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Comparing deliantra/server/include/util.h (file contents):
Revision 1.84 by root, Wed Dec 31 17:35:37 2008 UTC vs.
Revision 1.100 by root, Thu Apr 22 13:01:58 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) ? 1 : 0, 0)
47#define expect_true(expr) expect ((expr) ? 1 : 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
104template<typename T, typename U>
105static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
106
107// div* only work correctly for div > 0
121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 108// 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; } 109template<typename T> static inline T div (T val, T div)
110{
111 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
112}
123// div, round-up 113// div, round-up
124template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 114template<typename T> static inline T div_ru (T val, T div)
115{
116 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
117}
125// div, round-down 118// div, round-down
126template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 119template<typename T> static inline T div_rd (T val, T div)
120{
121 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
122}
127 123
124// lerp* only work correctly for min_in < max_in
125// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
128template<typename T> 126template<typename T>
129static inline T 127static inline T
130lerp (T val, T min_in, T max_in, T min_out, T max_out) 128lerp (T val, T min_in, T max_in, T min_out, T max_out)
131{ 129{
132 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 130 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
… …
191 int32_t d = b - a; 189 int32_t d = b - a;
192 d &= d >> 31; 190 d &= d >> 31;
193 return b - d; 191 return b - d;
194} 192}
195 193
196// this is much faster than crossfires original algorithm 194// this is much faster than crossfire's original algorithm
197// on modern cpus 195// on modern cpus
198inline int 196inline int
199isqrt (int n) 197isqrt (int n)
200{ 198{
201 return (int)sqrtf ((float)n); 199 return (int)sqrtf ((float)n);
200}
201
202// this is kind of like the ^^ operator, if it would exist, without sequence point.
203// more handy than it looks like, due to the implicit !! done on its arguments
204inline bool
205logical_xor (bool a, bool b)
206{
207 return a != b;
208}
209
210inline bool
211logical_implies (bool a, bool b)
212{
213 return a <= b;
202} 214}
203 215
204// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 216// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
205#if 0 217#if 0
206// and has a max. error of 6 in the range -100..+100. 218// and has a max. error of 6 in the range -100..+100.
… …
231absdir (int d) 243absdir (int d)
232{ 244{
233 return ((d - 1) & 7) + 1; 245 return ((d - 1) & 7) + 1;
234} 246}
235 247
248// avoid ctz name because netbsd or freebsd spams it's namespace with it
249#if GCC_VERSION(3,4)
250static inline int least_significant_bit (uint32_t x)
251{
252 return __builtin_ctz (x);
253}
254#else
255int least_significant_bit (uint32_t x);
256#endif
257
258#define for_all_bits_sparse_32(mask, idxvar) \
259 for (uint32_t idxvar, mask_ = mask; \
260 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
261
236extern ssize_t slice_alloc; // statistics 262extern ssize_t slice_alloc; // statistics
237 263
238void *salloc_ (int n) throw (std::bad_alloc); 264void *salloc_ (int n) throw (std::bad_alloc);
239void *salloc_ (int n, void *src) throw (std::bad_alloc); 265void *salloc_ (int n, void *src) throw (std::bad_alloc);
240 266
… …
407 433
408// Xorshift RNGs, George Marsaglia 434// Xorshift RNGs, George Marsaglia
409// http://www.jstatsoft.org/v08/i14/paper 435// http://www.jstatsoft.org/v08/i14/paper
410// this one is about 40% faster than the tausworthe one above (i.e. not much), 436// 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. 437// despite the inlining, and has the issue of only creating 2**32-1 numbers.
438// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
412struct xorshift_random_generator 439struct xorshift_random_generator
413{ 440{
414 uint32_t x, y; 441 uint32_t x, y;
415 442
416 void operator =(const xorshift_random_generator &src) 443 void operator =(const xorshift_random_generator &src)
… …
443 return !is_constant (num) ? get_range (num) // non-constant 470 return !is_constant (num) ? get_range (num) // non-constant
444 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 471 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
445 : this->next () & (num - 1); // constant, power-of-two 472 : this->next () & (num - 1); // constant, power-of-two
446 } 473 }
447 474
448 // return a number within (min .. max) 475 // return a number within the closed interval [min .. max]
449 int operator () (int r_min, int r_max) 476 int operator () (int r_min, int r_max)
450 { 477 {
451 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 478 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
452 ? r_min + operator ()(r_max - r_min + 1) 479 ? r_min + operator ()(r_max - r_min + 1)
453 : get_range (r_min, r_max); 480 : get_range (r_min, r_max);
454 } 481 }
455 482
483 // return a number within the closed interval [0..1]
456 double operator ()() 484 double operator ()()
457 { 485 {
458 return this->next () / (double)0xFFFFFFFFU; 486 return this->next () / (double)0xFFFFFFFFU;
459 } 487 }
460 488
… …
536typedef refptr<object> object_ptr; 564typedef refptr<object> object_ptr;
537typedef refptr<archetype> arch_ptr; 565typedef refptr<archetype> arch_ptr;
538typedef refptr<client> client_ptr; 566typedef refptr<client> client_ptr;
539typedef refptr<player> player_ptr; 567typedef refptr<player> player_ptr;
540 568
569#define STRHSH_NULL 2166136261
570
571static inline uint32_t
572strhsh (const char *s)
573{
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
575 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrently with the looping logic.
579 uint32_t hash = STRHSH_NULL;
580
581 while (*s)
582 hash = (hash ^ *s++) * 16777619U;
583
584 return hash;
585}
586
587static inline uint32_t
588memhsh (const char *s, size_t len)
589{
590 uint32_t hash = STRHSH_NULL;
591
592 while (len--)
593 hash = (hash ^ *s++) * 16777619U;
594
595 return hash;
596}
597
541struct str_hash 598struct str_hash
542{ 599{
543 std::size_t operator ()(const char *s) const 600 std::size_t operator ()(const char *s) const
544 { 601 {
545#if 0
546 uint32_t hash = 0;
547
548 /* use the one-at-a-time hash function, which supposedly is
549 * better than the djb2-like one used by perl5.005, but
550 * certainly is better then the bug used here before.
551 * see http://burtleburtle.net/bob/hash/doobs.html
552 */
553 while (*s)
554 {
555 hash += *s++;
556 hash += hash << 10;
557 hash ^= hash >> 6;
558 }
559
560 hash += hash << 3;
561 hash ^= hash >> 11;
562 hash += hash << 15;
563#else
564 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
565 // it is about twice as fast as the one-at-a-time one,
566 // with good distribution.
567 // FNV-1a is faster on many cpus because the multiplication
568 // runs concurrent with the looping logic.
569 uint32_t hash = 2166136261;
570
571 while (*s)
572 hash = (hash ^ *s++) * 16777619;
573#endif
574
575 return hash; 602 return strhsh (s);
603 }
604
605 std::size_t operator ()(const shstr &s) const
606 {
607 return strhsh (s);
576 } 608 }
577}; 609};
578 610
579struct str_equal 611struct str_equal
580{ 612{
… …
673 erase (&obj); 705 erase (&obj);
674 } 706 }
675}; 707};
676 708
677// basically does what strncpy should do, but appends "..." to strings exceeding length 709// basically does what strncpy should do, but appends "..." to strings exceeding length
710// returns the number of bytes actually used (including \0)
678void assign (char *dst, const char *src, int maxlen); 711int assign (char *dst, const char *src, int maxsize);
679 712
680// type-safe version of assign 713// type-safe version of assign
681template<int N> 714template<int N>
682inline void assign (char (&dst)[N], const char *src) 715inline int assign (char (&dst)[N], const char *src)
683{ 716{
684 assign ((char *)&dst, src, N); 717 return assign ((char *)&dst, src, N);
685} 718}
686 719
687typedef double tstamp; 720typedef double tstamp;
688 721
689// return current time as timestamp 722// return current time as timestamp
690tstamp now (); 723tstamp now ();
691 724
692int similar_direction (int a, int b); 725int similar_direction (int a, int b);
693 726
694// like sprintf, but returns a "static" buffer 727// like v?sprintf, but returns a "static" buffer
695const char *format (const char *format, ...); 728char *vformat (const char *format, va_list ap);
729char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
730
731// safety-check player input which will become object->msg
732bool msg_is_safe (const char *msg);
696 733
697///////////////////////////////////////////////////////////////////////////// 734/////////////////////////////////////////////////////////////////////////////
698// threads, very very thin wrappers around pthreads 735// threads, very very thin wrappers around pthreads
699 736
700struct thread 737struct thread

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