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Comparing deliantra/server/include/util.h (file contents):
Revision 1.83 by root, Tue Dec 30 07:24:16 2008 UTC vs.
Revision 1.91 by root, Thu Oct 15 21:09:32 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>
… …
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);
… …
407 422
408// Xorshift RNGs, George Marsaglia 423// Xorshift RNGs, George Marsaglia
409// http://www.jstatsoft.org/v08/i14/paper 424// http://www.jstatsoft.org/v08/i14/paper
410// this one is about 40% faster than the tausworthe one above (i.e. not much), 425// this one is about 40% faster than the tausworthe one above (i.e. not much),
411// despite the inlining, and has the issue of only creating 2**32-1 numbers. 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
412struct xorshift_random_generator 428struct xorshift_random_generator
413{ 429{
414 uint32_t x, y; 430 uint32_t x, y;
415 431
416 void operator =(const xorshift_random_generator &src) 432 void operator =(const xorshift_random_generator &src)
… …
540 556
541struct str_hash 557struct str_hash
542{ 558{
543 std::size_t operator ()(const char *s) const 559 std::size_t operator ()(const char *s) const
544 { 560 {
545 unsigned long hash = 0; 561#if 0
562 uint32_t hash = 0;
546 563
547 /* use the one-at-a-time hash function, which supposedly is 564 /* use the one-at-a-time hash function, which supposedly is
548 * better than the djb2-like one used by perl5.005, but 565 * better than the djb2-like one used by perl5.005, but
549 * certainly is better then the bug used here before. 566 * certainly is better then the bug used here before.
550 * see http://burtleburtle.net/bob/hash/doobs.html 567 * see http://burtleburtle.net/bob/hash/doobs.html
… …
557 } 574 }
558 575
559 hash += hash << 3; 576 hash += hash << 3;
560 hash ^= hash >> 11; 577 hash ^= hash >> 11;
561 hash += hash << 15; 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
562 590
563 return hash; 591 return hash;
564 } 592 }
565}; 593};
566 594
… …
661 erase (&obj); 689 erase (&obj);
662 } 690 }
663}; 691};
664 692
665// basically does what strncpy should do, but appends "..." to strings exceeding length 693// basically does what strncpy should do, but appends "..." to strings exceeding length
694// returns the number of bytes actually used (including \0)
666void assign (char *dst, const char *src, int maxlen); 695int assign (char *dst, const char *src, int maxsize);
667 696
668// type-safe version of assign 697// type-safe version of assign
669template<int N> 698template<int N>
670inline void assign (char (&dst)[N], const char *src) 699inline int assign (char (&dst)[N], const char *src)
671{ 700{
672 assign ((char *)&dst, src, N); 701 return assign ((char *)&dst, src, N);
673} 702}
674 703
675typedef double tstamp; 704typedef double tstamp;
676 705
677// return current time as timestamp 706// return current time as timestamp
678tstamp now (); 707tstamp now ();
679 708
680int similar_direction (int a, int b); 709int similar_direction (int a, int b);
681 710
682// like sprintf, but returns a "static" buffer 711// like v?sprintf, but returns a "static" buffer
712char *vformat (const char *format, va_list ap);
683const char *format (const char *format, ...); 713char *format (const char *format, ...);
714
715// safety-check player input which will become object->msg
716bool msg_is_safe (const char *msg);
684 717
685///////////////////////////////////////////////////////////////////////////// 718/////////////////////////////////////////////////////////////////////////////
686// threads, very very thin wrappers around pthreads 719// threads, very very thin wrappers around pthreads
687 720
688struct thread 721struct thread

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