Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 1 | |
| 2 | /* tarith.c |
| 3 | * |
| 4 | * Copyright (c) 2011-2013 John Cunningham Bowler |
| 5 | * |
| 6 | * Last changed in libpng 1.6.0 [February 14, 2013] |
| 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 | * Test internal arithmetic functions of libpng. |
| 13 | * |
| 14 | * This code must be linked against a math library (-lm), but does not require |
| 15 | * libpng or zlib to work. Because it includes the complete source of 'png.c' |
| 16 | * it tests the code with whatever compiler options are used to build it. |
| 17 | * Changing these options can substantially change the errors in the |
| 18 | * calculations that the compiler chooses! |
| 19 | */ |
| 20 | #define _POSIX_SOURCE 1 |
| 21 | #define _ISOC99_SOURCE 1 |
| 22 | |
| 23 | /* Obtain a copy of the code to be tested (plus other things), disabling |
| 24 | * stuff that is not required. |
| 25 | */ |
| 26 | #include <math.h> |
| 27 | #include <stdlib.h> |
| 28 | #include <ctype.h> |
| 29 | #include <string.h> |
| 30 | #include <assert.h> |
| 31 | |
| 32 | #include "../../pngpriv.h" |
| 33 | |
| 34 | #define png_error png_warning |
| 35 | |
| 36 | void png_warning(png_const_structrp png_ptr, png_const_charp msg) |
| 37 | { |
| 38 | fprintf(stderr, "validation: %s\n", msg); |
| 39 | } |
| 40 | |
| 41 | #define png_fixed_error png_fixed_warning |
| 42 | |
| 43 | void png_fixed_warning(png_const_structrp png_ptr, png_const_charp msg) |
| 44 | { |
| 45 | fprintf(stderr, "overflow in: %s\n", msg); |
| 46 | } |
| 47 | |
| 48 | #define png_set_error_fn(pp, ep, efp, wfp) ((void)0) |
| 49 | #define png_malloc(pp, s) malloc(s) |
| 50 | #define png_malloc_warn(pp, s) malloc(s) |
| 51 | #define png_malloc_base(pp, s) malloc(s) |
| 52 | #define png_calloc(pp, s) calloc(1, (s)) |
| 53 | #define png_free(pp, s) free(s) |
| 54 | |
| 55 | #define png_safecat(b, sb, pos, str) (pos) |
| 56 | #define png_format_number(start, end, format, number) (start) |
| 57 | |
| 58 | #define crc32(crc, pp, s) (crc) |
| 59 | #define inflateReset(zs) Z_OK |
| 60 | |
| 61 | #define png_create_struct(type) (0) |
| 62 | #define png_destroy_struct(pp) ((void)0) |
| 63 | #define png_create_struct_2(type, m, mm) (0) |
| 64 | #define png_destroy_struct_2(pp, f, mm) ((void)0) |
| 65 | |
| 66 | #undef PNG_SIMPLIFIED_READ_SUPPORTED |
| 67 | #undef PNG_SIMPLIFIED_WRITE_SUPPORTED |
| 68 | #undef PNG_USER_MEM_SUPPORTED |
| 69 | |
| 70 | #include "../../png.c" |
| 71 | |
| 72 | /* Validate ASCII to fp routines. */ |
| 73 | static int verbose = 0; |
| 74 | |
| 75 | int validation_ascii_to_fp(int count, int argc, char **argv) |
| 76 | { |
| 77 | int showall = 0; |
| 78 | double max_error=2; /* As a percentage error-in-last-digit/.5 */ |
| 79 | double max_error_abs=17; /* Used when precision is DBL_DIG */ |
| 80 | double max = 0; |
| 81 | double max_abs = 0; |
| 82 | double test = 0; /* Important to test this. */ |
| 83 | int precision = 5; |
| 84 | int nonfinite = 0; |
| 85 | int finite = 0; |
| 86 | int ok = 0; |
| 87 | int failcount = 0; |
| 88 | int minorarith = 0; |
| 89 | |
| 90 | while (--argc > 0) |
| 91 | if (strcmp(*++argv, "-a") == 0) |
| 92 | showall = 1; |
| 93 | else if (strcmp(*argv, "-e") == 0 && argc > 0) |
| 94 | { |
| 95 | --argc; |
| 96 | max_error = atof(*++argv); |
| 97 | } |
| 98 | else if (strcmp(*argv, "-E") == 0 && argc > 0) |
| 99 | { |
| 100 | --argc; |
| 101 | max_error_abs = atof(*++argv); |
| 102 | } |
| 103 | else |
| 104 | { |
| 105 | fprintf(stderr, "unknown argument %s\n", *argv); |
| 106 | return 1; |
| 107 | } |
| 108 | |
| 109 | do |
| 110 | { |
| 111 | png_size_t index; |
| 112 | int state, failed = 0; |
| 113 | char buffer[64]; |
| 114 | |
| 115 | if (isfinite(test)) |
| 116 | ++finite; |
| 117 | else |
| 118 | ++nonfinite; |
| 119 | |
| 120 | if (verbose) |
| 121 | fprintf(stderr, "%.*g %d\n", DBL_DIG, test, precision); |
| 122 | |
| 123 | /* Check for overflow in the buffer by setting a marker. */ |
| 124 | memset(buffer, 71, sizeof buffer); |
| 125 | |
| 126 | png_ascii_from_fp(0, buffer, precision+10, test, precision); |
| 127 | |
| 128 | /* Allow for a three digit exponent, this stuff will fail if |
| 129 | * the exponent is bigger than this! |
