1 /* pngimage.c 2 * 3 * Copyright (c) 2014 John Cunningham Bowler 4 * 5 * Last changed in libpng 1.6.10 [March 6, 2014] 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 * Test the png_read_png and png_write_png interfaces. Given a PNG file load it 12 * using png_read_png and then write with png_write_png. Test all possible 13 * transforms. 14 */ 15 #include <stdarg.h> 16 #include <stdlib.h> 17 #include <string.h> 18 #include <errno.h> 19 #include <stdio.h> 20 #include <assert.h> 21 22 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H) 23 # include <config.h> 24 #endif 25 26 /* Define the following to use this test against your installed libpng, rather 27 * than the one being built here: 28 */ 29 #ifdef PNG_FREESTANDING_TESTS 30 # include <png.h> 31 #else 32 # include "../../png.h" 33 #endif 34 35 #ifndef PNG_SETJMP_SUPPORTED 36 # include <setjmp.h> /* because png.h did *not* include this */ 37 #endif 38 39 #if defined(PNG_INFO_IMAGE_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED) 40 /* If a transform is valid on both read and write this implies that if the 41 * transform is applied to read it must also be applied on write to produce 42 * meaningful data. This is because these transforms when performed on read 43 * produce data with a memory format that does not correspond to a PNG format. 44 * 45 * Most of these transforms are invertible; after applying the transform on 46 * write the result is the original PNG data that would have would have been 47 * read if no transform were applied. 48 * 49 * The exception is _SHIFT, which destroys the low order bits marked as not 50 * significant in a PNG with the sBIT chunk. 51 * 52 * The following table lists, for each transform, the conditions under which it 53 * is expected to do anything. Conditions are defined as follows: 54 * 55 * 1) Color mask bits required - simply a mask to AND with color_type; one of 56 * these must be present for the transform to fire, except that 0 means 57 * 'always'. 58 * 2) Color mask bits which must be absent - another mask - none of these must 59 * be present. 60 * 3) Bit depths - a mask of component bit depths for the transform to fire. 61 * 4) 'read' - the transform works in png_read_png. 62 * 5) 'write' - the transform works in png_write_png. 63 * 6) PNG_INFO_chunk; a mask of the chunks that must be present for the 64 * transform to fire. All must be present - the requirement is that 65 * png_get_valid() & mask == mask, so if mask is 0 there is no requirement. 66 * 67 * The condition refers to the original image state - if multiple transforms are 68 * used together it is possible to cause a transform that wouldn't fire on the 69 * original image to fire. 70 */ 71 static struct transform_info 72 { 73 const char *name; 74 int transform; 75 png_uint_32 valid_chunks; 76 # define CHUNK_NONE 0 77 # define CHUNK_sBIT PNG_INFO_sBIT 78 # define CHUNK_tRNS PNG_INFO_tRNS 79 png_byte color_mask_required; 80 png_byte color_mask_absent; 81 # define COLOR_MASK_X 0 82 # define COLOR_MASK_P PNG_COLOR_MASK_PALETTE 83 # define COLOR_MASK_C PNG_COLOR_MASK_COLOR 84 # define COLOR_MASK_A PNG_COLOR_MASK_ALPHA 85 # define COLOR_MASK_ALL (PALETTE+COLOR+ALPHA) /* absent = gray, no alpha */ 86 png_byte bit_depths; 87 # define BD_ALL (1 + 2 + 4 + 8 + 16) 88 # define BD_PAL (1 + 2 + 4 + 8) 89 # define BD_LOW (1 + 2 + 4) 90 # define BD_16 16 91 # define BD_TRUE (8+16) /* i.e. true-color depths */ 92 png_byte when; 93 # define TRANSFORM_R 1 94 # define TRANSFORM_W 2 95 # define TRANSFORM_RW 3 96 png_byte tested; /* the transform was tested somewhere */ 97 } transform_info[] = 98 { 99 /* List ALL the PNG_TRANSFORM_ macros here. Check for support using the READ 100 * macros; even if the transform is supported on write it cannot be tested 101 * without the read support. 102 */ 103 # define T(name,chunk,cm_required,cm_absent,bd,when)\ 104 { #name, PNG_TRANSFORM_ ## name, CHUNK_ ## chunk,\ 105 COLOR_MASK_ ## cm_required, COLOR_MASK_ ## cm_absent, BD_ ## bd,\ 106 TRANSFORM_ ## when, 0/*!tested*/ } 107 108 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED 109 T(STRIP_16, NONE, X, X, 16, R), 110 /* drops the bottom 8 bits when bit depth is 16 */ 111 #endif 112 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED 113 T(STRIP_ALPHA, NONE, A, X, ALL, R), 114 /* removes the alpha channel if present */ 115 #endif 116 #ifdef PNG_WRITE_PACK_SUPPORTED 117 # define TRANSFORM_RW_PACK TRANSFORM_RW 118 #else 119 # define TRANSFORM_RW_PACK TRANSFORM_R 120 #endif 121 #ifdef PNG_READ_PACK_SUPPORTED 122 T(PACKING, NONE, X, X, LOW, RW_PACK), 123 /* unpacks low-bit-depth components into 1 byte per component on read, 124 * reverses this on write. 125 */ 126 #endif 127 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED 128 # define TRANSFORM_RW_PACKSWAP TRANSFORM_RW 129 #else 130 # define TRANSFORM_RW_PACKSWAP TRANSFORM_R 131 #endif 132 #ifdef PNG_READ_PACKSWAP_SUPPORTED 133 T(PACKSWAP, NONE, X, X, LOW, RW_PACKSWAP), 134 /* reverses the order of low-bit-depth components packed into a byte */ 135 #endif 136 #ifdef PNG_READ_EXPAND_SUPPORTED 137 T(EXPAND, NONE, P, X, ALL, R), 138 /* expands PLTE PNG files to RGB (no tRNS) or RGBA (tRNS) * 139 * Note that the 'EXPAND' transform does lots of different things: */ 140 T(EXPAND, NONE, X, C, ALL, R), 141 /* expands grayscale PNG files to RGB, or RGBA */ 142 T(EXPAND, tRNS, X, A, ALL, R), 143 /* expands the tRNS chunk in files without alpha */ 144 #endif 145 #ifdef PNG_WRITE_INVERT_SUPPORTED 146 # define TRANSFORM_RW_INVERT TRANSFORM_RW 147 #else 148 # define TRANSFORM_RW_INVERT TRANSFORM_R 149 #endif 150 #ifdef PNG_READ_INVERT_SUPPORTED 151 T(INVERT_MONO, NONE, X, C, ALL, RW_INVERT), 152 /* converts gray-scale components to 1..0 from 0..1 */ 153 #endif 154 #ifdef PNG_WRITE_SHIFT_SUPPORTED 155 # define TRANSFORM_RW_SHIFT TRANSFORM_RW 156 #else 157 # define TRANSFORM_RW_SHIFT TRANSFORM_R 158 #endif 159 #ifdef PNG_READ_SHIFT_SUPPORTED 160 