1000 lines
28 KiB
C
1000 lines
28 KiB
C
|
|
/* tarith.c
|
|
*
|
|
* Copyright (c) 2011-2013 John Cunningham Bowler
|
|
*
|
|
* Last changed in libpng 1.6.0 [February 14, 2013]
|
|
*
|
|
* This code is released under the libpng license.
|
|
* For conditions of distribution and use, see the disclaimer
|
|
* and license in png.h
|
|
*
|
|
* Test internal arithmetic functions of libpng.
|
|
*
|
|
* This code must be linked against a math library (-lm), but does not require
|
|
* libpng or zlib to work. Because it includes the complete source of 'png.c'
|
|
* it tests the code with whatever compiler options are used to build it.
|
|
* Changing these options can substantially change the errors in the
|
|
* calculations that the compiler chooses!
|
|
*/
|
|
#define _POSIX_SOURCE 1
|
|
#define _ISOC99_SOURCE 1
|
|
|
|
/* Obtain a copy of the code to be tested (plus other things), disabling
|
|
* stuff that is not required.
|
|
*/
|
|
#include <math.h>
|
|
#include <stdlib.h>
|
|
#include <ctype.h>
|
|
#include <string.h>
|
|
#include <assert.h>
|
|
|
|
#include "../../pngpriv.h"
|
|
|
|
#define png_error png_warning
|
|
|
|
void png_warning(png_const_structrp png_ptr, png_const_charp msg)
|
|
{
|
|
fprintf(stderr, "validation: %s\n", msg);
|
|
}
|
|
|
|
#define png_fixed_error png_fixed_warning
|
|
|
|
void png_fixed_warning(png_const_structrp png_ptr, png_const_charp msg)
|
|
{
|
|
fprintf(stderr, "overflow in: %s\n", msg);
|
|
}
|
|
|
|
#define png_set_error_fn(pp, ep, efp, wfp) ((void)0)
|
|
#define png_malloc(pp, s) malloc(s)
|
|
#define png_malloc_warn(pp, s) malloc(s)
|
|
#define png_malloc_base(pp, s) malloc(s)
|
|
#define png_calloc(pp, s) calloc(1, (s))
|
|
#define png_free(pp, s) free(s)
|
|
|
|
#define png_safecat(b, sb, pos, str) (pos)
|
|
#define png_format_number(start, end, format, number) (start)
|
|
|
|
#define crc32(crc, pp, s) (crc)
|
|
#define inflateReset(zs) Z_OK
|
|
|
|
#define png_create_struct(type) (0)
|
|
#define png_destroy_struct(pp) ((void)0)
|
|
#define png_create_struct_2(type, m, mm) (0)
|
|
#define png_destroy_struct_2(pp, f, mm) ((void)0)
|
|
|
|
#undef PNG_SIMPLIFIED_READ_SUPPORTED
|
|
#undef PNG_SIMPLIFIED_WRITE_SUPPORTED
|
|
#undef PNG_USER_MEM_SUPPORTED
|
|
|
|
#include "../../png.c"
|
|
|
|
/* Validate ASCII to fp routines. */
|
|
static int verbose = 0;
|
|
|
|
int validation_ascii_to_fp(int count, int argc, char **argv)
|
|
{
|
|
int showall = 0;
|
|
double max_error=2; /* As a percentage error-in-last-digit/.5 */
|
|
double max_error_abs=17; /* Used when precision is DBL_DIG */
|
|
double max = 0;
|
|
double max_abs = 0;
|
|
double test = 0; /* Important to test this. */
|
|
int precision = 5;
|
|
int nonfinite = 0;
|
|
int finite = 0;
|
|
int ok = 0;
|
|
int failcount = 0;
|
|
int minorarith = 0;
|
|
|
|
while (--argc > 0)
|
|
if (strcmp(*++argv, "-a") == 0)
|
|
showall = 1;
|
|
else if (strcmp(*argv, "-e") == 0 && argc > 0)
|
|
{
|
|
--argc;
|
|
max_error = atof(*++argv);
|
|
}
|
|
else if (strcmp(*argv, "-E") == 0 && argc > 0)
|
|
{
|
|
--argc;
|
|
max_error_abs = atof(*++argv);
|
|
}
|
|
else
|
|
{
|
|
fprintf(stderr, "unknown argument %s\n", *argv);
|
|
return 1;
|
|
}
|
|
|
|
do
|
|
{
|
|
png_size_t index;
|
|
int state, failed = 0;
|
|
char buffer[64];
|
|
|
|
if (isfinite(test))
|
|
++finite;
|
|
else
|
|
++nonfinite;
|
|
|
|
if (verbose)
|
|
fprintf(stderr, "%.*g %d\n", DBL_DIG, test, precision);
|
|
|
|
/* Check for overflow in the buffer by setting a marker. */
|
|
memset(buffer, 71, sizeof buffer);
|
|
|
|
png_ascii_from_fp(0, buffer, precision+10, test, precision);
|
|
|
|
/* Allow for a three digit exponent, this stuff will fail if
|
|
* the exponent is bigger than this!