| 130 | */ |
| 131 | if (buffer[precision+7] != 71) |
| 132 | { |
| 133 | fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test, |
| 134 | precision, buffer, (unsigned long)strlen(buffer)); |
| 135 | failed = 1; |
| 136 | } |
| 137 | |
| 138 | /* Following are used for the number parser below and must be |
| 139 | * initialized to zero. |
| 140 | */ |
| 141 | state = 0; |
| 142 | index = 0; |
| 143 | if (!isfinite(test)) |
| 144 | { |
| 145 | /* Expect 'inf' */ |
| 146 | if (test >= 0 && strcmp(buffer, "inf") || |
| 147 | test < 0 && strcmp(buffer, "-inf")) |
| 148 | { |
| 149 | fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test, |
| 150 | precision, buffer); |
| 151 | failed = 1; |
| 152 | } |
| 153 | } |
| 154 | else if (!png_check_fp_number(buffer, precision+10, &state, &index) || |
| 155 | buffer[index] != 0) |
| 156 | { |
| 157 | fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test, |
| 158 | precision, buffer, buffer[index]); |
| 159 | failed = 1; |
| 160 | } |
| 161 | else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0)) |
| 162 | { |
| 163 | fprintf(stderr, "%g[%d] -> '%s' but negative value not so reported\n", |
| 164 | test, precision, buffer); |
| 165 | failed = 1; |
| 166 | assert(!PNG_FP_IS_ZERO(state)); |
| 167 | assert(!PNG_FP_IS_POSITIVE(state)); |
| 168 | } |
| 169 | else if (PNG_FP_IS_ZERO(state) && !(test == 0)) |
| 170 | { |
| 171 | fprintf(stderr, "%g[%d] -> '%s' but zero value not so reported\n", |
| 172 | test, precision, buffer); |
| 173 | failed = 1; |
| 174 | assert(!PNG_FP_IS_NEGATIVE(state)); |
| 175 | assert(!PNG_FP_IS_POSITIVE(state)); |
| 176 | } |
| 177 | else if (PNG_FP_IS_POSITIVE(state) && !(test > 0)) |
| 178 | { |
| 179 | fprintf(stderr, "%g[%d] -> '%s' but postive value not so reported\n", |
| 180 | test, precision, buffer); |
| 181 | failed = 1; |
| 182 | assert(!PNG_FP_IS_NEGATIVE(state)); |
| 183 | assert(!PNG_FP_IS_ZERO(state)); |
| 184 | } |
| 185 | else |
| 186 | { |
| 187 | /* Check the result against the original. */ |
| 188 | double out = atof(buffer); |
| 189 | double change = fabs((out - test)/test); |
| 190 | double allow = .5/pow(10, |
| 191 | (precision >= DBL_DIG) ? DBL_DIG-1 : precision-1); |
| 192 | |
| 193 | /* NOTE: if you hit this error case are you compiling with gcc |
| 194 | * and -O0? Try -O2 - the errors can accumulate if the FP |
| 195 | * code above is not optimized and may drift outside the .5 in |
| 196 | * DBL_DIG allowed. In any case a small number of errors may |
| 197 | * occur (very small ones - 1 or 2%) because of rounding in the |
| 198 | * calculations, either in the conversion API or in atof. |
| 199 | */ |
| 200 | if (change >= allow && (isfinite(out) || |
| 201 | fabs(test/DBL_MAX) <= 1-allow)) |
| 202 | { |
| 203 | double percent = (precision >= DBL_DIG) ? max_error_abs : max_error; |
| 204 | double allowp = (change-allow)*100/allow; |
| 205 | |
| 206 | if (precision >= DBL_DIG) |
| 207 | { |
| 208 | if (max_abs < allowp) max_abs = allowp; |
| 209 | } |
| 210 | |
| 211 | else |
| 212 | { |
| 213 | if (max < allowp) max = allowp; |
| 214 | } |
| 215 | |
| 216 | if (showall || allowp >= percent) |
| 217 | { |
| 218 | fprintf(stderr, |
| 219 | "%.*g[%d] -> '%s' -> %.*g number changed (%g > %g (%d%%))\n", |
| 220 | DBL_DIG, test, precision, buffer, DBL_DIG, out, change, allow, |
| 221 | (int)round(allowp)); |
| 222 | failed = 1; |
| 223 | } |
| 224 | else |
| 225 | ++minorarith; |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | if (failed) |
| 230 | ++failcount; |
| 231 | else |
| 232 | ++ok; |
| 233 | |
| 234 | skip: |
| 235 | /* Generate a new number and precision. */ |
| 236 | precision = rand(); |
| 237 | if (precision & 1) test = -test; |
| 238 | precision >>= 1; |
| 239 | |
| 240 | /* Generate random numbers. */ |
| 241 | if (test == 0 || !isfinite(test)) |
| 242 | test = precision+1; |
| 243 | else |
| 244 | { |
| 245 | /* Derive the exponent from the previous rand() value. */ |
| 246 | int exponent = precision % (DBL_MAX_EXP - DBL_MIN_EXP) + DBL_MIN_EXP; |
| 247 | int tmp; |
| 248 | test = frexp(test * rand(), &tmp); |
| 249 | test = ldexp(test, exponent); |
| 250 | precision >>= 8; /* arbitrary */ |
| 251 | } |
| 252 | |