T(SHIFT, sBIT, X, X, ALL, RW_SHIFT), 161 /* reduces component values to the original range based on the sBIT chunk, 162 * this is only partially reversible - the low bits are lost and cannot be 163 * recovered on write. In fact write code replicates the bits to generate 164 * new low-order bits. 165 */ 166 #endif 167 #ifdef PNG_WRITE_BGR_SUPPORTED 168 # define TRANSFORM_RW_BGR TRANSFORM_RW 169 #else 170 # define TRANSFORM_RW_BGR TRANSFORM_R 171 #endif 172 #ifdef PNG_READ_BGR_SUPPORTED 173 T(BGR, NONE, C, P, TRUE, RW_BGR), 174 /* reverses the rgb component values of true-color pixels */ 175 #endif 176 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED 177 # define TRANSFORM_RW_SWAP_ALPHA TRANSFORM_RW 178 #else 179 # define TRANSFORM_RW_SWAP_ALPHA TRANSFORM_R 180 #endif 181 #ifdef PNG_READ_SWAP_ALPHA_SUPPORTED 182 T(SWAP_ALPHA, NONE, A, X, TRUE, RW_SWAP_ALPHA), 183 /* swaps the alpha channel of RGBA or GA pixels to the front - ARGB or 184 * AG, on write reverses the process. 185 */ 186 #endif 187 #ifdef PNG_WRITE_SWAP_SUPPORTED 188 # define TRANSFORM_RW_SWAP TRANSFORM_RW 189 #else 190 # define TRANSFORM_RW_SWAP TRANSFORM_R 191 #endif 192 #ifdef PNG_READ_SWAP_SUPPORTED 193 T(SWAP_ENDIAN, NONE, X, P, 16, RW_SWAP), 194 /* byte-swaps 16-bit component values */ 195 #endif 196 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED 197 # define TRANSFORM_RW_INVERT_ALPHA TRANSFORM_RW 198 #else 199 # define TRANSFORM_RW_INVERT_ALPHA TRANSFORM_R 200 #endif 201 #ifdef PNG_READ_INVERT_ALPHA_SUPPORTED 202 T(INVERT_ALPHA, NONE, A, X, TRUE, RW_INVERT_ALPHA), 203 /* converts an alpha channel from 0..1 to 1..0 */ 204 #endif 205 #ifdef PNG_WRITE_FILLER_SUPPORTED 206 T(STRIP_FILLER_BEFORE, NONE, A, P, TRUE, W), /* 'A' for a filler! */ 207 /* on write skips a leading filler channel; testing requires data with a 208 * filler channel so this is produced from RGBA or GA images by removing 209 * the 'alpha' flag from the color type in place. 210 */ 211 T(STRIP_FILLER_AFTER, NONE, A, P, TRUE, W), 212 /* on write strips a trailing filler channel */ 213 #endif 214 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED 215 T(GRAY_TO_RGB, NONE, X, C, ALL, R), 216 /* expands grayscale images to RGB, also causes the palette part of 217 * 'EXPAND' to happen. Low bit depth grayscale images are expanded to 218 * 8-bits per component and no attempt is made to convert the image to a 219 * palette image. While this transform is partially reversible 220 * png_write_png does not currently support this. 221 */ 222 T(GRAY_TO_RGB, NONE, P, X, ALL, R), 223 /* The 'palette' side effect mentioned above; a bit bogus but this is the 224 * way the libpng code works. 225 */ 226 #endif 227 #ifdef PNG_READ_EXPAND_16_SUPPORTED 228 T(EXPAND_16, NONE, X, X, PAL, R), 229 /* expands images to 16-bits per component, as a side effect expands 230 * palette images to RGB and expands the tRNS chunk if present, so it can 231 * modify 16-bit per component images as well: 232 */ 233 T(EXPAND_16, tRNS, X, A, 16, R), 234 /* side effect of EXPAND_16 - expands the tRNS chunk in an RGB or G 16-bit 235 * image. 236 */ 237 #endif 238 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED 239 T(SCALE_16, NONE, X, X, 16, R) 240 /* scales 16-bit components to 8-bits. */ 241 #endif 242 243 #undef T 244 }; 245 246 #define ARRAY_SIZE(a) ((sizeof a)/(sizeof a[0])) 247 #define TTABLE_SIZE ARRAY_SIZE(transform_info) 248 249 /* Some combinations of options that should be reversible are not; these cases 250 * are bugs. 251 */ 252 static int known_bad_combos[][2] = 253 { 254 /* problem, antidote */ 255 { PNG_TRANSFORM_SHIFT | PNG_TRANSFORM_INVERT_ALPHA, 0/*antidote*/ } 256 }; 257 258 static int 259 is_combo(int transforms) 260 { 261 return transforms & (transforms-1); /* non-zero if more than one set bit */ 262 } 263 264 static int 265 first_transform(int transforms) 266 { 267 return transforms & -transforms; /* lowest set bit */ 268 } 269 270 static int 271 is_bad_combo(int transforms) 272 { 273 unsigned int i; 274 275 for (i=0; i<ARRAY_SIZE(known_bad_combos); ++i) 276 { 277 int combo = known_bad_combos[i][0]; 278 279 if ((combo & transforms) == combo && 280 (transforms & known_bad_combos[i][1]) == 0) 281 return 1; 282 } 283 284 return 0; /* combo is ok */ 285 } 286 287 static const char * 288 transform_name(int t) 289 /* The name, if 't' has multiple bits set the name of the lowest set bit is 290 * returned. 291 */ 292 { 293 unsigned int i; 294 295 t &= -t; /* first set bit */ 296 297 for (i=0; i<TTABLE_SIZE; ++i) 298 { 299 if ((transform_info[i].transform & t) != 0) 300 return transform_info[i].name; 301 } 302 303 return "invalid transform"; 304 } 305 306 /* Variables calculated by validate_T below and used to record all the supported 307 * transforms. Need (unsigned int) here because of the places where these 308 * values are used (unsigned compares in the 'exhaustive' iterator.) 309 */ 310 static unsigned int read_transforms, write_transforms, rw_transforms; 311 312 static void 313 validate_T(void) 314 /* Validate the above table - this just builds the above values */ 315 { 316 unsigned int i; 317 318 for (i=0; i<TTABLE_SIZE; ++i) 319 { 320 if (transform_info[i].when & TRANSFORM_R) 321 read_transforms |= transform_info[i].transform; 322 323 if (transform_info[i].when & TRANSFORM_W) 324 write_transforms |= transform_info[i].transform; 325 } 326 327 /* Reversible transforms are those which are supported on both read and 328 * write. 329 */ 330 rw_transforms = read_transforms & write_transforms; 331 } 332 333 /* FILE DATA HANDLING 334 * The original file is cached in memory. During write the output file is 335 * written to memory. 