workbench/libs/png/contrib/libtests/pngunknown.c

   1
   2 /* pngunknown.c - test the read side unknown chunk handling
   3  *
   4  * Last changed in libpng 1.6.32 [August 24, 2017]
   5  * Copyright (c) 2015,2017 Glenn Randers-Pehrson
   6  * Written by John Cunningham Bowler
   7  *
   8  * This code is released under the libpng license.
   9  * For conditions of distribution and use, see the disclaimer
  10  * and license in png.h
  11  *
  12  * NOTES:
  13  *   This is a C program that is intended to be linked against libpng.  It
  14  *   allows the libpng unknown handling code to be tested by interpreting
  15  *   arguments to save or discard combinations of chunks.  The program is
  16  *   currently just a minimal validation for the built-in libpng facilities.
  17  */
  18
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <stdio.h>
  22 #include <setjmp.h>
  23
  24 /* Define the following to use this test against your installed libpng, rather
  25  * than the one being built here:
  26  */
  27 #ifdef PNG_FREESTANDING_TESTS
  28 #  include <png.h>
  29 #else
  30 #  include "../../png.h"
  31 #endif
  32
  33 /* 1.6.1 added support for the configure test harness, which uses 77 to indicate
  34  * a skipped test, in earlier versions we need to succeed on a skipped test, so:
  35  */
  36 #if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
  37 #  define SKIP 77
  38 #else
  39 #  define SKIP 0
  40 #endif
  41
  42
  43 /* Since this program tests the ability to change the unknown chunk handling
  44  * these must be defined:
  45  */
  46 #if defined(PNG_SET_UNKNOWN_CHUNKS_SUPPORTED) &&\
  47    defined(PNG_STDIO_SUPPORTED) &&\
  48    defined(PNG_READ_SUPPORTED)
  49
  50 /* One of these must be defined to allow us to find out what happened.  It is
  51  * still useful to set unknown chunk handling without either of these in order
  52  * to cause *known* chunks to be discarded.  This can be a significant
  53  * efficiency gain, but it can't really be tested here.
  54  */
  55 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED) ||\
  56    defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
  57
  58 #if PNG_LIBPNG_VER < 10500
  59 /* This deliberately lacks the const. */
  60 typedef png_byte *png_const_bytep;
  61
  62 /* This is copied from 1.5.1 png.h: */
  63 #define PNG_INTERLACE_ADAM7_PASSES 7
  64 #define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7)
  65 #define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7)
  66 #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
  67 #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
  68 #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
  69    -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
  70 #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
  71    -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
  72 #define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
  73    (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
  74 #define PNG_COL_FROM_PASS_COL(xIn, pass) \
  75    (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
  76 #define PNG_PASS_MASK(pass,off) ( \
  77    ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \
  78    ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U))
  79 #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
  80    ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
  81 #define PNG_COL_IN_INTERLACE_PASS(x, pass) \
  82    ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
  83
  84 /* These are needed too for the default build: */
  85 #define PNG_WRITE_16BIT_SUPPORTED
  86 #define PNG_READ_16BIT_SUPPORTED
  87
  88 /* This comes from pnglibconf.h after 1.5: */
  89 #define PNG_FP_1 100000
  90 #define PNG_GAMMA_THRESHOLD_FIXED\
  91    ((png_fixed_point)(PNG_GAMMA_THRESHOLD * PNG_FP_1))
  92 #endif
  93
  94 #if PNG_LIBPNG_VER < 10600
  95    /* 1.6.0 constifies many APIs. The following exists to allow pngvalid to be
  96     * compiled against earlier versions.
  97     */
  98 #  define png_const_structp png_structp
  99 #endif
 100
 101 #if PNG_LIBPNG_VER < 10700
 102    /* Copied from libpng 1.7.0 png.h */
 103 #define PNG_u2(b1, b2) (((unsigned int)(b1) << 8) + (b2))
 104
 105 #define PNG_U16(b1, b2) ((png_uint_16)PNG_u2(b1, b2))
 106 #define PNG_U32(b1, b2, b3, b4)\
 107    (((png_uint_32)PNG_u2(b1, b2) << 16) + PNG_u2(b3, b4))
 108
 109 /* Constants for known chunk types.
 110  */
 111 #define png_IDAT PNG_U32( 73,  68,  65,  84)
 112 #define png_IEND PNG_U32( 73,  69,  78,  68)
 113 #define png_IHDR PNG_U32( 73,  72,  68,  82)
 114 #define png_PLTE PNG_U32( 80,  76,  84,  69)
 115 #define png_bKGD PNG_U32( 98,  75,  71,  68)
 116 #define png_cHRM PNG_U32( 99,  72,  82,  77)
 117 #define png_eXIf PNG_U32(101,  88,  73, 102) /* registered July 2017 */
 118 #define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
 119 #define png_gAMA PNG_U32(103,  65,  77,  65)
 120 #define png_gIFg PNG_U32(103,  73,  70, 103)
 121 #define png_gIFt PNG_U32(103,  73,  70, 116) /* deprecated */
 122 #define png_gIFx PNG_U32(103,  73,  70, 120)
 123 #define png_hIST PNG_U32(104,  73,  83,  84)
 124 #define png_iCCP PNG_U32(105,  67,  67,  80)
 125 #define png_iTXt PNG_U32(105,  84,  88, 116)
 126 #define png_oFFs PNG_U32(111,  70,  70, 115)
 127 #define png_pCAL PNG_U32(112,  67,  65,  76)
 128 #define png_pHYs PNG_U32(112,  72,  89, 115)
 129 #define png_sBIT PNG_U32(115,  66,  73,  84)
 130 #define png_sCAL PNG_U32(115,  67,  65,  76)
 131 #define png_sPLT PNG_U32(115,  80,  76,  84)
 132 #define png_sRGB PNG_U32(115,  82,  71,  66)
 133 #define png_sTER PNG_U32(115,  84,  69,  82)
 134 #define png_tEXt PNG_U32(116,  69,  88, 116)
 135 #define png_tIME PNG_U32(116,  73,  77,  69)
 136 #define png_tRNS PNG_U32(116,  82,  78,  83)
 137 #define png_zTXt PNG_U32(122,  84,  88, 116)
 138
 139 /* Test on flag values as defined in the spec (section 5.4): */
 140 #define PNG_CHUNK_ANCILLARY(c)    (1 & ((c) >> 29))
 141 #define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
 142 #define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
 143 #define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
 144 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
 145
 146 #endif /* PNG_LIBPNG_VER < 10700 */
 147
 148 #ifdef __cplusplus
 149 #  define this not_the_cpp_this
 150 #  define new not_the_cpp_new
 151 #  define voidcast(type, value) static_cast<type>(value)
 152 #else
 153 #  define voidcast(type, value) (value)
 154 #endif /* __cplusplus */
 155
 156 /* Unused formal parameter errors are removed using the following macro which is
 157  * expected to have no bad effects on performance.