|
|
*/
|
|
if (buffer[precision+7] != 71)
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test,
|
|
precision, buffer, (unsigned long)strlen(buffer));
|
|
failed = 1;
|
|
}
|
|
|
|
/* Following are used for the number parser below and must be
|
|
* initialized to zero.
|
|
*/
|
|
state = 0;
|
|
index = 0;
|
|
if (!isfinite(test))
|
|
{
|
|
/* Expect 'inf' */
|
|
if (test >= 0 && strcmp(buffer, "inf") ||
|
|
test < 0 && strcmp(buffer, "-inf"))
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test,
|
|
precision, buffer);
|
|
failed = 1;
|
|
}
|
|
}
|
|
else if (!png_check_fp_number(buffer, precision+10, &state, &index) ||
|
|
buffer[index] != 0)
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test,
|
|
precision, buffer, buffer[index]);
|
|
failed = 1;
|
|
}
|
|
else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0))
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s' but negative value not so reported\n",
|
|
test, precision, buffer);
|
|
failed = 1;
|
|
assert(!PNG_FP_IS_ZERO(state));
|
|
assert(!PNG_FP_IS_POSITIVE(state));
|
|
}
|
|
else if (PNG_FP_IS_ZERO(state) && !(test == 0))
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s' but zero value not so reported\n",
|
|
test, precision, buffer);
|
|
failed = 1;
|
|
assert(!PNG_FP_IS_NEGATIVE(state));
|
|
assert(!PNG_FP_IS_POSITIVE(state));
|
|
}
|
|
else if (PNG_FP_IS_POSITIVE(state) && !(test > 0))
|
|
{
|
|
fprintf(stderr, "%g[%d] -> '%s' but postive value not so reported\n",
|
|
test, precision, buffer);
|
|
failed = 1;
|
|
assert(!PNG_FP_IS_NEGATIVE(state));
|
|
assert(!PNG_FP_IS_ZERO(state));
|
|
}
|
|
else
|
|
{
|
|
/* Check the result against the original. */
|
|
double out = atof(buffer);
|
|
double change = fabs((out - test)/test);
|
|
double allow = .5/pow(10,
|
|
(precision >= DBL_DIG) ? DBL_DIG-1 : precision-1);
|
|
|
|
/* NOTE: if you hit this error case are you compiling with gcc
|
|
* and -O0? Try -O2 - the errors can accumulate if the FP
|
|
* code above is not optimized and may drift outside the .5 in
|
|
* DBL_DIG allowed. In any case a small number of errors may
|
|
* occur (very small ones - 1 or 2%) because of rounding in the
|
|
* calculations, either in the conversion API or in atof.
|
|
*/
|
|
if (change >= allow && (isfinite(out) ||
|
|
fabs(test/DBL_MAX) <= 1-allow))
|
|
{
|
|
double percent = (precision >= DBL_DIG) ? max_error_abs : max_error;
|
|
double allowp = (change-allow)*100/allow;
|
|
|
|
if (precision >= DBL_DIG)
|
|
{
|
|
if (max_abs < allowp) max_abs = allowp;
|
|
}
|
|
|
|
else
|
|
{
|
|
if (max < allowp) max = allowp;
|
|
}
|
|
|
|
if (showall || allowp >= percent)
|
|
{
|
|
fprintf(stderr,
|
|
"%.*g[%d] -> '%s' -> %.*g number changed (%g > %g (%d%%))\n",
|
|
DBL_DIG, test, precision, buffer, DBL_DIG, out, change, allow,
|
|
(int)round(allowp));
|
|
failed = 1;
|
|
}
|
|
else
|
|
++minorarith;
|
|
}
|
|
}
|
|
|
|
if (failed)
|
|
++failcount;
|
|
else
|
|
++ok;
|
|
|
|
skip:
|
|
/* Generate a new number and precision. */
|
|
precision = rand();
|
|
if (precision & 1) test = -test;
|
|
precision >>= 1;
|
|
|
|
/* Generate random numbers. */
|
|
if (test == 0 || !isfinite(test))
|
|
test = precision+1;
|
|
else
|
|
{
|
|
/* Derive the exponent from the previous rand() value. */
|
|
int exponent = precision % (DBL_MAX_EXP - DBL_MIN_EXP) + DBL_MIN_EXP;
|
|
int tmp;
|
|
test = frexp(test * rand(), &tmp);
|
|
test = ldexp(test, exponent);
|
|
precision >>= 8; /* arbitrary */
|
|
}
|
|
|
|
/* This limits the precision to 32 digits, enough for standard
|
|
* IEEE implementations which have at most 15 digits.
