2 * Copyright (C) 2012, 2013
6 * Permission is hereby granted, free of charge, to any person obtaining a copy of
7 * this software and associated documentation files (the "Software"), to deal in
8 * the Software without restriction, including without limitation the rights to
9 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
10 * of the Software, and to permit persons to whom the Software is furnished to do
11 * so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in all
14 * copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
28 /* TODO: remove globals ... */
38 struct memblock_t *next;
39 struct memblock_t *prev;
42 static struct memblock_t *mem_start = NULL;
44 void *util_memory_a(size_t byte, unsigned int line, const char *file) {
45 struct memblock_t *info = (struct memblock_t*)malloc(sizeof(struct memblock_t) + byte);
46 void *data = (void*)(info+1);
47 if (!info) return NULL;
52 info->next = mem_start;
54 mem_start->prev = info;
63 void util_memory_d(void *ptrn) {
64 struct memblock_t *info = NULL;
67 info = ((struct memblock_t*)ptrn - 1);
73 info->prev->next = info->next;
75 info->next->prev = info->prev;
76 if (info == mem_start)
77 mem_start = info->next;
82 void *util_memory_r(void *ptrn, size_t byte, unsigned int line, const char *file) {
83 struct memblock_t *oldinfo = NULL;
85 struct memblock_t *newinfo;
88 return util_memory_a(byte, line, file);
94 oldinfo = ((struct memblock_t*)ptrn - 1);
95 newinfo = ((struct memblock_t*)malloc(sizeof(struct memblock_t) + byte));
99 util_memory_d(oldinfo+1);
104 memcpy(newinfo+1, oldinfo+1, oldinfo->byte);
108 oldinfo->prev->next = oldinfo->next;
110 oldinfo->next->prev = oldinfo->prev;
111 if (oldinfo == mem_start)
112 mem_start = oldinfo->next;
115 newinfo->line = line;
116 newinfo->byte = byte;
117 newinfo->file = file;
118 newinfo->prev = NULL;
119 newinfo->next = mem_start;
121 mem_start->prev = newinfo;
124 mem_ab -= oldinfo->byte;
125 mem_ab += newinfo->byte;
132 void util_meminfo() {
133 struct memblock_t *info;
135 if (!OPTS_OPTION_BOOL(OPTION_MEMCHK))
138 for (info = mem_start; info; info = info->next) {
139 con_out("lost: % 8u (bytes) at %s:%u\n",
145 con_out("Memory information:\n\
146 Total allocations: %llu\n\
147 Total deallocations: %llu\n\
148 Total allocated: %llu (bytes)\n\
149 Total deallocated: %llu (bytes)\n\
150 Leaks found: lost %llu (bytes) in %d allocations\n",
159 * Some string utility functions, because strdup uses malloc, and we want
160 * to track all memory (without replacing malloc).
162 char *_util_Estrdup(const char *s, const char *file, size_t line) {
166 /* in case of -DNOTRACK */
173 if ((len = strlen(s)) && (ptr = (char*)mem_af(len+1, line, file))) {
180 void util_debug(const char *area, const char *ms, ...) {
182 if (!OPTS_OPTION_BOOL(OPTION_DEBUG))
185 if (!strcmp(area, "MEM") && !OPTS_OPTION_BOOL(OPTION_MEMCHK))
189 con_out ("[%s] ", area);
195 * only required if big endian .. otherwise no need to swap
198 #if PLATFORM_BYTE_ORDER == GMQCC_BYTE_ORDER_BIG
199 static GMQCC_INLINE void util_swap16(uint16_t *d, size_t l) {
201 d[l] = (d[l] << 8) | (d[l] >> 8);
205 static GMQCC_INLINE void util_swap32(uint32_t *d, size_t l) {
208 v = ((d[l] << 8) & 0xFF00FF00) | ((d[l] >> 8) & 0x00FF00FF);
209 d[l] = (v << 16) | (v >> 16);
213 /* Some strange system doesn't like constants that big, AND doesn't recognize an ULL suffix
214 * so let's go the safe way
216 static GMQCC_INLINE void util_swap64(uint32_t *d, size_t l) {
220 v = ((d[l] << 8) & 0xFF00FF00FF00FF00) | ((d[l] >> 8) & 0x00FF00FF00FF00FF);
221 v = ((v << 16) & 0xFFFF0000FFFF0000) | ((v >> 16) & 0x0000FFFF0000FFFF);
222 d[l] = (v << 32) | (v >> 32);
226 for (i = 0; i < l; i += 2) {
235 void util_endianswap(void *_data, size_t length, unsigned int typesize) {
236 # if PLATFORM_BYTE_ORDER == -1 /* runtime check */
237 if (*((char*)&typesize))
240 /* prevent unused warnings */
245 # if PLATFORM_BYTE_ORDER == GMQCC_BYTE_ORDER_LITTLE
251 util_swap16((uint16_t*)_data, length>>1);
254 util_swap32((uint32_t*)_data, length>>2);
257 util_swap64((uint32_t*)_data, length>>3);
260 default: exit(EXIT_FAILURE); /* please blow the fuck up! */
267 * CRC algorithms vary in the width of the polynomial, the value of said polynomial,
268 * the initial value used for the register, weather the bits of each byte are reflected
269 * before being processed, weather the algorithm itself feeds input bytes through the
270 * register or XORs them with a byte from one end and then straight into the table, as
271 * well as (but not limited to the idea of reflected versions) where the final register
272 * value becomes reversed, and finally weather the value itself is used to XOR the final
273 * register value. AS such you can already imagine how painfully annoying CRCs are,
274 * of course we stand to target Quake, which expects it's certian set of rules for proper
275 * calculation of a CRC.