 158  */
 159 #ifndef UNUSED
 160 #  if defined(__GNUC__) || defined(_MSC_VER)
 161 #     define UNUSED(param) (void)param;
 162 #  else
 163 #     define UNUSED(param)
 164 #  endif
 165 #endif
 166
 167 /* Types of chunks not known to libpng */
 168 #define png_vpAg PNG_U32(118, 112, 65, 103)
 169
 170 /* Chunk information */
 171 #define PNG_INFO_tEXt 0x10000000U
 172 #define PNG_INFO_iTXt 0x20000000U
 173 #define PNG_INFO_zTXt 0x40000000U
 174
 175 #define PNG_INFO_sTER 0x01000000U
 176 #define PNG_INFO_vpAg 0x02000000U
 177
 178 #define ABSENT  0
 179 #define START   1
 180 #define END     2
 181
 182 static struct
 183 {
 184    char        name[5];
 185    png_uint_32 flag;
 186    png_uint_32 tag;
 187    int         unknown;    /* Chunk not known to libpng */
 188    int         all;        /* Chunk set by the '-1' option */
 189    int         position;   /* position in pngtest.png */
 190    int         keep;       /* unknown handling setting */
 191 } chunk_info[] = {
 192    /* Critical chunks */
 193    { "IDAT", PNG_INFO_IDAT, png_IDAT, 0, 0,  START, 0 }, /* must be [0] */
 194    { "PLTE", PNG_INFO_PLTE, png_PLTE, 0, 0, ABSENT, 0 },
 195
 196    /* Non-critical chunks that libpng handles */
 197    /* This is a mess but it seems to be the only way to do it - there is no way
 198     * to check for a definition outside a #if.
 199     */
 200    { "bKGD", PNG_INFO_bKGD, png_bKGD,
 201 #     ifdef PNG_READ_bKGD_SUPPORTED
 202          0,
 203 #     else
 204          1,
 205 #     endif
 206       1,  START, 0 },
 207    { "cHRM", PNG_INFO_cHRM, png_cHRM,
 208 #     ifdef PNG_READ_cHRM_SUPPORTED
 209          0,
 210 #     else
 211          1,
 212 #     endif
 213       1,  START, 0 },
 214    { "eXIf", PNG_INFO_eXIf, png_eXIf,
 215 #     ifdef PNG_READ_eXIf_SUPPORTED
 216          0,
 217 #     else
 218          1,
 219 #     endif
 220       1,  END, 0 },
 221    { "gAMA", PNG_INFO_gAMA, png_gAMA,
 222 #     ifdef PNG_READ_gAMA_SUPPORTED
 223          0,
 224 #     else
 225          1,
 226 #     endif
 227       1,  START, 0 },
 228    { "hIST", PNG_INFO_hIST, png_hIST,
 229 #     ifdef PNG_READ_hIST_SUPPORTED
 230          0,
 231 #     else
 232          1,
 233 #     endif
 234       1, ABSENT, 0 },
 235    { "iCCP", PNG_INFO_iCCP, png_iCCP,
 236 #     ifdef PNG_READ_iCCP_SUPPORTED
 237          0,
 238 #     else
 239          1,
 240 #     endif
 241       1, ABSENT, 0 },
 242    { "iTXt", PNG_INFO_iTXt, png_iTXt,
 243 #     ifdef PNG_READ_iTXt_SUPPORTED
 244          0,
 245 #     else
 246          1,
 247 #     endif
 248       1, ABSENT, 0 },
 249    { "oFFs", PNG_INFO_oFFs, png_oFFs,
 250 #     ifdef PNG_READ_oFFs_SUPPORTED
 251          0,
 252 #     else
 253          1,
 254 #     endif
 255       1,  START, 0 },
 256    { "pCAL", PNG_INFO_pCAL, png_pCAL,
 257 #     ifdef PNG_READ_pCAL_SUPPORTED
 258          0,
 259 #     else
 260          1,
 261 #     endif
 262       1,  START, 0 },
 263    { "pHYs", PNG_INFO_pHYs, png_pHYs,
 264 #     ifdef PNG_READ_pHYs_SUPPORTED
 265          0,
 266 #     else
 267          1,
 268 #     endif
 269       1,  START, 0 },
 270    { "sBIT", PNG_INFO_sBIT, png_sBIT,
 271 #     ifdef PNG_READ_sBIT_SUPPORTED
 272          0,
 273 #     else
 274          1,
 275 #     endif
 276       1,  START, 0 },
 277    { "sCAL", PNG_INFO_sCAL, png_sCAL,
 278 #     ifdef PNG_READ_sCAL_SUPPORTED
 279          0,
 280 #     else
 281          1,
 282 #     endif
 283       1,  START, 0 },
 284    { "sPLT", PNG_INFO_sPLT, png_sPLT,
 285 #     ifdef PNG_READ_sPLT_SUPPORTED
 286          0,
 287 #     else
 288          1,
 289 #     endif
 290       1, ABSENT, 0 },
 291    { "sRGB", PNG_INFO_sRGB, png_sRGB,
 292 #     ifdef PNG_READ_sRGB_SUPPORTED
 293          0,
 294 #     else
 295          1,
 296 #     endif