|
|
*/
|
|
precision = (precision & 0x1f) + 1;
|
|
}
|
|
while (--count);
|
|
|
|
printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor "
|
|
"arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith);
|
|
printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs);
|
|
printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Observe that valid FP numbers have the forms listed in the PNG extensions
|
|
* specification:
|
|
*
|
|
* [+,-]{integer,integer.fraction,.fraction}[{e,E}[+,-]integer]
|
|
*
|
|
* Test each of these in turn, including invalid cases.
|
|
*/
|
|
typedef enum checkfp_state
|
|
{
|
|
start, fraction, exponent, states
|
|
} checkfp_state;
|
|
|
|
/* The characters (other than digits) that characterize the states: */
|
|
static const char none[] = "";
|
|
static const char hexdigits[16] = "0123456789ABCDEF";
|
|
|
|
static const struct
|
|
{
|
|
const char *start; /* Characters valid at the start */
|
|
const char *end; /* Valid characters that end the state */
|
|
const char *tests; /* Characters to test after 2 digits seen */
|
|
}
|
|
state_characters[states] =
|
|
{
|
|
/* start: */ { "+-.", ".eE", "+-.e*0369" },
|
|
/* fraction: */ { none, "eE", "+-.E#0147" },
|
|
/* exponent: */ { "+-", none, "+-.eE^0258" }
|
|
};
|
|
|
|
typedef struct
|
|
{
|
|
char number[1024]; /* Buffer for number being tested */
|
|
int limit; /* Command line limit */
|
|
int verbose; /* Shadows global variable */
|
|
int ctimes; /* Number of numbers tested */
|
|
int cmillions; /* Count of millions of numbers */
|
|
int cinvalid; /* Invalid strings checked */
|
|
int cnoaccept; /* Characters not accepted */
|
|
}
|
|
checkfp_command;
|
|
|
|
typedef struct
|
|
{
|
|
int cnumber; /* Index into number string */
|
|
checkfp_state check_state; /* Current number state */
|
|
int at_start; /* At start (first character) of state */
|
|
int cdigits_in_state; /* Digits seen in that state */
|
|
int limit; /* Limit on same for checking all chars */
|
|
int state; /* Current parser state */
|
|
int is_negative; /* Number is negative */
|
|
int is_zero; /* Number is (still) zero */
|
|
int number_was_valid; /* Previous character validity */
|
|
}
|
|
checkfp_control;
|
|
|
|
static int check_all_characters(checkfp_command *co, checkfp_control c);
|
|
|
|
static int check_some_characters(checkfp_command *co, checkfp_control c,
|
|
const char *tests);
|
|
|
|
static int check_one_character(checkfp_command *co, checkfp_control c, int ch)
|
|
{
|
|
/* Test this character (ch) to ensure the parser does the correct thing.