277 * In most traditional CRC algorithms on uses a reflected table driven method where a value
278 * or register is reflected if it's bits are swapped around it's center. For example:
279 * take the bits 0101 is the 4-bit reflection of 1010, and respectfully 0011 would be the
280 * reflection of 1100. Quake however expects a NON-Reflected CRC on the output, but still
281 * requires a final XOR on the values (0xFFFF and 0x0000) this is a standard CCITT CRC-16
282 * which I respectfully as a programmer don't agree with.
284 * So now you know what we target, and why we target it, despite how unsettling it may seem
285 * but those are what Quake seems to request.
288 static const uint16_t util_crc16_table[] = {
289 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5,
290 0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B,
291 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210,
292 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
293 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C,
294 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401,
295 0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B,
296 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
297 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6,
298 0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738,
299 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5,
300 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
301 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969,
302 0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96,
303 0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC,
304 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
305 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03,
306 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD,
307 0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6,
308 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
309 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A,
310 0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB,
311 0xD10C, 0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1,
312 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
313 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C,
314 0xE37F, 0xF35E, 0x02B1, 0x1290, 0x22F3, 0x32D2,
315 0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB,
316 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
317 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447,
318 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8,
319 0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2,
320 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
321 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9,
322 0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827,
323 0x18C0, 0x08E1, 0x3882, 0x28A3, 0xCB7D, 0xDB5C,
324 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
325 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0,
326 0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D,
327 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07,
328 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
329 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA,
330 0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74,
331 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
334 /* Non - Reflected */
335 uint16_t util_crc16(uint16_t current, const char *k, size_t len) {
336 register uint16_t h = current;
337 for (; len; --len, ++k)
338 h = util_crc16_table[(h>>8)^((unsigned char)*k)]^(h<<8);
341 /* Reflective Varation (for reference) */
343 uint16_t util_crc16(const char *k, int len, const short clamp) {
344 register uint16_t h= (uint16_t)0xFFFFFFFF;
345 for (; len; --len, ++k)
346 h = util_crc16_table[(h^((unsigned char)*k))&0xFF]^(h>>8);
351 size_t util_strtocmd(const char *in, char *out, size_t outsz) {
353 for (; *in && sz < outsz; ++in, ++out, ++sz)
354 *out = (*in == '-') ? '_' : (isalpha(*in) && !isupper(*in)) ? *in + 'A' - 'a': *in;
359 size_t util_strtononcmd(const char *in, char *out, size_t outsz) {
361 for (; *in && sz < outsz; ++in, ++out, ++sz)
362 *out = (*in == '_') ? '-' : (isalpha(*in) && isupper(*in)) ? *in + 'a' - 'A' : *in;
367 /* TODO: rewrite ... when I redo the ve cleanup */
368 void _util_vec_grow(void **a, size_t i, size_t s) {
369 vector_t *d = vec_meta(*a);
370 size_t m = *a ? 2 * d->allocated +i : i+1;
371 void *p = mem_r((*a ? d : NULL), s * m + sizeof(vector_t));
374 ((vector_t*)p)->used = 0;
375 *a = (vector_t*)p + 1;
377 vec_meta(*a)->allocated = m;
381 * Hash table for generic data, based on dynamic memory allocations
382 * all around. This is the internal interface, please look for
383 * EXPOSED INTERFACE comment below
385 typedef struct hash_node_t {
386 char *key; /* the key for this node in table */
387 void *value; /* pointer to the data as void* */
388 struct hash_node_t *next; /* next node (linked list) */
391 GMQCC_INLINE size_t util_hthash(hash_table_t *ht, const char *key) {
392 const uint32_t mix = 0x5BD1E995;
393 const uint32_t rot = 24;
394 size_t size = strlen(key);
395 uint32_t hash = 0x1EF0 /* LICRC TAB */ ^ size;
397 const unsigned char *data = (const unsigned char*)key;
400 alias = *(uint32_t*)data;
403 alias ^= alias >> rot;
414 case 3: hash ^= data[2] << 16;
415 case 2: hash ^= data[1] << 8;
416 case 1: hash ^= data[0];
424 return (size_t) (hash % ht->size);
427 hash_node_t *_util_htnewpair(const char *key, void *value) {
429 if (!(node = (hash_node_t*)mem_a(sizeof(hash_node_t))))
432 if (!(node->key = util_strdup(key))) {
444 * EXPOSED INTERFACE for the hashtable implementation
445 * util_htnew(size) -- to make a new hashtable
446 * util_htset(table, key, value, sizeof(value)) -- to set something in the table
447 * util_htget(table, key) -- to get something from the table
448 * util_htdel(table) -- to delete the table
450 hash_table_t *util_htnew(size_t size) {
451 hash_table_t *hashtable = NULL;
455 if (!(hashtable = (hash_table_t*)mem_a(sizeof(hash_table_t))))
458 if (!(hashtable->table = (hash_node_t**)mem_a(sizeof(hash_node_t*) * size))) {
463 hashtable->size = size;
464 memset(hashtable->table, 0, sizeof(hash_node_t*) * size);
469 void util_htseth(hash_table_t *ht, const char *key, size_t bin, void *value) {
470 hash_node_t *newnode = NULL;
471 hash_node_t *next = NULL;
472 hash_node_t *last = NULL;
474 next = ht->table[bin];
476 while (next && next->key && strcmp(key, next->key) > 0)
477 last = next, next = next->next;
479 /* already in table, do a replace */
480 if (next && next->key && strcmp(key, next->key) == 0) {
483 /* not found, grow a pair man :P */
484 newnode = _util_htnewpair(key, value);
485 if (next == ht->table[bin]) {
486 newnode->next = next;
487 ht->table[bin] = newnode;
489 last->next = newnode;
491 newnode->next = next;
492 last->next = newnode;
497 void util_htset(hash_table_t *ht, const char *key, void *value) {
498 util_htseth(ht, key, util_hthash(ht, key), value);
501 void *util_htgeth(hash_table_t *ht, const char *key, size_t bin) {
502 hash_node_t *pair = ht->table[bin];
504 while (pair && pair->key && strcmp(key, pair->key) > 0)
507 if (!pair || !pair->key || strcmp(key, pair->key) != 0)
513 void *util_htget(hash_table_t *ht, const char *key) {
514 return util_htgeth(ht, key, util_hthash(ht, key));
517 void *code_util_str_htgeth(hash_table_t *ht, const char *key, size_t bin) {
522 keylen = strlen(key);
524 pair = ht->table[bin];
525 while (pair && pair->key) {
526 len = strlen(pair->key);
532 cmp = strcmp(key, pair->key);
540 cmp = strcmp(key, pair->key + len - keylen);
542 uintptr_t up = (uintptr_t)pair->value;
552 * Free all allocated data in a hashtable, this is quite the amount
555 void util_htdel(hash_table_t *ht) {
557 for (; i < ht->size; i++) {
558 hash_node_t *n = ht->table[i];
577 * A basic implementation of a hash-set. Unlike a hashtable, a hash
578 * set doesn't maintain key-value pairs. It simply maintains a key
579 * that can be set, removed, and checked for.