336 * 337 * In both cases the file data is held in a linked list of buffers - not all 338 * of these are in use at any time. 339 */ 340 struct buffer_list 341 { 342 struct buffer_list *next; /* next buffer in list */ 343 png_byte buffer[1024]; /* the actual buffer */ 344 }; 345 346 struct buffer 347 { 348 struct buffer_list *last; /* last buffer in use */ 349 size_t end_count; /* bytes in the last buffer */ 350 struct buffer_list *current; /* current buffer being read */ 351 size_t read_count; /* count of bytes read from current */ 352 struct buffer_list first; /* the very first buffer */ 353 }; 354 355 static void 356 buffer_init(struct buffer *buffer) 357 /* Call this only once for a given buffer */ 358 { 359 buffer->first.next = NULL; 360 buffer->last = NULL; 361 buffer->current = NULL; 362 } 363 364 #ifdef PNG_WRITE_SUPPORTED 365 static void 366 buffer_start_write(struct buffer *buffer) 367 { 368 buffer->last = &buffer->first; 369 buffer->end_count = 0; 370 buffer->current = NULL; 371 } 372 #endif 373 374 static void 375 buffer_start_read(struct buffer *buffer) 376 { 377 buffer->current = &buffer->first; 378 buffer->read_count = 0; 379 } 380 381 #ifdef ENOMEM /* required by POSIX 1003.1 */ 382 # define MEMORY ENOMEM 383 #else 384 # define MEMORY ERANGE /* required by ANSI-C */ 385 #endif 386 static struct buffer * 387 get_buffer(png_structp pp) 388 /* Used from libpng callbacks to get the current buffer */ 389 { 390 return (struct buffer*)png_get_io_ptr(pp); 391 } 392 393 #define NEW(type) ((type *)malloc(sizeof (type))) 394 395 static struct buffer_list * 396 buffer_extend(struct buffer_list *current) 397 { 398 struct buffer_list *add; 399 400 assert(current->next == NULL); 401 402 add = NEW(struct buffer_list); 403 if (add == NULL) 404 return NULL; 405 406 add->next = NULL; 407 current->next = add; 408 409 return add; 410 } 411 412 /* Load a buffer from a file; does the equivalent of buffer_start_write. On a 413 * read error returns an errno value, else returns 0. 414 */ 415 static int 416 buffer_from_file(struct buffer *buffer, FILE *fp) 417 { 418 struct buffer_list *last = &buffer->first; 419 size_t count = 0; 420 421 for (;;) 422 { 423 size_t r = fread(last->buffer+count, 1/*size*/, 424 (sizeof last->buffer)-count, fp); 425 426 if (r > 0) 427 { 428 count += r; 429 430 if (count >= sizeof last->buffer) 431 { 432 assert(count == sizeof last->buffer); 433 count = 0; 434 435 if (last->next == NULL) 436 { 437 last = buffer_extend(last); 438 if (last == NULL) 439 return MEMORY; 440 } 441 442 else 443 last = last->next; 444 } 445 } 446 447 else /* fread failed - probably end of file */ 448 { 449 if (feof(fp)) 450 { 451 buffer->last = last; 452 buffer->end_count = count; 453 return 0; /* no error */ 454 } 455 456 /* Some kind of funky error; errno should be non-zero */ 457 return errno == 0 ? ERANGE : errno; 458 } 459 } 460 } 461 462 /* This structure is used to control the test of a single file. */ 463 typedef enum 464 { 465 VERBOSE, /* switches on all messages */ 466 INFORMATION, 467 WARNINGS, /* switches on warnings */ 468 LIBPNG_WARNING, 469 APP_WARNING, 470 ERRORS, /* just errors */ 471 APP_FAIL, /* continuable error - no need to longjmp */ 472 LIBPNG_ERROR, /* this and higher cause a longjmp */ 473 LIBPNG_BUG, /* erroneous behavior in libpng */ 474 APP_ERROR, /* such as out-of-memory in a callback */ 475 QUIET, /* no normal messages */ 476 USER_ERROR, /* such as file-not-found */ 477 INTERNAL_ERROR 478 } error_level; 479 #define LEVEL_MASK 0xf /* where the level is in 'options' */ 480 481 #define EXHAUSTIVE 0x010 /* Test all combinations of active options */ 482 #define STRICT 0x020 /* Fail on warnings as well as errors */ 483 #define LOG 0x040 /* Log pass/fail to stdout */ 484 #define CONTINUE 0x080 /* Continue on APP_FAIL errors */ 485 #define SKIP_BUGS 0x100 /* Skip over known bugs */ 486 #define LOG_SKIPPED 0x200 /* Log skipped bugs */ 487 #define FIND_BAD_COMBOS 0x400 /* Attempt to deduce bad combos */ 488 489 /* Result masks apply to the result bits in the 'results' field below; these 490 * bits are simple 1U<<error_level. A pass requires either nothing worse than 491 * warnings (--relaxes) or nothing worse than information (--strict) 492 */ 493 #define RESULT_STRICT(r) (((r) & ~((1U<<WARNINGS)-1)) == 0) 494 #define RESULT_RELAXED(r) (((r) & ~((1U<<ERRORS)-1)) == 0) 495 496 struct display 497 { 498 jmp_buf error_return; /* Where to go to on error */ 499 500 const char *filename; /* The name of the original file */ 501 const char *operation; /* Operation being performed */ 502 int transforms; /* Transform used in operation */ 503 png_uint_32 options; /* See display_log below */ 504 png_uint_32 results; /* A mask of errors seen */ 505 506 507 png_structp original_pp; /* used on the original read */ 508 png_infop original_ip; /* set by the original read */ 509 510 png_size_t original_rowbytes; /* of the original rows: */ 511 png_bytepp original_rows; /* from the original read */ 512 513 /* Original chunks valid */ 514 png_uint_32 chunks; 515 516 /* Original IHDR information */ 517 png_uint_32 width; 518 png_uint_32 height; 519 int bit_depth; 520 int color_type; 521 int interlace_method; 522 int compression_method; 523 int filter_method; 524 525 /* Derived information for the original image. */ 526 int active_transforms; /* transforms that do something on read */ 527 int ignored_transforms; /* transforms that should do nothing */ 528 529 /* Used on a read, both the original read and when validating a written 530 * image. 531 */ 532 png_structp read_pp; 533 png_infop read_ip; 534 535 # ifdef PNG_WRITE_SUPPORTED 536 /* Used to write a new image (the original info_ptr is used) */ 537 png_structp write_pp; 538 struct buffer written_file; /* where the file gets written */ 539 # endif 540 541 struct buffer original_file; /* Data read from the original file */ 542 }; 543 544 static void 545 display_init(struct display *dp) 546 /* Call this only once right at the start to initialize the control 547 * structure, the (struct buffer) lists are maintained across calls - the 548 * memory is not freed. 