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Comparing deliantra/server/include/util.h (file contents):
Revision 1.108 by root, Wed May 26 19:11:43 2010 UTC vs.
Revision 1.121 by root, Sun Nov 11 01:27:44 2012 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 (©) 2005,2006,2007,2008,2009,2010,2011,2012 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.
10 * 10 *
11 * This program is distributed in the hope that it will be useful, 11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details. 14 * GNU General Public License for more details.
15 * 15 *
16 * You should have received a copy of the Affero GNU General Public License 16 * You should have received a copy of the Affero GNU General Public License
17 * and the GNU General Public License along with this program. If not, see 17 * and the GNU General Public License along with this program. If not, see
18 * <http://www.gnu.org/licenses/>. 18 * <http://www.gnu.org/licenses/>.
19 * 19 *
20 * The authors can be reached via e-mail to <support@deliantra.net> 20 * The authors can be reached via e-mail to <support@deliantra.net>
21 */ 21 */
22 22
23#ifndef UTIL_H__ 23#ifndef UTIL_H__
24#define UTIL_H__ 24#define UTIL_H__
86void cleanup (const char *cause, bool make_core = false); 86void cleanup (const char *cause, bool make_core = false);
87void fork_abort (const char *msg); 87void fork_abort (const char *msg);
88 88
89// 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,
90// 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.
91template<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; }
92template<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; }
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; } 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; }
94 94
95template<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); }
96template<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); }
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); } 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); }
114 114
115// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
116template<typename T> 116template<typename T>
117static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
118 118
119//clashes with C++0x
119template<typename T, typename U> 120template<typename T, typename U>
120static 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; }
121 122
122// div* only work correctly for div > 0 123// div* only work correctly for div > 0
123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 124// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
251#else 252#else
252 return dx_ + dy_ - min (dx_, dy_) * 5 / 8; 253 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
253#endif 254#endif
254} 255}
255 256
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
256/* 277/*
257 * absdir(int): Returns a number between 1 and 8, which represent 278 * absdir(int): Returns a number between 1 and 8, which represent
258 * the "absolute" direction of a number (it actually takes care of 279 * the "absolute" direction of a number (it actually takes care of
259 * "overflow" in previous calculations of a direction). 280 * "overflow" in previous calculations of a direction).
260 */ 281 */
303 if (expect_true (ptr)) 324 if (expect_true (ptr))
304 { 325 {
305 slice_alloc -= n * sizeof (T); 326 slice_alloc -= n * sizeof (T);
306 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T)); 327 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
307 g_slice_free1 (n * sizeof (T), (void *)ptr); 328 g_slice_free1 (n * sizeof (T), (void *)ptr);
308 assert (slice_alloc >= 0);//D
309 } 329 }
310} 330}
311 331
312// nulls the pointer 332// nulls the pointer
313template<typename T> 333template<typename T>
429 { 449 {
430 p->~Tp (); 450 p->~Tp ();
431 } 451 }
432}; 452};
433 453
434// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 454// basically a memory area, but refcounted
435// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 455struct refcnt_buf
436// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
437struct tausworthe_random_generator
438{ 456{
439 uint32_t state [4]; 457 char *data;
440 458
441 void operator =(const tausworthe_random_generator &src) 459 refcnt_buf (size_t size = 0);
442 { 460 refcnt_buf (void *data, size_t size);
443 state [0] = src.state [0];
444 state [1] = src.state [1];
445 state [2] = src.state [2];
446 state [3] = src.state [3];
447 }
448 461
449 void seed (uint32_t seed); 462 refcnt_buf (const refcnt_buf &src)
450 uint32_t next ();
451};
452
453// Xorshift RNGs, George Marsaglia
454// http://www.jstatsoft.org/v08/i14/paper
455// this one is about 40% faster than the tausworthe one above (i.e. not much),
456// despite the inlining, and has the issue of only creating 2**32-1 numbers.
457// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
458struct xorshift_random_generator
459{
460 uint32_t x, y;
461
462 void operator =(const xorshift_random_generator &src)
463 { 463 {
464 x = src.x; 464 data = src.data;
465 y = src.y; 465 inc ();
466 } 466 }
467 467
468 void seed (uint32_t seed) 468 ~refcnt_buf ();
469 {
470 x = seed;
471 y = seed * 69069U;
472 }
473 469
474 uint32_t next () 470 refcnt_buf &operator =(const refcnt_buf &src);
471
472 operator char *()
475 { 473 {
476 uint32_t t = x ^ (x << 10);
477 x = y;
478 y = y ^ (y >> 13) ^ t ^ (t >> 10);
479 return y; 474 return data;
480 } 475 }
481};
482 476
483template<class generator> 477 size_t size () const
484struct random_number_generator : generator
485{
486 // uniform distribution, [0 .. num - 1]
487 uint32_t operator ()(uint32_t num)
488 { 478 {
489 return !is_constant (num) ? get_range (num) // non-constant 479 return _size ();
490 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
491 : this->next () & (num - 1); // constant, power-of-two
492 }
493
494 // return a number within the closed interval [min .. max]
495 int operator () (int r_min, int r_max)
496 {
497 return is_constant (r_min <= r_max) && r_min <= r_max
498 ? r_min + operator ()(r_max - r_min + 1)
499 : get_range (r_min, r_max);
500 }
501
502 // return a number within the half-open interval [0..1[
503 double operator ()()
504 {
505 return this->next () / (double)0x100000000ULL;
506 } 480 }
507 481
508protected: 482protected:
509 uint32_t get_range (uint32_t r_max); 483 enum {
510 int get_range (int r_min, int r_max); 484 overhead = sizeof (uint32_t) * 2
511}; 485 };
512 486
513typedef random_number_generator<tausworthe_random_generator> rand_gen; 487 uint32_t &_size () const
488 {
489 return ((unsigned int *)data)[-2];
490 }
514 491
515extern rand_gen rndm, rmg_rndm; 492 uint32_t &_refcnt () const
493 {
494 return ((unsigned int *)data)[-1];
495 }
496
497 void _alloc (uint32_t size)
498 {
499 data = ((char *)salloc<char> (size + overhead)) + overhead;
500 _size () = size;
501 _refcnt () = 1;
502 }
503
504 void _dealloc ();
505
506 void inc ()
507 {
508 ++_refcnt ();
509 }
510
511 void dec ()
512 {
513 if (!--_refcnt ())
514 _dealloc ();
515 }
516};
516 517
517INTERFACE_CLASS (attachable) 518INTERFACE_CLASS (attachable)
518struct refcnt_base 519struct refcnt_base
519{ 520{
520 typedef int refcnt_t; 521 typedef int refcnt_t;
594 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) 595 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
595 // it is about twice as fast as the one-at-a-time one, 596 // it is about twice as fast as the one-at-a-time one,
596 // with good distribution. 597 // with good distribution.
597 // FNV-1a is faster on many cpus because the multiplication 598 // FNV-1a is faster on many cpus because the multiplication
598 // runs concurrently with the looping logic. 599 // runs concurrently with the looping logic.
600 // we modify the hash a bit to improve its distribution
599 uint32_t hash = STRHSH_NULL; 601 uint32_t hash = STRHSH_NULL;
600 602
601 while (*s) 603 while (*s)
602 hash = (hash ^ *s++) * 16777619U; 604 hash = (hash ^ *s++) * 16777619U;
603 605
604 return hash; 606 return hash ^ (hash >> 16);
605} 607}
606 608
607static inline uint32_t 609static inline uint32_t
608memhsh (const char *s, size_t len) 610memhsh (const char *s, size_t len)
609{ 611{
659 } 661 }
660}; 662};
661 663
662// This container blends advantages of linked lists 664// This container blends advantages of linked lists
663// (efficiency) with vectors (random access) by 665// (efficiency) with vectors (random access) by
664// by using an unordered vector and storing the vector 666// using an unordered vector and storing the vector
665// index inside the object. 667// index inside the object.
666// 668//
667// + memory-efficient on most 64 bit archs 669// + memory-efficient on most 64 bit archs
668// + O(1) insert/remove 670// + O(1) insert/remove
669// + free unique (but varying) id for inserted objects 671// + free unique (but varying) id for inserted objects
706 insert (&obj); 708 insert (&obj);
707 } 709 }
708 710
709 void erase (T *obj) 711 void erase (T *obj)
710 { 712 {
711 unsigned int pos = obj->*indexmember; 713 object_vector_index pos = obj->*indexmember;
712 obj->*indexmember = 0; 714 obj->*indexmember = 0;
713 715
714 if (pos < this->size ()) 716 if (pos < this->size ())
715 { 717 {
716 (*this)[pos - 1] = (*this)[this->size () - 1]; 718 (*this)[pos - 1] = (*this)[this->size () - 1];
724 { 726 {
725 erase (&obj); 727 erase (&obj);
726 } 728 }
727}; 729};
728 730
731/////////////////////////////////////////////////////////////////////////////
732
733// something like a vector or stack, but without
734// out of bounds checking
735template<typename T>
736struct fixed_stack
737{
738 T *data;
739 int size;
740 int max;
741
742 fixed_stack ()
743 : size (0), data (0)
744 {
745 }
746
747 fixed_stack (int max)
748 : size (0), max (max)
749 {
750 data = salloc<T> (max);
751 }
752
753 void reset (int new_max)
754 {
755 sfree (data, max);
756 size = 0;
757 max = new_max;
758 data = salloc<T> (max);
759 }
760
761 void free ()
762 {
763 sfree (data, max);
764 data = 0;
765 }
766
767 ~fixed_stack ()
768 {
769 sfree (data, max);
770 }
771
772 T &operator[](int idx)
773 {
774 return data [idx];
775 }
776
777 void push (T v)
778 {
779 data [size++] = v;
780 }
781
782 T &pop ()
783 {
784 return data [--size];
785 }
786
787 T remove (int idx)
788 {
789 T v = data [idx];
790
791 data [idx] = data [--size];
792
793 return v;
794 }
795};
796
797/////////////////////////////////////////////////////////////////////////////
798
729// basically does what strncpy should do, but appends "..." to strings exceeding length 799// basically does what strncpy should do, but appends "..." to strings exceeding length
730// returns the number of bytes actually used (including \0) 800// returns the number of bytes actually used (including \0)
731int assign (char *dst, const char *src, int maxsize); 801int assign (char *dst, const char *src, int maxsize);
732 802
733// type-safe version of assign 803// type-safe version of assign

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