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Comparing deliantra/server/include/util.h (file contents):
Revision 1.87 by root, Mon Jan 12 03:40:21 2009 UTC vs.
Revision 1.107 by root, Sun May 2 14:46:56 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# define noinline __attribute__((__noinline__))
34#else
35# define is_constant(c) 0
36# define expect(expr,value) (expr)
37# define prefetch(addr,rw,locality)
38# define noinline
39#endif
40
41#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
42# define decltype(x) typeof(x)
43#endif
44
45// put into ifs if you are very sure that the expression
46// is mostly true or mosty false. note that these return
47// booleans, not the expression.
48#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
49#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
50 31
51#include <pthread.h> 32#include <pthread.h>
52 33
53#include <cstddef> 34#include <cstddef>
54#include <cmath> 35#include <cmath>
… …
74#endif 55#endif
75 56
76// 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)
77#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
78 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
79// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
80// that is in scope for the next statement only 72// that is in scope for the next statement only
81// 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
82// (note: works great for pointers) 74// (note: works great for pointers)
83// most ugly macro I ever wrote 75// most ugly macro I ever wrote
… …
112// sign returns -1 or +1 104// sign returns -1 or +1
113template<typename T> 105template<typename T>
114static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
115// relies on 2c representation 107// relies on 2c representation
116template<> 108template<>
117inline 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); }
118 114
119// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
120template<typename T> 116template<typename T>
121static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
122 118
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
123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
124template<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
125// div, round-up 132// div, round-up
126template<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}
127// div, round-down 137// div, round-down
128template<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}
129 142
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
130template<typename T> 145template<typename T>
131static inline T 146static inline T
132lerp (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)
133{ 148{
134 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);
… …
193 int32_t d = b - a; 208 int32_t d = b - a;
194 d &= d >> 31; 209 d &= d >> 31;
195 return b - d; 210 return b - d;
196} 211}
197 212
198// this is much faster than crossfires original algorithm 213// this is much faster than crossfire's original algorithm
199// on modern cpus 214// on modern cpus
200inline int 215inline int
201isqrt (int n) 216isqrt (int n)
202{ 217{
203 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;
204} 233}
205 234
206// 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)
207#if 0 236#if 0
208// 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.
… …
233absdir (int d) 262absdir (int d)
234{ 263{
235 return ((d - 1) & 7) + 1; 264 return ((d - 1) & 7) + 1;
236} 265}
237 266
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
238extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
239 282
240void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n) throw (std::bad_alloc);
241void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src) throw (std::bad_alloc);
242 285
… …
438}; 481};
439 482
440template<class generator> 483template<class generator>
441struct random_number_generator : generator 484struct random_number_generator : generator
442{ 485{
443 // uniform distribution, 0 .. max (0, num - 1) 486 // uniform distribution, [0 .. num - 1]
444 uint32_t operator ()(uint32_t num) 487 uint32_t operator ()(uint32_t num)
445 { 488 {
446 return !is_constant (num) ? get_range (num) // non-constant 489 return !is_constant (num) ? get_range (num) // non-constant
447 : 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
448 : this->next () & (num - 1); // constant, power-of-two 491 : this->next () & (num - 1); // constant, power-of-two
449 } 492 }
450 493
451 // return a number within (min .. max) 494 // return a number within the closed interval [min .. max]
452 int operator () (int r_min, int r_max) 495 int operator () (int r_min, int r_max)
453 { 496 {
454 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
455 ? r_min + operator ()(r_max - r_min + 1) 498 ? r_min + operator ()(r_max - r_min + 1)
456 : get_range (r_min, r_max); 499 : get_range (r_min, r_max);
457 } 500 }
458 501
502 // return a number within the half-open interval [0..1[
459 double operator ()() 503 double operator ()()
460 { 504 {
461 return this->next () / (double)0xFFFFFFFFU; 505 return this->next () / (double)0x100000000;
462 } 506 }
463 507
464protected: 508protected:
465 uint32_t get_range (uint32_t r_max); 509 uint32_t get_range (uint32_t r_max);
466 int get_range (int r_min, int r_max); 510 int get_range (int r_min, int r_max);
… …
538typedef refptr<maptile> maptile_ptr; 582typedef refptr<maptile> maptile_ptr;
539typedef refptr<object> object_ptr; 583typedef refptr<object> object_ptr;
540typedef refptr<archetype> arch_ptr; 584typedef refptr<archetype> arch_ptr;
541typedef refptr<client> client_ptr; 585typedef refptr<client> client_ptr;
542typedef 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}
543 617
544struct str_hash 618struct str_hash
545{ 619{
546 std::size_t operator ()(const char *s) const 620 std::size_t operator ()(const char *s) const
547 { 621 {
548#if 0
549 uint32_t hash = 0;
550
551 /* use the one-at-a-time hash function, which supposedly is
552 * better than the djb2-like one used by perl5.005, but
553 * certainly is better then the bug used here before.
554 * see http://burtleburtle.net/bob/hash/doobs.html
555 */
556 while (*s)
557 {
558 hash += *s++;
559 hash += hash << 10;
560 hash ^= hash >> 6;
561 }
562
563 hash += hash << 3;
564 hash ^= hash >> 11;
565 hash += hash << 15;
566#else
567 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
568 // it is about twice as fast as the one-at-a-time one,
569 // with good distribution.
570 // FNV-1a is faster on many cpus because the multiplication
571 // runs concurrent with the looping logic.
572 uint32_t hash = 2166136261;
573
574 while (*s)
575 hash = (hash ^ *s++) * 16777619;
576#endif
577
578 return hash; 622 return strhsh (s);
623 }
624
625 std::size_t operator ()(const shstr &s) const
626 {
627 return strhsh (s);
579 } 628 }
580}; 629};
581 630
582struct str_equal 631struct str_equal
583{ 632{
… …
693// return current time as timestamp 742// return current time as timestamp
694tstamp now (); 743tstamp now ();
695 744
696int similar_direction (int a, int b); 745int similar_direction (int a, int b);
697 746
698// like sprintf, but returns a "static" buffer 747// like v?sprintf, but returns a "static" buffer
699const 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);
700 753
701///////////////////////////////////////////////////////////////////////////// 754/////////////////////////////////////////////////////////////////////////////
702// threads, very very thin wrappers around pthreads 755// threads, very very thin wrappers around pthreads
703 756
704struct thread 757struct thread

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