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Comparing deliantra/server/include/util.h (file contents):
Revision 1.80 by root, Tue Dec 23 01:51:28 2008 UTC vs.
Revision 1.95 by root, Tue Nov 10 00:01:31 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__
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>
… …
72#endif 55#endif
73 56
74// 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)
75#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
76 59
77// very ugly macro that basicaly declares and initialises a variable 60// very ugly macro that basically declares and initialises a variable
78// that is in scope for the next statement only 61// that is in scope for the next statement only
79// works only for stuff that can be assigned 0 and converts to false 62// works only for stuff that can be assigned 0 and converts to false
80// (note: works great for pointers) 63// (note: works great for pointers)
81// most ugly macro I ever wrote 64// most ugly macro I ever wrote
82#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 65#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
… …
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.
… …
389// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 398// 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 399// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
391// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps 400// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
392struct tausworthe_random_generator 401struct tausworthe_random_generator
393{ 402{
394 // generator
395 uint32_t state [4]; 403 uint32_t state [4];
396 404
397 void operator =(const tausworthe_random_generator &src) 405 void operator =(const tausworthe_random_generator &src)
398 { 406 {
399 state [0] = src.state [0]; 407 state [0] = src.state [0];
… …
402 state [3] = src.state [3]; 410 state [3] = src.state [3];
403 } 411 }
404 412
405 void seed (uint32_t seed); 413 void seed (uint32_t seed);
406 uint32_t next (); 414 uint32_t next ();
415};
407 416
417// Xorshift RNGs, George Marsaglia
418// http://www.jstatsoft.org/v08/i14/paper
419// this one is about 40% faster than the tausworthe one above (i.e. not much),
420// despite the inlining, and has the issue of only creating 2**32-1 numbers.
421// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
422struct xorshift_random_generator
423{
424 uint32_t x, y;
425
426 void operator =(const xorshift_random_generator &src)
427 {
428 x = src.x;
429 y = src.y;
430 }
431
432 void seed (uint32_t seed)
433 {
434 x = seed;
435 y = seed * 69069U;
436 }
437
438 uint32_t next ()
439 {
440 uint32_t t = x ^ (x << 10);
441 x = y;
442 y = y ^ (y >> 13) ^ t ^ (t >> 10);
443 return y;
444 }
445};
446
447template<class generator>
448struct random_number_generator : generator
449{
408 // uniform distribution, 0 .. max (0, num - 1) 450 // uniform distribution, 0 .. max (0, num - 1)
409 uint32_t operator ()(uint32_t num) 451 uint32_t operator ()(uint32_t num)
410 { 452 {
411 return is_constant (num) 453 return !is_constant (num) ? get_range (num) // non-constant
412 ? (next () * (uint64_t)num) >> 32U 454 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
413 : get_range (num); 455 : this->next () & (num - 1); // constant, power-of-two
414 } 456 }
415 457
416 // return a number within (min .. max) 458 // return a number within (min .. max)
417 int operator () (int r_min, int r_max) 459 int operator () (int r_min, int r_max)
418 { 460 {
… …
429protected: 471protected:
430 uint32_t get_range (uint32_t r_max); 472 uint32_t get_range (uint32_t r_max);
431 int get_range (int r_min, int r_max); 473 int get_range (int r_min, int r_max);
432}; 474};
433 475
434typedef tausworthe_random_generator rand_gen; 476typedef random_number_generator<tausworthe_random_generator> rand_gen;
435 477
436extern rand_gen rndm, rmg_rndm; 478extern rand_gen rndm, rmg_rndm;
437 479
438INTERFACE_CLASS (attachable) 480INTERFACE_CLASS (attachable)
439struct refcnt_base 481struct refcnt_base
… …
504typedef refptr<object> object_ptr; 546typedef refptr<object> object_ptr;
505typedef refptr<archetype> arch_ptr; 547typedef refptr<archetype> arch_ptr;
506typedef refptr<client> client_ptr; 548typedef refptr<client> client_ptr;
507typedef refptr<player> player_ptr; 549typedef refptr<player> player_ptr;
508 550
551#define STRHSH_NULL 2166136261
552
553static inline uint32_t
554strhsh (const char *s)
555{
556 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
557 // it is about twice as fast as the one-at-a-time one,
558 // with good distribution.
559 // FNV-1a is faster on many cpus because the multiplication
560 // runs concurrently with the looping logic.
561 uint32_t hash = STRHSH_NULL;
562
563 while (*s)
564 hash = (hash ^ *s++) * 16777619;
565
566 return hash;
567}
568
569static inline uint32_t
570memhsh (const char *s, size_t len)
571{
572 uint32_t hash = STRHSH_NULL;
573
574 while (len--)
575 hash = (hash ^ *s++) * 16777619;
576
577 return hash;
578}
579
509struct str_hash 580struct str_hash
510{ 581{
511 std::size_t operator ()(const char *s) const 582 std::size_t operator ()(const char *s) const
512 { 583 {
513 unsigned long hash = 0;
514
515 /* use the one-at-a-time hash function, which supposedly is
516 * better than the djb2-like one used by perl5.005, but
517 * certainly is better then the bug used here before.
518 * see http://burtleburtle.net/bob/hash/doobs.html
519 */
520 while (*s)
521 {
522 hash += *s++;
523 hash += hash << 10;
524 hash ^= hash >> 6;
525 }
526
527 hash += hash << 3;
528 hash ^= hash >> 11;
529 hash += hash << 15;
530
531 return hash; 584 return strhsh (s);
585 }
586
587 std::size_t operator ()(const shstr &s) const
588 {
589 return strhsh (s);
532 } 590 }
533}; 591};
534 592
535struct str_equal 593struct str_equal
536{ 594{
… …
629 erase (&obj); 687 erase (&obj);
630 } 688 }
631}; 689};
632 690
633// basically does what strncpy should do, but appends "..." to strings exceeding length 691// basically does what strncpy should do, but appends "..." to strings exceeding length
692// returns the number of bytes actually used (including \0)
634void assign (char *dst, const char *src, int maxlen); 693int assign (char *dst, const char *src, int maxsize);
635 694
636// type-safe version of assign 695// type-safe version of assign
637template<int N> 696template<int N>
638inline void assign (char (&dst)[N], const char *src) 697inline int assign (char (&dst)[N], const char *src)
639{ 698{
640 assign ((char *)&dst, src, N); 699 return assign ((char *)&dst, src, N);
641} 700}
642 701
643typedef double tstamp; 702typedef double tstamp;
644 703
645// return current time as timestamp 704// return current time as timestamp
646tstamp now (); 705tstamp now ();
647 706
648int similar_direction (int a, int b); 707int similar_direction (int a, int b);
649 708
650// like sprintf, but returns a "static" buffer 709// like v?sprintf, but returns a "static" buffer
651const char *format (const char *format, ...); 710char *vformat (const char *format, va_list ap);
711char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
712
713// safety-check player input which will become object->msg
714bool msg_is_safe (const char *msg);
652 715
653///////////////////////////////////////////////////////////////////////////// 716/////////////////////////////////////////////////////////////////////////////
654// threads, very very thin wrappers around pthreads 717// threads, very very thin wrappers around pthreads
655 718
656struct thread 719struct thread

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