|
|
*/
|
|
png_size_t index = 0;
|
|
const char test = (char)ch;
|
|
const int number_is_valid = png_check_fp_number(&test, 1, &c.state, &index);
|
|
const int character_accepted = (index == 1);
|
|
|
|
if (c.check_state != exponent && isdigit(ch) && ch != '0')
|
|
c.is_zero = 0;
|
|
|
|
if (c.check_state == start && c.at_start && ch == '-')
|
|
c.is_negative = 1;
|
|
|
|
if (isprint(ch))
|
|
co->number[c.cnumber++] = (char)ch;
|
|
else
|
|
{
|
|
co->number[c.cnumber++] = '<';
|
|
co->number[c.cnumber++] = hexdigits[(ch >> 4) & 0xf];
|
|
co->number[c.cnumber++] = hexdigits[ch & 0xf];
|
|
co->number[c.cnumber++] = '>';
|
|
}
|
|
co->number[c.cnumber] = 0;
|
|
|
|
if (co->verbose > 1)
|
|
fprintf(stderr, "%s\n", co->number);
|
|
|
|
if (++(co->ctimes) == 1000000)
|
|
{
|
|
if (co->verbose == 1)
|
|
fputc('.', stderr);
|
|
co->ctimes = 0;
|
|
++(co->cmillions);
|
|
}
|
|
|
|
if (!number_is_valid)
|
|
++(co->cinvalid);
|
|
|
|
if (!character_accepted)
|
|
++(co->cnoaccept);
|
|
|
|
/* This should never fail (it's a serious bug if it does): */
|
|
if (index != 0 && index != 1)
|
|
{
|
|
fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number,
|
|
(unsigned long)index);
|
|
return 0;
|
|
}
|
|
|
|
/* Validate the new state, note that the PNG_FP_IS_ macros all return
|
|
* false unless the number is valid.
|
|
*/
|
|
if (PNG_FP_IS_NEGATIVE(c.state) !=
|
|
(number_is_valid && !c.is_zero && c.is_negative))
|
|
{
|
|
fprintf(stderr, "%s: negative when it is not\n", co->number);
|
|
return 0;
|
|
}
|
|
|
|
if (PNG_FP_IS_ZERO(c.state) != (number_is_valid && c.is_zero))
|
|
{
|
|
fprintf(stderr, "%s: zero when it is not\n", co->number);
|
|
return 0;
|
|
}
|
|
|
|
if (PNG_FP_IS_POSITIVE(c.state) !=
|
|
(number_is_valid && !c.is_zero && !c.is_negative))
|
|
{
|
|
fprintf(stderr, "%s: positive when it is not\n", co->number);
|
|
return 0;
|
|
}
|
|
|
|
/* Testing a digit */
|
|
if (isdigit(ch))
|
|
{
|
|
if (!character_accepted)
|
|
{
|
|
fprintf(stderr, "%s: digit '%c' not accepted\n", co->number, ch);
|
|
return 0;
|
|
}
|
|
|
|
if (!number_is_valid)
|
|
{
|
|
fprintf(stderr, "%s: saw a digit (%c) but number not valid\n",
|
|
co->number, ch);
|
|
return 0;
|
|
}
|
|
|
|
++c.cdigits_in_state;
|
|
c.at_start = 0;
|
|
c.number_was_valid = 1;
|
|
|
|
/* Continue testing characters in this state. Either test all of
|
|
* them or, if we have already seen one digit in this state, just test a
|
|
* limited set.
|
|
*/
|
|
if (c.cdigits_in_state < 1)
|
|
return check_all_characters(co, c);
|
|
|
|
else
|
|
return check_some_characters(co, c,
|
|
state_characters[c.check_state].tests);
|
|
}
|
|
|
|
/* A non-digit; is it allowed here? */
|
|
else if (((ch == '+' || ch == '-') && c.check_state != fraction &&
|
|
c.at_start) ||
|
|
(ch == '.' && c.check_state == start) ||
|
|
((ch == 'e' || ch == 'E') && c.number_was_valid &&
|
|
c.check_state != exponent))
|
|
{
|
|
if (!character_accepted)
|
|
{
|
|
fprintf(stderr, "%s: character '%c' not accepted\n", co->number, ch);
|
|
return 0;
|
|
}
|
|
|
|
/* The number remains valid after start of fraction but nowhere else. */
|
|
if (number_is_valid && (c.check_state != start || ch != '.'))
|
|
{
|
|
fprintf(stderr, "%s: saw a non-digit (%c) but number valid\n",
|
|
co->number, ch);
|
|
return 0;
|
|
}
|
|
|
|
c.number_was_valid = number_is_valid;
|
|
|
|
/* Check for a state change. When changing to 'fraction' if the number
|
|
* is valid at this point set the at_start to false to allow an exponent
|
|
* 'e' to come next.
|
|
*/
|
|
if (c.check_state == start && ch == '.')