549 */ 550 { 551 memset(dp, 0, sizeof *dp); 552 dp->options = WARNINGS; /* default to !verbose, !quiet */ 553 dp->filename = NULL; 554 dp->operation = NULL; 555 dp->original_pp = NULL; 556 dp->original_ip = NULL; 557 dp->original_rows = NULL; 558 dp->read_pp = NULL; 559 dp->read_ip = NULL; 560 buffer_init(&dp->original_file); 561 562 # ifdef PNG_WRITE_SUPPORTED 563 dp->write_pp = NULL; 564 buffer_init(&dp->written_file); 565 # endif 566 } 567 568 static void 569 display_clean_read(struct display *dp) 570 { 571 if (dp->read_pp != NULL) 572 png_destroy_read_struct(&dp->read_pp, &dp->read_ip, NULL); 573 } 574 575 #ifdef PNG_WRITE_SUPPORTED 576 static void 577 display_clean_write(struct display *dp) 578 { 579 if (dp->write_pp != NULL) 580 png_destroy_write_struct(&dp->write_pp, NULL); 581 } 582 #endif 583 584 static void 585 display_clean(struct display *dp) 586 { 587 # ifdef PNG_WRITE_SUPPORTED 588 display_clean_write(dp); 589 # endif 590 display_clean_read(dp); 591 592 dp->original_rowbytes = 0; 593 dp->original_rows = NULL; 594 dp->chunks = 0; 595 596 png_destroy_read_struct(&dp->original_pp, &dp->original_ip, NULL); 597 /* leave the filename for error detection */ 598 dp->results = 0; /* reset for next time */ 599 } 600 601 static struct display * 602 get_dp(png_structp pp) 603 /* The display pointer is always stored in the png_struct error pointer */ 604 { 605 struct display *dp = (struct display*)png_get_error_ptr(pp); 606 607 if (dp == NULL) 608 { 609 fprintf(stderr, "pngimage: internal error (no display)\n"); 610 exit(99); /* prevents a crash */ 611 } 612 613 return dp; 614 } 615 616 /* error handling */ 617 #ifdef __GNUC__ 618 # define VGATTR __attribute__((__format__ (__printf__,3,4))) 619 /* Required to quiet GNUC warnings when the compiler sees a stdarg function 620 * that calls one of the stdio v APIs. 621 */ 622 #else 623 # define VGATTR 624 #endif 625 static void VGATTR 626 display_log(struct display *dp, error_level level, const char *fmt, ...) 627 /* 'level' is as above, fmt is a stdio style format string. This routine 628 * does not return if level is above LIBPNG_WARNING 629 */ 630 { 631 dp->results |= 1U << level; 632 633 if (level > (error_level)(dp->options & LEVEL_MASK)) 634 { 635 const char *lp; 636 va_list ap; 637 638 switch (level) 639 { 640 case INFORMATION: lp = "information"; break; 641 case LIBPNG_WARNING: lp = "warning(libpng)"; break; 642 case APP_WARNING: lp = "warning(pngimage)"; break; 643 case APP_FAIL: lp = "error(continuable)"; break; 644 case LIBPNG_ERROR: lp = "error(libpng)"; break; 645 case LIBPNG_BUG: lp = "bug(libpng)"; break; 646 case APP_ERROR: lp = "error(pngimage)"; break; 647 case USER_ERROR: lp = "error(user)"; break; 648 649 case INTERNAL_ERROR: /* anything unexpected is an internal error: */ 650 case VERBOSE: case WARNINGS: case ERRORS: case QUIET: 651 default: lp = "bug(pngimage)"; break; 652 } 653 654 fprintf(stderr, "%s: %s: %s", 655 dp->filename != NULL ? dp->filename : "<stdin>", lp, dp->operation); 656 657 if (dp->transforms != 0) 658 { 659 int tr = dp->transforms; 660 661 if (is_combo(tr)) 662 fprintf(stderr, "(0x%x)", tr); 663 664 else 665 fprintf(stderr, "(%s)", transform_name(tr)); 666 } 667 668 fprintf(stderr, ": "); 669 670 va_start(ap, fmt); 671 vfprintf(stderr, fmt, ap); 672 va_end(ap); 673 674 fputc('\n', stderr); 675 } 676 /* else do not output any message */ 677 678 /* Errors cause this routine to exit to the fail code */ 679 if (level > APP_FAIL || (level > ERRORS && !(dp->options & CONTINUE))) 680 longjmp(dp->error_return, level); 681 } 682 683 /* error handler callbacks for libpng */ 684 static void PNGCBAPI 685 display_warning(png_structp pp, png_const_charp warning) 686 { 687 display_log(get_dp(pp), LIBPNG_WARNING, "%s", warning); 688 } 689 690 static void PNGCBAPI 691 display_error(png_structp pp, png_const_charp error) 692 { 693 struct display *dp = get_dp(pp); 694 695 display_log(dp, LIBPNG_ERROR, "%s", error); 696 } 697 698 static void 699 display_cache_file(struct display *dp, const char *filename) 700 /* Does the initial cache of the file. */ 701 { 702 FILE *fp; 703 int ret; 704 705 dp->filename = filename; 706 707 if (filename != NULL) 708 { 709 fp = fopen(filename, "rb"); 710 if (fp == NULL) 711 display_log(dp, USER_ERROR, "open failed: %s", strerror(errno)); 712 } 713 714 else 715 fp = stdin; 716 717 ret = buffer_from_file(&dp->original_file, fp); 718 719 fclose(fp); 720 721 if (ret != 0) 722 display_log(dp, APP_ERROR, "read failed: %s", strerror(ret)); 723 } 724 725 static void 726 buffer_read(struct display *dp, struct buffer *bp, png_bytep data, 727 png_size_t size) 728 { 729 struct buffer_list *last = bp->current; 730 size_t read_count = bp->read_count; 731 732 while (size > 0) 733 { 734 size_t avail; 735 736 if (last == NULL || 737 (last == bp->last && read_count >= bp->end_count)) 738 { 739 display_log(dp, USER_ERROR, "file truncated (%lu bytes)", 740 (unsigned long)size); 741 /*NOTREACHED*/ 742 break; 743 } 744 745 else if (read_count >= sizeof last->buffer) 746 { 747 /* Move to the next buffer: */ 748 last = last->next; 749 read_count = 0; 750 bp->current = last; /* Avoid update outside the loop */ 751 752 /* And do a sanity check (the EOF case is caught above) */ 753 if (last == NULL) 754 { 755 display_log(dp, INTERNAL_ERROR, "damaged buffer list"); 756 /*NOTREACHED*/ 757 break; 758 } 759 } 760 761 avail = (sizeof last->buffer) - read_count; 762 if (avail > size) 763 avail = size; 764 765 memcpy(data, last->buffer + read_count, avail); 766 read_count += avail; 767 size -= avail; 768 data += avail; 769 } 770 771 bp->read_count = read_count; 772 } 773 774 static void PNGCBAPI 775 read_function(png_structp pp, png_bytep data, png_size_t size) 776 { 777 buffer_read(get_dp(pp), get_buffer(pp), data, size); 778 } 779 780 static void 781 read_png(struct display *dp, struct buffer *bp, const char *operation, 782 int transforms) 783 { 784 png_structp pp; 785 png_infop ip; 786 787 /* This cleans out any previous read and sets operation and transforms to 788 * empty. 