581 * See EXPOSED interface comment below
583 #define GMQCC_HASHSET_PRIME0 0x0049
584 #define GMQCC_HASHSET_PRIME1 0x1391
586 static int util_hsput(hash_set_t *set, void *item) {
587 size_t hash = (size_t)item; /* shouldn't drop the bits */
590 /* a == 0 || a == 1 */
594 iter = set->mask & (GMQCC_HASHSET_PRIME0 * hash);
596 /* while (set->items[iter] != 0 && set->items[iter] != 1) */
597 while (!(set->items[iter] >> 1)) {
598 if (set->items[iter] == hash)
601 iter = set->mask & (iter + GMQCC_HASHSET_PRIME1);
605 set->items[iter] = hash;
610 static void util_hsupdate(hash_set_t *set) {
615 /* time to rehash? */
616 if ((float)set->total >= (size_t)((double)set->capacity * 0.85)) {
621 set->capacity = (size_t)(1 << set->bits);
622 set->mask = set->capacity - 1;
623 set->items = (size_t*)mem_a(set->capacity * sizeof(size_t));
626 /*assert(set->items);*/
629 * this shouldn't be slow? if so unroll it a little perhaps
630 * (shouldn't be though)
632 for (itr = 0; itr < end; itr++)
633 util_hsput(set, (void*)old[itr]);
640 * EXPOSED interface: all of these functions are exposed to the outside
641 * for use. The stuff above is static because it's the "internal" mechanics
642 * for syncronizing the set for updating, and putting data into the set.
644 int util_hsadd(hash_set_t *set, void *item) {
645 int run = util_hsput(set, item); /* inlined */
651 /* remove item in set */
652 int util_hsrem(hash_set_t *set, void *item) {
653 size_t hash = (size_t)item;
654 size_t iter = set->mask & (GMQCC_HASHSET_PRIME0 * hash);
656 while (set->items[iter]) {
657 if (set->items[iter] == hash) {
658 set->items[iter] = 1;
663 iter = set->mask & (iter + GMQCC_HASHSET_PRIME1);
669 /* check if item is set */
670 int util_hshas(hash_set_t *set, void *item) {
671 size_t hash = (size_t)item;
672 size_t iter = set->mask & (GMQCC_HASHSET_PRIME0 * hash);
674 while (set->items[iter]) {
675 if (set->items[iter] == hash)
678 iter = set->mask & (iter + GMQCC_HASHSET_PRIME1);
684 hash_set_t *util_hsnew(void) {
687 if (!(set = (hash_set_t*)mem_a(sizeof(hash_set_t))))
692 set->capacity = (size_t)(1 << set->bits);
693 set->mask = set->capacity - 1;
694 set->items = (size_t*)mem_a(set->capacity * sizeof(size_t));
704 void util_hsdel(hash_set_t *set) {
712 #undef GMQCC_HASHSET_PRIME0
713 #undef GMQCC_HASHSET_PRIME1
717 * Portable implementation of vasprintf/asprintf. Assumes vsnprintf
718 * exists, otherwise compiler error.
720 * TODO: fix for MSVC ....
722 int util_vasprintf(char **dat, const char *fmt, va_list args) {
728 * For visuals tido _vsnprintf doesn't tell you the length of a
729 * formatted string if it overflows. However there is a MSVC
730 * intrinsic (which is documented wrong) called _vcsprintf which
731 * will return the required amount to allocate.
735 if ((len = _vscprintf(fmt, args)) < 0) {
740 tmp = mem_a(len + 1);
741 if ((ret = _vsnprintf(tmp, len+1, fmt, args)) != len) {
750 * For everything else we have a decent conformint vsnprintf that
751 * returns the number of bytes needed. We give it a try though on
752 * a short buffer, since efficently speaking, it could be nice to
753 * above a second vsnprintf call.
758 len = vsnprintf(buf, sizeof(buf), fmt, cpy);
761 if (len < (int)sizeof(buf)) {
762 *dat = util_strdup(buf);
766 /* not large enough ... */
767 tmp = (char*)mem_a(len + 1);
768 if ((ret = vsnprintf(tmp, len + 1, fmt, args)) != len) {
778 int util_asprintf(char **ret, const char *fmt, ...) {
782 read = util_vasprintf(ret, fmt, args);
789 * Implementation of the Mersenne twister PRNG (pseudo random numer
790 * generator). Implementation of MT19937. Has a period of 2^19937-1
791 * which is a Mersenne Prime (hence the name).
793 * Implemented from specification and original paper:
794 * http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/ARTICLES/mt.pdf
796 * This code is placed in the public domain by me personally
797 * (Dale Weiler, a.k.a graphitemaster).
