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Revision 1.99 by root, Fri Apr 9 02:45:16 2010 UTC vs.
Revision 1.122 by root, Mon Nov 12 02:39:51 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__
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}
217#if 0 237#if 0
218// and has a max. error of 6 in the range -100..+100. 238// and has a max. error of 6 in the range -100..+100.
219#else 239#else
220// and has a max. error of 9 in the range -100..+100. 240// and has a max. error of 9 in the range -100..+100.
221#endif 241#endif
222inline int 242inline int
223idistance (int dx, int dy) 243idistance (int dx, int dy)
224{ 244{
225 unsigned int dx_ = abs (dx); 245 unsigned int dx_ = abs (dx);
226 unsigned int dy_ = abs (dy); 246 unsigned int dy_ = abs (dy);
227 247
228#if 0 248#if 0
229 return dx_ > dy_ 249 return dx_ > dy_
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 */
284 if (expect_true (ptr)) 324 if (expect_true (ptr))
285 { 325 {
286 slice_alloc -= n * sizeof (T); 326 slice_alloc -= n * sizeof (T);
287 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T)); 327 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
288 g_slice_free1 (n * sizeof (T), (void *)ptr); 328 g_slice_free1 (n * sizeof (T), (void *)ptr);
289 assert (slice_alloc >= 0);//D
290 } 329 }
291} 330}
292 331
293// nulls the pointer 332// nulls the pointer
294template<typename T> 333template<typename T>
368 typedef const Tp *const_pointer; 407 typedef const Tp *const_pointer;
369 typedef Tp &reference; 408 typedef Tp &reference;
370 typedef const Tp &const_reference; 409 typedef const Tp &const_reference;
371 typedef Tp value_type; 410 typedef Tp value_type;
372 411
373 template <class U> 412 template <class U>
374 struct rebind 413 struct rebind
375 { 414 {
376 typedef slice_allocator<U> other; 415 typedef slice_allocator<U> other;
377 }; 416 };
378 417
410 { 449 {
411 p->~Tp (); 450 p->~Tp ();
412 } 451 }
413}; 452};
414 453
415// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 454// basically a memory area, but refcounted
416// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 455struct refcnt_buf
417// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
418struct tausworthe_random_generator
419{ 456{
420 uint32_t state [4]; 457 char *data;
421 458
422 void operator =(const tausworthe_random_generator &src) 459 refcnt_buf (size_t size = 0);
423 { 460 refcnt_buf (void *data, size_t size);
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 }
429 461
430 void seed (uint32_t seed); 462 refcnt_buf (const refcnt_buf &src)
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 { 463 {
445 x = src.x; 464 data = src.data;
446 y = src.y; 465 inc ();
447 } 466 }
448 467
449 void seed (uint32_t seed) 468 ~refcnt_buf ();
450 {
451 x = seed;
452 y = seed * 69069U;
453 }
454 469
455 uint32_t next () 470 refcnt_buf &operator =(const refcnt_buf &src);
471
472 operator char *()
456 { 473 {
457 uint32_t t = x ^ (x << 10);
458 x = y;
459 y = y ^ (y >> 13) ^ t ^ (t >> 10);
460 return y; 474 return data;
461 } 475 }
462};
463 476
464template<class generator> 477 size_t size () const
465struct random_number_generator : generator
466{
467 // uniform distribution, 0 .. max (0, num - 1)
468 uint32_t operator ()(uint32_t num)
469 { 478 {
470 return !is_constant (num) ? get_range (num) // non-constant 479 return _size ();
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 (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 double operator ()()
484 {
485 return this->next () / (double)0xFFFFFFFFU;
486 } 480 }
487 481
488protected: 482protected:
489 uint32_t get_range (uint32_t r_max); 483 enum {
490 int get_range (int r_min, int r_max); 484 overhead = sizeof (uint32_t) * 2
491}; 485 };
492 486
493typedef random_number_generator<tausworthe_random_generator> rand_gen; 487 uint32_t &_size () const
