ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/deliantra/server/include/util.h
(Generate patch)

Comparing deliantra/server/include/util.h (file contents):
Revision 1.79 by root, Fri Dec 19 22:47:29 2008 UTC vs.
Revision 1.92 by root, Tue Oct 20 05:57:08 2009 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 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 * 5 *
6 * Deliantra is free software: you can redistribute it and/or modify 6 * Deliantra is free software: you can redistribute it and/or modify it under
7 * it under the terms of the GNU General Public License as published by 7 * the terms of the Affero GNU General Public License as published by the
8 * the Free Software Foundation, either version 3 of the License, or 8 * Free Software Foundation, either version 3 of the License, or (at your
9 * (at your 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 GNU General Public License 16 * You should have received a copy of the Affero GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 17 * and the GNU General Public License along with this program. If not, see
18 * <http://www.gnu.org/licenses/>.
18 * 19 *
19 * 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>
20 */ 21 */
21 22
22#ifndef UTIL_H__ 23#ifndef UTIL_H__
… …
28 29
29#if __GNUC__ >= 3 30#if __GNUC__ >= 3
30# define is_constant(c) __builtin_constant_p (c) 31# define is_constant(c) __builtin_constant_p (c)
31# define expect(expr,value) __builtin_expect ((expr),(value)) 32# define expect(expr,value) __builtin_expect ((expr),(value))
32# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 33# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
34# define noinline __attribute__((__noinline__))
33#else 35#else
34# define is_constant(c) 0 36# define is_constant(c) 0
35# define expect(expr,value) (expr) 37# define expect(expr,value) (expr)
36# define prefetch(addr,rw,locality) 38# define prefetch(addr,rw,locality)
39# define noinline
37#endif 40#endif
38 41
39#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4) 42#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
40# define decltype(x) typeof(x) 43# define decltype(x) typeof(x)
41#endif 44#endif
42 45
43// put into ifs if you are very sure that the expression 46// put into ifs if you are very sure that the expression
44// is mostly true or mosty false. note that these return 47// is mostly true or mosty false. note that these return
45// booleans, not the expression. 48// booleans, not the expression.
46#define expect_false(expr) expect ((expr) != 0, 0) 49#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
47#define expect_true(expr) expect ((expr) != 0, 1) 50#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
48 51
49#include <pthread.h> 52#include <pthread.h>
50 53
51#include <cstddef> 54#include <cstddef>
52#include <cmath> 55#include <cmath>
… …
72#endif 75#endif
73 76
74// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) 77// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75#define auto(var,expr) decltype(expr) var = (expr) 78#define auto(var,expr) decltype(expr) var = (expr)
76 79
77// very ugly macro that basicaly declares and initialises a variable 80// very ugly macro that basically declares and initialises a variable
78// that is in scope for the next statement only 81// that is in scope for the next statement only
79// works only for stuff that can be assigned 0 and converts to false 82// works only for stuff that can be assigned 0 and converts to false
80// (note: works great for pointers) 83// (note: works great for pointers)
81// most ugly macro I ever wrote 84// most ugly macro I ever wrote
82#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 85#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
… …
96// as a is often a constant while b is the variable. it is still a bug, though. 99// as a is often a constant while b is the variable. it is still a bug, though.
97template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; } 100template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
98template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; } 101template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
99template<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; } 102template<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; }
100 103
101template<typename T> static inline void min_it (T &v, T m) { v = min (v, m); } 104template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); }
102template<typename T> static inline void max_it (T &v, T m) { v = max (v, m); } 105template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); }
103template<typename T> static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); } 106template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); }
104 107
105template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } 108template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
106 109
107template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); } 110template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
108template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); } 111template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
… …
116 119
117// sign0 returns -1, 0 or +1 120// sign0 returns -1, 0 or +1
118template<typename T> 121template<typename T>
119static inline T sign0 (T v) { return v ? sign (v) : 0; } 122static inline T sign0 (T v) { return v ? sign (v) : 0; }
120 123
124// div* only work correctly for div > 0
121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 125// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
122template<typename T> static inline T div (T val, T div) { return (val + div / 2) / div; } 126template<typename T> static inline T div (T val, T div)
127{
128 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
129}
123// div, round-up 130// div, round-up
124template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 131template<typename T> static inline T div_ru (T val, T div)
132{
133 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
134}
125// div, round-down 135// div, round-down
126template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 136template<typename T> static inline T div_rd (T val, T div)
137{
138 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
139}
127 140
141// lerp* only work correctly for min_in < max_in
142// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
128template<typename T> 143template<typename T>
129static inline T 144static inline T
130lerp (T val, T min_in, T max_in, T min_out, T max_out) 145lerp (T val, T min_in, T max_in, T min_out, T max_out)
131{ 146{
132 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 147 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
… …
197// on modern cpus 212// on modern cpus
198inline int 213inline int
199isqrt (int n) 214isqrt (int n)
200{ 215{
201 return (int)sqrtf ((float)n); 216 return (int)sqrtf ((float)n);
217}
218
219// this is kind of like the ^^ operator, if it would exist, without sequence point.