789 */ 790 display_clean_read(dp); 791 792 if (operation != NULL) /* else this is a verify and do not overwrite info */ 793 { 794 dp->operation = operation; 795 dp->transforms = transforms; 796 } 797 798 dp->read_pp = pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, dp, 799 display_error, display_warning); 800 if (pp == NULL) 801 display_log(dp, LIBPNG_ERROR, "failed to create read struct"); 802 803 /* The png_read_png API requires us to make the info struct, but it does the 804 * call to png_read_info. 805 */ 806 dp->read_ip = ip = png_create_info_struct(pp); 807 if (ip == NULL) 808 display_log(dp, LIBPNG_ERROR, "failed to create info struct"); 809 810 # ifdef PNG_SET_USER_LIMITS_SUPPORTED 811 /* Remove the user limits, if any */ 812 png_set_user_limits(pp, 0x7fffffff, 0x7fffffff); 813 # endif 814 815 /* Set the IO handling */ 816 buffer_start_read(bp); 817 png_set_read_fn(pp, bp, read_function); 818 819 png_read_png(pp, ip, transforms, NULL/*params*/); 820 821 #if 0 /* crazy debugging */ 822 { 823 png_bytep pr = png_get_rows(pp, ip)[0]; 824 size_t rb = png_get_rowbytes(pp, ip); 825 size_t cb; 826 char c = ' '; 827 828 fprintf(stderr, "%.4x %2d (%3lu bytes):", transforms, png_get_bit_depth(pp,ip), (unsigned long)rb); 829 830 for (cb=0; cb<rb; ++cb) 831 fputc(c, stderr), fprintf(stderr, "%.2x", pr[cb]), c='.'; 832 833 fputc('\n', stderr); 834 } 835 #endif 836 } 837 838 static void 839 update_display(struct display *dp) 840 /* called once after the first read to update all the info, original_pp and 841 * original_ip must have been filled in. 842 */ 843 { 844 png_structp pp; 845 png_infop ip; 846 847 /* Now perform the initial read with a 0 tranform. */ 848 read_png(dp, &dp->original_file, "original read", 0/*no transform*/); 849 850 /* Move the result to the 'original' fields */ 851 dp->original_pp = pp = dp->read_pp, dp->read_pp = NULL; 852 dp->original_ip = ip = dp->read_ip, dp->read_ip = NULL; 853 854 dp->original_rowbytes = png_get_rowbytes(pp, ip); 855 if (dp->original_rowbytes == 0) 856 display_log(dp, LIBPNG_BUG, "png_get_rowbytes returned 0"); 857 858 dp->chunks = png_get_valid(pp, ip, 0xffffffff); 859 if ((dp->chunks & PNG_INFO_IDAT) == 0) /* set by png_read_png */ 860 display_log(dp, LIBPNG_BUG, "png_read_png did not set IDAT flag"); 861 862 dp->original_rows = png_get_rows(pp, ip); 863 if (dp->original_rows == NULL) 864 display_log(dp, LIBPNG_BUG, "png_read_png did not create row buffers"); 865 866 if (!png_get_IHDR(pp, ip, 867 &dp->width, &dp->height, &dp->bit_depth, &dp->color_type, 868 &dp->interlace_method, &dp->compression_method, &dp->filter_method)) 869 display_log(dp, LIBPNG_BUG, "png_get_IHDR failed"); 870 871 /* 'active' transforms are discovered based on the original image format; 872 * running one active transform can activate others. At present the code 873 * does not attempt to determine the closure. 874 */ 875 { 876 png_uint_32 chunks = dp->chunks; 877 int active = 0, inactive = 0; 878 int ct = dp->color_type; 879 int bd = dp->bit_depth; 880 unsigned int i; 881 882 for (i=0; i<TTABLE_SIZE; ++i) 883 { 884 int transform = transform_info[i].transform; 885 886 if ((transform_info[i].valid_chunks == 0 || 887 (transform_info[i].valid_chunks & chunks) != 0) && 888 (transform_info[i].color_mask_required & ct) == 889 transform_info[i].color_mask_required && 890 (transform_info[i].color_mask_absent & ct) == 0 && 891 (transform_info[i].bit_depths & bd) != 0 && 892 (transform_info[i].when & TRANSFORM_R) != 0) 893 active |= transform; 894 895 else if ((transform_info[i].when & TRANSFORM_R) != 0) 896 inactive |= transform; 897 } 898 899 /* Some transforms appear multiple times in the table; the 'active' status 900 * is the logical OR of these and the inactive status must be adjusted to 901 * take this into account. 902 */ 903 inactive &= ~active; 904 905 dp->active_transforms = active; 906 dp->ignored_transforms = inactive; /* excluding write-only transforms */ 907 908 if (active == 0) 909 display_log(dp, INTERNAL_ERROR, "bad transform table"); 910 } 911 } 912 913 static int 914 compare_read(struct display *dp, int applied_transforms) 915 { 916 /* Compare the png_info from read_ip with original_info */ 917 size_t rowbytes; 918 png_uint_32 width, height; 919 int bit_depth, color_type; 920 int interlace_method, compression_method, filter_method; 921 const char *e = NULL; 922 923 png_get_IHDR(dp->read_pp, dp->read_ip, &width, &height, &bit_depth, 924 &color_type, &interlace_method, &compression_method, &filter_method); 925 926 # define C(item) if (item != dp->item) \ 927 display_log(dp, APP_WARNING, "IHDR " #item "(%lu) changed to %lu",\ 928 (unsigned long)dp->item, (unsigned long)item), e = #item 929 930 /* The IHDR should be identical: */ 931 C(width); 932 C(height); 933 C(bit_depth); 934 C(color_type); 935 C(interlace_method); 936 C(compression_method); 937 C(filter_method); 938 939 /* 'e' remains set to the name of the last thing changed: */ 940 if (e) 941 display_log(dp, APP_ERROR, "IHDR changed (%s)", e); 942 943 /* All the chunks from the original PNG should be preserved in the output PNG 944 * because the PNG format has not been changed. 945 */ 946 { 947 unsigned long chunks = 948 png_get_valid(dp->read_pp, dp->read_ip, 0xffffffff); 949 950 if (chunks != dp->chunks) 951 display_log(dp, APP_FAIL, "PNG chunks changed from 0x%lx to 0x%lx", 952 (unsigned long)dp->chunks, chunks); 953 } 954 955 /* rowbytes should be the same */ 956 rowbytes = png_get_rowbytes(dp->read_pp, dp->read_ip); 957 958 /* NOTE: on 64-bit systems this may trash the top bits of rowbytes, 959 * which could lead to weird error messages. 