|
|
{
|
|
c.check_state = fraction;
|
|
c.at_start = !number_is_valid;
|
|
c.cdigits_in_state = 0;
|
|
c.limit = co->limit;
|
|
return check_all_characters(co, c);
|
|
}
|
|
|
|
else if (c.check_state < exponent && (ch == 'e' || ch == 'E'))
|
|
{
|
|
c.check_state = exponent;
|
|
c.at_start = 1;
|
|
c.cdigits_in_state = 0;
|
|
c.limit = co->limit;
|
|
return check_all_characters(co, c);
|
|
}
|
|
|
|
/* Else it was a sign, and the state doesn't change. */
|
|
else
|
|
{
|
|
if (ch != '-' && ch != '+')
|
|
{
|
|
fprintf(stderr, "checkfp: internal error (1)\n");
|
|
return 0;
|
|
}
|
|
|
|
c.at_start = 0;
|
|
return check_all_characters(co, c);
|
|
}
|
|
}
|
|
|
|
/* Testing an invalid character */
|
|
else
|
|
{
|
|
if (character_accepted)
|
|
{
|
|
fprintf(stderr, "%s: character '%c' [0x%.2x] accepted\n", co->number,
|
|
ch, ch);
|
|
return 0;
|
|
}
|
|
|
|
if (number_is_valid != c.number_was_valid)
|
|
{
|
|
fprintf(stderr,
|
|
"%s: character '%c' [0x%.2x] changed number validity\n", co->number,
|
|
ch, ch);
|
|
return 0;
|
|
}
|
|
|
|
/* Do nothing - the parser has stuck; return success and keep going with
|
|
* the next character.
|
|
*/
|
|
}
|
|
|
|
/* Successful return (the caller will try the next character.) */
|
|
return 1;
|
|
}
|
|
|
|
static int check_all_characters(checkfp_command *co, checkfp_control c)
|
|
{
|
|
int ch;
|
|
|
|
if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch)
|
|
{
|
|
if (!check_one_character(co, c, ch))
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int check_some_characters(checkfp_command *co, checkfp_control c,
|
|
const char *tests)
|
|
{
|
|
int i;
|
|
|
|
--(c.limit);
|
|
|
|
if (c.cnumber+4 < sizeof co->number && c.limit >= 0)
|
|
{
|
|
if (c.limit > 0) for (i=0; tests[i]; ++i)
|
|
{
|
|
if (!check_one_character(co, c, tests[i]))
|
|
return 0;
|
|
}
|
|
|
|
/* At the end check all the characters. */
|
|
else
|
|
return check_all_characters(co, c);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
int validation_checkfp(int count, int argc, char **argv)
|
|
{
|
|
int result;
|
|
checkfp_command command;
|
|
checkfp_control control;
|
|
|
|
command.number[0] = 0;
|
|
command.limit = 3;
|
|
command.verbose = verbose;
|
|
command.ctimes = 0;
|
|
command.cmillions = 0;
|
|
command.cinvalid = 0;
|
|
command.cnoaccept = 0;
|
|
|
|
while (--argc > 0)
|
|
{
|
|
++argv;
|
|
if (argc > 1 && strcmp(*argv, "-l") == 0)
|
|
{
|
|
--argc;
|
|
command.limit = atoi(*++argv);
|
|
}
|
|
|
|
else
|
|
{
|
|
fprintf(stderr, "unknown argument %s\n", *argv);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
control.cnumber = 0;
|
|
control.check_state = start;
|
|
control.at_start = 1;
|
|
control.cdigits_in_state = 0;
|
|
control.limit = command.limit;
|
|
control.state = 0;
|
|
control.is_negative = 0;
|
|
control.is_zero = 1;
|
|
control.number_was_valid = 0;
|
|
|
|
result = check_all_characters(&command, control);
|
|
|
|
printf("checkfp: %s: checked %d,%.3d,%.3d,%.3d strings (%d invalid)\n",
|
|
result ? "pass" : "FAIL", command.cmillions / 1000,
|
|
command.cmillions % 1000, command.ctimes / 1000, command.ctimes % 1000,
|
|
command.cinvalid);
|
|
|
|
return result;
|
|
}
|
|
|
|
int validation_muldiv(int count, int argc, char **argv)
|
|
{
|
|
int tested = 0;
|
|
int overflow = 0;
|
|
int error = 0;
|
|
int error64 = 0;
|
|
int passed = 0;
|
|
int randbits = 0;
|
|
png_uint_32 randbuffer;
|
|
png_fixed_point a;
|
|
png_int_32 times, div;
|
|
|
|
while (--argc > 0)
|
|
{
|
|
fprintf(stderr, "unknown argument %s\n", *++argv);
|
|
return 1;
|
|
}
|
|
|
|
/* Find out about the random number generator. */
|
|
randbuffer = RAND_MAX;
|
|
while (randbuffer != 0) ++randbits, randbuffer >>= 1;
|
|
printf("Using random number generator that makes %d bits\n", randbits);
|
|
for (div=0; div<32; div += randbits)
|
|
randbuffer = (randbuffer << randbits) ^ rand();
|
|
|
|
a = 0;
|
|
times = div = 0;
|
|
do
|
|
{
|
|
png_fixed_point result;
|
|
/* NOTE: your mileage may vary, a type is required below that can
|
|
* hold 64 bits or more, if floating point is used a 64 bit or
|
|
* better mantissa is required.