| 253 | /* This limits the precision to 32 digits, enough for standard |
| 254 | * IEEE implementations which have at most 15 digits. |
| 255 | */ |
| 256 | precision = (precision & 0x1f) + 1; |
| 257 | } |
| 258 | while (--count); |
| 259 | |
| 260 | printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor " |
| 261 | "arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith); |
| 262 | printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs); |
| 263 | printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max); |
| 264 | |
| 265 | return 0; |
| 266 | } |
| 267 | |
| 268 | /* Observe that valid FP numbers have the forms listed in the PNG extensions |
| 269 | * specification: |
| 270 | * |
| 271 | * [+,-]{integer,integer.fraction,.fraction}[{e,E}[+,-]integer] |
| 272 | * |
| 273 | * Test each of these in turn, including invalid cases. |
| 274 | */ |
| 275 | typedef enum checkfp_state |
| 276 | { |
| 277 | start, fraction, exponent, states |
| 278 | } checkfp_state; |
| 279 | |
| 280 | /* The characters (other than digits) that characterize the states: */ |
| 281 | static const char none[] = ""; |
| 282 | static const char hexdigits[16] = "0123456789ABCDEF"; |
| 283 | |
| 284 | static const struct |
| 285 | { |
| 286 | const char *start; /* Characters valid at the start */ |
| 287 | const char *end; /* Valid characters that end the state */ |
| 288 | const char *tests; /* Characters to test after 2 digits seen */ |
| 289 | } |
| 290 | state_characters[states] = |
| 291 | { |
| 292 | /* start: */ { "+-.", ".eE", "+-.e*0369" }, |
| 293 | /* fraction: */ { none, "eE", "+-.E#0147" }, |
| 294 | /* exponent: */ { "+-", none, "+-.eE^0258" } |
| 295 | }; |
| 296 | |
| 297 | typedef struct |
| 298 | { |
| 299 | char number[1024]; /* Buffer for number being tested */ |
| 300 | int limit; /* Command line limit */ |
| 301 | int verbose; /* Shadows global variable */ |
| 302 | int ctimes; /* Number of numbers tested */ |
| 303 | int cmillions; /* Count of millions of numbers */ |
| 304 | int cinvalid; /* Invalid strings checked */ |
| 305 | int cnoaccept; /* Characters not accepted */ |
| 306 | } |
| 307 | checkfp_command; |
| 308 | |
| 309 | typedef struct |
| 310 | { |
| 311 | int cnumber; /* Index into number string */ |
| 312 | checkfp_state check_state; /* Current number state */ |
| 313 | int at_start; /* At start (first character) of state */ |
| 314 | int cdigits_in_state; /* Digits seen in that state */ |
| 315 | int limit; /* Limit on same for checking all chars */ |
| 316 | int state; /* Current parser state */ |
| 317 | int is_negative; /* Number is negative */ |
| 318 | int is_zero; /* Number is (still) zero */ |
| 319 | int number_was_valid; /* Previous character validity */ |
| 320 | } |
| 321 | checkfp_control; |
| 322 | |
| 323 | static int check_all_characters(checkfp_command *co, checkfp_control c); |
| 324 | |
| 325 | static int check_some_characters(checkfp_command *co, checkfp_control c, |
| 326 | const char *tests); |
| 327 | |
| 328 | static int check_one_character(checkfp_command *co, checkfp_control c, int ch) |
| 329 | { |
| 330 | /* Test this character (ch) to ensure the parser does the correct thing. |
| 331 | */ |
| 332 | png_size_t index = 0; |
| 333 | const char test = (char)ch; |
| 334 | const int number_is_valid = png_check_fp_number(&test, 1, &c.state, &index); |
| 335 | const int character_accepted = (index == 1); |
| 336 | |
| 337 | if (c.check_state != exponent && isdigit(ch) && ch != '0') |
| 338 | c.is_zero = 0; |
| 339 | |
| 340 | if (c.check_state == start && c.at_start && ch == '-') |
| 341 | c.is_negative = 1; |
| 342 | |
| 343 | if (isprint(ch)) |
| 344 | co->number[c.cnumber++] = (char)ch; |
| 345 | else |
| 346 | { |
| 347 | co->number[c.cnumber++] = '<'; |
| 348 | co->number[c.cnumber++] = hexdigits[(ch >> 4) & 0xf]; |
| 349 | co->number[c.cnumber++] = hexdigits[ch & 0xf]; |
| 350 | co->number[c.cnumber++] = '>'; |
| 351 | } |
| 352 | co->number[c.cnumber] = 0; |
| 353 | |
| 354 | if (co->verbose > 1) |
| 355 | fprintf(stderr, "%s\n", co->number); |
| 356 | |
| 357 | if (++(co->ctimes) == 1000000) |
| 358 | { |
| 359 | if (co->verbose == 1) |
| 360 | fputc('.', stderr); |
| 361 | co->ctimes = 0; |
| 362 | ++(co->cmillions); |
| 363 | } |