488 {
489 return ((unsigned int *)data)[-2];
490 }
494 491
495extern 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};
496 517
497INTERFACE_CLASS (attachable) 518INTERFACE_CLASS (attachable)
498struct refcnt_base 519struct refcnt_base
499{ 520{
500 typedef int refcnt_t; 521 typedef int refcnt_t;
562typedef refptr<maptile> maptile_ptr; 583typedef refptr<maptile> maptile_ptr;
563typedef refptr<object> object_ptr; 584typedef refptr<object> object_ptr;
564typedef refptr<archetype> arch_ptr; 585typedef refptr<archetype> arch_ptr;
565typedef refptr<client> client_ptr; 586typedef refptr<client> client_ptr;
566typedef refptr<player> player_ptr; 587typedef refptr<player> player_ptr;
588typedef refptr<region> region_ptr;
567 589
568#define STRHSH_NULL 2166136261 590#define STRHSH_NULL 2166136261
569 591
570static inline uint32_t 592static inline uint32_t
571strhsh (const char *s) 593strhsh (const char *s)
573 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) 595 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
574 // 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,
575 // with good distribution. 597 // with good distribution.
576 // FNV-1a is faster on many cpus because the multiplication 598 // FNV-1a is faster on many cpus because the multiplication
577 // runs concurrently with the looping logic. 599 // runs concurrently with the looping logic.
600 // we modify the hash a bit to improve its distribution
578 uint32_t hash = STRHSH_NULL; 601 uint32_t hash = STRHSH_NULL;
579 602
580 while (*s) 603 while (*s)
581 hash = (hash ^ *s++) * 16777619U; 604 hash = (hash ^ *s++) * 16777619U;
582 605
583 return hash; 606 return hash ^ (hash >> 16);
584} 607}
585 608
586static inline uint32_t 609static inline uint32_t
587memhsh (const char *s, size_t len) 610memhsh (const char *s, size_t len)
588{ 611{
589 uint32_t hash = STRHSH_NULL; 612 uint32_t hash = STRHSH_NULL;
590 613
591 while (len--) 614 while (len--)
592 hash = (hash ^ *s++) * 16777619U; 615 hash = (hash ^ *s++) * 16777619U;
593 616
594 return hash; 617 return hash;
595} 618}
638 } 661 }
639}; 662};
640 663
641// This container blends advantages of linked lists 664// This container blends advantages of linked lists
642// (efficiency) with vectors (random access) by 665// (efficiency) with vectors (random access) by
643// by using an unordered vector and storing the vector 666// using an unordered vector and storing the vector
644// index inside the object. 667// index inside the object.
645// 668//
646// + memory-efficient on most 64 bit archs 669// + memory-efficient on most 64 bit archs
647// + O(1) insert/remove 670// + O(1) insert/remove
648// + free unique (but varying) id for inserted objects 671// + free unique (but varying) id for inserted objects
685 insert (&obj); 708 insert (&obj);
686 } 709 }
687 710
688 void erase (T *obj) 711 void erase (T *obj)
689 { 712 {
690 unsigned int pos = obj->*indexmember; 713 object_vector_index pos = obj->*indexmember;
691 obj->*indexmember = 0; 714 obj->*indexmember = 0;
692 715
693 if (pos < this->size ()) 716 if (pos < this->size ())
694 { 717 {
695 (*this)[pos - 1] = (*this)[this->size () - 1]; 718 (*this)[pos - 1] = (*this)[this->size () - 1];
703 { 726 {
704 erase (&obj); 727 erase (&obj);
705 } 728 }
706}; 729};
707 730
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
708// 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
709// returns the number of bytes actually used (including \0) 800// returns the number of bytes actually used (including \0)
710int assign (char *dst, const char *src, int maxsize); 801int assign (char *dst, const char *src, int maxsize);
711 802
712// type-safe version of assign 803// type-safe version of assign

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