|
|
*/
|
|
long long int fp, fpround;
|
|
unsigned long hi, lo;
|
|
int ok;
|
|
|
|
/* Check the values, png_64bit_product can only handle positive
|
|
* numbers, so correct for that here.
|
|
*/
|
|
{
|
|
long u1, u2;
|
|
int n = 0;
|
|
if (a < 0) u1 = -a, n = 1; else u1 = a;
|
|
if (times < 0) u2 = -times, n = !n; else u2 = times;
|
|
png_64bit_product(u1, u2, &hi, &lo);
|
|
if (n)
|
|
{
|
|
/* -x = ~x+1 */
|
|
lo = ((~lo) + 1) & 0xffffffff;
|
|
hi = ~hi;
|
|
if (lo == 0) ++hi;
|
|
}
|
|
}
|
|
|
|
fp = a;
|
|
fp *= times;
|
|
if ((fp & 0xffffffff) != lo || ((fp >> 32) & 0xffffffff) != hi)
|
|
{
|
|
fprintf(stderr, "png_64bit_product %d * %d -> %lx|%.8lx not %llx\n",
|
|
a, times, hi, lo, fp);
|
|
++error64;
|
|
}
|
|
|
|
if (div != 0)
|
|
{
|
|
/* Round - this is C round to zero. */
|
|
if ((fp < 0) != (div < 0))
|
|
fp -= div/2;
|
|
else
|
|
fp += div/2;
|
|
|
|
fp /= div;
|
|
fpround = fp;
|
|
/* Assume 2's complement here: */
|
|
ok = fpround <= PNG_UINT_31_MAX &&
|
|
fpround >= -1-(long long int)PNG_UINT_31_MAX;
|
|
if (!ok) ++overflow;
|
|
}
|
|
else
|
|
ok = 0, ++overflow, fpround = fp/*misleading*/;
|
|
|
|
if (verbose)
|
|
fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div,
|
|
fp, ok ? "ok" : "overflow");
|
|
|
|
++tested;
|
|
if (png_muldiv(&result, a, times, div) != ok)
|
|
{
|
|
++error;
|
|
if (ok)
|
|
fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a,
|
|
times, div, fp);
|
|
else
|
|
fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a,
|
|
times, div, result, fp);
|
|
}
|
|
else if (ok && result != fpround)
|
|
{
|
|
++error;
|
|
fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result,
|
|
fp);
|
|
}
|
|
else
|
|
++passed;
|
|
|
|
/* Generate three new values, this uses rand() and rand() only returns
|
|
* up to RAND_MAX.
|
|
*/
|
|
/* CRUDE */
|
|
a += times;
|
|
times += div;
|
|
div = randbuffer;
|
|
randbuffer = (randbuffer << randbits) ^ rand();
|
|
}
|
|
while (--count > 0);
|
|
|
|
printf("%d tests including %d overflows, %d passed, %d failed (%d 64 bit "
|
|
"errors)\n", tested, overflow, passed, error, error64);
|
|
return 0;
|
|
}
|
|
|
|
/* When FP is on this just becomes a speed test - compile without FP to get real
|
|
* validation.