 297       1,  START, 0 },
 298    { "tEXt", PNG_INFO_tEXt, png_tEXt,
 299 #     ifdef PNG_READ_tEXt_SUPPORTED
 300          0,
 301 #     else
 302          1,
 303 #     endif
 304       1,  START, 0 },
 305    { "tIME", PNG_INFO_tIME, png_tIME,
 306 #     ifdef PNG_READ_tIME_SUPPORTED
 307          0,
 308 #     else
 309          1,
 310 #     endif
 311       1,  START, 0 },
 312    { "tRNS", PNG_INFO_tRNS, png_tRNS,
 313 #     ifdef PNG_READ_tRNS_SUPPORTED
 314          0,
 315 #     else
 316          1,
 317 #     endif
 318       0, ABSENT, 0 },
 319    { "zTXt", PNG_INFO_zTXt, png_zTXt,
 320 #     ifdef PNG_READ_zTXt_SUPPORTED
 321          0,
 322 #     else
 323          1,
 324 #     endif
 325       1,    END, 0 },
 326
 327    /* No libpng handling */
 328    { "sTER", PNG_INFO_sTER, png_sTER, 1, 1,  START, 0 },
 329    { "vpAg", PNG_INFO_vpAg, png_vpAg, 1, 0,  START, 0 },
 330 };
 331
 332 #define NINFO ((int)((sizeof chunk_info)/(sizeof chunk_info[0])))
 333
 334 static void
 335 clear_keep(void)
 336 {
 337    int i = NINFO;
 338    while (--i >= 0)
 339       chunk_info[i].keep = 0;
 340 }
 341
 342 static int
 343 find(const char *name)
 344 {
 345    int i = NINFO;
 346    while (--i >= 0)
 347    {
 348       if (memcmp(chunk_info[i].name, name, 4) == 0)
 349          break;
 350    }
 351
 352    return i;
 353 }
 354
 355 static int
 356 findb(const png_byte *name)
 357 {
 358    int i = NINFO;
 359    while (--i >= 0)
 360    {
 361       if (memcmp(chunk_info[i].name, name, 4) == 0)
 362          break;
 363    }
 364
 365    return i;
 366 }
 367
 368 static int
 369 find_by_flag(png_uint_32 flag)
 370 {
 371    int i = NINFO;
 372
 373    while (--i >= 0) if (chunk_info[i].flag == flag) return i;
 374
 375    fprintf(stderr, "pngunknown: internal error\n");
 376    exit(4);
 377 }
 378
 379 static int
 380 ancillary(const char *name)
 381 {
 382    return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 383 }
 384
 385 #ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 386 static int
 387 ancillaryb(const png_byte *name)
 388 {
 389    return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 390 }
 391 #endif
 392
 393 /* Type of an error_ptr */
 394 typedef struct
 395 {
 396    jmp_buf     error_return;
 397    png_structp png_ptr;
 398    png_infop   info_ptr, end_ptr;
 399    png_uint_32 before_IDAT;
 400    png_uint_32 after_IDAT;
 401    int         error_count;
 402    int         warning_count;
 403    int         keep; /* the default value */
 404    const char *program;
 405    const char *file;
 406    const char *test;
 407 } display;
 408
 409 static const char init[] = "initialization";
 410 static const char cmd[] = "command line";
 411
 412 static void
 413 init_display(display *d, const char *program)
 414 {
 415    memset(d, 0, sizeof *d);
 416    d->png_ptr = NULL;
 417    d->info_ptr = d->end_ptr = NULL;
 418    d->error_count = d->warning_count = 0;
 419    d->program = program;
 420    d->file = program;
 421    d->test = init;
 422 }
 423
 424 static void
 425 clean_display(display *d)
 426 {
 427    png_destroy_read_struct(&d->png_ptr, &d->info_ptr, &d->end_ptr);
 428
 429    /* This must not happen - it might cause an app crash */
 430    if (d->png_ptr != NULL || d->info_ptr != NULL || d->end_ptr != NULL)
 431    {
 432       fprintf(stderr, "%s(%s): png_destroy_read_struct error\n", d->file,
 433          d->test);
 434       exit(1);
 435    }
 436 }
 437
 438 PNG_FUNCTION(void, display_exit, (display *d), static PNG_NORETURN)
 439 {
 440    ++(d->error_count);
 441
 442    if (d->png_ptr != NULL)
 443       clean_display(d);
 444
 445    /* During initialization and if this is a single command line argument set
 446     * exit now - there is only one test, otherwise longjmp to do the next test.