| 364 | |
| 365 | if (!number_is_valid) |
| 366 | ++(co->cinvalid); |
| 367 | |
| 368 | if (!character_accepted) |
| 369 | ++(co->cnoaccept); |
| 370 | |
| 371 | /* This should never fail (it's a serious bug if it does): */ |
| 372 | if (index != 0 && index != 1) |
| 373 | { |
| 374 | fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number, |
| 375 | (unsigned long)index); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | /* Validate the new state, note that the PNG_FP_IS_ macros all return |
| 380 | * false unless the number is valid. |
| 381 | */ |
| 382 | if (PNG_FP_IS_NEGATIVE(c.state) != |
| 383 | (number_is_valid && !c.is_zero && c.is_negative)) |
| 384 | { |
| 385 | fprintf(stderr, "%s: negative when it is not\n", co->number); |
| 386 | return 0; |
| 387 | } |
| 388 | |
| 389 | if (PNG_FP_IS_ZERO(c.state) != (number_is_valid && c.is_zero)) |
| 390 | { |
| 391 | fprintf(stderr, "%s: zero when it is not\n", co->number); |
| 392 | return 0; |
| 393 | } |
| 394 | |
| 395 | if (PNG_FP_IS_POSITIVE(c.state) != |
| 396 | (number_is_valid && !c.is_zero && !c.is_negative)) |
| 397 | { |
| 398 | fprintf(stderr, "%s: positive when it is not\n", co->number); |
| 399 | return 0; |
| 400 | } |
| 401 | |
| 402 | /* Testing a digit */ |
| 403 | if (isdigit(ch)) |
| 404 | { |
| 405 | if (!character_accepted) |
| 406 | { |
| 407 | fprintf(stderr, "%s: digit '%c' not accepted\n", co->number, ch); |
| 408 | return 0; |
| 409 | } |
| 410 | |
| 411 | if (!number_is_valid) |
| 412 | { |
| 413 | fprintf(stderr, "%s: saw a digit (%c) but number not valid\n", |
| 414 | co->number, ch); |
| 415 | return 0; |
| 416 | } |
| 417 | |
| 418 | ++c.cdigits_in_state; |
| 419 | c.at_start = 0; |
| 420 | c.number_was_valid = 1; |
| 421 | |
| 422 | /* Continue testing characters in this state. Either test all of |
| 423 | * them or, if we have already seen one digit in this state, just test a |
| 424 | * limited set. |
| 425 | */ |
| 426 | if (c.cdigits_in_state < 1) |
| 427 | return check_all_characters(co, c); |
| 428 | |
| 429 | else |
| 430 | return check_some_characters(co, c, |
| 431 | state_characters[c.check_state].tests); |
| 432 | } |
| 433 | |
| 434 | /* A non-digit; is it allowed here? */ |
| 435 | else if (((ch == '+' || ch == '-') && c.check_state != fraction && |
| 436 | c.at_start) || |
| 437 | (ch == '.' && c.check_state == start) || |
| 438 | ((ch == 'e' || ch == 'E') && c.number_was_valid && |
| 439 | c.check_state != exponent)) |
| 440 | { |
| 441 | if (!character_accepted) |
| 442 | { |
| 443 | fprintf(stderr, "%s: character '%c' not accepted\n", co->number, ch); |
| 444 | return 0; |
| 445 | } |
| 446 | |
| 447 | /* The number remains valid after start of fraction but nowhere else. */ |
| 448 | if (number_is_valid && (c.check_state != start || ch != '.')) |
| 449 | { |
| 450 | fprintf(stderr, "%s: saw a non-digit (%c) but number valid\n", |
| 451 | co->number, ch); |
| 452 | return 0; |
| 453 | } |
| 454 | |
| 455 | c.number_was_valid = number_is_valid; |
| 456 | |
| 457 | /* Check for a state change. When changing to 'fraction' if the number |
| 458 | * is valid at this point set the at_start to false to allow an exponent |
| 459 | * 'e' to come next. |
| 460 | */ |
| 461 | if (c.check_state == start && ch == '.') |
| 462 | { |
| 463 | c.check_state = fraction; |
| 464 | c.at_start = !number_is_valid; |
| 465 | c.cdigits_in_state = 0; |
| 466 | c.limit = co->limit; |
| 467 | return check_all_characters(co, c); |
| 468 | } |
| 469 | |
| 470 | else if (c.check_state < exponent && (ch == 'e' || ch == 'E')) |
| 471 | { |
| 472 | c.check_state = exponent; |
| 473 | c.at_start = 1; |
| 474 | c.cdigits_in_state = 0; |
| 475 | c.limit = co->limit; |
| 476 | return check_all_characters(co, c); |
| 477 | } |
| 478 | |
| 479 | /* Else it was a sign, and the state doesn't change. */ |
| 480 | else |
| 481 | { |
| 482 | if (ch != '-' && ch != '+') |
| 483 | { |
| 484 | fprintf(stderr, "checkfp: internal error (1)\n"); |
| 485 | return 0; |
| 486 | } |
| 487 | |
| 488 | c.at_start = 0; |
| 489 | return check_all_characters(co, c); |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | /* Testing an invalid character */ |
| 494 | else |
| 495 | { |
| 496 | if (character_accepted) |
