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Comparing deliantra/server/include/util.h (file contents):
Revision 1.90 by root, Mon Oct 12 14:00:58 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);
219}
220
221// this is kind of like the ^^ operator, if it would exist, without sequence point.
222// more handy than it looks like, due to the implicit !! done on its arguments
223inline bool
224logical_xor (bool a, bool b)
225{
226 return a != b;
227}
228
229inline bool
230logical_implies (bool a, bool b)
231{
232 return a <= b;
217} 233}
218 234
219// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 235// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
220#if 0 236#if 0
221// and has a max. error of 6 in the range -100..+100. 237// and has a max. error of 6 in the range -100..+100.
… …
246absdir (int d) 262absdir (int d)
247{ 263{
248 return ((d - 1) & 7) + 1; 264 return ((d - 1) & 7) + 1;
249} 265}
250 266
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
251extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
252 282
253void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n) throw (std::bad_alloc);
254void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src) throw (std::bad_alloc);
255 285
… …
399 { 429 {
400 p->~Tp (); 430 p->~Tp ();
401 } 431 }
402}; 432};
403 433
404// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
405// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
406// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
407struct tausworthe_random_generator
408{
409 uint32_t state [4];
410
411 void operator =(const tausworthe_random_generator &src)
412 {
413 state [0] = src.state [0];
414 state [1] = src.state [1];
415 state [2] = src.state [2];
416 state [3] = src.state [3];
417 }
418
419 void seed (uint32_t seed);
420 uint32_t next ();
421};
422
423// Xorshift RNGs, George Marsaglia
424// http://www.jstatsoft.org/v08/i14/paper
425// this one is about 40% faster than the tausworthe one above (i.e. not much),
426// despite the inlining, and has the issue of only creating 2**32-1 numbers.
427// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
428struct xorshift_random_generator
429{
430 uint32_t x, y;
431
432 void operator =(const xorshift_random_generator &src)
433 {
434 x = src.x;
435 y = src.y;
436 }
437
438 void seed (uint32_t seed)
439 {
440 x = seed;
441 y = seed * 69069U;
442 }
443
444 uint32_t next ()
445 {
446 uint32_t t = x ^ (x << 10);
447 x = y;
448 y = y ^ (y >> 13) ^ t ^ (t >> 10);
449 return y;
450 }
451};
452
453template<class generator>
454struct random_number_generator : generator
455{
456 // uniform distribution, 0 .. max (0, num - 1)
457 uint32_t operator ()(uint32_t num)
458 {
459 return !is_constant (num) ? get_range (num) // non-constant
460 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
461 : this->next () & (num - 1); // constant, power-of-two
462 }
463
464 // return a number within (min .. max)
465 int operator () (int r_min, int r_max)
466 {
467 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
468 ? r_min + operator ()(r_max - r_min + 1)
469 : get_range (r_min, r_max);
470 }
471
472 double operator ()()
473 {
474 return this->next () / (double)0xFFFFFFFFU;
475 }
476
477protected:
478 uint32_t get_range (uint32_t r_max);
479 int get_range (int r_min, int r_max);
480};
481
482typedef random_number_generator<tausworthe_random_generator> rand_gen;
483
484extern rand_gen rndm, rmg_rndm;
485
486INTERFACE_CLASS (attachable) 434INTERFACE_CLASS (attachable)
487struct refcnt_base 435struct refcnt_base
488{ 436{
489 typedef int refcnt_t; 437 typedef int refcnt_t;
490 mutable refcnt_t ACC (RW, refcnt); 438 mutable refcnt_t ACC (RW, refcnt);
… …
551typedef refptr<maptile> maptile_ptr; 499typedef refptr<maptile> maptile_ptr;
552typedef refptr<object> object_ptr; 500typedef refptr<object> object_ptr;
553typedef refptr<archetype> arch_ptr; 501typedef refptr<archetype> arch_ptr;
554typedef refptr<client> client_ptr; 502typedef refptr<client> client_ptr;
555typedef 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}
556 535
557struct str_hash 536struct str_hash
558{ 537{
559 std::size_t operator ()(const char *s) const 538 std::size_t operator ()(const char *s) const
560 { 539 {
561#if 0
562 uint32_t hash = 0;
563
564 /* use the one-at-a-time hash function, which supposedly is
565 * better than the djb2-like one used by perl5.005, but
566 * certainly is better then the bug used here before.
567 * see http://burtleburtle.net/bob/hash/doobs.html
568 */
569 while (*s)
570 {
571 hash += *s++;
572 hash += hash << 10;
573 hash ^= hash >> 6;
574 }
575
576 hash += hash << 3;
577 hash ^= hash >> 11;
578 hash += hash << 15;
579#else
580 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
581 // it is about twice as fast as the one-at-a-time one,
582 // with good distribution.
583 // FNV-1a is faster on many cpus because the multiplication
584 // runs concurrent with the looping logic.
585 uint32_t hash = 2166136261;
586
587 while (*s)
588 hash = (hash ^ *s++) * 16777619;
589#endif
590
591 return hash; 540 return strhsh (s);
541 }
542
543 std::size_t operator ()(const shstr &s) const
544 {
545 return strhsh (s);
592 } 546 }
593}; 547};
594 548
595struct str_equal 549struct str_equal
596{ 550{
… …
688 { 642 {
689 erase (&obj); 643 erase (&obj);
690 } 644 }
691}; 645};
692 646
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
693// 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
694// returns the number of bytes actually used (including \0) 716// returns the number of bytes actually used (including \0)
695int assign (char *dst, const char *src, int maxsize); 717int assign (char *dst, const char *src, int maxsize);
696 718
697// type-safe version of assign 719// type-safe version of assign
… …
706// return current time as timestamp 728// return current time as timestamp
707tstamp now (); 729tstamp now ();
708 730
709int similar_direction (int a, int b); 731int similar_direction (int a, int b);
710 732
711// like sprintf, but returns a "static" buffer 733// like v?sprintf, but returns a "static" buffer
712const char *format (const char *format, ...); 734char *vformat (const char *format, va_list ap);
735char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
713 736
714// safety-check player input which will become object->msg 737// safety-check player input which will become object->msg
715bool msg_is_safe (const char *msg); 738bool msg_is_safe (const char *msg);
716 739
717///////////////////////////////////////////////////////////////////////////// 740/////////////////////////////////////////////////////////////////////////////

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