 447     */
 448    if (d->test == init || d->test == cmd)
 449       exit(1);
 450
 451    longjmp(d->error_return, 1);
 452 }
 453
 454 static int
 455 display_rc(const display *d, int strict)
 456 {
 457    return d->error_count + (strict ? d->warning_count : 0);
 458 }
 459
 460 /* libpng error and warning callbacks */
 461 PNG_FUNCTION(void, (PNGCBAPI error), (png_structp png_ptr, const char *message),
 462    static PNG_NORETURN)
 463 {
 464    display *d = (display*)png_get_error_ptr(png_ptr);
 465
 466    fprintf(stderr, "%s(%s): libpng error: %s\n", d->file, d->test, message);
 467    display_exit(d);
 468 }
 469
 470 static void PNGCBAPI
 471 warning(png_structp png_ptr, const char *message)
 472 {
 473    display *d = (display*)png_get_error_ptr(png_ptr);
 474
 475    fprintf(stderr, "%s(%s): libpng warning: %s\n", d->file, d->test, message);
 476    ++(d->warning_count);
 477 }
 478
 479 static png_uint_32
 480 get_valid(display *d, png_infop info_ptr)
 481 {
 482    png_uint_32 flags = png_get_valid(d->png_ptr, info_ptr, (png_uint_32)~0);
 483
 484    /* Map the text chunks back into the flags */
 485    {
 486       png_textp text;
 487       png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL);
 488
 489       while (ntext > 0) switch (text[--ntext].compression)
 490       {
 491          case -1:
 492             flags |= PNG_INFO_tEXt;
 493             break;
 494          case 0:
 495             flags |= PNG_INFO_zTXt;
 496             break;
 497          case 1:
 498          case 2:
 499             flags |= PNG_INFO_iTXt;
 500             break;
 501          default:
 502             fprintf(stderr, "%s(%s): unknown text compression %d\n", d->file,
 503                d->test, text[ntext].compression);
 504             display_exit(d);
 505       }
 506    }
 507
 508    return flags;
 509 }
 510
 511 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
 512 static int PNGCBAPI
 513 read_callback(png_structp pp, png_unknown_chunkp pc)
 514 {
 515    /* This function mimics the behavior of png_set_keep_unknown_chunks by
 516     * returning '0' to keep the chunk and '1' to discard it.
 517     */
 518    display *d = voidcast(display*, png_get_user_chunk_ptr(pp));
 519    int chunk = findb(pc->name);
 520    int keep, discard;
 521
 522    if (chunk < 0) /* not one in our list, so not a known chunk */
 523       keep = d->keep;
 524
 525    else
 526    {
 527       keep = chunk_info[chunk].keep;
 528       if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
 529       {
 530          /* See the comments in png.h - use the default for unknown chunks,
 531           * do not keep known chunks.
 532           */
 533          if (chunk_info[chunk].unknown)
 534             keep = d->keep;
 535
 536          else
 537             keep = PNG_HANDLE_CHUNK_NEVER;
 538       }
 539    }
 540
 541    switch (keep)
 542    {
 543       default:
 544          fprintf(stderr, "%s(%s): %d: unrecognized chunk option\n", d->file,
 545             d->test, chunk_info[chunk].keep);
 546          display_exit(d);
 547
 548       case PNG_HANDLE_CHUNK_AS_DEFAULT:
 549       case PNG_HANDLE_CHUNK_NEVER:
 550          discard = 1/*handled; discard*/;
 551          break;
 552
 553       case PNG_HANDLE_CHUNK_IF_SAFE:
 554       case PNG_HANDLE_CHUNK_ALWAYS:
 555          discard = 0/*not handled; keep*/;
 556          break;
 557    }
 558
 559    /* Also store information about this chunk in the display, the relevant flag
 560     * is set if the chunk is to be kept ('not handled'.)
 561     */
 562    if (chunk >= 0) if (!discard) /* stupidity to stop a GCC warning */
 563    {
 564       png_uint_32 flag = chunk_info[chunk].flag;
 565
 566       if (pc->location & PNG_AFTER_IDAT)
 567          d->after_IDAT |= flag;
 568
 569       else
 570          d->before_IDAT |= flag;
 571    }
 572
 573    /* However if there is no support to store unknown chunks don't ask libpng to
 574     * do it; there will be an png_error.
 575     */
 576 #  ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 577       return discard;
 578 #  else
 579       return 1; /*handled; discard*/
 580 #  endif
 581 }
 582 #endif /* READ_USER_CHUNKS_SUPPORTED */
 583
 584 #ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 585 static png_uint_32
 586 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 587 {
 588    /* Create corresponding 'unknown' flags */
 589    png_uint_32 flags = 0;
 590
 591    UNUSED(after_IDAT)
 592
 593    {
 594       png_unknown_chunkp unknown;
 595       int num_unknown = png_get_unknown_chunks(d->png_ptr, info_ptr, &unknown);
 596
 597       while (--num_unknown >= 0)
 598       {
 599          int chunk = findb(unknown[num_unknown].name);
 600
 601          /* Chunks not known to pngunknown must be validated here; since they
 602           * must also be unknown to libpng the 'display->keep' behavior should
 603           * have been used.