| 497 | { |
| 498 | fprintf(stderr, "%s: character '%c' [0x%.2x] accepted\n", co->number, |
| 499 | ch, ch); |
| 500 | return 0; |
| 501 | } |
| 502 | |
| 503 | if (number_is_valid != c.number_was_valid) |
| 504 | { |
| 505 | fprintf(stderr, |
| 506 | "%s: character '%c' [0x%.2x] changed number validity\n", co->number, |
| 507 | ch, ch); |
| 508 | return 0; |
| 509 | } |
| 510 | |
| 511 | /* Do nothing - the parser has stuck; return success and keep going with |
| 512 | * the next character. |
| 513 | */ |
| 514 | } |
| 515 | |
| 516 | /* Successful return (the caller will try the next character.) */ |
| 517 | return 1; |
| 518 | } |
| 519 | |
| 520 | static int check_all_characters(checkfp_command *co, checkfp_control c) |
| 521 | { |
| 522 | int ch; |
| 523 | |
| 524 | if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch) |
| 525 | { |
| 526 | if (!check_one_character(co, c, ch)) |
| 527 | return 0; |
| 528 | } |
| 529 | |
| 530 | return 1; |
| 531 | } |
| 532 | |
| 533 | static int check_some_characters(checkfp_command *co, checkfp_control c, |
| 534 | const char *tests) |
| 535 | { |
| 536 | int i; |
| 537 | |
| 538 | --(c.limit); |
| 539 | |
| 540 | if (c.cnumber+4 < sizeof co->number && c.limit >= 0) |
| 541 | { |
| 542 | if (c.limit > 0) for (i=0; tests[i]; ++i) |
| 543 | { |
| 544 | if (!check_one_character(co, c, tests[i])) |
| 545 | return 0; |
| 546 | } |
| 547 | |
| 548 | /* At the end check all the characters. */ |
| 549 | else |
| 550 | return check_all_characters(co, c); |
| 551 | } |
| 552 | |
| 553 | return 1; |
| 554 | } |
| 555 | |
| 556 | int validation_checkfp(int count, int argc, char **argv) |
| 557 | { |
| 558 | int result; |
| 559 | checkfp_command command; |
| 560 | checkfp_control control; |
| 561 | |
| 562 | command.number[0] = 0; |
| 563 | command.limit = 3; |
| 564 | command.verbose = verbose; |
| 565 | command.ctimes = 0; |
| 566 | command.cmillions = 0; |
| 567 | command.cinvalid = 0; |
| 568 | command.cnoaccept = 0; |
| 569 | |
| 570 | while (--argc > 0) |
| 571 | { |
| 572 | ++argv; |
| 573 | if (argc > 1 && strcmp(*argv, "-l") == 0) |
| 574 | { |
| 575 | --argc; |
| 576 | command.limit = atoi(*++argv); |
| 577 | } |
| 578 | |
| 579 | else |
| 580 | { |
| 581 | fprintf(stderr, "unknown argument %s\n", *argv); |
| 582 | return 1; |
| 583 | } |
| 584 | } |
| 585 | |
| 586 | control.cnumber = 0; |
| 587 | control.check_state = start; |
| 588 | control.at_start = 1; |
| 589 | control.cdigits_in_state = 0; |
| 590 | control.limit = command.limit; |
| 591 | control.state = 0; |
| 592 | control.is_negative = 0; |
| 593 | control.is_zero = 1; |
| 594 | control.number_was_valid = 0; |
| 595 | |
| 596 | result = check_all_characters(&command, control); |
| 597 | |
| 598 | printf("checkfp: %s: checked %d,%.3d,%.3d,%.3d strings (%d invalid)\n", |
| 599 | result ? "pass" : "FAIL", command.cmillions / 1000, |
| 600 | command.cmillions % 1000, command.ctimes / 1000, command.ctimes % 1000, |
| 601 | command.cinvalid); |
| 602 | |
| 603 | return result; |
| 604 | } |
| 605 | |
| 606 | int validation_muldiv(int count, int argc, char **argv) |
| 607 | { |
| 608 | int tested = 0; |
| 609 | int overflow = 0; |
| 610 | int error = 0; |
| 611 | int error64 = 0; |
| 612 | int passed = 0; |
| 613 | int randbits = 0; |
| 614 | png_uint_32 randbuffer; |
| 615 | png_fixed_point a; |
| 616 | png_int_32 times, div; |
| 617 | |
| 618 | while (--argc > 0) |
| 619 | { |
| 620 | fprintf(stderr, "unknown argument %s\n", *++argv); |
| 621 | return 1; |
| 622 | } |
| 623 | |
| 624 | /* Find out about the random number generator. */ |
| 625 | randbuffer = RAND_MAX; |
| 626 | while (randbuffer != 0) ++randbits, randbuffer >>= 1; |
| 627 | printf("Using random number generator that makes %d bits\n", randbits); |
| 628 | for (div=0; div<32; div += randbits) |
| 629 | randbuffer = (randbuffer << randbits) ^ rand(); |
| 630 | |
| 631 | a = 0; |
| 632 | times = div = 0; |
| 633 | do |
| 634 | { |
| 635 | png_fixed_point result; |
| 636 | /* NOTE: your mileage may vary, a type is required below that can |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 637 | * hold 64 bits or more, if floating point is used a 64-bit or |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 638 | * better mantissa is required. |
