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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 1.98 by root, Fri Apr 2 03:41:24 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 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__
23#define UTIL_H__ 24#define UTIL_H__
24 25
26#include <compiler.h>
27
25#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0 28#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs 29#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27#define PREFER_MALLOC 0 // use malloc and not the slice allocator 30#define PREFER_MALLOC 0 // use malloc and not the slice allocator
28
29#if __GNUC__ >= 3
30# define is_constant(c) __builtin_constant_p (c)
31# define expect(expr,value) __builtin_expect ((expr),(value))
32# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
33#else
34# define is_constant(c) 0
35# define expect(expr,value) (expr)
36# define prefetch(addr,rw,locality)
37#endif
38
39#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
40# define decltype(x) typeof(x)
41#endif
42
43// put into ifs if you are very sure that the expression
44// is mostly true or mosty false. note that these return
45// booleans, not the expression.
46#define expect_false(expr) expect ((expr) != 0, 0)
47#define expect_true(expr) expect ((expr) != 0, 1)
48 31
49#include <pthread.h> 32#include <pthread.h>
50 33
51#include <cstddef> 34#include <cstddef>
52#include <cmath> 35#include <cmath>
… …
116 99
117// sign0 returns -1, 0 or +1 100// sign0 returns -1, 0 or +1
118template<typename T> 101template<typename T>
119static inline T sign0 (T v) { return v ? sign (v) : 0; } 102static inline T sign0 (T v) { return v ? sign (v) : 0; }
120 103
104// div* only work correctly for div > 0
121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 105// 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; } 106template<typename T> static inline T div (T val, T div)
107{
108 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
109}
123// div, round-up 110// div, round-up
124template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 111template<typename T> static inline T div_ru (T val, T div)
112{
113 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
114}
125// div, round-down 115// div, round-down
126template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 116template<typename T> static inline T div_rd (T val, T div)
117{
118 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
119}
127 120
121// lerp* only work correctly for min_in < max_in
122// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
128template<typename T> 123template<typename T>
129static inline T 124static inline T
130lerp (T val, T min_in, T max_in, T min_out, T max_out) 125lerp (T val, T min_in, T max_in, T min_out, T max_out)
131{ 126{
132 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 127 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
… …
191 int32_t d = b - a; 186 int32_t d = b - a;
192 d &= d >> 31; 187 d &= d >> 31;
193 return b - d; 188 return b - d;
194} 189}
195 190
196// this is much faster than crossfires original algorithm 191// this is much faster than crossfire's original algorithm
197// on modern cpus 192// on modern cpus
198inline int 193inline int
199isqrt (int n) 194isqrt (int n)
200{ 195{
201 return (int)sqrtf ((float)n); 196 return (int)sqrtf ((float)n);
197}
198
199// this is kind of like the ^^ operator, if it would exist, without sequence point.
200// more handy than it looks like, due to the implicit !! done on its arguments
201inline bool
202logical_xor (bool a, bool b)
203{
204 return a != b;
205}
206
207inline bool
208logical_implies (bool a, bool b)
209{
210 return a <= b;
202} 211}
203 212
204// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 213// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
205#if 0 214#if 0
206// and has a max. error of 6 in the range -100..+100. 215// and has a max. error of 6 in the range -100..+100.
… …
231absdir (int d) 240absdir (int d)
232{ 241{
233 return ((d - 1) & 7) + 1; 242 return ((d - 1) & 7) + 1;
234} 243}
235 244
245// avoid ctz name because netbsd or freebsd spams it's namespace with it
246#if GCC_VERSION(3,4)
247static inline int least_significant_bit (uint32_t x)
248{
249 return __builtin_ctz (x);
250}
251#else
252int least_significant_bit (uint32_t x);
253#endif
254
255#define for_all_bits_sparse_32(mask, idxvar) \
256 for (uint32_t idxvar, mask_ = mask; \
257 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
258
236extern ssize_t slice_alloc; // statistics 259extern ssize_t slice_alloc; // statistics
237 260
238void *salloc_ (int n) throw (std::bad_alloc); 261void *salloc_ (int n) throw (std::bad_alloc);
239void *salloc_ (int n, void *src) throw (std::bad_alloc); 262void *salloc_ (int n, void *src) throw (std::bad_alloc);
240 263
… …
407 430
408// Xorshift RNGs, George Marsaglia 431// Xorshift RNGs, George Marsaglia
409// http://www.jstatsoft.org/v08/i14/paper 432// http://www.jstatsoft.org/v08/i14/paper
410// this one is about 40% faster than the tausworthe one above (i.e. not much), 433// 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. 434// despite the inlining, and has the issue of only creating 2**32-1 numbers.
435// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
412struct xorshift_random_generator 436struct xorshift_random_generator
413{ 437{
414 uint32_t x, y; 438 uint32_t x, y;
415 439
416 void operator =(const xorshift_random_generator &src) 440 void operator =(const xorshift_random_generator &src)
… …
536typedef refptr<object> object_ptr; 560typedef refptr<object> object_ptr;
537typedef refptr<archetype> arch_ptr; 561typedef refptr<archetype> arch_ptr;
538typedef refptr<client> client_ptr; 562typedef refptr<client> client_ptr;
539typedef refptr<player> player_ptr; 563typedef refptr<player> player_ptr;
540 564
565#define STRHSH_NULL 2166136261
566
567static inline uint32_t
568strhsh (const char *s)
569{
570 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
571 // it is about twice as fast as the one-at-a-time one,
572 // with good distribution.
573 // FNV-1a is faster on many cpus because the multiplication
574 // runs concurrently with the looping logic.
575 uint32_t hash = STRHSH_NULL;
576
577 while (*s)
578 hash = (hash ^ *s++) * 16777619U;
579
580 return hash;
581}
582
583static inline uint32_t
584memhsh (const char *s, size_t len)
585{
586 uint32_t hash = STRHSH_NULL;
587
588 while (len--)
589 hash = (hash ^ *s++) * 16777619U;
590
591 return hash;
592}
593
541struct str_hash 594struct str_hash
542{ 595{
543 std::size_t operator ()(const char *s) const 596 std::size_t operator ()(const char *s) const
544 { 597 {
545 unsigned long hash = 0;
546
547 /* use the one-at-a-time hash function, which supposedly is
548 * better than the djb2-like one used by perl5.005, but
549 * certainly is better then the bug used here before.
550 * see http://burtleburtle.net/bob/hash/doobs.html
551 */
552 while (*s)
553 {
554 hash += *s++;
555 hash += hash << 10;
556 hash ^= hash >> 6;
557 }
558
559 hash += hash << 3;
560 hash ^= hash >> 11;
561 hash += hash << 15;
562
563 return hash; 598 return strhsh (s);
599 }
600
601 std::size_t operator ()(const shstr &s) const
602 {
603 return strhsh (s);
564 } 604 }
565}; 605};
566 606
567struct str_equal 607struct str_equal
568{ 608{
… …
661 erase (&obj); 701 erase (&obj);
662 } 702 }
663}; 703};
664 704
665// basically does what strncpy should do, but appends "..." to strings exceeding length 705// basically does what strncpy should do, but appends "..." to strings exceeding length
706// returns the number of bytes actually used (including \0)
666void assign (char *dst, const char *src, int maxlen); 707int assign (char *dst, const char *src, int maxsize);
667 708
668// type-safe version of assign 709// type-safe version of assign
669template<int N> 710template<int N>
670inline void assign (char (&dst)[N], const char *src) 711inline int assign (char (&dst)[N], const char *src)
671{ 712{
672 assign ((char *)&dst, src, N); 713 return assign ((char *)&dst, src, N);
673} 714}
674 715
675typedef double tstamp; 716typedef double tstamp;
676 717
677// return current time as timestamp 718// return current time as timestamp
678tstamp now (); 719tstamp now ();
679 720
680int similar_direction (int a, int b); 721int similar_direction (int a, int b);
681 722
682// like sprintf, but returns a "static" buffer 723// like v?sprintf, but returns a "static" buffer
683const char *format (const char *format, ...); 724char *vformat (const char *format, va_list ap);
725char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
726
727// safety-check player input which will become object->msg
728bool msg_is_safe (const char *msg);
684 729
685///////////////////////////////////////////////////////////////////////////// 730/////////////////////////////////////////////////////////////////////////////
686// threads, very very thin wrappers around pthreads 731// threads, very very thin wrappers around pthreads
687 732
688struct thread 733struct thread

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