960 */ 961 if (rowbytes != dp->original_rowbytes) 962 display_log(dp, APP_ERROR, "PNG rowbytes changed from %lu to %lu", 963 (unsigned long)dp->original_rowbytes, (unsigned long)rowbytes); 964 965 /* The rows should be the same too, unless the applied transforms includes 966 * the shift transform, in which case low bits may have been lost. 967 */ 968 { 969 png_bytepp rows = png_get_rows(dp->read_pp, dp->read_ip); 970 unsigned int mask; /* mask (if not zero) for the final byte */ 971 972 if (bit_depth < 8) 973 { 974 /* Need the stray bits at the end, this depends only on the low bits 975 * of the image width; overflow does not matter. If the width is an 976 * exact multiple of 8 bits this gives a mask of 0, not 0xff. 977 */ 978 mask = 0xff & (0xff00 >> ((bit_depth * width) & 7)); 979 } 980 981 else 982 mask = 0; 983 984 if (rows == NULL) 985 display_log(dp, LIBPNG_BUG, "png_get_rows returned NULL"); 986 987 if ((applied_transforms & PNG_TRANSFORM_SHIFT) == 0 || 988 (dp->active_transforms & PNG_TRANSFORM_SHIFT) == 0 || 989 color_type == PNG_COLOR_TYPE_PALETTE) 990 { 991 unsigned long y; 992 993 for (y=0; y<height; ++y) 994 { 995 png_bytep row = rows[y]; 996 png_bytep orig = dp->original_rows[y]; 997 998 if (memcmp(row, orig, rowbytes-(mask != 0)) != 0 || (mask != 0 && 999 ((row[rowbytes-1] & mask) != (orig[rowbytes-1] & mask)))) 1000 { 1001 size_t x; 1002 1003 /* Find the first error */ 1004 for (x=0; x<rowbytes-1; ++x) if (row[x] != orig[x]) 1005 break; 1006 1007 display_log(dp, APP_FAIL, 1008 "byte(%lu,%lu) changed 0x%.2x -> 0x%.2x", 1009 (unsigned long)x, (unsigned long)y, orig[x], row[x]); 1010 return 0; /* don't keep reporting failed rows on 'continue' */ 1011 } 1012 } 1013 } 1014 1015 else 1016 { 1017 unsigned long y; 1018 int bpp; /* bits-per-pixel then bytes-per-pixel */ 1019 /* components are up to 8 bytes in size */ 1020 png_byte sig_bits[8]; 1021 png_color_8p sBIT; 1022 1023 if (png_get_sBIT(dp->read_pp, dp->read_ip, &sBIT) != PNG_INFO_sBIT) 1024 display_log(dp, INTERNAL_ERROR, 1025 "active shift transform but no sBIT in file"); 1026 1027 switch (color_type) 1028 { 1029 case PNG_COLOR_TYPE_GRAY: 1030 sig_bits[0] = sBIT->gray; 1031 bpp = bit_depth; 1032 break; 1033 1034 case PNG_COLOR_TYPE_GA: 1035 sig_bits[0] = sBIT->gray; 1036 sig_bits[1] = sBIT->alpha; 1037 bpp = 2 * bit_depth; 1038 break; 1039 1040 case PNG_COLOR_TYPE_RGB: 1041 sig_bits[0] = sBIT->red; 1042 sig_bits[1] = sBIT->green; 1043 sig_bits[2] = sBIT->blue; 1044 bpp = 3 * bit_depth; 1045 break; 1046 1047 case PNG_COLOR_TYPE_RGBA: 1048 sig_bits[0] = sBIT->red; 1049 sig_bits[1] = sBIT->green; 1050 sig_bits[2] = sBIT->blue; 1051 sig_bits[3] = sBIT->alpha; 1052 bpp = 4 * bit_depth; 1053 break; 1054 1055 default: 1056 display_log(dp, LIBPNG_ERROR, "invalid colour type %d", 1057 color_type); 1058 /*NOTREACHED*/ 1059 bpp = 0; 1060 break; 1061 } 1062 1063 { 1064 int b; 1065 1066 for (b=0; 8*b<bpp; ++b) 1067 { 1068 /* libpng should catch this; if not there is a security issue 1069 * because an app (like this one) may overflow an array. In fact 1070 * libpng doesn't catch this at present. 1071 */ 1072 if (sig_bits[b] == 0 || sig_bits[b] > bit_depth/*!palette*/) 1073 display_log(dp, LIBPNG_BUG, 1074 "invalid sBIT[%u] value %d returned for PNG bit depth %d", 1075 b, sig_bits[b], bit_depth); 1076 } 1077 } 1078 1079 if (bpp < 8 && bpp != bit_depth) 1080 { 1081 /* sanity check; this is a grayscale PNG; something is wrong in the 1082 * code above. 1083 */ 1084 display_log(dp, INTERNAL_ERROR, "invalid bpp %u for bit_depth %u", 1085 bpp, bit_depth); 1086 } 1087 1088 switch (bit_depth) 1089 { 1090 int b; 1091 1092 case 16: /* Two bytes per component, bit-endian */ 1093 for (b = (bpp >> 4); b > 0; ) 1094 { 1095 unsigned int sig = (unsigned int)(0xffff0000 >> sig_bits[b]); 1096 1097 sig_bits[2*b+1] = (png_byte)sig; 1098 sig_bits[2*b+0] = (png_byte)(sig >> 8); /* big-endian */ 1099 } 1100 break; 1101 1102 case 8: /* One byte per component */ 1103 for (b=0; b*8 < bpp; ++b) 1104 sig_bits[b] = (png_byte)(0xff00 >> sig_bits[b]); 1105 break; 1106 1107 case 1: /* allowed, but dumb */ 1108 /* Value is 1 */ 1109 sig_bits[0] = 0xff; 1110 break; 1111 1112 case 2: /* Replicate 4 times */ 1113 /* Value is 1 or 2 */ 1114 b = 0x3 & ((0x3<<2) >> sig_bits[0]); 1115 b |= b << 2; 1116 b |= b << 4; 1117 sig_bits[0] = (png_byte)b; 1118 break; 1119 1120 case 4: /* Relicate twice */ 1121 /* Value is 1, 2, 3 or 4 */ 1122 b = 0xf & ((0xf << 4) >> sig_bits[0]); 1123 b |= b << 4; 1124 sig_bits[0] = (png_byte)b; 1125 break; 1126 1127 default: 1128 display_log(dp, LIBPNG_BUG, "invalid bit depth %d", bit_depth); 1129 break; 1130 } 1131 1132 /* Convert bpp to bytes; this gives '1' for low-bit depth grayscale, 1133 * where there are multiple pixels per byte. 1134 */ 1135 bpp = (bpp+7) >> 3; 1136 1137 /* The mask can be combined with sig_bits[0] */ 1138 if (mask != 0) 1139 { 1140 mask &= sig_bits[0]; 1141 1142 if (bpp != 1 || mask == 0) 1143 display_log(dp, INTERNAL_ERROR, "mask calculation error %u, %u", 1144 bpp, mask); 1145 } 1146 1147 for (y=0; y<height; ++y) 1148 { 1149 png_bytep row = rows[y]; 1150 png_bytep orig = dp->original_rows[y]; 1151 unsigned long x; 1152 1153 for (x=0; x<(width-(mask!=0)); ++x) 1154 { 1155 int b; 1156 1157 for (b=0; b<bpp; ++b) 1158 { 1159 if ((*row++ & sig_bits[b]) != (*orig++ & sig_bits[b])) 1160 { 1161 display_log(dp, APP_FAIL, 1162 "significant bits at (%lu[%u],%lu) changed %.2x->%.2x", 1163 x, b, y, orig[-1], row[-1]); 1164 return 0; 1165 } 1166 } 1167 } 1168 1169 if (mask != 0 && (*row & mask) != (*orig & mask)) 1170 { 1171 display_log(dp, APP_FAIL, 1172 "significant bits at (%lu[end],%lu) changed", x, y); 1173 return 0; 1174 } 1175 } /* for y */ 1176 } 1177 } 1178 1179 return 1; /* compare succeeded */ 1180 } 1181 1182 #ifdef PNG_WRITE_SUPPORTED 1183 static void 1184 buffer_write(struct display *dp, struct buffer *buffer, png_bytep data, 1185 png_size_t size) 1186 /* Generic write function used both from the write callback provided to 1187 * libpng and from the generic read code. 1188 */ 1189 { 1190 /* Write the data into the buffer, adding buffers as required */ 1191 struct buffer_list *last = buffer->last; 1192 size_t end_count = buffer->end_count; 1193 1194 while (size > 0) 1195 { 1196 size_t avail; 1197 1198 if (end_count >= sizeof last->buffer) 1199 { 