| 639 | */ |
| 640 | long long int fp, fpround; |
| 641 | unsigned long hi, lo; |
| 642 | int ok; |
| 643 | |
| 644 | /* Check the values, png_64bit_product can only handle positive |
| 645 | * numbers, so correct for that here. |
| 646 | */ |
| 647 | { |
| 648 | long u1, u2; |
| 649 | int n = 0; |
| 650 | if (a < 0) u1 = -a, n = 1; else u1 = a; |
| 651 | if (times < 0) u2 = -times, n = !n; else u2 = times; |
| 652 | png_64bit_product(u1, u2, &hi, &lo); |
| 653 | if (n) |
| 654 | { |
| 655 | /* -x = ~x+1 */ |
| 656 | lo = ((~lo) + 1) & 0xffffffff; |
| 657 | hi = ~hi; |
| 658 | if (lo == 0) ++hi; |
| 659 | } |
| 660 | } |
| 661 | |
| 662 | fp = a; |
| 663 | fp *= times; |
| 664 | if ((fp & 0xffffffff) != lo || ((fp >> 32) & 0xffffffff) != hi) |
| 665 | { |
| 666 | fprintf(stderr, "png_64bit_product %d * %d -> %lx|%.8lx not %llx\n", |
| 667 | a, times, hi, lo, fp); |
| 668 | ++error64; |
| 669 | } |
| 670 | |
| 671 | if (div != 0) |
| 672 | { |
| 673 | /* Round - this is C round to zero. */ |
| 674 | if ((fp < 0) != (div < 0)) |
| 675 | fp -= div/2; |
| 676 | else |
| 677 | fp += div/2; |
| 678 | |
| 679 | fp /= div; |
| 680 | fpround = fp; |
| 681 | /* Assume 2's complement here: */ |
| 682 | ok = fpround <= PNG_UINT_31_MAX && |
| 683 | fpround >= -1-(long long int)PNG_UINT_31_MAX; |
| 684 | if (!ok) ++overflow; |
| 685 | } |
| 686 | else |
| 687 | ok = 0, ++overflow, fpround = fp/*misleading*/; |
| 688 | |
| 689 | if (verbose) |
| 690 | fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div, |
| 691 | fp, ok ? "ok" : "overflow"); |
| 692 | |
| 693 | ++tested; |
| 694 | if (png_muldiv(&result, a, times, div) != ok) |
| 695 | { |
| 696 | ++error; |
| 697 | if (ok) |
| 698 | fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a, |
| 699 | times, div, fp); |
| 700 | else |
| 701 | fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a, |
| 702 | times, div, result, fp); |
| 703 | } |
| 704 | else if (ok && result != fpround) |
| 705 | { |
| 706 | ++error; |
| 707 | fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result, |
| 708 | fp); |
| 709 | } |
| 710 | else |
| 711 | ++passed; |
| 712 | |
| 713 | /* Generate three new values, this uses rand() and rand() only returns |
| 714 | * up to RAND_MAX. |
| 715 | */ |
| 716 | /* CRUDE */ |
| 717 | a += times; |
| 718 | times += div; |
| 719 | div = randbuffer; |
| 720 | randbuffer = (randbuffer << randbits) ^ rand(); |
| 721 | } |
| 722 | while (--count > 0); |
| 723 | |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 724 | printf("%d tests including %d overflows, %d passed, %d failed (%d 64-bit " |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 725 | "errors)\n", tested, overflow, passed, error, error64); |
| 726 | return 0; |
| 727 | } |
| 728 | |
| 729 | /* When FP is on this just becomes a speed test - compile without FP to get real |
| 730 | * validation. |
| 731 | */ |
| 732 | #ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED |
| 733 | #define LN2 .000010576586617430806112933839 /* log(2)/65536 */ |
| 734 | #define L2INV 94548.46219969910586572651 /* 65536/log(2) */ |
| 735 | |
| 736 | /* For speed testing, need the internal functions too: */ |
| 737 | static png_uint_32 png_log8bit(unsigned x) |
| 738 | { |
| 739 | if (x > 0) |
| 740 | return (png_uint_32)floor(.5-log(x/255.)*L2INV); |
| 741 | |
| 742 | return 0xffffffff; |
| 743 | } |
| 744 | |
| 745 | static png_uint_32 png_log16bit(png_uint_32 x) |
| 746 | { |
| 747 | if (x > 0) |
| 748 | return (png_uint_32)floor(.5-log(x/65535.)*L2INV); |
| 749 | |
| 750 | return 0xffffffff; |
| 751 | } |
| 752 | |
| 753 | static png_uint_32 png_exp(png_uint_32 x) |
| 754 | { |
| 755 | return (png_uint_32)floor(.5 + exp(x * -LN2) * 0xffffffffU); |
| 756 | } |
| 757 | |
| 758 | static png_byte png_exp8bit(png_uint_32 log) |
| 759 | { |
| 760 | return (png_byte)floor(.5 + exp(log * -LN2) * 255); |
| 761 | } |
| 762 | |
| 763 | static png_uint_16 png_exp16bit(png_uint_32 log) |
| 764 | { |
| 765 | return (png_uint_16)floor(.5 + exp(log * -LN2) * 65535); |
| 766 | } |
| 767 | #endif /* FLOATING_ARITHMETIC */ |
| 768 | |
| 769 | int validation_gamma(int argc, char **argv) |
| 770 | { |