801 #define MT_PERIOD 397
802 #define MT_SPACE (MT_SIZE - MT_PERIOD)
804 static uint32_t mt_state[MT_SIZE];
805 static size_t mt_index = 0;
807 static GMQCC_INLINE void mt_generate() {
809 * The loop has been unrolled here: the original paper and implemenation
810 * Called for the following code:
811 * for (register unsigned i = 0; i < MT_SIZE; ++i) {
812 * register uint32_t load;
813 * load = (0x80000000 & mt_state[i]) // most significant 32nd bit
814 * load |= (0x7FFFFFFF & mt_state[(i + 1) % MT_SIZE]) // least significant 31nd bit
816 * mt_state[i] = mt_state[(i + MT_PERIOD) % MT_SIZE] ^ (load >> 1);
818 * if (load & 1) mt_state[i] ^= 0x9908B0DF;
821 * This essentially is a waste: we have two modulus operations, and
822 * a branch that is executed every iteration from [0, MT_SIZE).
824 * Please see: http://www.quadibloc.com/crypto/co4814.htm for more
825 * information on how this clever trick works.
827 static const uint32_t matrix[2] = {
832 * This register gives up a little more speed by instructing the compiler
833 * to force these into CPU registers (they're counters for indexing mt_state
834 * which we can force the compiler to generate prefetch instructions for)
840 * Said loop has been unrolled for MT_SPACE (226 iterations), opposed
841 * to [0, MT_SIZE) (634 iterations).
843 for (i = 0; i < MT_SPACE; ++i) {
844 y = (0x80000000 & mt_state[i]) | (0x7FFFFFF & mt_state[i + 1]);
845 mt_state[i] = mt_state[i + MT_PERIOD] ^ (y >> 1) ^ matrix[y & 1];
847 i ++; /* loop unroll */
849 y = (0x80000000 & mt_state[i]) | (0x7FFFFFF & mt_state[i + 1]);
850 mt_state[i] = mt_state[i + MT_PERIOD] ^ (y >> 1) ^ matrix[y & 1];
854 * collapsing the walls unrolled (evenly dividing 396 [632-227 = 396
858 while (i < MT_SIZE - 1) {
860 * We expand this 11 times .. manually, no macros are required
861 * here. This all fits in the CPU cache.
863 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
864 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
866 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
867 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
869 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
870 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
872 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
873 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
875 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
876 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
878 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
879 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
881 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
882 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
884 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
885 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
887 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
888 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
890 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
891 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
893 y = (0x80000000 & mt_state[i]) | (0x7FFFFFFF & mt_state[i + 1]);
894 mt_state[i] = mt_state[i - MT_SPACE] ^ (y >> 1) ^ matrix[y & 1];
898 /* i = mt_state[623] */
899 y = (0x80000000 & mt_state[MT_SIZE - 1]) | (0x7FFFFFFF & mt_state[MT_SIZE - 1]);
900 mt_state[MT_SIZE - 1] = mt_state[MT_PERIOD - 1] ^ (y >> 1) ^ matrix[y & 1];
903 void util_seed(uint32_t value) {
905 * We seed the mt_state with a LCG (linear congruential generator)
906 * We're operating exactly on exactly m=32, so there is no need to
909 * The multipler of choice is 0x6C07865, also knows as the Borosh-
910 * Niederreiter multipler used for modulus 2^32. More can be read
911 * about this in Knuth's TAOCP Volume 2, page 106.
913 * If you don't own TAOCP something is wrong with you :-) .. so I
914 * also provided a link to the original paper by Borosh and
915 * Niederreiter. It's called "Optional Multipliers for PRNG by The
916 * Linear Congruential Method" (1983).
917 * http://en.wikipedia.org/wiki/Linear_congruential_generator
919 * From said page, it says the following:
920 * "A common Mersenne twister implementation, interestingly enough
921 * used an LCG to generate seed data."
924 * The data we're operating on is 32-bits for the mt_state array, so
925 * there is no masking required with 0xFFFFFFFF
930 for (i = 1; i < MT_SIZE; ++i)
931 mt_state[i] = 0x6C078965 * (mt_state[i - 1] ^ mt_state[i - 1] >> 30) + i;
934 uint32_t util_rand() {
938 * This is inlined with any sane compiler (I checked)
939 * for some reason though, SubC seems to be generating invalid
940 * code when it inlines this.
945 y = mt_state[mt_index];
947 /* Standard tempering */
948 y ^= y >> 11; /* +7 */
949 y ^= y << 7 & 0x9D2C5680; /* +4 */
950 y ^= y << 15 & 0xEFC60000; /* -4 */
951 y ^= y >> 18; /* -7 */
953 if(++mt_index == MT_SIZE)