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janet/junkyard/strtod_test.c

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2017-12-08 20:57:02 +00:00
/*
* Copyright (c) 2017 Calvin Rose
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
/* Use a custom double parser instead of libc's strtod for better portability
* and control. Also, uses a less strict rounding method than ieee to not incur
* the cost of 4000 loc and dependence on arbitary precision arithmetic. There
* is no plan to use arbitrary precision arithmetic for parsing numbers, and a
* formal rounding mode has yet to be chosen (round towards 0 seems
* reasonable).
*
* This version has been modified for much greater flexibility in parsing, such
* as choosing the radix, supporting integer output, and returning DstValues
* directly.
*
* Numbers are of the form [-+]R[rR]I.F[eE&][-+]X where R is the radix, I is
* the integer part, F is the fractional part, and X is the exponent. All
* signs, radix, decimal point, fractional part, and exponent can be ommited.
* The number will be considered and integer if the there is no decimal point
* and no exponent. Any number greater the 2^32-1 or less than -(2^32) will be
* coerced to a double. If there is an error, the function dst_scan_number will
* return a dst nil. The radix is assumed to be 10 if omitted, and the E
* separator for the exponent can only be used when the radix is 10. This is
* because E is a vaid digit in bases 15 or greater. For bases greater than 10,
* the letters are used as digitis. A through Z correspond to the digits 10
* through 35, and the lowercase letters have the same values. The radix number
* is always in base 10. For example, a hexidecimal number could be written
* '16rdeadbeef'. dst_scan_number also supports some c style syntax for
* hexidecimal literals. The previous number could also be written
* '0xdeadbeef'. Note that in this case, the number will actually be a double
* as it will not fit in the range for a signed 32 bit integer. The string
* '0xbeef' would parse to an integer as it is in the range of an int32_t. */
#include "unit.h"
#include <dst/dst.h>
#include <math.h>
DstValue dst_scan_number(const uint8_t *str, int32_t len);
const char *valid_test_strs[] = {
"0",
"-0.0",
"+0",
"123",
"-123",
"aaaaaa",
"+a123",
"0.12312",
"89.12312",
"-123.01231",
"123e10",
"1203412347981232379183.13013248723478932478923478e12",
"120341234798123237918313013248723478932478923478",
"999_999_999_999",
"8r777",
"",
"----",
" ",
"--123",
"0xff",
"0xff.f",
"0xff&-1",
"0xfefefe",
"1926.4823e11",
"0xff_ff_ff_ff",
"0xff_ff_ff_ff_ff_ff",
"2r1010",
"2r10101010001101",
"123a",
"0.1e510",
"4.123123e-308",
"4.123123e-320",
"1e-308",
"1e-309",
"9e-308",
"9e-309",
"919283691283e-309",
"9999e302",
"123.12312.123",
"90.e0.1",
"90.e1",
".e1"
};
int main() {
dst_init();
unsigned i;
for (i = 0; i < (sizeof(valid_test_strs) / sizeof(void *)); i++) {
DstValue out;
double refout;
const uint8_t *str = (const uint8_t *) valid_test_strs[i];
int32_t len = 0; while (str[len]) len++;
refout = strtod(valid_test_strs[i], NULL);
out = dst_scan_number(str, len);
dst_puts(dst_formatc("literal: %s, out: %v, refout: %v\n",
valid_test_strs[i], out, dst_wrap_real(refout)));
}
uint64_t x = 0x07FFFFFFFFFFFFFF;
uint64_t y = 36;
printf("%llu, %llu\n", x, (x * y) / y);
}