| 771 | double gamma[9] = { 2.2, 1.8, 1.52, 1.45, 1., 1/1.45, 1/1.52, 1/1.8, 1/2.2 }; |
| 772 | double maxerr; |
| 773 | int i, silent=0, onlygamma=0; |
| 774 | |
| 775 | /* Silence the output with -s, just test the gamma functions with -g: */ |
| 776 | while (--argc > 0) |
| 777 | if (strcmp(*++argv, "-s") == 0) |
| 778 | silent = 1; |
| 779 | else if (strcmp(*argv, "-g") == 0) |
| 780 | onlygamma = 1; |
| 781 | else |
| 782 | { |
| 783 | fprintf(stderr, "unknown argument %s\n", *argv); |
| 784 | return 1; |
| 785 | } |
| 786 | |
| 787 | if (!onlygamma) |
| 788 | { |
| 789 | /* First validate the log functions: */ |
| 790 | maxerr = 0; |
| 791 | for (i=0; i<256; ++i) |
| 792 | { |
| 793 | double correct = -log(i/255.)/log(2.)*65536; |
| 794 | double error = png_log8bit(i) - correct; |
| 795 | |
| 796 | if (i != 0 && fabs(error) > maxerr) |
| 797 | maxerr = fabs(error); |
| 798 | |
| 799 | if (i == 0 && png_log8bit(i) != 0xffffffff || |
| 800 | i != 0 && png_log8bit(i) != floor(correct+.5)) |
| 801 | { |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 802 | fprintf(stderr, "8-bit log error: %d: got %u, expected %f\n", |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 803 | i, png_log8bit(i), correct); |
| 804 | } |
| 805 | } |
| 806 | |
| 807 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 808 | printf("maximum 8-bit log error = %f\n", maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 809 | |
| 810 | maxerr = 0; |
| 811 | for (i=0; i<65536; ++i) |
| 812 | { |
| 813 | double correct = -log(i/65535.)/log(2.)*65536; |
| 814 | double error = png_log16bit(i) - correct; |
| 815 | |
| 816 | if (i != 0 && fabs(error) > maxerr) |
| 817 | maxerr = fabs(error); |
| 818 | |
| 819 | if (i == 0 && png_log16bit(i) != 0xffffffff || |
| 820 | i != 0 && png_log16bit(i) != floor(correct+.5)) |
| 821 | { |
| 822 | if (error > .68) /* By experiment error is less than .68 */ |
| 823 | { |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 824 | fprintf(stderr, "16-bit log error: %d: got %u, expected %f" |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 825 | " error: %f\n", i, png_log16bit(i), correct, error); |
| 826 | } |
| 827 | } |
| 828 | } |
| 829 | |
| 830 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 831 | printf("maximum 16-bit log error = %f\n", maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 832 | |
| 833 | /* Now exponentiations. */ |
| 834 | maxerr = 0; |
| 835 | for (i=0; i<=0xfffff; ++i) |
| 836 | { |
| 837 | double correct = exp(-i/65536. * log(2.)) * (65536. * 65536); |
| 838 | double error = png_exp(i) - correct; |
| 839 | |
| 840 | if (fabs(error) > maxerr) |
| 841 | maxerr = fabs(error); |
| 842 | if (fabs(error) > 1883) /* By experiment. */ |
| 843 | { |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 844 | fprintf(stderr, "32-bit exp error: %d: got %u, expected %f" |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 845 | " error: %f\n", i, png_exp(i), correct, error); |
| 846 | } |
| 847 | } |
| 848 | |
| 849 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 850 | printf("maximum 32-bit exp error = %f\n", maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 851 | |
| 852 | maxerr = 0; |
| 853 | for (i=0; i<=0xfffff; ++i) |
| 854 | { |
| 855 | double correct = exp(-i/65536. * log(2.)) * 255; |
| 856 | double error = png_exp8bit(i) - correct; |
| 857 | |
| 858 | if (fabs(error) > maxerr) |
| 859 | maxerr = fabs(error); |
| 860 | if (fabs(error) > .50002) /* By experiment */ |
| 861 | { |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 862 | fprintf(stderr, "8-bit exp error: %d: got %u, expected %f" |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 863 | " error: %f\n", i, png_exp8bit(i), correct, error); |
| 864 | } |
| 865 | } |
| 866 | |
| 867 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 868 | printf("maximum 8-bit exp error = %f\n", maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 869 | |
| 870 | maxerr = 0; |
| 871 | for (i=0; i<=0xfffff; ++i) |
| 872 | { |
| 873 | double correct = exp(-i/65536. * log(2.)) * 65535; |
| 874 | double error = png_exp16bit(i) - correct; |
| 875 | |
| 876 | if (fabs(error) > maxerr) |
| 877 | maxerr = fabs(error); |
| 878 | if (fabs(error) > .524) /* By experiment */ |