 604           */
 605          if (chunk < 0) switch (d->keep)
 606          {
 607             default: /* impossible */
 608             case PNG_HANDLE_CHUNK_AS_DEFAULT:
 609             case PNG_HANDLE_CHUNK_NEVER:
 610                fprintf(stderr, "%s(%s): %s: %s: unknown chunk saved\n",
 611                   d->file, d->test, d->keep ? "discard" : "default",
 612                   unknown[num_unknown].name);
 613                ++(d->error_count);
 614                break;
 615
 616             case PNG_HANDLE_CHUNK_IF_SAFE:
 617                if (!ancillaryb(unknown[num_unknown].name))
 618                {
 619                   fprintf(stderr,
 620                      "%s(%s): if-safe: %s: unknown critical chunk saved\n",
 621                      d->file, d->test, unknown[num_unknown].name);
 622                   ++(d->error_count);
 623                   break;
 624                }
 625                /* FALLTHROUGH */ /* (safe) */
 626             case PNG_HANDLE_CHUNK_ALWAYS:
 627                break;
 628          }
 629
 630          else
 631             flags |= chunk_info[chunk].flag;
 632       }
 633    }
 634
 635    return flags;
 636 }
 637 #else /* SAVE_UNKNOWN_CHUNKS */
 638 static png_uint_32
 639 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 640    /* Otherwise this will return the cached values set by any user callback */
 641 {
 642    UNUSED(info_ptr);
 643
 644    if (after_IDAT)
 645       return d->after_IDAT;
 646
 647    else
 648       return d->before_IDAT;
 649 }
 650
 651 #  ifndef PNG_READ_USER_CHUNKS_SUPPORTED
 652       /* The #defines above should mean this is never reached, it's just here as
 653        * a check to ensure the logic is correct.
 654        */
 655 #     error No store support and no user chunk support, this will not work
 656 #  endif /* READ_USER_CHUNKS */
 657 #endif /* SAVE_UNKNOWN_CHUNKS */
 658
 659 static int
 660 check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
 661    display *d, int set_callback)
 662 {
 663    int i, npasses, ipass;
 664    png_uint_32 height;
 665
 666    d->keep = PNG_HANDLE_CHUNK_AS_DEFAULT;
 667    d->before_IDAT = 0;
 668    d->after_IDAT = 0;
 669
 670    /* Some of these errors are permanently fatal and cause an exit here, others
 671     * are per-test and cause an error return.
 672     */
 673    d->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, d, error,
 674       warning);
 675    if (d->png_ptr == NULL)
 676    {
 677       fprintf(stderr, "%s(%s): could not allocate png struct\n", d->file,
 678          d->test);
 679       /* Terminate here, this error is not test specific. */
 680       exit(1);
 681    }
 682
 683    d->info_ptr = png_create_info_struct(d->png_ptr);
 684    d->end_ptr = png_create_info_struct(d->png_ptr);
 685    if (d->info_ptr == NULL || d->end_ptr == NULL)
 686    {
 687       fprintf(stderr, "%s(%s): could not allocate png info\n", d->file,
 688          d->test);
 689       clean_display(d);
 690       exit(1);
 691    }
 692
 693    png_init_io(d->png_ptr, fp);
 694
 695 #  ifdef PNG_READ_USER_CHUNKS_SUPPORTED
 696       /* This is only done if requested by the caller; it interferes with the
 697        * standard store/save mechanism.
 698        */
 699       if (set_callback)
 700          png_set_read_user_chunk_fn(d->png_ptr, d, read_callback);
 701 #  else
 702       UNUSED(set_callback)
 703 #  endif
 704
 705    /* Handle each argument in turn; multiple settings are possible for the same
 706     * chunk and multiple calls will occur (the last one should override all
 707     * preceding ones).
 708     */
 709    for (i=0; i<argc; ++i)
 710    {
 711       const char *equals = strchr(argv[i], '=');
 712
 713       if (equals != NULL)
 714       {
 715          int chunk, option;
 716
 717          if (strcmp(equals+1, "default") == 0)
 718             option = PNG_HANDLE_CHUNK_AS_DEFAULT;
 719          else if (strcmp(equals+1, "discard") == 0)
 720             option = PNG_HANDLE_CHUNK_NEVER;
 721          else if (strcmp(equals+1, "if-safe") == 0)
 722             option = PNG_HANDLE_CHUNK_IF_SAFE;
 723          else if (strcmp(equals+1, "save") == 0)
 724             option = PNG_HANDLE_CHUNK_ALWAYS;
 725          else
 726          {
 727             fprintf(stderr, "%s(%s): %s: unrecognized chunk option\n", d->file,
 728                d->test, argv[i]);
 729             display_exit(d);
 730          }
 731
 732          switch (equals - argv[i])
 733          {
 734             case 4: /* chunk name */
 735                chunk = find(argv[i]);
 736
 737                if (chunk >= 0)
 738                {
 739                   /* These #if tests have the effect of skipping the arguments
 740                    * if SAVE support is unavailable - we can't do a useful test
 741                    * in this case, so we just check the arguments!  This could
 742                    * be improved in the future by using the read callback.
 743                    */
 744 #                 if PNG_LIBPNG_VER >= 10700 &&\
 745                      !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
 746                      if (option < PNG_HANDLE_CHUNK_IF_SAFE)
 747 #                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
 748                   {
 749                      png_byte name[5];
 750
 751                      memcpy(name, chunk_info[chunk].name, 5);
 752                      png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
 753                      chunk_info[chunk].keep = option;
 754                   }
 755                   continue;
 756                }
 757
 758                break;
 759
 760             case 7: /* default */
 761                if (memcmp(argv[i], "default", 7) == 0)
 762                {
 763 #                 if PNG_LIBPNG_VER >= 10700 &&\
 764                      !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
 765                      if (option < PNG_HANDLE_CHUNK_IF_SAFE)
 766 #                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
 767                      png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
 768
 769                   d->keep = option;
 770                   continue;
 771                }
 772
 773                break;
 774
 775             case 3: /* all */
 776                if (memcmp(argv[i], "all", 3) == 0)
 777                {
 778 #                 if PNG_LIBPNG_VER >= 10700 &&\
 779                      !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
 780                      if (option < PNG_HANDLE_CHUNK_IF_SAFE)
 781 #                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
 782                      png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
 783
 784                   d->keep = option;
 785
 786                   for (chunk = 0; chunk < NINFO; ++chunk)
 787                      if (chunk_info[chunk].all)
 788                         chunk_info[chunk].keep = option;
 789                   continue;
 790                }
 791
 792                break;
 793
 794             default: /* some misplaced = */
 795
 796                break;
 797          }
 798       }
 799
 800       fprintf(stderr, "%s(%s): %s: unrecognized chunk argument\n", d->file,
 801          d->test, argv[i]);
 802       display_exit(d);
 803    }
 804
 805    png_read_info(d->png_ptr, d->info_ptr);
 806
 807    switch (png_get_interlace_type(d->png_ptr, d->info_ptr))
 808    {
 809       case PNG_INTERLACE_NONE:
 810          npasses = 1;
 811          break;
 812
 813       case PNG_INTERLACE_ADAM7:
 814          npasses = PNG_INTERLACE_ADAM7_PASSES;
 815          break;
 816
 817       default:
 818          /* Hard error because it is not test specific */
 819          fprintf(stderr, "%s(%s): invalid interlace type\n", d->file, d->test);
 820          clean_display(d);
 821          exit(1);
 822    }
 823
 824    /* Skip the image data, if IDAT is not being handled then don't do this
 825     * because it will cause a CRC error.
