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Comparing deliantra/server/include/util.h (file contents):
Revision 1.92 by root, Tue Oct 20 05:57:08 2009 UTC vs.
Revision 1.112 by root, Tue Jul 6 20:15:13 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.
21 */ 21 */
22 22
23#ifndef UTIL_H__ 23#ifndef UTIL_H__
24#define UTIL_H__ 24#define UTIL_H__
25 25
26#include <compiler.h>
27
26#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0 28#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
27#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs 29#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
28#define PREFER_MALLOC 0 // use malloc and not the slice allocator 30#define PREFER_MALLOC 0 // use malloc and not the slice allocator
29
30#if __GNUC__ >= 3
31# define is_constant(c) __builtin_constant_p (c)
32# define expect(expr,value) __builtin_expect ((expr),(value))
33# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
34# define noinline __attribute__((__noinline__))
35#else
36# define is_constant(c) 0
37# define expect(expr,value) (expr)
38# define prefetch(addr,rw,locality)
39# define noinline
40#endif
41
42#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
43# define decltype(x) typeof(x)
44#endif
45
46// put into ifs if you are very sure that the expression
47// is mostly true or mosty false. note that these return
48// booleans, not the expression.
49#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
50#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
51 31
52#include <pthread.h> 32#include <pthread.h>
53 33
54#include <cstddef> 34#include <cstddef>
55#include <cmath> 35#include <cmath>
75#endif 55#endif
76 56
77// 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)
78#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
79 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
80// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
81// that is in scope for the next statement only 72// that is in scope for the next statement only
82// 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
83// (note: works great for pointers) 74// (note: works great for pointers)
84// most ugly macro I ever wrote 75// most ugly macro I ever wrote
113// sign returns -1 or +1 104// sign returns -1 or +1
114template<typename T> 105template<typename T>
115static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
116// relies on 2c representation 107// relies on 2c representation
117template<> 108template<>
118inline 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); }
119 114
120// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
121template<typename T> 116template<typename T>
122static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
118
119template<typename T, typename U>
120static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
123 121
124// div* only work correctly for div > 0 122// div* only work correctly for div > 0
125// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
126template<typename T> static inline T div (T val, T div) 124template<typename T> static inline T div (T val, T div)
127{ 125{
128 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 126 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
129} 127}
128
129template<> inline float div (float val, float div) { return val / div; }
130template<> inline double div (double val, double div) { return val / div; }
131
130// div, round-up 132// div, round-up
131template<typename T> static inline T div_ru (T val, T div) 133template<typename T> static inline T div_ru (T val, T div)
132{ 134{
133 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 135 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
134} 136}
206 int32_t d = b - a; 208 int32_t d = b - a;
207 d &= d >> 31; 209 d &= d >> 31;
208 return b - d; 210 return b - d;
209} 211}
210 212
211// this is much faster than crossfires original algorithm 213// this is much faster than crossfire's original algorithm
212// on modern cpus 214// on modern cpus
213inline int 215inline int
214isqrt (int n) 216isqrt (int n)
215{ 217{
216 return (int)sqrtf ((float)n); 218 return (int)sqrtf ((float)n);
260absdir (int d) 262absdir (int d)
261{ 263{
262 return ((d - 1) & 7) + 1; 264 return ((d - 1) & 7) + 1;
263} 265}
264 266
267// avoid ctz name because netbsd or freebsd spams it's namespace with it
268#if GCC_VERSION(3,4)
269static inline int least_significant_bit (uint32_t x)
270{
271 return __builtin_ctz (x);
272}
273#else
274int least_significant_bit (uint32_t x);
275#endif
276
277#define for_all_bits_sparse_32(mask, idxvar) \
278 for (uint32_t idxvar, mask_ = mask; \
279 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
280
265extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
266 282
267void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n) throw (std::bad_alloc);
268void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src) throw (std::bad_alloc);
269 285
413 { 429 {
414 p->~Tp (); 430 p->~Tp ();
415 } 431 }
416}; 432};
417 433
418// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
419// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
420// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
421struct tausworthe_random_generator
422{
423 uint32_t state [4];
424
425 void operator =(const tausworthe_random_generator &src)
426 {
427 state [0] = src.state [0];
428 state [1] = src.state [1];
429 state [2] = src.state [2];
430 state [3] = src.state [3];
431 }
432
433 void seed (uint32_t seed);
434 uint32_t next ();
435};
436
437// Xorshift RNGs, George Marsaglia
438// http://www.jstatsoft.org/v08/i14/paper
439// this one is about 40% faster than the tausworthe one above (i.e. not much),
440// despite the inlining, and has the issue of only creating 2**32-1 numbers.
441// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
442struct xorshift_random_generator
443{
444 uint32_t x, y;
445
446 void operator =(const xorshift_random_generator &src)
447 {
448 x = src.x;
449 y = src.y;
450 }
451
452 void seed (uint32_t seed)
453 {
454 x = seed;
455 y = seed * 69069U;
456 }
457
458 uint32_t next ()
459 {
460 uint32_t t = x ^ (x << 10);
461 x = y;
462 y = y ^ (y >> 13) ^ t ^ (t >> 10);
463 return y;
464 }
465};
466
467template<class generator>
468struct random_number_generator : generator
469{
470 // uniform distribution, 0 .. max (0, num - 1)
471 uint32_t operator ()(uint32_t num)
472 {
473 return !is_constant (num) ? get_range (num) // non-constant
474 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
475 : this->next () & (num - 1); // constant, power-of-two
476 }
477
478 // return a number within (min .. max)
479 int operator () (int r_min, int r_max)
480 {
481 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
482 ? r_min + operator ()(r_max - r_min + 1)
483 : get_range (r_min, r_max);
484 }
485
486 double operator ()()
487 {
488 return this->next () / (double)0xFFFFFFFFU;
489 }
490
491protected:
492 uint32_t get_range (uint32_t r_max);
493 int get_range (int r_min, int r_max);
494};
495
496typedef random_number_generator<tausworthe_random_generator> rand_gen;
497
498extern rand_gen rndm, rmg_rndm;
499
500INTERFACE_CLASS (attachable) 434INTERFACE_CLASS (attachable)
501struct refcnt_base 435struct refcnt_base
502{ 436{
503 typedef int refcnt_t; 437 typedef int refcnt_t;
504 mutable refcnt_t ACC (RW, refcnt); 438 mutable refcnt_t ACC (RW, refcnt);
565typedef refptr<maptile> maptile_ptr; 499typedef refptr<maptile> maptile_ptr;
566typedef refptr<object> object_ptr; 500typedef refptr<object> object_ptr;
567typedef refptr<archetype> arch_ptr; 501typedef refptr<archetype> arch_ptr;
568typedef refptr<client> client_ptr; 502typedef refptr<client> client_ptr;
569typedef refptr<player> player_ptr; 503typedef refptr<player> player_ptr;
504typedef refptr<region> region_ptr;
505
506#define STRHSH_NULL 2166136261
507
508static inline uint32_t
509strhsh (const char *s)
510{
511 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
512 // it is about twice as fast as the one-at-a-time one,
513 // with good distribution.
514 // FNV-1a is faster on many cpus because the multiplication
515 // runs concurrently with the looping logic.
516 // we modify the hash a bit to improve its distribution
517 uint32_t hash = STRHSH_NULL;
518
519 while (*s)
520 hash = (hash ^ *s++) * 16777619U;
521
522 return hash ^ (hash >> 16);
523}
524
525static inline uint32_t
526memhsh (const char *s, size_t len)
527{
528 uint32_t hash = STRHSH_NULL;
529
530 while (len--)
531 hash = (hash ^ *s++) * 16777619U;
532
533 return hash;
534}
570 535
571struct str_hash 536struct str_hash
572{ 537{
573 std::size_t operator ()(const char *s) const 538 std::size_t operator ()(const char *s) const
574 { 539 {
575#if 0
576 uint32_t hash = 0;
577
578 /* use the one-at-a-time hash function, which supposedly is
579 * better than the djb2-like one used by perl5.005, but
580 * certainly is better then the bug used here before.
581 * see http://burtleburtle.net/bob/hash/doobs.html
582 */
583 while (*s)
584 {
585 hash += *s++;
586 hash += hash << 10;
587 hash ^= hash >> 6;
588 }
589
590 hash += hash << 3;
591 hash ^= hash >> 11;
592 hash += hash << 15;
593#else
594 // 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 // with good distribution.
597 // FNV-1a is faster on many cpus because the multiplication
598 // runs concurrent with the looping logic.
599 uint32_t hash = 2166136261;
600
601 while (*s)
602 hash = (hash ^ *s++) * 16777619;
603#endif
604
605 return hash; 540 return strhsh (s);
541 }
542
543 std::size_t operator ()(const shstr &s) const
544 {
545 return strhsh (s);
606 } 546 }
607}; 547};
608 548
609struct str_equal 549struct str_equal
610{ 550{
702 { 642 {
703 erase (&obj); 643 erase (&obj);
704 } 644 }
705}; 645};
706 646
647/////////////////////////////////////////////////////////////////////////////
648
649// something like a vector or stack, but without
650// out of bounds checking
651template<typename T>
652struct fixed_stack
653{
654 T *data;
655 int size;
656 int max;
657
658 fixed_stack ()
659 : size (0), data (0)
660 {
661 }
662
663 fixed_stack (int max)
664 : size (0), max (max)
665 {
666 data = salloc<T> (max);
667 }
668
669 void reset (int new_max)
670 {
671 sfree (data, max);
672 size = 0;
673 max = new_max;
674 data = salloc<T> (max);
675 }
676
677 void free ()
678 {
679 sfree (data, max);
680 data = 0;
681 }
682
683 ~fixed_stack ()
684 {
685 sfree (data, max);
686 }
687
688 T &operator[](int idx)
689 {
690 return data [idx];
691 }
692
693 void push (T v)
694 {
695 data [size++] = v;
696 }
697
698 T &pop ()
699 {
700 return data [--size];
701 }
702
703 T remove (int idx)
704 {
705 T v = data [idx];
706
707 data [idx] = data [--size];
708
709 return v;
710 }
711};
712
713/////////////////////////////////////////////////////////////////////////////
714
707// basically does what strncpy should do, but appends "..." to strings exceeding length 715// basically does what strncpy should do, but appends "..." to strings exceeding length
708// returns the number of bytes actually used (including \0) 716// returns the number of bytes actually used (including \0)
709int assign (char *dst, const char *src, int maxsize); 717int assign (char *dst, const char *src, int maxsize);
710 718
711// type-safe version of assign 719// type-safe version of assign
722 730
723int similar_direction (int a, int b); 731int similar_direction (int a, int b);
724 732
725// like v?sprintf, but returns a "static" buffer 733// like v?sprintf, but returns a "static" buffer
726char *vformat (const char *format, va_list ap); 734char *vformat (const char *format, va_list ap);
727char *format (const char *format, ...); 735char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
728 736
729// safety-check player input which will become object->msg 737// safety-check player input which will become object->msg
730bool msg_is_safe (const char *msg); 738bool msg_is_safe (const char *msg);
731 739
732///////////////////////////////////////////////////////////////////////////// 740/////////////////////////////////////////////////////////////////////////////

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