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Comparing deliantra/server/include/util.h (file contents):
Revision 1.100 by root, Thu Apr 22 13:01:58 2010 UTC vs.
Revision 1.116 by root, Sat Dec 31 06:18:01 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 (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team 4 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011 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
… …
75void cleanup (const char *cause, bool make_core = false); 86void cleanup (const char *cause, bool make_core = false);
76void fork_abort (const char *msg); 87void fork_abort (const char *msg);
77 88
78// rationale for using (U) not (T) is to reduce signed/unsigned issues, 89// rationale for using (U) not (T) is to reduce signed/unsigned issues,
79// as a is often a constant while b is the variable. it is still a bug, though. 90// as a is often a constant while b is the variable. it is still a bug, though.
80template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; } 91template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
81template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; } 92template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
82template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; } 93template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }
83 94
84template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); } 95template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); }
85template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); } 96template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); }
86template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); } 97template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); }
… …
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; }
103 118
119//clashes with C++0x
104template<typename T, typename U> 120template<typename T, typename U>
105static inline T copysign (T a, U b) { return a > 0 ? b : -b; } 121static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
106 122
107// div* only work correctly for div > 0 123// div* only work correctly for div > 0
108// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 124// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
109template<typename T> static inline T div (T val, T div) 125template<typename T> static inline T div (T val, T div)
110{ 126{
111 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;
112} 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
113// div, round-up 133// div, round-up
114template<typename T> static inline T div_ru (T val, T div) 134template<typename T> static inline T div_ru (T val, T div)
115{ 135{
116 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 136 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
117} 137}
… …
232#else 252#else
233 return dx_ + dy_ - min (dx_, dy_) * 5 / 8; 253 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
234#endif 254#endif
235} 255}
236 256
257// can be substantially faster than floor, if your value range allows for it
258template<typename T>
259inline T
260fastfloor (T x)
261{
262 return std::floor (x);
263}
264
265inline float
266fastfloor (float x)
267{
268 return sint32(x) - (x < 0);
269}
270
271inline double
272fastfloor (double x)
273{
274 return sint64(x) - (x < 0);
275}
276
237/* 277/*
238 * absdir(int): Returns a number between 1 and 8, which represent 278 * absdir(int): Returns a number between 1 and 8, which represent
239 * the "absolute" direction of a number (it actually takes care of 279 * the "absolute" direction of a number (it actually takes care of
240 * "overflow" in previous calculations of a direction). 280 * "overflow" in previous calculations of a direction).
241 */ 281 */
… …
410 { 450 {
411 p->~Tp (); 451 p->~Tp ();
412 } 452 }
413}; 453};
414 454
415// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
416// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
417// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
418struct tausworthe_random_generator
419{
420 uint32_t state [4];
421
422 void operator =(const tausworthe_random_generator &src)
423 {
424 state [0] = src.state [0];
425 state [1] = src.state [1];
426 state [2] = src.state [2];
427 state [3] = src.state [3];
428 }
429
430 void seed (uint32_t seed);
431 uint32_t next ();
432};
433
434// Xorshift RNGs, George Marsaglia
435// http://www.jstatsoft.org/v08/i14/paper
436// this one is about 40% faster than the tausworthe one above (i.e. not much),
437// despite the inlining, and has the issue of only creating 2**32-1 numbers.
438// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
439struct xorshift_random_generator
440{
441 uint32_t x, y;
442
443 void operator =(const xorshift_random_generator &src)
444 {
445 x = src.x;
446 y = src.y;
447 }
448
449 void seed (uint32_t seed)
450 {
451 x = seed;
452 y = seed * 69069U;
453 }
454
455 uint32_t next ()
456 {
457 uint32_t t = x ^ (x << 10);
458 x = y;
459 y = y ^ (y >> 13) ^ t ^ (t >> 10);
460 return y;
461 }
462};
463
464template<class generator>
465struct random_number_generator : generator
466{
467 // uniform distribution, 0 .. max (0, num - 1)
468 uint32_t operator ()(uint32_t num)
469 {
470 return !is_constant (num) ? get_range (num) // non-constant
471 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
472 : this->next () & (num - 1); // constant, power-of-two
473 }
474
475 // return a number within the closed interval [min .. max]
476 int operator () (int r_min, int r_max)
477 {
478 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
479 ? r_min + operator ()(r_max - r_min + 1)
480 : get_range (r_min, r_max);
481 }
482
483 // return a number within the closed interval [0..1]
484 double operator ()()
485 {
486 return this->next () / (double)0xFFFFFFFFU;
487 }
488
489protected:
490 uint32_t get_range (uint32_t r_max);
491 int get_range (int r_min, int r_max);
492};
493
494typedef random_number_generator<tausworthe_random_generator> rand_gen;
495
496extern rand_gen rndm, rmg_rndm;
497
498INTERFACE_CLASS (attachable) 455INTERFACE_CLASS (attachable)
499struct refcnt_base 456struct refcnt_base
500{ 457{
501 typedef int refcnt_t; 458 typedef int refcnt_t;
502 mutable refcnt_t ACC (RW, refcnt); 459 mutable refcnt_t ACC (RW, refcnt);
… …
563typedef refptr<maptile> maptile_ptr; 520typedef refptr<maptile> maptile_ptr;
564typedef refptr<object> object_ptr; 521typedef refptr<object> object_ptr;
565typedef refptr<archetype> arch_ptr; 522typedef refptr<archetype> arch_ptr;
566typedef refptr<client> client_ptr; 523typedef refptr<client> client_ptr;
567typedef refptr<player> player_ptr; 524typedef refptr<player> player_ptr;
525typedef refptr<region> region_ptr;
568 526
569#define STRHSH_NULL 2166136261 527#define STRHSH_NULL 2166136261
570 528
571static inline uint32_t 529static inline uint32_t
572strhsh (const char *s) 530strhsh (const char *s)
… …
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) 532 // 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, 533 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution. 534 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication 535 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrently with the looping logic. 536 // runs concurrently with the looping logic.
537 // we modify the hash a bit to improve its distribution
579 uint32_t hash = STRHSH_NULL; 538 uint32_t hash = STRHSH_NULL;
580 539
581 while (*s) 540 while (*s)
582 hash = (hash ^ *s++) * 16777619U; 541 hash = (hash ^ *s++) * 16777619U;
583 542
584 return hash; 543 return hash ^ (hash >> 16);
585} 544}
586 545
587static inline uint32_t 546static inline uint32_t
588memhsh (const char *s, size_t len) 547memhsh (const char *s, size_t len)
589{ 548{
… …
704 { 663 {
705 erase (&obj); 664 erase (&obj);
706 } 665 }
707}; 666};
708 667
668/////////////////////////////////////////////////////////////////////////////
669
670// something like a vector or stack, but without
671// out of bounds checking
672template<typename T>
673struct fixed_stack
674{
675 T *data;
676 int size;
677 int max;
678
679 fixed_stack ()
680 : size (0), data (0)
681 {
682 }
683
684 fixed_stack (int max)
685 : size (0), max (max)
686 {
687 data = salloc<T> (max);
688 }
689
690 void reset (int new_max)
691 {
692 sfree (data, max);
693 size = 0;
694 max = new_max;
695 data = salloc<T> (max);
696 }
697
698 void free ()
699 {
700 sfree (data, max);
701 data = 0;
702 }
703
704 ~fixed_stack ()
705 {
706 sfree (data, max);
707 }
708
709 T &operator[](int idx)
710 {
711 return data [idx];
712 }
713
714 void push (T v)
715 {
716 data [size++] = v;
717 }
718
719 T &pop ()
720 {
721 return data [--size];
722 }
723
724 T remove (int idx)
725 {
726 T v = data [idx];
727
728 data [idx] = data [--size];
729
730 return v;
731 }
732};
733
734/////////////////////////////////////////////////////////////////////////////
735
709// basically does what strncpy should do, but appends "..." to strings exceeding length 736// basically does what strncpy should do, but appends "..." to strings exceeding length
710// returns the number of bytes actually used (including \0) 737// returns the number of bytes actually used (including \0)
711int assign (char *dst, const char *src, int maxsize); 738int assign (char *dst, const char *src, int maxsize);
712 739
713// type-safe version of assign 740// type-safe version of assign

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