|
|
*/
|
|
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
|
|
#define LN2 .000010576586617430806112933839 /* log(2)/65536 */
|
|
#define L2INV 94548.46219969910586572651 /* 65536/log(2) */
|
|
|
|
/* For speed testing, need the internal functions too: */
|
|
static png_uint_32 png_log8bit(unsigned x)
|
|
{
|
|
if (x > 0)
|
|
return (png_uint_32)floor(.5-log(x/255.)*L2INV);
|
|
|
|
return 0xffffffff;
|
|
}
|
|
|
|
static png_uint_32 png_log16bit(png_uint_32 x)
|
|
{
|
|
if (x > 0)
|
|
return (png_uint_32)floor(.5-log(x/65535.)*L2INV);
|
|
|
|
return 0xffffffff;
|
|
}
|
|
|
|
static png_uint_32 png_exp(png_uint_32 x)
|
|
{
|
|
return (png_uint_32)floor(.5 + exp(x * -LN2) * 0xffffffffU);
|
|
}
|
|
|
|
static png_byte png_exp8bit(png_uint_32 log)
|
|
{
|
|
return (png_byte)floor(.5 + exp(log * -LN2) * 255);
|
|
}
|
|
|
|
static png_uint_16 png_exp16bit(png_uint_32 log)
|
|
{
|
|
return (png_uint_16)floor(.5 + exp(log * -LN2) * 65535);
|
|
}
|
|
#endif /* FLOATING_ARITHMETIC */
|
|
|
|
int validation_gamma(int argc, char **argv)
|
|
{
|
|
double gamma[9] = { 2.2, 1.8, 1.52, 1.45, 1., 1/1.45, 1/1.52, 1/1.8, 1/2.2 };
|
|
double maxerr;
|
|
int i, silent=0, onlygamma=0;
|
|
|
|
/* Silence the output with -s, just test the gamma functions with -g: */
|
|
while (--argc > 0)
|
|
if (strcmp(*++argv, "-s") == 0)
|
|
silent = 1;
|
|
else if (strcmp(*argv, "-g") == 0)
|
|
onlygamma = 1;
|
|
else
|
|
{
|
|
fprintf(stderr, "unknown argument %s\n", *argv);
|
|
return 1;
|
|
}
|
|
|
|
if (!onlygamma)
|
|
{
|
|
/* First validate the log functions: */
|
|
maxerr = 0;
|
|
for (i=0; i<256; ++i)
|
|
{
|
|
double correct = -log(i/255.)/log(2.)*65536;
|
|
double error = png_log8bit(i) - correct;
|
|
|
|
if (i != 0 && fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
|
|
if (i == 0 && png_log8bit(i) != 0xffffffff ||
|
|
i != 0 && png_log8bit(i) != floor(correct+.5))
|
|
{
|
|
fprintf(stderr, "8 bit log error: %d: got %u, expected %f\n",
|
|
i, png_log8bit(i), correct);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("maximum 8 bit log error = %f\n", maxerr);
|
|
|
|
maxerr = 0;
|
|
for (i=0; i<65536; ++i)
|
|
{
|
|
double correct = -log(i/65535.)/log(2.)*65536;
|
|
double error = png_log16bit(i) - correct;
|
|
|
|
if (i != 0 && fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
|
|
if (i == 0 && png_log16bit(i) != 0xffffffff ||
|
|
i != 0 && png_log16bit(i) != floor(correct+.5))
|
|
{
|
|
if (error > .68) /* By experiment error is less than .68 */
|
|
{
|
|
fprintf(stderr, "16 bit log error: %d: got %u, expected %f"
|
|
" error: %f\n", i, png_log16bit(i), correct, error);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("maximum 16 bit log error = %f\n", maxerr);
|
|
|
|
/* Now exponentiations. */
|
|
maxerr = 0;
|
|
for (i=0; i<=0xfffff; ++i)
|
|
{
|
|
double correct = exp(-i/65536. * log(2.)) * (65536. * 65536);
|
|
double error = png_exp(i) - correct;
|
|
|
|
if (fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
if (fabs(error) > 1883) /* By experiment. */
|
|
{
|
|
fprintf(stderr, "32 bit exp error: %d: got %u, expected %f"
|
|
" error: %f\n", i, png_exp(i), correct, error);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("maximum 32 bit exp error = %f\n", maxerr);
|
|
|
|
maxerr = 0;
|
|
for (i=0; i<=0xfffff; ++i)
|
|
{
|
|
double correct = exp(-i/65536. * log(2.)) * 255;
|
|
double error = png_exp8bit(i) - correct;
|
|
|
|
if (fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
if (fabs(error) > .50002) /* By experiment */
|
|
{
|
|
fprintf(stderr, "8 bit exp error: %d: got %u, expected %f"
|
|
