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Comparing deliantra/server/include/util.h (file contents):
Revision 1.94 by root, Sun Nov 8 16:13:45 2009 UTC vs.
Revision 1.103 by root, Thu Apr 29 15:49:04 2010 UTC

1/* 1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG. 2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 * 3 *
4 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team 4 * Copyright (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 * 5 *
6 * Deliantra is free software: you can redistribute it and/or modify it under 6 * Deliantra is free software: you can redistribute it and/or modify it under
7 * the terms of the Affero GNU General Public License as published by the 7 * the terms of the Affero GNU General Public License as published by the
8 * Free Software Foundation, either version 3 of the License, or (at your 8 * Free Software Foundation, either version 3 of the License, or (at your
9 * option) any later version. 9 * option) any later version.
… …
55#endif 55#endif
56 56
57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) 57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
58#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
59 59
60// could use the sizeof (arr) /( sizeof (arr [0]) here, but C++ is
61// much more obfuscated... :)
62
63template<typename T, int N>
64inline int array_length (const T (&arr)[N])
65{
66 return N;
67}
68
60// very ugly macro that basically declares and initialises a variable 69// very ugly macro that basically declares and initialises a variable
61// that is in scope for the next statement only 70// that is in scope for the next statement only
62// works only for stuff that can be assigned 0 and converts to false 71// works only for stuff that can be assigned 0 and converts to false
63// (note: works great for pointers) 72// (note: works great for pointers)
64// most ugly macro I ever wrote 73// most ugly macro I ever wrote
… …
93// sign returns -1 or +1 102// sign returns -1 or +1
94template<typename T> 103template<typename T>
95static inline T sign (T v) { return v < 0 ? -1 : +1; } 104static inline T sign (T v) { return v < 0 ? -1 : +1; }
96// relies on 2c representation 105// relies on 2c representation
97template<> 106template<>
98inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } 107inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
108template<>
109inline sint16 sign (sint16 v) { return 1 - (sint16 (uint16 (v) >> 15) * 2); }
110template<>
111inline sint32 sign (sint32 v) { return 1 - (sint32 (uint32 (v) >> 31) * 2); }
99 112
100// sign0 returns -1, 0 or +1 113// sign0 returns -1, 0 or +1
101template<typename T> 114template<typename T>
102static inline T sign0 (T v) { return v ? sign (v) : 0; } 115static inline T sign0 (T v) { return v ? sign (v) : 0; }
116
117template<typename T, typename U>
118static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
103 119
104// div* only work correctly for div > 0 120// div* only work correctly for div > 0
105// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
106template<typename T> static inline T div (T val, T div) 122template<typename T> static inline T div (T val, T div)
107{ 123{
… …
240absdir (int d) 256absdir (int d)
241{ 257{
242 return ((d - 1) & 7) + 1; 258 return ((d - 1) & 7) + 1;
243} 259}
244 260
261// avoid ctz name because netbsd or freebsd spams it's namespace with it
262#if GCC_VERSION(3,4)
263static inline int least_significant_bit (uint32_t x)
264{
265 return __builtin_ctz (x);
266}
267#else
268int least_significant_bit (uint32_t x);
269#endif
270
271#define for_all_bits_sparse_32(mask, idxvar) \
272 for (uint32_t idxvar, mask_ = mask; \
273 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
274
245extern ssize_t slice_alloc; // statistics 275extern ssize_t slice_alloc; // statistics
246 276
247void *salloc_ (int n) throw (std::bad_alloc); 277void *salloc_ (int n) throw (std::bad_alloc);
248void *salloc_ (int n, void *src) throw (std::bad_alloc); 278void *salloc_ (int n, void *src) throw (std::bad_alloc);
249 279
… …
453 return !is_constant (num) ? get_range (num) // non-constant 483 return !is_constant (num) ? get_range (num) // non-constant
454 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 484 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
455 : this->next () & (num - 1); // constant, power-of-two 485 : this->next () & (num - 1); // constant, power-of-two
456 } 486 }
457 487
458 // return a number within (min .. max) 488 // return a number within the closed interval [min .. max]
459 int operator () (int r_min, int r_max) 489 int operator () (int r_min, int r_max)
460 { 490 {
461 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 491 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
462 ? r_min + operator ()(r_max - r_min + 1) 492 ? r_min + operator ()(r_max - r_min + 1)
463 : get_range (r_min, r_max); 493 : get_range (r_min, r_max);
464 } 494 }
465 495
496 // return a number within the closed interval [0..1]
466 double operator ()() 497 double operator ()()
467 { 498 {
468 return this->next () / (double)0xFFFFFFFFU; 499 return this->next () / (double)0xFFFFFFFFU;
469 } 500 }
470 501
… …
545typedef refptr<maptile> maptile_ptr; 576typedef refptr<maptile> maptile_ptr;
546typedef refptr<object> object_ptr; 577typedef refptr<object> object_ptr;
547typedef refptr<archetype> arch_ptr; 578typedef refptr<archetype> arch_ptr;
548typedef refptr<client> client_ptr; 579typedef refptr<client> client_ptr;
549typedef refptr<player> player_ptr; 580typedef refptr<player> player_ptr;
581typedef refptr<region> region_ptr;
582
583#define STRHSH_NULL 2166136261
584
585static inline uint32_t
586strhsh (const char *s)
587{
588 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
589 // it is about twice as fast as the one-at-a-time one,
590 // with good distribution.
591 // FNV-1a is faster on many cpus because the multiplication
592 // runs concurrently with the looping logic.
593 uint32_t hash = STRHSH_NULL;
594
595 while (*s)
596 hash = (hash ^ *s++) * 16777619U;
597
598 return hash;
599}
600
601static inline uint32_t
602memhsh (const char *s, size_t len)
603{
604 uint32_t hash = STRHSH_NULL;
605
606 while (len--)
607 hash = (hash ^ *s++) * 16777619U;
608
609 return hash;
610}
550 611
551struct str_hash 612struct str_hash
552{ 613{
553 std::size_t operator ()(const char *s) const 614 std::size_t operator ()(const char *s) const
554 { 615 {
555#if 0
556 uint32_t hash = 0;
557
558 /* use the one-at-a-time hash function, which supposedly is
559 * better than the djb2-like one used by perl5.005, but
560 * certainly is better then the bug used here before.
561 * see http://burtleburtle.net/bob/hash/doobs.html
562 */
563 while (*s)
564 {
565 hash += *s++;
566 hash += hash << 10;
567 hash ^= hash >> 6;
568 }
569
570 hash += hash << 3;
571 hash ^= hash >> 11;
572 hash += hash << 15;
573#else
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
575 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrent with the looping logic.
579 uint32_t hash = 2166136261;
580
581 while (*s)
582 hash = (hash ^ *s++) * 16777619;
583#endif
584
585 return hash; 616 return strhsh (s);
617 }
618
619 std::size_t operator ()(const shstr &s) const
620 {
621 return strhsh (s);
586 } 622 }
587}; 623};
588 624
589struct str_equal 625struct str_equal
590{ 626{

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