1200 if (last->next == NULL) 1201 { 1202 last = buffer_extend(last); 1203 1204 if (last == NULL) 1205 display_log(dp, APP_ERROR, "out of memory saving file"); 1206 } 1207 1208 else 1209 last = last->next; 1210 1211 buffer->last = last; /* avoid the need to rewrite every time */ 1212 end_count = 0; 1213 } 1214 1215 avail = (sizeof last->buffer) - end_count; 1216 if (avail > size) 1217 avail = size; 1218 1219 memcpy(last->buffer + end_count, data, avail); 1220 end_count += avail; 1221 size -= avail; 1222 data += avail; 1223 } 1224 1225 buffer->end_count = end_count; 1226 } 1227 1228 static void PNGCBAPI 1229 write_function(png_structp pp, png_bytep data, png_size_t size) 1230 { 1231 buffer_write(get_dp(pp), get_buffer(pp), data, size); 1232 } 1233 1234 static void 1235 write_png(struct display *dp, png_infop ip, int transforms) 1236 { 1237 display_clean_write(dp); /* safety */ 1238 1239 buffer_start_write(&dp->written_file); 1240 dp->operation = "write"; 1241 dp->transforms = transforms; 1242 1243 dp->write_pp = png_create_write_struct(PNG_LIBPNG_VER_STRING, dp, 1244 display_error, display_warning); 1245 1246 if (dp->write_pp == NULL) 1247 display_log(dp, APP_ERROR, "failed to create write png_struct"); 1248 1249 png_set_write_fn(dp->write_pp, &dp->written_file, write_function, 1250 NULL/*flush*/); 1251 1252 # ifdef PNG_SET_USER_LIMITS_SUPPORTED 1253 /* Remove the user limits, if any */ 1254 png_set_user_limits(dp->write_pp, 0x7fffffff, 0x7fffffff); 1255 # endif 1256 1257 /* Certain transforms require the png_info to be zapped to allow the 1258 * transform to work correctly. 1259 */ 1260 if (transforms & (PNG_TRANSFORM_PACKING| 1261 PNG_TRANSFORM_STRIP_FILLER| 1262 PNG_TRANSFORM_STRIP_FILLER_BEFORE)) 1263 { 1264 int ct = dp->color_type; 1265 1266 if (transforms & (PNG_TRANSFORM_STRIP_FILLER| 1267 PNG_TRANSFORM_STRIP_FILLER_BEFORE)) 1268 ct &= ~PNG_COLOR_MASK_ALPHA; 1269 1270 png_set_IHDR(dp->write_pp, ip, dp->width, dp->height, dp->bit_depth, ct, 1271 dp->interlace_method, dp->compression_method, dp->filter_method); 1272 } 1273 1274 png_write_png(dp->write_pp, ip, transforms, NULL/*params*/); 1275 1276 /* Clean it on the way out - if control returns to the caller then the 1277 * written_file contains the required data. 1278 */ 1279 display_clean_write(dp); 1280 } 1281 #endif /* WRITE_SUPPORTED */ 1282 1283 static int 1284 skip_transform(struct display *dp, int tr) 1285 /* Helper to test for a bad combo and log it if it is skipped */ 1286 { 1287 if ((dp->options & SKIP_BUGS) != 0 && is_bad_combo(tr)) 1288 { 1289 /* Log this to stdout if logging is on, otherwise just do an information 1290 * display_log. 1291 */ 1292 if ((dp->options & LOG_SKIPPED) != 0) 1293 { 1294 printf("SKIP: %s transforms ", dp->filename); 1295 1296 while (tr != 0) 1297 { 1298 int next = first_transform(tr); 1299 tr &= ~next; 1300 1301 printf("%s", transform_name(next)); 1302 if (tr != 0) 1303 putchar('+'); 1304 } 1305 1306 putchar('\n'); 1307 } 1308 1309 else 1310 display_log(dp, INFORMATION, "%s: skipped known bad combo 0x%x", 1311 dp->filename, tr); 1312 1313 return 1; /* skip */ 1314 } 1315 1316 return 0; /* don't skip */ 1317 } 1318 1319 static void 1320 test_one_file(struct display *dp, const char *filename) 1321 { 1322 /* First cache the file and update the display original file 1323 * information for the new file. 1324 */ 1325 dp->operation = "cache file"; 1326 dp->transforms = 0; 1327 display_cache_file(dp, filename); 1328 update_display(dp); 1329 1330 /* First test: if there are options that should be ignored for this file 1331 * verify that they really are ignored. 1332 */ 1333 if (dp->ignored_transforms != 0) 1334 { 1335 read_png(dp, &dp->original_file, "ignored transforms", 1336 dp->ignored_transforms); 1337 1338 /* The result should be identical to the original_rows */ 1339 if (!compare_read(dp, 0/*transforms applied*/)) 1340 return; /* no point testing more */ 1341 } 1342 1343 #ifdef PNG_WRITE_SUPPORTED 1344 /* Second test: write the original PNG data out to a new file (to test the 1345 * write side) then read the result back in and make sure that it hasn't 1346 * changed. 1347 */ 1348 dp->operation = "write"; 1349 write_png(dp, dp->original_ip, 0/*transforms*/); 1350 read_png(dp, &dp->written_file, NULL, 0/*transforms*/); 1351 if (!compare_read(dp, 0/*transforms applied*/)) 1352 return; 1353 #endif 1354 1355 /* Third test: the active options. Test each in turn, or, with the 1356 * EXHAUSTIVE option, test all possible combinations. 1357 */ 1358 { 1359 /* Use unsigned int here because the code below to increment through all 1360 * the possibilities exhaustively has to use a compare and that must be 1361 * unsigned, because some transforms are negative on a 16-bit system. 1362 */ 1363 unsigned int active = dp->active_transforms; 1364 const int exhaustive = (dp->options & EXHAUSTIVE) != 0; 1365 unsigned int current = first_transform(active); 1366 unsigned int bad_transforms = 0; 1367 unsigned int bad_combo = ~0U; /* bitwise AND of failing transforms */ 1368 unsigned int bad_combo_list = 0; /* bitwise OR of failures */ 1369 1370 for (;;) 1371 { 1372 read_png(dp, &dp->original_file, "active transforms", current); 1373 1374 /* If this involved any irreversible transformations then if we write 1375 * it out with just the reversible transformations and read it in again 1376 * with the same transforms we should get the same thing. At present 1377 * this isn't done - it just seems like a waste of time and it would 1378 * require two sets of read png_struct/png_info. 1379 * 1380 * If there were no irreversible transformations then if we write it 1381 * out and read it back in again (without the reversible transforms) 1382 * we should get back to the place where we started. 1383 */ 1384 #ifdef PNG_WRITE_SUPPORTED 1385 if ((current & write_transforms) == current) 1386 { 1387 /* All transforms reversible: write the PNG with the transformations 1388 * reversed, then read it back in with no transformations. The 1389 * result should be the same as the original apart from the loss of 1390 * low order bits because of the SHIFT/sBIT transform. 