" error: %f\n", i, png_exp8bit(i), correct, error);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("maximum 8 bit exp error = %f\n", maxerr);
|
|
|
|
maxerr = 0;
|
|
for (i=0; i<=0xfffff; ++i)
|
|
{
|
|
double correct = exp(-i/65536. * log(2.)) * 65535;
|
|
double error = png_exp16bit(i) - correct;
|
|
|
|
if (fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
if (fabs(error) > .524) /* By experiment */
|
|
{
|
|
fprintf(stderr, "16 bit exp error: %d: got %u, expected %f"
|
|
" error: %f\n", i, png_exp16bit(i), correct, error);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("maximum 16 bit exp error = %f\n", maxerr);
|
|
} /* !onlygamma */
|
|
|
|
/* Test the overall gamma correction. */
|
|
for (i=0; i<9; ++i)
|
|
{
|
|
unsigned j;
|
|
double g = gamma[i];
|
|
png_fixed_point gfp = floor(g * PNG_FP_1 + .5);
|
|
|
|
if (!silent)
|
|
printf("Test gamma %f\n", g);
|
|
|
|
maxerr = 0;
|
|
for (j=0; j<256; ++j)
|
|
{
|
|
double correct = pow(j/255., g) * 255;
|
|
png_byte out = png_gamma_8bit_correct(j, gfp);
|
|
double error = out - correct;
|
|
|
|
if (fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
if (out != floor(correct+.5))
|
|
{
|
|
fprintf(stderr, "8bit %d ^ %f: got %d expected %f error %f\n",
|
|
j, g, out, correct, error);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("gamma %f: maximum 8 bit error %f\n", g, maxerr);
|
|
|
|
maxerr = 0;
|
|
for (j=0; j<65536; ++j)
|
|
{
|
|
double correct = pow(j/65535., g) * 65535;
|
|
png_uint_16 out = png_gamma_16bit_correct(j, gfp);
|
|
double error = out - correct;
|
|
|
|
if (fabs(error) > maxerr)
|
|
maxerr = fabs(error);
|
|
if (fabs(error) > 1.62)
|
|
{
|
|
fprintf(stderr, "16bit %d ^ %f: got %d expected %f error %f\n",
|
|
j, g, out, correct, error);
|
|
}
|
|
}
|
|
|
|
if (!silent)
|
|
printf("gamma %f: maximum 16 bit error %f\n", g, maxerr);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**************************** VALIDATION TESTS ********************************/
|
|
/* Various validation routines are included herein, they require some
|
|
* definition for png_warning and png_error, seetings of VALIDATION:
|
|
*
|
|
* 1: validates the ASCII to floating point conversions
|
|
* 2: validates png_muldiv
|
|
* 3: accuracy test of fixed point gamma tables
|
|
*/
|
|
|
|
/* The following COUNT (10^8) takes about 1 hour on a 1GHz Pentium IV
|
|
* processor.
|
|
*/
|
|
#define COUNT 1000000000
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int count = COUNT;
|
|
|
|
while (argc > 1)
|
|
{
|
|
if (argc > 2 && strcmp(argv[1], "-c") == 0)
|
|
{
|
|
count = atoi(argv[2]);
|
|
argc -= 2;
|
|
argv += 2;
|
|
}
|
|
|
|
else if (strcmp(argv[1], "-v") == 0)
|
|
{
|
|
++verbose;
|
|
--argc;
|
|
++argv;
|
|
}
|
|
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (count > 0 && argc > 1)
|
|
{
|
|
if (strcmp(argv[1], "ascii") == 0)
|
|
return validation_ascii_to_fp(count, argc-1, argv+1);
|
|
else if (strcmp(argv[1], "checkfp") == 0)
|
|
return validation_checkfp(count, argc-1, argv+1);
|
|
else if (strcmp(argv[1], "muldiv") == 0)
|
|
return validation_muldiv(count, argc-1, argv+1);
|
|
else if (strcmp(argv[1], "gamma") == 0)
|
|
return validation_gamma(argc-1, argv+1);
|
|
}
|
|
|
|
/* Bad argument: */
|
|
fprintf(stderr,
|
|
"usage: tarith [-v] [-c count] {ascii,muldiv,gamma} [args]\n");
|
|
fprintf(stderr, " arguments: ascii [-a (all results)] [-e error%%]\n");
|
|
fprintf(stderr, " checkfp [-l max-number-chars]\n");
|
|
fprintf(stderr, " muldiv\n");
|
|
fprintf(stderr, " gamma -s (silent) -g (only gamma; no log)\n");
|
|
return 1;
|
|
}
|