220// more handy than it looks like, due to the implicit !! done on its arguments
221inline bool
222logical_xor (bool a, bool b)
223{
224 return a != b;
225}
226
227inline bool
228logical_implies (bool a, bool b)
229{
230 return a <= b;
202} 231}
203 232
204// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 233// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
205#if 0 234#if 0
206// and has a max. error of 6 in the range -100..+100. 235// and has a max. error of 6 in the range -100..+100.
… …
389// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 418// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
390// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 419// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
391// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps 420// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
392struct tausworthe_random_generator 421struct tausworthe_random_generator
393{ 422{
394 // generator
395 uint32_t state [4]; 423 uint32_t state [4];
396 424
397 void operator =(const tausworthe_random_generator &src) 425 void operator =(const tausworthe_random_generator &src)
398 { 426 {
399 state [0] = src.state [0]; 427 state [0] = src.state [0];
… …
402 state [3] = src.state [3]; 430 state [3] = src.state [3];
403 } 431 }
404 432
405 void seed (uint32_t seed); 433 void seed (uint32_t seed);
406 uint32_t next (); 434 uint32_t next ();
435};
407 436
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{
408 // uniform distribution, 0 .. max (0, num - 1) 470 // uniform distribution, 0 .. max (0, num - 1)
409 uint32_t operator ()(uint32_t num) 471 uint32_t operator ()(uint32_t num)
410 { 472 {
411 return is_constant (num) 473 return !is_constant (num) ? get_range (num) // non-constant
412 ? (next () * (uint64_t)num) >> 32U 474 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
413 : get_range (num); 475 : this->next () & (num - 1); // constant, power-of-two
414 } 476 }
415 477
416 // return a number within (min .. max) 478 // return a number within (min .. max)
417 int operator () (int r_min, int r_max) 479 int operator () (int r_min, int r_max)
418 { 480 {
… …
429protected: 491protected:
430 uint32_t get_range (uint32_t r_max); 492 uint32_t get_range (uint32_t r_max);
431 int get_range (int r_min, int r_max); 493 int get_range (int r_min, int r_max);
432}; 494};
433 495
434typedef tausworthe_random_generator rand_gen; 496typedef random_number_generator<tausworthe_random_generator> rand_gen;
435 497
436extern rand_gen rndm, rmg_rndm; 498extern rand_gen rndm, rmg_rndm;
437 499
438INTERFACE_CLASS (attachable) 500INTERFACE_CLASS (attachable)
439struct refcnt_base 501struct refcnt_base
… …
508 570
509struct str_hash 571struct str_hash
510{ 572{
511 std::size_t operator ()(const char *s) const 573 std::size_t operator ()(const char *s) const
512 { 574 {
513 unsigned long hash = 0; 575#if 0
576 uint32_t hash = 0;
514 577
515 /* use the one-at-a-time hash function, which supposedly is 578 /* use the one-at-a-time hash function, which supposedly is
516 * better than the djb2-like one used by perl5.005, but 579 * better than the djb2-like one used by perl5.005, but
517 * certainly is better then the bug used here before. 580 * certainly is better then the bug used here before.
518 * see http://burtleburtle.net/bob/hash/doobs.html 581 * see http://burtleburtle.net/bob/hash/doobs.html
… …
525 } 588 }
526 589
527 hash += hash << 3; 590 hash += hash << 3;
528 hash ^= hash >> 11; 591 hash ^= hash >> 11;
529 hash += hash << 15; 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
530 604
531 return hash; 605 return hash;
532 } 606 }
533}; 607};
534 608
… …
629 erase (&obj); 703 erase (&obj);
630 } 704 }
631}; 705};
632 706
633// basically does what strncpy should do, but appends "..." to strings exceeding length 707// basically does what strncpy should do, but appends "..." to strings exceeding length
708// returns the number of bytes actually used (including \0)
634void assign (char *dst, const char *src, int maxlen); 709int assign (char *dst, const char *src, int maxsize);
635 710
636// type-safe version of assign 711// type-safe version of assign
637template<int N> 712template<int N>
638inline void assign (char (&dst)[N], const char *src) 713inline int assign (char (&dst)[N], const char *src)
639{ 714{
640 assign ((char *)&dst, src, N); 715 return assign ((char *)&dst, src, N);
641} 716}
642 717
643typedef double tstamp; 718typedef double tstamp;
644 719
645// return current time as timestamp 720// return current time as timestamp
646tstamp now (); 721tstamp now ();
647 722
648int similar_direction (int a, int b); 723int similar_direction (int a, int b);
649 724
650// like sprintf, but returns a "static" buffer 725// like v?sprintf, but returns a "static" buffer
726char *vformat (const char *format, va_list ap);
651const char *format (const char *format, ...); 727char *format (const char *format, ...);
728
729// safety-check player input which will become object->msg
730bool msg_is_safe (const char *msg);
652 731
653///////////////////////////////////////////////////////////////////////////// 732/////////////////////////////////////////////////////////////////////////////
654// threads, very very thin wrappers around pthreads 733// threads, very very thin wrappers around pthreads
655 734
656struct thread 735struct thread

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines