mirror of
https://github.com/DarkPlacesEngine/gmqcc.git
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542 lines
19 KiB
C
542 lines
19 KiB
C
/*
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* Copyright (C) 2012, 2013
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* Dale Weiler
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* Wolfgang Bumiller
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy of
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* this software and associated documentation files (the "Software"), to deal in
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* the Software without restriction, including without limitation the rights to
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* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
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* of the Software, and to permit persons to whom the Software is furnished to do
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* so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in all
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* copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*/
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#include <string.h>
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#include <stdlib.h>
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#include "gmqcc.h"
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void util_debug(const char *area, const char *ms, ...) {
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va_list va;
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if (!OPTS_OPTION_BOOL(OPTION_DEBUG))
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return;
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if (!strcmp(area, "MEM") && !OPTS_OPTION_BOOL(OPTION_MEMCHK))
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return;
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va_start(va, ms);
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con_out ("[%s] ", area);
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con_vout(ms, va);
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va_end (va);
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}
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/*
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* only required if big endian .. otherwise no need to swap
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* data.
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*/
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#if PLATFORM_BYTE_ORDER == GMQCC_BYTE_ORDER_BIG
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static GMQCC_INLINE void util_swap16(uint16_t *d, size_t l) {
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while (l--) {
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d[l] = (d[l] << 8) | (d[l] >> 8);
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}
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}
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static GMQCC_INLINE void util_swap32(uint32_t *d, size_t l) {
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while (l--) {
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uint32_t v;
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v = ((d[l] << 8) & 0xFF00FF00) | ((d[l] >> 8) & 0x00FF00FF);
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d[l] = (v << 16) | (v >> 16);
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}
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}
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/* Some strange system doesn't like constants that big, AND doesn't recognize an ULL suffix
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* so let's go the safe way
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*/
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static GMQCC_INLINE void util_swap64(uint32_t *d, size_t l) {
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/*
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while (l--) {
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uint64_t v;
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v = ((d[l] << 8) & 0xFF00FF00FF00FF00) | ((d[l] >> 8) & 0x00FF00FF00FF00FF);
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v = ((v << 16) & 0xFFFF0000FFFF0000) | ((v >> 16) & 0x0000FFFF0000FFFF);
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d[l] = (v << 32) | (v >> 32);
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}
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*/
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size_t i;
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for (i = 0; i < l; i += 2) {
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uint32_t v1 = d[i];
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d[i] = d[i+1];
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d[i+1] = v1;
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util_swap32(d+i, 2);
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}
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}
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#endif
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void util_endianswap(void *_data, size_t length, unsigned int typesize) {
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# if PLATFORM_BYTE_ORDER == -1 /* runtime check */
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if (*((char*)&typesize))
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return;
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#else
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/* prevent unused warnings */
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(void) _data;
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(void) length;
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(void) typesize;
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# if PLATFORM_BYTE_ORDER == GMQCC_BYTE_ORDER_LITTLE
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return;
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# else
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switch (typesize) {
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case 1: return;
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case 2:
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util_swap16((uint16_t*)_data, length>>1);
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return;
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case 4:
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util_swap32((uint32_t*)_data, length>>2);
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return;
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case 8:
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util_swap64((uint32_t*)_data, length>>3);
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return;
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default: exit(EXIT_FAILURE); /* please blow the fuck up! */
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}
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# endif
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#endif
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}
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/*
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* CRC algorithms vary in the width of the polynomial, the value of said polynomial,
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* the initial value used for the register, weather the bits of each byte are reflected
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* before being processed, weather the algorithm itself feeds input bytes through the
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* register or XORs them with a byte from one end and then straight into the table, as
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* well as (but not limited to the idea of reflected versions) where the final register
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* value becomes reversed, and finally weather the value itself is used to XOR the final
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* register value. AS such you can already imagine how painfully annoying CRCs are,
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* of course we stand to target Quake, which expects it's certian set of rules for proper
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* calculation of a CRC.
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*
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* In most traditional CRC algorithms on uses a reflected table driven method where a value
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* or register is reflected if it's bits are swapped around it's center. For example:
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* take the bits 0101 is the 4-bit reflection of 1010, and respectfully 0011 would be the
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* reflection of 1100. Quake however expects a NON-Reflected CRC on the output, but still
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* requires a final XOR on the values (0xFFFF and 0x0000) this is a standard CCITT CRC-16
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* which I respectfully as a programmer don't agree with.
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*
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* So now you know what we target, and why we target it, despite how unsettling it may seem
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* but those are what Quake seems to request.
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*/
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static const uint16_t util_crc16_table[] = {
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0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5,
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0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B,
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0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210,
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0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
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0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C,
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0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401,
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0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B,
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0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
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0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6,
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0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738,
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0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5,
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0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
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0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969,
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0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96,
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0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC,
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0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
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0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03,
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0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD,
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0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6,
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0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
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0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A,
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0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB,
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0xD10C, 0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1,
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0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
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0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C,
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0xE37F, 0xF35E, 0x02B1, 0x1290, 0x22F3, 0x32D2,
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0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB,
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0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
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0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447,
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0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8,
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0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2,
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0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
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0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9,
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0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827,
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0x18C0, 0x08E1, 0x3882, 0x28A3, 0xCB7D, 0xDB5C,
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0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
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0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0,
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0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D,
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0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07,
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0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
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0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA,
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0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74,
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0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
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};
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/* Non - Reflected */
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uint16_t util_crc16(uint16_t current, const char *k, size_t len) {
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register uint16_t h = current;
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for (; len; --len, ++k)
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h = util_crc16_table[(h>>8)^((unsigned char)*k)]^(h<<8);
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return h;
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}
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/* Reflective Varation (for reference) */
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#if 0
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uint16_t util_crc16(const char *k, int len, const short clamp) {
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register uint16_t h= (uint16_t)0xFFFFFFFF;
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for (; len; --len, ++k)
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h = util_crc16_table[(h^((unsigned char)*k))&0xFF]^(h>>8);
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return (~h)%clamp;
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}
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#endif
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size_t util_strtocmd(const char *in, char *out, size_t outsz) {
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size_t sz = 1;
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for (; *in && sz < outsz; ++in, ++out, ++sz)
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*out = (*in == '-') ? '_' : (util_isalpha(*in) && !util_isupper(*in)) ? *in + 'A' - 'a': *in;
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*out = 0;
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return sz-1;
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}
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size_t util_strtononcmd(const char *in, char *out, size_t outsz) {
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size_t sz = 1;
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for (; *in && sz < outsz; ++in, ++out, ++sz)
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*out = (*in == '_') ? '-' : (util_isalpha(*in) && util_isupper(*in)) ? *in + 'a' - 'A' : *in;
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*out = 0;
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return sz-1;
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}
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/*
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* Portable implementation of vasprintf/asprintf. Assumes vsnprintf
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* exists, otherwise compiler error.
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*
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* TODO: fix for MSVC ....
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*/
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int util_vasprintf(char **dat, const char *fmt, va_list args) {
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int ret;
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int len;
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char *tmp = NULL;
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/*
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* For visuals tido _vsnprintf doesn't tell you the length of a
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* formatted string if it overflows. However there is a MSVC
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* intrinsic (which is documented wrong) called _vcsprintf which
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* will return the required amount to allocate.
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*/
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#ifdef _MSC_VER
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if ((len = _vscprintf(fmt, args)) < 0) {
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*dat = NULL;
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return -1;
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}
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tmp = (char*)mem_a(len + 1);
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if ((ret = _vsnprintf_s(tmp, len+1, len+1, fmt, args)) != len) {
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mem_d(tmp);
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*dat = NULL;
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return -1;
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}
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*dat = tmp;
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return len;
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#else
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/*
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* For everything else we have a decent conformint vsnprintf that
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* returns the number of bytes needed. We give it a try though on
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* a short buffer, since efficently speaking, it could be nice to
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* above a second vsnprintf call.
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*/
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char buf[128];
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va_list cpy;
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va_copy(cpy, args);
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len = vsnprintf(buf, sizeof(buf), fmt, cpy);
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va_end (cpy);
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if (len < (int)sizeof(buf)) {
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*dat = util_strdup(buf);
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return len;
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}
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/* not large enough ... */
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tmp = (char*)mem_a(len + 1);
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if ((ret = vsnprintf(tmp, len + 1, fmt, args)) != len) {
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mem_d(tmp);
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*dat = NULL;
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return -1;
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}
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*dat = tmp;
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return len;
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#endif
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}
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int util_asprintf(char **ret, const char *fmt, ...) {
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va_list args;
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int read;
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va_start(args, fmt);
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read = util_vasprintf(ret, fmt, args);
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va_end (args);
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return read;
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}
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/*
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* These are various re-implementations (wrapping the real ones) of
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* string functions that MSVC consideres unsafe. We wrap these up and
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* use the safe varations on MSVC.
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*/
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#ifdef _MSC_VER
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static char **util_strerror_allocated() {
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static char **data = NULL;
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return data;
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}
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static void util_strerror_cleanup(void) {
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size_t i;
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char **data = util_strerror_allocated();
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for (i = 0; i < vec_size(data); i++)
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mem_d(data[i]);
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vec_free(data);
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}
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const char *util_strerror(int num) {
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char *allocated = NULL;
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static bool install = false;
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static size_t tries = 0;
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char **vector = util_strerror_allocated();
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/* try installing cleanup handler */
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while (!install) {
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if (tries == 32)
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return "(unknown)";
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install = !atexit(&util_strerror_cleanup);
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tries ++;
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}
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allocated = (char*)mem_a(4096); /* A page must be enough */
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strerror_s(allocated, 4096, num);
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vec_push(vector, allocated);
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return (const char *)allocated;
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}
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int util_snprintf(char *src, size_t bytes, const char *format, ...) {
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int rt;
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va_list va;
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va_start(va, format);
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rt = vsprintf_s(src, bytes, format, va);
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va_end (va);
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return rt;
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}
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char *util_strcat(char *dest, const char *src) {
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strcat_s(dest, strlen(src), src);
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return dest;
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}
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char *util_strncpy(char *dest, const char *src, size_t num) {
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strncpy_s(dest, num, src, num);
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return dest;
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}
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#else
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const char *util_strerror(int num) {
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return strerror(num);
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}
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int util_snprintf(char *src, size_t bytes, const char *format, ...) {
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int rt;
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va_list va;
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va_start(va, format);
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rt = vsnprintf(src, bytes, format, va);
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va_end (va);
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return rt;
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}
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char *util_strcat(char *dest, const char *src) {
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return strcat(dest, src);
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}
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char *util_strncpy(char *dest, const char *src, size_t num) {
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return strncpy(dest, src, num);
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}
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#endif /*! _MSC_VER */
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/*
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* Implementation of the Mersenne twister PRNG (pseudo random numer
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* generator). Implementation of MT19937. Has a period of 2^19937-1
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* which is a Mersenne Prime (hence the name).
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*
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* Implemented from specification and original paper:
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* http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/ARTICLES/mt.pdf
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*
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* This code is placed in the public domain by me personally
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* (Dale Weiler, a.k.a graphitemaster).
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*/
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#define MT_SIZE 624
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#define MT_PERIOD 397
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#define MT_SPACE (MT_SIZE - MT_PERIOD)
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static uint32_t mt_state[MT_SIZE];
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static size_t mt_index = 0;
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static GMQCC_INLINE void mt_generate(void) {
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/*
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* The loop has been unrolled here: the original paper and implemenation
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* Called for the following code:
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* for (register unsigned i = 0; i < MT_SIZE; ++i) {
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* register uint32_t load;
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* load = (0x80000000 & mt_state[i]) // most significant 32nd bit
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* load |= (0x7FFFFFFF & mt_state[(i + 1) % MT_SIZE]) // least significant 31nd bit
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*
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* mt_state[i] = mt_state[(i + MT_PERIOD) % MT_SIZE] ^ (load >> 1);
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*
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* if (load & 1) mt_state[i] ^= 0x9908B0DF;
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* }
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*
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* This essentially is a waste: we have two modulus operations, and
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* a branch that is executed every iteration from [0, MT_SIZE).
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*
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* Please see: http://www.quadibloc.com/crypto/co4814.htm for more
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* information on how this clever trick works.
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*/
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static const uint32_t matrix[2] = {
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0x00000000,
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0x9908B0Df
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};
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/*
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* This register gives up a little more speed by instructing the compiler
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* to force these into CPU registers (they're counters for indexing mt_state
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* which we can force the compiler to generate prefetch instructions for)
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*/
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register uint32_t y;
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register uint32_t i;
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/*
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* Said loop has been unrolled for MT_SPACE (226 iterations), opposed
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* to [0, MT_SIZE) (634 iterations).
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*/
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for (i = 0; i < MT_SPACE-1; ++i) {
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y = (0x80000000 & mt_state[i]) | (0x7FFFFFF & mt_state[i + 1]);
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mt_state[i] = mt_state[i + MT_PERIOD] ^ (y >> 1) ^ matrix[y & 1];
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i ++; /* loop unroll */
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y = (0x80000000 & mt_state[i]) | (0x7FFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i + MT_PERIOD] ^ (y >> 1) ^ matrix[y & 1];
|
|
}
|
|
|
|
/*
|
|
* collapsing the walls unrolled (evenly dividing 396 [632-227 = 396
|
|
* = 2*2*3*3*11])
|
|
*/
|
|
i = MT_SPACE;
|
|
while (i < MT_SIZE-2) {
|
|
/*
|
|
* We expand this 11 times .. manually, no macros are required
|
|
* here. This all fits in the CPU cache.
|
|
*/
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
|
|
mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
|
|
++i;
|
|
}
|
|
|
|
/* i = mt_state[623] */
|
|
y = (0x80000000 & mt_state[MT_SIZE - 1]) | (0x7FFFFFFF & mt_state[MT_SIZE - 1]);
|
|
mt_state[MT_SIZE - 1] = mt_state[MT_PERIOD - 1] ^ (y >> 1) ^ matrix[y & 1];
|
|
}
|
|
|
|
void util_seed(uint32_t value) {
|
|
/*
|
|
* We seed the mt_state with a LCG (linear congruential generator)
|
|
* We're operating exactly on exactly m=32, so there is no need to
|
|
* use modulus.
|
|
*
|
|
* The multipler of choice is 0x6C07865, also knows as the Borosh-
|
|
* Niederreiter multipler used for modulus 2^32. More can be read
|
|
* about this in Knuth's TAOCP Volume 2, page 106.
|
|
*
|
|
* If you don't own TAOCP something is wrong with you :-) .. so I
|
|
* also provided a link to the original paper by Borosh and
|
|
* Niederreiter. It's called "Optional Multipliers for PRNG by The
|
|
* Linear Congruential Method" (1983).
|
|
* http://en.wikipedia.org/wiki/Linear_congruential_generator
|
|
*
|
|
* From said page, it says the following:
|
|
* "A common Mersenne twister implementation, interestingly enough
|
|
* used an LCG to generate seed data."
|
|
*
|
|
* Remarks:
|
|
* The data we're operating on is 32-bits for the mt_state array, so
|
|
* there is no masking required with 0xFFFFFFFF
|
|
*/
|
|
register size_t i;
|
|
|
|
mt_state[0] = value;
|
|
for (i = 1; i < MT_SIZE; ++i)
|
|
mt_state[i] = 0x6C078965 * (mt_state[i - 1] ^ mt_state[i - 1] >> 30) + i;
|
|
}
|
|
|
|
uint32_t util_rand() {
|
|
register uint32_t y;
|
|
|
|
/*
|
|
* This is inlined with any sane compiler (I checked)
|
|
* for some reason though, SubC seems to be generating invalid
|
|
* code when it inlines this.
|
|
*/
|
|
if (!mt_index)
|
|
mt_generate();
|
|
|
|
y = mt_state[mt_index];
|
|
|
|
/* Standard tempering */
|
|
y ^= y >> 11; /* +7 */
|
|
y ^= y << 7 & 0x9D2C5680; /* +4 */
|
|
y ^= y << 15 & 0xEFC60000; /* -4 */
|
|
y ^= y >> 18; /* -7 */
|
|
|
|
if(++mt_index == MT_SIZE)
|
|
mt_index = 0;
|
|
|
|
return y;
|
|
}
|