| 879 | { |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 880 | fprintf(stderr, "16-bit exp error: %d: got %u, expected %f" |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 881 | " error: %f\n", i, png_exp16bit(i), correct, error); |
| 882 | } |
| 883 | } |
| 884 | |
| 885 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 886 | printf("maximum 16-bit exp error = %f\n", maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 887 | } /* !onlygamma */ |
| 888 | |
| 889 | /* Test the overall gamma correction. */ |
| 890 | for (i=0; i<9; ++i) |
| 891 | { |
| 892 | unsigned j; |
| 893 | double g = gamma[i]; |
| 894 | png_fixed_point gfp = floor(g * PNG_FP_1 + .5); |
| 895 | |
| 896 | if (!silent) |
| 897 | printf("Test gamma %f\n", g); |
| 898 | |
| 899 | maxerr = 0; |
| 900 | for (j=0; j<256; ++j) |
| 901 | { |
| 902 | double correct = pow(j/255., g) * 255; |
| 903 | png_byte out = png_gamma_8bit_correct(j, gfp); |
| 904 | double error = out - correct; |
| 905 | |
| 906 | if (fabs(error) > maxerr) |
| 907 | maxerr = fabs(error); |
| 908 | if (out != floor(correct+.5)) |
| 909 | { |
| 910 | fprintf(stderr, "8bit %d ^ %f: got %d expected %f error %f\n", |
| 911 | j, g, out, correct, error); |
| 912 | } |
| 913 | } |
| 914 | |
| 915 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 916 | printf("gamma %f: maximum 8-bit error %f\n", g, maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 917 | |
| 918 | maxerr = 0; |
| 919 | for (j=0; j<65536; ++j) |
| 920 | { |
| 921 | double correct = pow(j/65535., g) * 65535; |
| 922 | png_uint_16 out = png_gamma_16bit_correct(j, gfp); |
| 923 | double error = out - correct; |
| 924 | |
| 925 | if (fabs(error) > maxerr) |
| 926 | maxerr = fabs(error); |
| 927 | if (fabs(error) > 1.62) |
| 928 | { |
| 929 | fprintf(stderr, "16bit %d ^ %f: got %d expected %f error %f\n", |
| 930 | j, g, out, correct, error); |
| 931 | } |
| 932 | } |
| 933 | |
| 934 | if (!silent) |
Matt Sarett | 96be908 | 2016-05-03 13:29:54 -0400 | [diff] [blame^] | 935 | printf("gamma %f: maximum 16-bit error %f\n", g, maxerr); |
Chris Craik | ca2bf81 | 2013-07-29 15:28:30 -0700 | [diff] [blame] | 936 | } |
| 937 | |
| 938 | return 0; |
| 939 | } |
| 940 | |
| 941 | /**************************** VALIDATION TESTS ********************************/ |
| 942 | /* Various validation routines are included herein, they require some |
| 943 | * definition for png_warning and png_error, seetings of VALIDATION: |
| 944 | * |
| 945 | * 1: validates the ASCII to floating point conversions |
| 946 | * 2: validates png_muldiv |
| 947 | * 3: accuracy test of fixed point gamma tables |
| 948 | */ |
| 949 | |
| 950 | /* The following COUNT (10^8) takes about 1 hour on a 1GHz Pentium IV |
| 951 | * processor. |
| 952 | */ |
| 953 | #define COUNT 1000000000 |
| 954 | |
| 955 | int main(int argc, char **argv) |
| 956 | { |
| 957 | int count = COUNT; |
| 958 | |
| 959 | while (argc > 1) |
| 960 | { |
| 961 | if (argc > 2 && strcmp(argv[1], "-c") == 0) |
| 962 | { |
| 963 | count = atoi(argv[2]); |
| 964 | argc -= 2; |
| 965 | argv += 2; |
| 966 | } |
| 967 | |
| 968 | else if (strcmp(argv[1], "-v") == 0) |
| 969 | { |
| 970 | ++verbose; |
| 971 | --argc; |
| 972 | ++argv; |
| 973 | } |
| 974 | |
| 975 | else |
| 976 | break; |
| 977 | } |
| 978 | |
| 979 | if (count > 0 && argc > 1) |
| 980 | { |
| 981 | if (strcmp(argv[1], "ascii") == 0) |
| 982 | return validation_ascii_to_fp(count, argc-1, argv+1); |
| 983 | else if (strcmp(argv[1], "checkfp") == 0) |
| 984 | return validation_checkfp(count, argc-1, argv+1); |
| 985 | else if (strcmp(argv[1], "muldiv") == 0) |
| 986 | return validation_muldiv(count, argc-1, argv+1); |
| 987 | else if (strcmp(argv[1], "gamma") == 0) |
| 988 | return validation_gamma(argc-1, argv+1); |
| 989 | } |
| 990 | |
| 991 | /* Bad argument: */ |
| 992 | fprintf(stderr, |
| 993 | "usage: tarith [-v] [-c count] {ascii,muldiv,gamma} [args]\n"); |
| 994 | fprintf(stderr, " arguments: ascii [-a (all results)] [-e error%%]\n"); |
| 995 | fprintf(stderr, " checkfp [-l max-number-chars]\n"); |
| 996 | fprintf(stderr, " muldiv\n"); |
| 997 | fprintf(stderr, " gamma -s (silent) -g (only gamma; no log)\n"); |
| 998 | return 1; |
| 999 | } |