 826     */
 827    if (chunk_info[0/*IDAT*/].keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
 828    {
 829       png_start_read_image(d->png_ptr);
 830       height = png_get_image_height(d->png_ptr, d->info_ptr);
 831
 832       if (npasses > 1)
 833       {
 834          png_uint_32 width = png_get_image_width(d->png_ptr, d->info_ptr);
 835
 836          for (ipass=0; ipass<npasses; ++ipass)
 837          {
 838             png_uint_32 wPass = PNG_PASS_COLS(width, ipass);
 839
 840             if (wPass > 0)
 841             {
 842                png_uint_32 y;
 843
 844                for (y=0; y<height; ++y) if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
 845                   png_read_row(d->png_ptr, NULL, NULL);
 846             }
 847          }
 848       } /* interlaced */
 849
 850       else /* not interlaced */
 851       {
 852          png_uint_32 y;
 853
 854          for (y=0; y<height; ++y)
 855             png_read_row(d->png_ptr, NULL, NULL);
 856       }
 857    }
 858
 859    png_read_end(d->png_ptr, d->end_ptr);
 860
 861    flags[0] = get_valid(d, d->info_ptr);
 862    flags[1] = get_unknown(d, d->info_ptr, 0/*before IDAT*/);
 863
 864    /* Only png_read_png sets PNG_INFO_IDAT! */
 865    flags[chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT] |=
 866       PNG_INFO_IDAT;
 867
 868    flags[2] = get_valid(d, d->end_ptr);
 869    flags[3] = get_unknown(d, d->end_ptr, 1/*after IDAT*/);
 870
 871    clean_display(d);
 872
 873    return d->keep;
 874 }
 875
 876 static void
 877 check_error(display *d, png_uint_32 flags, const char *message)
 878 {
 879    while (flags)
 880    {
 881       png_uint_32 flag = flags & -(png_int_32)flags;
 882       int i = find_by_flag(flag);
 883
 884       fprintf(stderr, "%s(%s): chunk %s: %s\n", d->file, d->test,
 885          chunk_info[i].name, message);
 886       ++(d->error_count);
 887
 888       flags &= ~flag;
 889    }
 890 }
 891
 892 static void
 893 check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
 894    png_uint_32 unknown, const char *position, int set_callback)
 895 {
 896    while (chunks)
 897    {
 898       png_uint_32 flag = chunks & -(png_int_32)chunks;
 899       int i = find_by_flag(flag);
 900       int keep = chunk_info[i].keep;
 901       const char *type;
 902       const char *errorx = NULL;
 903
 904       if (chunk_info[i].unknown)
 905       {
 906          if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
 907          {
 908             type = "UNKNOWN (default)";
 909             keep = def;
 910          }
 911
 912          else
 913             type = "UNKNOWN (specified)";
 914
 915          if (flag & known)
 916             errorx = "chunk processed";
 917
 918          else switch (keep)
 919          {
 920             case PNG_HANDLE_CHUNK_AS_DEFAULT:
 921                if (flag & unknown)
 922                   errorx = "DEFAULT: unknown chunk saved";
 923                break;
 924
 925             case PNG_HANDLE_CHUNK_NEVER:
 926                if (flag & unknown)
 927                   errorx = "DISCARD: unknown chunk saved";
 928                break;
 929
 930             case PNG_HANDLE_CHUNK_IF_SAFE:
 931                if (ancillary(chunk_info[i].name))
 932                {
 933                   if (!(flag & unknown))
 934                      errorx = "IF-SAFE: unknown ancillary chunk lost";
 935                }
 936
 937                else if (flag & unknown)
 938                   errorx = "IF-SAFE: unknown critical chunk saved";
 939                break;
 940
 941             case PNG_HANDLE_CHUNK_ALWAYS:
 942                if (!(flag & unknown))
 943                   errorx = "SAVE: unknown chunk lost";
 944                break;
 945
 946             default:
 947                errorx = "internal error: bad keep";
 948                break;
 949          }
 950       } /* unknown chunk */
 951
 952       else /* known chunk */
 953       {
 954          type = "KNOWN";
 955
 956          if (flag & known)
 957          {
 958             /* chunk was processed, it won't have been saved because that is
 959              * caught below when checking for inconsistent processing.
