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Comparing deliantra/server/include/util.h (file contents):
Revision 1.95 by root, Tue Nov 10 00:01:31 2009 UTC vs.
Revision 1.113 by root, Fri Apr 22 02:03:11 2011 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#if cplusplus_does_not_suck
61// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
62template<typename T, int N>
63static inline int array_length (const T (&arr)[N])
64{
65 return N;
66}
67#else
68#define array_length(name) (sizeof (name) / sizeof (name [0]))
69#endif
70
60// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
61// that is in scope for the next statement only 72// that is in scope for the next statement only
62// works only for stuff that can be assigned 0 and converts to false 73// works only for stuff that can be assigned 0 and converts to false
63// (note: works great for pointers) 74// (note: works great for pointers)
64// most ugly macro I ever wrote 75// most ugly macro I ever wrote
… …
93// sign returns -1 or +1 104// sign returns -1 or +1
94template<typename T> 105template<typename T>
95static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
96// relies on 2c representation 107// relies on 2c representation
97template<> 108template<>
98inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } 109inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
110template<>
111inline sint16 sign (sint16 v) { return 1 - (sint16 (uint16 (v) >> 15) * 2); }
112template<>
113inline sint32 sign (sint32 v) { return 1 - (sint32 (uint32 (v) >> 31) * 2); }
99 114
100// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
101template<typename T> 116template<typename T>
102static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
118
119//clashes with C++0x
120template<typename T, typename U>
121static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
103 122
104// div* only work correctly for div > 0 123// div* only work correctly for div > 0
105// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 124// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
106template<typename T> static inline T div (T val, T div) 125template<typename T> static inline T div (T val, T div)
107{ 126{
108 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 127 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
109} 128}
129
130template<> inline float div (float val, float div) { return val / div; }
131template<> inline double div (double val, double div) { return val / div; }
132
110// div, round-up 133// div, round-up
111template<typename T> static inline T div_ru (T val, T div) 134template<typename T> static inline T div_ru (T val, T div)
112{ 135{
113 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 136 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
114} 137}
… …
240absdir (int d) 263absdir (int d)
241{ 264{
242 return ((d - 1) & 7) + 1; 265 return ((d - 1) & 7) + 1;
243} 266}
244 267
268// avoid ctz name because netbsd or freebsd spams it's namespace with it
269#if GCC_VERSION(3,4)
270static inline int least_significant_bit (uint32_t x)
271{
272 return __builtin_ctz (x);
273}
274#else
275int least_significant_bit (uint32_t x);
276#endif
277
278#define for_all_bits_sparse_32(mask, idxvar) \
279 for (uint32_t idxvar, mask_ = mask; \
280 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
281
245extern ssize_t slice_alloc; // statistics 282extern ssize_t slice_alloc; // statistics
246 283
247void *salloc_ (int n) throw (std::bad_alloc); 284void *salloc_ (int n) throw (std::bad_alloc);
248void *salloc_ (int n, void *src) throw (std::bad_alloc); 285void *salloc_ (int n, void *src) throw (std::bad_alloc);
249 286
… …
393 { 430 {
394 p->~Tp (); 431 p->~Tp ();
395 } 432 }
396}; 433};
397 434
398// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
399// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
400// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
401struct tausworthe_random_generator
402{
403 uint32_t state [4];
404
405 void operator =(const tausworthe_random_generator &src)
406 {
407 state [0] = src.state [0];
408 state [1] = src.state [1];
409 state [2] = src.state [2];
410 state [3] = src.state [3];
411 }
412
413 void seed (uint32_t seed);
414 uint32_t next ();
415};
416
417// Xorshift RNGs, George Marsaglia
418// http://www.jstatsoft.org/v08/i14/paper
419// this one is about 40% faster than the tausworthe one above (i.e. not much),
420// despite the inlining, and has the issue of only creating 2**32-1 numbers.
421// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
422struct xorshift_random_generator
423{
424 uint32_t x, y;
425
426 void operator =(const xorshift_random_generator &src)
427 {
428 x = src.x;
429 y = src.y;
430 }
431
432 void seed (uint32_t seed)
433 {
434 x = seed;
435 y = seed * 69069U;
436 }
437
438 uint32_t next ()
439 {
440 uint32_t t = x ^ (x << 10);
441 x = y;
442 y = y ^ (y >> 13) ^ t ^ (t >> 10);
443 return y;
444 }
445};
446
447template<class generator>
448struct random_number_generator : generator
449{
450 // uniform distribution, 0 .. max (0, num - 1)
451 uint32_t operator ()(uint32_t num)
452 {
453 return !is_constant (num) ? get_range (num) // non-constant
454 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
455 : this->next () & (num - 1); // constant, power-of-two
456 }
457
458 // return a number within (min .. max)
459 int operator () (int r_min, int r_max)
460 {
461 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
462 ? r_min + operator ()(r_max - r_min + 1)
463 : get_range (r_min, r_max);
464 }
465
466 double operator ()()
467 {
468 return this->next () / (double)0xFFFFFFFFU;
469 }
470
471protected:
472 uint32_t get_range (uint32_t r_max);
473 int get_range (int r_min, int r_max);
474};
475
476typedef random_number_generator<tausworthe_random_generator> rand_gen;
477
478extern rand_gen rndm, rmg_rndm;
479
480INTERFACE_CLASS (attachable) 435INTERFACE_CLASS (attachable)
481struct refcnt_base 436struct refcnt_base
482{ 437{
483 typedef int refcnt_t; 438 typedef int refcnt_t;
484 mutable refcnt_t ACC (RW, refcnt); 439 mutable refcnt_t ACC (RW, refcnt);
… …
545typedef refptr<maptile> maptile_ptr; 500typedef refptr<maptile> maptile_ptr;
546typedef refptr<object> object_ptr; 501typedef refptr<object> object_ptr;
547typedef refptr<archetype> arch_ptr; 502typedef refptr<archetype> arch_ptr;
548typedef refptr<client> client_ptr; 503typedef refptr<client> client_ptr;
549typedef refptr<player> player_ptr; 504typedef refptr<player> player_ptr;
505typedef refptr<region> region_ptr;
550 506
551#define STRHSH_NULL 2166136261 507#define STRHSH_NULL 2166136261
552 508
553static inline uint32_t 509static inline uint32_t
554strhsh (const char *s) 510strhsh (const char *s)
… …
556 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) 512 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
557 // it is about twice as fast as the one-at-a-time one, 513 // it is about twice as fast as the one-at-a-time one,
558 // with good distribution. 514 // with good distribution.
559 // FNV-1a is faster on many cpus because the multiplication 515 // FNV-1a is faster on many cpus because the multiplication
560 // runs concurrently with the looping logic. 516 // runs concurrently with the looping logic.
517 // we modify the hash a bit to improve its distribution
561 uint32_t hash = STRHSH_NULL; 518 uint32_t hash = STRHSH_NULL;
562 519
563 while (*s) 520 while (*s)
564 hash = (hash ^ *s++) * 16777619; 521 hash = (hash ^ *s++) * 16777619U;
565 522
566 return hash; 523 return hash ^ (hash >> 16);
567} 524}
568 525
569static inline uint32_t 526static inline uint32_t
570memhsh (const char *s, size_t len) 527memhsh (const char *s, size_t len)
571{ 528{
572 uint32_t hash = STRHSH_NULL; 529 uint32_t hash = STRHSH_NULL;
573 530
574 while (len--) 531 while (len--)
575 hash = (hash ^ *s++) * 16777619; 532 hash = (hash ^ *s++) * 16777619U;
576 533
577 return hash; 534 return hash;
578} 535}
579 536
580struct str_hash 537struct str_hash
… …
686 { 643 {
687 erase (&obj); 644 erase (&obj);
688 } 645 }
689}; 646};
690 647
648/////////////////////////////////////////////////////////////////////////////
649
650// something like a vector or stack, but without
651// out of bounds checking
652template<typename T>
653struct fixed_stack
654{
655 T *data;
656 int size;
657 int max;
658
659 fixed_stack ()
660 : size (0), data (0)
661 {
662 }
663
664 fixed_stack (int max)
665 : size (0), max (max)
666 {
667 data = salloc<T> (max);
668 }
669
670 void reset (int new_max)
671 {
672 sfree (data, max);
673 size = 0;
674 max = new_max;
675 data = salloc<T> (max);
676 }
677
678 void free ()
679 {
680 sfree (data, max);
681 data = 0;
682 }
683
684 ~fixed_stack ()
685 {
686 sfree (data, max);
687 }
688
689 T &operator[](int idx)
690 {
691 return data [idx];
692 }
693
694 void push (T v)
695 {
696 data [size++] = v;
697 }
698
699 T &pop ()
700 {
701 return data [--size];
702 }
703
704 T remove (int idx)
705 {
706 T v = data [idx];
707
708 data [idx] = data [--size];
709
710 return v;
711 }
712};
713
714/////////////////////////////////////////////////////////////////////////////
715
691// basically does what strncpy should do, but appends "..." to strings exceeding length 716// basically does what strncpy should do, but appends "..." to strings exceeding length
692// returns the number of bytes actually used (including \0) 717// returns the number of bytes actually used (including \0)
693int assign (char *dst, const char *src, int maxsize); 718int assign (char *dst, const char *src, int maxsize);
694 719
695// type-safe version of assign 720// type-safe version of assign

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