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 1.84 by root, Wed Dec 31 17:35:37 2008 UTC vs.
Revision 1.108 by root, Wed May 26 19:11:43 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>
… …
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
60#if cplusplus_does_not_suck
61// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
62template<typename T, int N>
63static inline int array_length (const T (&arr)[N])
64{
65 return N;
66}
67#else
68#define array_length(name) (sizeof (name) / sizeof (name [0]))
69#endif
70
77// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
78// that is in scope for the next statement only 72// that is in scope for the next statement only
79// works only for stuff that can be assigned 0 and converts to false 73// works only for stuff that can be assigned 0 and converts to false
80// (note: works great for pointers) 74// (note: works great for pointers)
81// most ugly macro I ever wrote 75// most ugly macro I ever wrote
… …
110// sign returns -1 or +1 104// sign returns -1 or +1
111template<typename T> 105template<typename T>
112static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
113// relies on 2c representation 107// relies on 2c representation
114template<> 108template<>
115inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } 109inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
110template<>
111inline sint16 sign (sint16 v) { return 1 - (sint16 (uint16 (v) >> 15) * 2); }
112template<>
113inline sint32 sign (sint32 v) { return 1 - (sint32 (uint32 (v) >> 31) * 2); }
116 114
117// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
118template<typename T> 116template<typename T>
119static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
120 118
119template<typename T, typename U>
120static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
121
122// div* only work correctly for div > 0
121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// 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; } 124template<typename T> static inline T div (T val, T div)
125{
126 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
127}
128
129template<> inline float div (float val, float div) { return val / div; }
130template<> inline double div (double val, double div) { return val / div; }
131
123// div, round-up 132// div, round-up
124template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 133template<typename T> static inline T div_ru (T val, T div)
134{
135 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
136}
125// div, round-down 137// div, round-down
126template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 138template<typename T> static inline T div_rd (T val, T div)
139{
140 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
141}
127 142
143// lerp* only work correctly for min_in < max_in
144// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
128template<typename T> 145template<typename T>
129static inline T 146static inline T
130lerp (T val, T min_in, T max_in, T min_out, T max_out) 147lerp (T val, T min_in, T max_in, T min_out, T max_out)
131{ 148{
132 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 149 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
… …
191 int32_t d = b - a; 208 int32_t d = b - a;
192 d &= d >> 31; 209 d &= d >> 31;
193 return b - d; 210 return b - d;
194} 211}
195 212
196// this is much faster than crossfires original algorithm 213// this is much faster than crossfire's original algorithm
197// on modern cpus 214// on modern cpus
198inline int 215inline int
199isqrt (int n) 216isqrt (int n)
200{ 217{
201 return (int)sqrtf ((float)n); 218 return (int)sqrtf ((float)n);
219}
220
221// this is kind of like the ^^ operator, if it would exist, without sequence point.
222// more handy than it looks like, due to the implicit !! done on its arguments
223inline bool
224logical_xor (bool a, bool b)
225{
226 return a != b;
227}
228
229inline bool
230logical_implies (bool a, bool b)
231{
232 return a <= b;
202} 233}
203 234
204// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 235// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
205#if 0 236#if 0
206// and has a max. error of 6 in the range -100..+100. 237// and has a max. error of 6 in the range -100..+100.
… …
231absdir (int d) 262absdir (int d)
232{ 263{
233 return ((d - 1) & 7) + 1; 264 return ((d - 1) & 7) + 1;
234} 265}
235 266
267// avoid ctz name because netbsd or freebsd spams it's namespace with it
268#if GCC_VERSION(3,4)
269static inline int least_significant_bit (uint32_t x)
270{
271 return __builtin_ctz (x);
272}
273#else
274int least_significant_bit (uint32_t x);
275#endif
276
277#define for_all_bits_sparse_32(mask, idxvar) \
278 for (uint32_t idxvar, mask_ = mask; \
279 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
280
236extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
237 282
238void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n) throw (std::bad_alloc);
239void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src) throw (std::bad_alloc);
240 285
… …
407 452
408// Xorshift RNGs, George Marsaglia 453// Xorshift RNGs, George Marsaglia
409// http://www.jstatsoft.org/v08/i14/paper 454// http://www.jstatsoft.org/v08/i14/paper
410// this one is about 40% faster than the tausworthe one above (i.e. not much), 455// 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. 456// despite the inlining, and has the issue of only creating 2**32-1 numbers.
457// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
412struct xorshift_random_generator 458struct xorshift_random_generator
413{ 459{
414 uint32_t x, y; 460 uint32_t x, y;
415 461
416 void operator =(const xorshift_random_generator &src) 462 void operator =(const xorshift_random_generator &src)
… …
435}; 481};
436 482
437template<class generator> 483template<class generator>
438struct random_number_generator : generator 484struct random_number_generator : generator
439{ 485{
440 // uniform distribution, 0 .. max (0, num - 1) 486 // uniform distribution, [0 .. num - 1]
441 uint32_t operator ()(uint32_t num) 487 uint32_t operator ()(uint32_t num)
442 { 488 {
443 return !is_constant (num) ? get_range (num) // non-constant 489 return !is_constant (num) ? get_range (num) // non-constant
444 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 490 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
445 : this->next () & (num - 1); // constant, power-of-two 491 : this->next () & (num - 1); // constant, power-of-two
446 } 492 }
447 493
448 // return a number within (min .. max) 494 // return a number within the closed interval [min .. max]
449 int operator () (int r_min, int r_max) 495 int operator () (int r_min, int r_max)
450 { 496 {
451 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 497 return is_constant (r_min <= r_max) && r_min <= r_max
452 ? r_min + operator ()(r_max - r_min + 1) 498 ? r_min + operator ()(r_max - r_min + 1)
453 : get_range (r_min, r_max); 499 : get_range (r_min, r_max);
454 } 500 }
455 501
502 // return a number within the half-open interval [0..1[
456 double operator ()() 503 double operator ()()
457 { 504 {
458 return this->next () / (double)0xFFFFFFFFU; 505 return this->next () / (double)0x100000000ULL;
459 } 506 }
460 507
461protected: 508protected:
462 uint32_t get_range (uint32_t r_max); 509 uint32_t get_range (uint32_t r_max);
463 int get_range (int r_min, int r_max); 510 int get_range (int r_min, int r_max);
… …
535typedef refptr<maptile> maptile_ptr; 582typedef refptr<maptile> maptile_ptr;
536typedef refptr<object> object_ptr; 583typedef refptr<object> object_ptr;
537typedef refptr<archetype> arch_ptr; 584typedef refptr<archetype> arch_ptr;
538typedef refptr<client> client_ptr; 585typedef refptr<client> client_ptr;
539typedef refptr<player> player_ptr; 586typedef refptr<player> player_ptr;
587typedef refptr<region> region_ptr;
588
589#define STRHSH_NULL 2166136261
590
591static inline uint32_t
592strhsh (const char *s)
593{
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 concurrently with the looping logic.
599 uint32_t hash = STRHSH_NULL;
600
601 while (*s)
602 hash = (hash ^ *s++) * 16777619U;
603
604 return hash;
605}
606
607static inline uint32_t
608memhsh (const char *s, size_t len)
609{
610 uint32_t hash = STRHSH_NULL;
611
612 while (len--)
613 hash = (hash ^ *s++) * 16777619U;
614
615 return hash;
616}
540 617
541struct str_hash 618struct str_hash
542{ 619{
543 std::size_t operator ()(const char *s) const 620 std::size_t operator ()(const char *s) const
544 { 621 {
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; 622 return strhsh (s);
623 }
624
625 std::size_t operator ()(const shstr &s) const
626 {
627 return strhsh (s);
576 } 628 }
577}; 629};
578 630
579struct str_equal 631struct str_equal
580{ 632{
… …
673 erase (&obj); 725 erase (&obj);
674 } 726 }
675}; 727};
676 728
677// basically does what strncpy should do, but appends "..." to strings exceeding length 729// basically does what strncpy should do, but appends "..." to strings exceeding length
730// returns the number of bytes actually used (including \0)
678void assign (char *dst, const char *src, int maxlen); 731int assign (char *dst, const char *src, int maxsize);
679 732
680// type-safe version of assign 733// type-safe version of assign
681template<int N> 734template<int N>
682inline void assign (char (&dst)[N], const char *src) 735inline int assign (char (&dst)[N], const char *src)
683{ 736{
684 assign ((char *)&dst, src, N); 737 return assign ((char *)&dst, src, N);
685} 738}
686 739
687typedef double tstamp; 740typedef double tstamp;
688 741
689// return current time as timestamp 742// return current time as timestamp
690tstamp now (); 743tstamp now ();
691 744
692int similar_direction (int a, int b); 745int similar_direction (int a, int b);
693 746
694// like sprintf, but returns a "static" buffer 747// like v?sprintf, but returns a "static" buffer
695const char *format (const char *format, ...); 748char *vformat (const char *format, va_list ap);
749char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
750
751// safety-check player input which will become object->msg
752bool msg_is_safe (const char *msg);
696 753
697///////////////////////////////////////////////////////////////////////////// 754/////////////////////////////////////////////////////////////////////////////
698// threads, very very thin wrappers around pthreads 755// threads, very very thin wrappers around pthreads
699 756
700struct thread 757struct thread

Diff Legend

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