 960              */
 961             if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
 962                errorx = "!DEFAULT: known chunk processed";
 963          }
 964
 965          else /* not processed */ switch (keep)
 966          {
 967             case PNG_HANDLE_CHUNK_AS_DEFAULT:
 968                errorx = "DEFAULT: known chunk not processed";
 969                break;
 970
 971             case PNG_HANDLE_CHUNK_NEVER:
 972                if (flag & unknown)
 973                   errorx = "DISCARD: known chunk saved";
 974                break;
 975
 976             case PNG_HANDLE_CHUNK_IF_SAFE:
 977                if (ancillary(chunk_info[i].name))
 978                {
 979                   if (!(flag & unknown))
 980                      errorx = "IF-SAFE: known ancillary chunk lost";
 981                }
 982
 983                else if (flag & unknown)
 984                   errorx = "IF-SAFE: known critical chunk saved";
 985                break;
 986
 987             case PNG_HANDLE_CHUNK_ALWAYS:
 988                if (!(flag & unknown))
 989                   errorx = "SAVE: known chunk lost";
 990                break;
 991
 992             default:
 993                errorx = "internal error: bad keep (2)";
 994                break;
 995          }
 996       }
 997
 998       if (errorx != NULL)
 999       {
1000          ++(d->error_count);
1001          fprintf(stderr, "%s(%s%s): %s %s %s: %s\n", d->file, d->test,
1002             set_callback ? ",callback" : "",
1003             type, chunk_info[i].name, position, errorx);
1004       }
1005
1006       chunks &= ~flag;
1007    }
1008 }
1009
1010 static void
1011 perform_one_test(FILE *fp, int argc, const char **argv,
1012    png_uint_32 *default_flags, display *d, int set_callback)
1013 {
1014    int def;
1015    png_uint_32 flags[2][4];
1016
1017    rewind(fp);
1018    clear_keep();
1019    memcpy(flags[0], default_flags, sizeof flags[0]);
1020
1021    def = check(fp, argc, argv, flags[1], d, set_callback);
1022
1023    /* If IDAT is being handled as unknown the image read is skipped and all the
1024     * IDATs after the first end up in the end info struct, so in this case add
1025     * IDAT to the list of unknowns.  (Do this after 'check' above sets the
1026     * chunk_info 'keep' fields.)
1027     *
1028     * Note that the flag setting has to be in the 'known' field to avoid
1029     * triggering the consistency check below and the flag must only be set if
1030     * there are multiple IDATs, so if the check above did find an unknown IDAT
1031     * after IDAT.
1032     */
1033    if (chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT &&
1034        (flags[1][3] & PNG_INFO_IDAT) != 0)
1035       flags[0][2] |= PNG_INFO_IDAT;
1036
1037    /* Chunks should either be known or unknown, never both and this should apply
1038     * whether the chunk is before or after the IDAT (actually, the app can
1039     * probably change this by swapping the handling after the image, but this
1040     * test does not do that.)
1041     */
1042    check_error(d, (flags[0][0]|flags[0][2]) & (flags[0][1]|flags[0][3]),
1043       "chunk handled inconsistently in count tests");
1044    check_error(d, (flags[1][0]|flags[1][2]) & (flags[1][1]|flags[1][3]),
1045       "chunk handled inconsistently in option tests");
1046
1047    /* Now find out what happened to each chunk before and after the IDAT and
1048     * determine if the behavior was correct.  First some basic sanity checks,
1049     * any known chunk should be known in the original count, any unknown chunk
1050     * should be either known or unknown in the original.
1051     */
1052    {
1053       png_uint_32 test;
1054
1055       test = flags[1][0] & ~flags[0][0];
1056       check_error(d, test, "new known chunk before IDAT");
1057       test = flags[1][1] & ~(flags[0][0] | flags[0][1]);
1058       check_error(d, test, "new unknown chunk before IDAT");
1059       test = flags[1][2] & ~flags[0][2];
1060       check_error(d, test, "new known chunk after IDAT");
1061       test = flags[1][3] & ~(flags[0][2] | flags[0][3]);
1062       check_error(d, test, "new unknown chunk after IDAT");
1063    }
1064
1065    /* Now each chunk in the original list should have been handled according to
1066     * the options set for that chunk, regardless of whether libpng knows about
1067     * it or not.
1068     */
1069    check_handling(d, def, flags[0][0] | flags[0][1], flags[1][0], flags[1][1],
1070       "before IDAT", set_callback);
1071    check_handling(d, def, flags[0][2] | flags[0][3], flags[1][2], flags[1][3],
1072       "after IDAT", set_callback);
1073 }
1074
1075 static void
1076 perform_one_test_safe(FILE *fp, int argc, const char **argv,
1077    png_uint_32 *default_flags, display *d, const char *test)
1078 {
1079    if (setjmp(d->error_return) == 0)
1080    {
1081       d->test = test; /* allow use of d->error_return */
1082 #     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1083          perform_one_test(fp, argc, argv, default_flags, d, 0);
1084 #     endif
1085 #     ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1086          perform_one_test(fp, argc, argv, default_flags, d, 1);
1087 #     endif
1088       d->test = init; /* prevent use of d->error_return */
1089    }
1090 }
1091
1092 static const char *standard_tests[] =
1093 {
1094  "discard", "default=discard", 0,
1095  "save", "default=save", 0,
1096  "if-safe", "default=if-safe", 0,
1097  "vpAg", "vpAg=if-safe", 0,
1098  "sTER", "sTER=if-safe", 0,
1099  "IDAT", "default=discard", "IDAT=save", 0,
1100  "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
1101    "sBIT=save", "sRGB=save", "eXIf=save", 0,
1102  0/*end*/
1103 };
1104
1105 static PNG_NORETURN void
1106 usage(const char *program, const char *reason)
1107 {
1108    fprintf(stderr, "pngunknown: %s: usage:\n %s [--strict] "
1109       "--default|{(CHNK|default|all)=(default|discard|if-safe|save)} "
1110       "testfile.png\n", reason, program);
1111    exit(99);
1112 }
1113
1114 int
1115 main(int argc, const char **argv)
1116 {
1117    FILE *fp;
1118    png_uint_32 default_flags[4/*valid,unknown{before,after}*/];
1119    int strict = 0, default_tests = 0;
1120    const char *count_argv = "default=save";
1121    const char *touch_file = NULL;
1122    display d;
1123
1124    init_display(&d, argv[0]);
1125
1126    while (++argv, --argc > 0)
1127    {
1128       if (strcmp(*argv, "--strict") == 0)
1129          strict = 1;
1130
1131       else if (strcmp(*argv, "--default") == 0)
1132          default_tests = 1;
1133
1134       else if (strcmp(*argv, "--touch") == 0)
1135       {
1136          if (argc > 1)
1137             touch_file = *++argv, --argc;
1138
1139          else
1140             usage(d.program, "--touch: missing file name");
1141       }
1142
1143       else
1144          break;
1145    }
1146
1147    /* A file name is required, but there should be no other arguments if
1148     * --default was specified.
