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 1.90 by root, Mon Oct 12 14:00:58 2009 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 it under 6 * Deliantra is free software: you can redistribute it and/or modify it under
7 * the terms of the Affero GNU General Public License as published by the 7 * the terms of the Affero GNU General Public License as published by the
8 * Free Software Foundation, either version 3 of the License, or (at your 8 * Free Software Foundation, either version 3 of the License, or (at your
9 * option) any later version. 9 * option) any later version.
… …
21 */ 21 */
22 22
23#ifndef UTIL_H__ 23#ifndef UTIL_H__
24#define UTIL_H__ 24#define UTIL_H__
25 25
26#include <compiler.h>
27
26#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0 28#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
27#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs 29#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
28#define PREFER_MALLOC 0 // use malloc and not the slice allocator 30#define PREFER_MALLOC 0 // use malloc and not the slice allocator
29
30#if __GNUC__ >= 3
31# define is_constant(c) __builtin_constant_p (c)
32# define expect(expr,value) __builtin_expect ((expr),(value))
33# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
34# define noinline __attribute__((__noinline__))
35#else
36# define is_constant(c) 0
37# define expect(expr,value) (expr)
38# define prefetch(addr,rw,locality)
39# define noinline
40#endif
41
42#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
43# define decltype(x) typeof(x)
44#endif
45
46// put into ifs if you are very sure that the expression
47// is mostly true or mosty false. note that these return
48// booleans, not the expression.
49#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
50#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
51 31
52#include <pthread.h> 32#include <pthread.h>
53 33
54#include <cstddef> 34#include <cstddef>
55#include <cmath> 35#include <cmath>
… …
75#endif 55#endif
76 56
77// 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)
78#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
79 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
80// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
81// that is in scope for the next statement only 72// that is in scope for the next statement only
82// 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
83// (note: works great for pointers) 74// (note: works great for pointers)
84// most ugly macro I ever wrote 75// most ugly macro I ever wrote
… …
113// sign returns -1 or +1 104// sign returns -1 or +1
114template<typename T> 105template<typename T>
115static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
116// relies on 2c representation 107// relies on 2c representation
117template<> 108template<>
118inline 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); }
119 114
120// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
121template<typename T> 116template<typename T>
122static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
118
119template<typename T, typename U>
120static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
123 121
124// div* only work correctly for div > 0 122// div* only work correctly for div > 0
125// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
126template<typename T> static inline T div (T val, T div) 124template<typename T> static inline T div (T val, T div)
127{ 125{
128 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 126 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
129} 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
130// div, round-up 132// div, round-up
131template<typename T> static inline T div_ru (T val, T div) 133template<typename T> static inline T div_ru (T val, T div)
132{ 134{
133 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 135 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
134} 136}
… …
206 int32_t d = b - a; 208 int32_t d = b - a;
207 d &= d >> 31; 209 d &= d >> 31;
208 return b - d; 210 return b - d;
209} 211}
210 212
211// this is much faster than crossfires original algorithm 213// this is much faster than crossfire's original algorithm
212// on modern cpus 214// on modern cpus
213inline int 215inline int
214isqrt (int n) 216isqrt (int n)
215{ 217{
216 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;
217} 233}
218 234
219// 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)
220#if 0 236#if 0
221// 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.
… …
246absdir (int d) 262absdir (int d)
247{ 263{
248 return ((d - 1) & 7) + 1; 264 return ((d - 1) & 7) + 1;
249} 265}
250 266
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
251extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
252 282
253void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n) throw (std::bad_alloc);
254void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src) throw (std::bad_alloc);
255 285
… …
451}; 481};
452 482
453template<class generator> 483template<class generator>
454struct random_number_generator : generator 484struct random_number_generator : generator
455{ 485{
456 // uniform distribution, 0 .. max (0, num - 1) 486 // uniform distribution, [0 .. num - 1]
457 uint32_t operator ()(uint32_t num) 487 uint32_t operator ()(uint32_t num)
458 { 488 {
459 return !is_constant (num) ? get_range (num) // non-constant 489 return !is_constant (num) ? get_range (num) // non-constant
460 : 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
461 : this->next () & (num - 1); // constant, power-of-two 491 : this->next () & (num - 1); // constant, power-of-two
462 } 492 }
463 493
464 // return a number within (min .. max) 494 // return a number within the closed interval [min .. max]
465 int operator () (int r_min, int r_max) 495 int operator () (int r_min, int r_max)
466 { 496 {
467 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
468 ? r_min + operator ()(r_max - r_min + 1) 498 ? r_min + operator ()(r_max - r_min + 1)
469 : get_range (r_min, r_max); 499 : get_range (r_min, r_max);
470 } 500 }
471 501
502 // return a number within the half-open interval [0..1[
472 double operator ()() 503 double operator ()()
473 { 504 {
474 return this->next () / (double)0xFFFFFFFFU; 505 return this->next () / (double)0x100000000ULL;
475 } 506 }
476 507
477protected: 508protected:
478 uint32_t get_range (uint32_t r_max); 509 uint32_t get_range (uint32_t r_max);
479 int get_range (int r_min, int r_max); 510 int get_range (int r_min, int r_max);
… …
551typedef refptr<maptile> maptile_ptr; 582typedef refptr<maptile> maptile_ptr;
552typedef refptr<object> object_ptr; 583typedef refptr<object> object_ptr;
553typedef refptr<archetype> arch_ptr; 584typedef refptr<archetype> arch_ptr;
554typedef refptr<client> client_ptr; 585typedef refptr<client> client_ptr;
555typedef 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}
556 617
557struct str_hash 618struct str_hash
558{ 619{
559 std::size_t operator ()(const char *s) const 620 std::size_t operator ()(const char *s) const
560 { 621 {
561#if 0
562 uint32_t hash = 0;
563
564 /* use the one-at-a-time hash function, which supposedly is
565 * better than the djb2-like one used by perl5.005, but
566 * certainly is better then the bug used here before.
567 * see http://burtleburtle.net/bob/hash/doobs.html
568 */
569 while (*s)
570 {
571 hash += *s++;
572 hash += hash << 10;
573 hash ^= hash >> 6;
574 }
575
576 hash += hash << 3;
577 hash ^= hash >> 11;
578 hash += hash << 15;
579#else
580 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
581 // it is about twice as fast as the one-at-a-time one,
582 // with good distribution.
583 // FNV-1a is faster on many cpus because the multiplication
584 // runs concurrent with the looping logic.
585 uint32_t hash = 2166136261;
586
587 while (*s)
588 hash = (hash ^ *s++) * 16777619;
589#endif
590
591 return hash; 622 return strhsh (s);
623 }
624
625 std::size_t operator ()(const shstr &s) const
626 {
627 return strhsh (s);
592 } 628 }
593}; 629};
594 630
595struct str_equal 631struct str_equal
596{ 632{
… …
706// return current time as timestamp 742// return current time as timestamp
707tstamp now (); 743tstamp now ();
708 744
709int similar_direction (int a, int b); 745int similar_direction (int a, int b);
710 746
711// like sprintf, but returns a "static" buffer 747// like v?sprintf, but returns a "static" buffer
712const char *format (const char *format, ...); 748char *vformat (const char *format, va_list ap);
749char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
713 750
714// safety-check player input which will become object->msg 751// safety-check player input which will become object->msg
715bool msg_is_safe (const char *msg); 752bool msg_is_safe (const char *msg);
716 753
717///////////////////////////////////////////////////////////////////////////// 754/////////////////////////////////////////////////////////////////////////////

Diff Legend

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