNG_ALL_FILTERS;
1285   png_fixed_point gamma = 0; /* not set */
1286   chunk_insert *head_insert = NULL;
1287   chunk_insert **insert_ptr = &head_insert;
1288
1289   memset(colors, 0, sizeof colors);
1290
1291   while (--argc > 0)
1292   {
1293      char *arg = *++argv;
1294
1295      if (strcmp(arg, "--sRGB") == 0)
1296      {
1297         gamma = PNG_DEFAULT_sRGB;
1298         continue;
1299      }
1300
1301      if (strcmp(arg, "--linear") == 0)
1302      {
1303         gamma = PNG_FP_1;
1304         continue;
1305      }
1306
1307      if (strcmp(arg, "--1.8") == 0)
1308      {
1309         gamma = PNG_GAMMA_MAC_18;
1310         continue;
1311      }
1312
1313      if (strcmp(arg, "--nofilters") == 0)
1314      {
1315         filters = PNG_FILTER_NONE;
1316         continue;
1317      }
1318
1319      if (strncmp(arg, "--color=", 8) == 0)
1320      {
1321          parse_color(arg+8, colors);
1322          continue;
1323      }
1324
1325      if (argc >= 3 && strcmp(arg, "--insert") == 0)
1326      {
1327         png_const_charp what = *++argv;
1328         png_charp param = *++argv;
1329         chunk_insert *new_insert;
1330
1331         argc -= 2;
1332
1333         new_insert = find_insert(what, param);
1334
1335         if (new_insert != NULL)
1336         {
1337            *insert_ptr = new_insert;
1338            insert_ptr = &new_insert->next;
1339         }
1340
1341         continue;
1342      }
1343
1344      if (arg[0] == '-')
1345      {
1346         fprintf(stderr, "makepng: %s: invalid option\n", arg);
1347         exit(1);
1348      }
1349
1350      if (strcmp(arg, "palette") == 0)
1351      {
1352         color_type = PNG_COLOR_TYPE_PALETTE;
1353         continue;
1354      }
1355
1356      if (strncmp(arg, "gray", 4) == 0)
1357      {
1358         if (arg[4] == 0)
1359         {
1360            color_type = PNG_COLOR_TYPE_GRAY;
1361            continue;
1362         }
1363
1364         else if (strcmp(arg+4, "a") == 0 ||
1365            strcmp(arg+4, "alpha") == 0 ||
1366            strcmp(arg+4, "-alpha") == 0)
1367         {
1368            color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
1369            continue;
1370         }
1371      }
1372
1373      if (strncmp(arg, "rgb", 3) == 0)
1374      {
1375         if (arg[3] == 0)
1376         {
1377            color_type = PNG_COLOR_TYPE_RGB;
1378            continue;
1379         }
1380
1381         else if (strcmp(arg+3, "a") == 0 ||
1382            strcmp(arg+3, "alpha") == 0 ||
1383            strcmp(arg+3, "-alpha") == 0)
1384         {
1385            color_type = PNG_COLOR_TYPE_RGB_ALPHA;
1386            continue;
1387         }
1388      }
1389
1390      if (color_type == 8 && isdigit(arg[0]))
1391      {
1392         color_type = atoi(arg);
1393         if (color_type < 0 || color_type > 6 || color_type == 1 ||
1394            color_type == 5)
1395         {
1396            fprintf(stderr, "makepng: %s: not a valid color type\n", arg);
1397            exit(1);
1398         }
1399
1400         continue;
1401      }
1402
1403      if (bit_depth == 32 && isdigit(arg[0]))
1404      {
1405         bit_depth = atoi(arg);
1406         if (bit_depth <= 0 || bit_depth > 16 ||
1407            (bit_depth & -bit_depth) != bit_depth)
1408         {
1409            fprintf(stderr, "makepng: %s: not a valid bit depth\n", arg);
1410            exit(1);
1411         }
1412
1413         continue;
1414      }
1415
1416      if (argc == 1) /* It's the file name */
1417      {
1418         fp = fopen(arg, "wb");
1419         if (fp == NULL)
1420         {
1421            fprintf(stderr, "%s: %s: could not open\n", arg, strerror(errno));
1422            exit(1);
1423         }
1424
1425         file_name = arg;
1426         continue;
1427      }
1428
1429      fprintf(stderr, "makepng: %s: unknown argument\n", arg);
1430      exit(1);
1431   } /* argument while loop */
1432
1433   if (color_type == 8 || bit_depth == 32)
1434   {
1435      fprintf(stderr, "usage: makepng [--sRGB|--linear|--1.8] "
1436         "[--color=...] color-type bit-depth [file-name]\n"
1437         "  Make a test PNG file, by default writes to stdout.\n");
1438      exit(1);
1439   }
1440
1441   /* Check the colors */
1442   {
1443      const unsigned int lim = (color_type == PNG_COLOR_TYPE_PALETTE ? 255U :
1444         (1U<<bit_depth)-1);
1445      unsigned int i;
1446
1447      for (i=1; i<=colors[0]; ++i)
1448         if (colors[i] > lim)
1449         {
1450            fprintf(stderr, "makepng: --color=...: %u out of range [0..%u]\n",
1451               colors[i], lim);
1452            exit(1);
1453         }
1454   }
1455
1456   /* Restrict the filters for more speed to those we know are used for the
1457    * generated images.
1458    */
1459   if (filters == PNG_ALL_FILTERS)
1460   {
1461      if ((color_type & PNG_COLOR_MASK_PALETTE) != 0 || bit_depth < 8)
1462         filters = PNG_FILTER_NONE;
1463
1464      else if (color_type & PNG_COLOR_MASK_COLOR) /* rgb */
1465      {
1466         if (bit_depth == 8)
1467            filters &= ~(PNG_FILTER_NONE | PNG_FILTER_AVG);
1468
1469         else
1470            filters = PNG_FILTER_SUB | PNG_FILTER_PAETH;
1471      }
1472
1473      else /* gray 8 or 16-bit */
1474         filters &= ~PNG_FILTER_NONE;
1475   }
1476
1477   {
1478      int ret = write_png(&file_name, fp, color_type, bit_depth, gamma,
1479         head_insert, filters, colors);
1480
1481      if (ret != 0 && file_name != NULL)
1482         remove(file_name);
1483
1484      return ret;
1485   }
1486}