1149     */
1150    if (argc <= 0)
1151       usage(d.program, "missing test file");
1152
1153    /* GCC BUG: if (default_tests && argc != 1) triggers some weird GCC argc
1154     * optimization which causes warnings with -Wstrict-overflow!
1155     */
1156    else if (default_tests) if (argc != 1)
1157       usage(d.program, "extra arguments");
1158
1159    /* The name of the test file is the last argument; remove it. */
1160    d.file = argv[--argc];
1161
1162    fp = fopen(d.file, "rb");
1163    if (fp == NULL)
1164    {
1165       perror(d.file);
1166       exit(99);
1167    }
1168
1169    /* First find all the chunks, known and unknown, in the test file, a failure
1170     * here aborts the whole test.
1171     *
1172     * If 'save' is supported then the normal saving method should happen,
1173     * otherwise if 'read' is supported then the read callback will do the
1174     * same thing.  If both are supported the 'read' callback won't be
1175     * instantiated by default.  If 'save' is *not* supported then a user
1176     * callback is required even though we can call png_get_unknown_chunks.
1177     */
1178    if (check(fp, 1, &count_argv, default_flags, &d,
1179 #     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1180          0
1181 #     else
1182          1
1183 #     endif
1184       ) != PNG_HANDLE_CHUNK_ALWAYS)
1185    {
1186       fprintf(stderr, "%s: %s: internal error\n", d.program, d.file);
1187       exit(99);
1188    }
1189
1190    /* Now find what the various supplied options cause to change: */
1191    if (!default_tests)
1192    {
1193       d.test = cmd; /* acts as a flag to say exit, do not longjmp */
1194 #     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1195          perform_one_test(fp, argc, argv, default_flags, &d, 0);
1196 #     endif
1197 #     ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1198          perform_one_test(fp, argc, argv, default_flags, &d, 1);
1199 #     endif
1200       d.test = init;
1201    }
1202
1203    else
1204    {
1205       const char **test = standard_tests;
1206
1207       /* Set the exit_test pointer here so we can continue after a libpng error.
1208        * NOTE: this leaks memory because the png_struct data from the failing
1209        * test is never freed.
1210        */
1211       while (*test)
1212       {
1213          const char *this_test = *test++;
1214          const char **next = test;
1215          int count = display_rc(&d, strict), new_count;
1216          const char *result;
1217          int arg_count = 0;
1218
1219          while (*next) ++next, ++arg_count;
1220
1221          perform_one_test_safe(fp, arg_count, test, default_flags, &d,
1222             this_test);
1223
1224          new_count = display_rc(&d, strict);
1225
1226          if (new_count == count)
1227             result = "PASS";
1228
1229          else
1230             result = "FAIL";
1231
1232          printf("%s: %s %s\n", result, d.program, this_test);
1233
1234          test = next+1;
1235       }
1236    }
1237
1238    fclose(fp);
1239
1240    if (display_rc(&d, strict) == 0)
1241    {
1242       /* Success, touch the success file if appropriate */
1243       if (touch_file != NULL)
1244       {
1245          FILE *fsuccess = fopen(touch_file, "wt");
1246
1247          if (fsuccess != NULL)
1248          {
1249             int err = 0;
1250             fprintf(fsuccess, "PNG unknown tests succeeded\n");
1251             fflush(fsuccess);
1252             err = ferror(fsuccess);
1253
1254             if (fclose(fsuccess) || err)
1255             {
1256                fprintf(stderr, "%s: write failed\n", touch_file);
1257                exit(99);
1258             }
1259          }
1260
1261          else
1262          {
1263             fprintf(stderr, "%s: open failed\n", touch_file);
1264             exit(99);
1265          }
1266       }
1267
1268       return 0;
1269    }
1270
1271    return 1;
1272 }
1273
1274 #else /* !(READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS) */
1275 int
1276 main(void)
1277 {
1278    fprintf(stderr,
1279       " test ignored: no support to find out about unknown chunks\n");
1280    /* So the test is skipped: */
1281    return SKIP;
1282 }
1283 #endif /* READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS */
1284
1285 #else /* !(SET_UNKNOWN_CHUNKS && READ) */
1286 int
1287 main(void)
1288 {
1289    fprintf(stderr,
1290       " test ignored: no support to modify unknown chunk handling\n");
1291    /* So the test is skipped: */
1292    return SKIP;
1293 }
1294 #endif /* SET_UNKNOWN_CHUNKS && READ*/