1391 */ 1392 dp->operation = "reversible transforms"; 1393 write_png(dp, dp->read_ip, current); 1394 1395 /* And if this is read back in, because all the transformations were 1396 * reversible, the result should be the same. 1397 */ 1398 read_png(dp, &dp->written_file, NULL, 0); 1399 if (!compare_read(dp, current/*for the SHIFT/sBIT transform*/)) 1400 { 1401 /* This set of transforms failed. If a single bit is set - if 1402 * there is just one transform - don't include this in further 1403 * 'exhaustive' tests. Notice that each transform is tested on 1404 * its own before testing combos in the exhaustive case. 1405 */ 1406 if (is_combo(current)) 1407 { 1408 bad_combo &= current; 1409 bad_combo_list |= current; 1410 } 1411 1412 else 1413 bad_transforms |= current; 1414 } 1415 } 1416 #endif 1417 1418 /* Now move to the next transform */ 1419 if (exhaustive) /* all combinations */ 1420 { 1421 unsigned int next = current; 1422 1423 do 1424 { 1425 if (next == read_transforms) /* Everything tested */ 1426 goto combo; 1427 1428 ++next; 1429 } /* skip known bad combos if the relevant option is set; skip 1430 * combos involving known bad single transforms in all cases. 1431 */ 1432 while ( (next & read_transforms) <= current 1433 || (next & active) == 0 /* skip cases that do nothing */ 1434 || (next & bad_transforms) != 0 1435 || skip_transform(dp, next)); 1436 1437 assert((next & read_transforms) == next); 1438 current = next; 1439 } 1440 1441 else /* one at a time */ 1442 { 1443 active &= ~current; 1444 1445 if (active == 0) 1446 goto combo; 1447 1448 current = first_transform(active); 1449 } 1450 } 1451 1452 combo: 1453 if (dp->options & FIND_BAD_COMBOS) 1454 { 1455 /* bad_combos identifies the combos that occur in all failing cases; 1456 * bad_combo_list identifies transforms that do not prevent the 1457 * failure. 1458 */ 1459 if (bad_combo != ~0U) 1460 printf("%s[0x%x]: PROBLEM: 0x%x[0x%x] ANTIDOTE: 0x%x\n", 1461 dp->filename, active, bad_combo, bad_combo_list, 1462 rw_transforms & ~bad_combo_list); 1463 1464 else 1465 printf("%s: no %sbad combos found\n", dp->filename, 1466 (dp->options & SKIP_BUGS) ? "additional " : ""); 1467 } 1468 } 1469 } 1470 1471 static int 1472 do_test(struct display *dp, const char *file) 1473 /* Exists solely to isolate the setjmp clobbers */ 1474 { 1475 int ret = setjmp(dp->error_return); 1476 1477 if (ret == 0) 1478 { 1479 test_one_file(dp, file); 1480 return 0; 1481 } 1482 1483 else if (ret < ERRORS) /* shouldn't longjmp on warnings */ 1484 display_log(dp, INTERNAL_ERROR, "unexpected return code %d", ret); 1485 1486 return ret; 1487 } 1488 1489 int 1490 main(const int argc, const char * const * const argv) 1491 { 1492 /* For each file on the command line test it with a range of transforms */ 1493 int option_end, ilog = 0; 1494 struct display d; 1495 1496 validate_T(); 1497 display_init(&d); 1498 1499 for (option_end=1; option_end<argc; ++option_end) 1500 { 1501 const char *name = argv[option_end]; 1502 1503 if (strcmp(name, "--verbose") == 0) 1504 d.options = (d.options & ~LEVEL_MASK) | VERBOSE; 1505 1506 else if (strcmp(name, "--warnings") == 0) 1507 d.options = (d.options & ~LEVEL_MASK) | WARNINGS; 1508 1509 else if (strcmp(name, "--errors") == 0) 1510 d.options = (d.options & ~LEVEL_MASK) | ERRORS; 1511 1512 else if (strcmp(name, "--quiet") == 0) 1513 d.options = (d.options & ~LEVEL_MASK) | QUIET; 1514 1515 else if (strcmp(name, "--exhaustive") == 0) 1516 d.options |= EXHAUSTIVE; 1517 1518 else if (strcmp(name, "--fast") == 0) 1519 d.options &= ~EXHAUSTIVE; 1520 1521 else if (strcmp(name, "--strict") == 0) 1522 d.options |= STRICT; 1523 1524 else if (strcmp(name, "--relaxed") == 0) 1525 d.options &= ~STRICT; 1526 1527 else if (strcmp(name, "--log") == 0) 1528 { 1529 ilog = option_end; /* prevent display */ 1530 d.options |= LOG; 1531 } 1532 1533 else if (strcmp(name, "--nolog") == 0) 1534 d.options &= ~LOG; 1535 1536 else if (strcmp(name, "--continue") == 0) 1537 d.options |= CONTINUE; 1538 1539 else if (strcmp(name, "--stop") == 0) 1540 d.options &= ~CONTINUE; 1541 1542 else if (strcmp(name, "--skip-bugs") == 0) 1543 d.options |= SKIP_BUGS; 1544 1545 else if (strcmp(name, "--test-all") == 0) 1546 d.options &= ~SKIP_BUGS; 1547 1548 else if (strcmp(name, "--log-skipped") == 0) 1549 d.options |= LOG_SKIPPED; 1550 1551 else if (strcmp(name, "--nolog-skipped") == 0) 1552 d.options &= ~LOG_SKIPPED; 1553 1554 else if (strcmp(name, "--find-bad-combos") == 0) 1555 d.options |= FIND_BAD_COMBOS; 1556 1557 else if (strcmp(name, "--nofind-bad-combos") == 0) 1558 d.options &= ~FIND_BAD_COMBOS; 1559 1560 else if (name[0] == '-' && name[1] == '-') 1561 { 1562 fprintf(stderr, "pngimage: %s: unknown option\n", name); 1563 return 99; 1564 } 1565 1566 else 1567 break; /* Not an option */ 1568 } 1569 1570 { 1571 int i; 1572 int errors = 0; 1573 1574 for (i=option_end; i<argc; ++i) 1575 { 1576 { 1577 int ret = do_test(&d, argv[i]); 1578 1579 if (ret > QUIET) /* abort on user or internal error */ 1580 return 99; 1581 } 1582 1583 /* Here on any return, including failures, except user/internal issues 1584 */ 1585 { 1586 const int pass = (d.options & STRICT) ? 1587 RESULT_STRICT(d.results) : RESULT_RELAXED(d.results); 1588 1589 if (!pass) 1590 ++errors; 1591 1592 if (d.options & LOG) 1593 { 1594 int j; 1595 1596 printf("%s: pngimage ", pass ? "PASS" : "FAIL"); 1597 1598 for (j=1; j<option_end; ++j) if (j != ilog) 1599 printf("%s ", argv[j]); 1600 1601 printf("%s\n", d.filename); 1602 } 1603 } 1604 1605 display_clean(&d); 1606 } 1607 1608 return errors != 0; 1609 } 1610 } 1611 #else /* !PNG_INFO_IMAGE_SUPPORTED || !PNG_READ_SUPPORTED */ 1612 int 1613 main(void) 1614 { 1615 fprintf(stderr, "pngimage: no support for png_read/write_image\n"); 1616 return 77; 1617 } 1618 #endif 1619
