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Comparing deliantra/server/include/util.h (file contents):
Revision 1.90 by root, Mon Oct 12 14:00:58 2009 UTC vs.
Revision 1.101 by root, Wed Apr 28 19:49:50 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// could use the sizeof (arr) /( sizeof (arr [0]) here, but C++ is
61// much more obfuscated... :)
62
63template<typename T, int N>
64inline int array_length (const T (&arr)[N])
65{
66 return N;
67}
68
80// very ugly macro that basically declares and initialises a variable 69// very ugly macro that basically declares and initialises a variable
81// that is in scope for the next statement only 70// that is in scope for the next statement only
82// works only for stuff that can be assigned 0 and converts to false 71// works only for stuff that can be assigned 0 and converts to false
83// (note: works great for pointers) 72// (note: works great for pointers)
84// most ugly macro I ever wrote 73// most ugly macro I ever wrote
119 108
120// sign0 returns -1, 0 or +1 109// sign0 returns -1, 0 or +1
121template<typename T> 110template<typename T>
122static inline T sign0 (T v) { return v ? sign (v) : 0; } 111static inline T sign0 (T v) { return v ? sign (v) : 0; }
123 112
113template<typename T, typename U>
114static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
115
124// div* only work correctly for div > 0 116// div* only work correctly for div > 0
125// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 117// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
126template<typename T> static inline T div (T val, T div) 118template<typename T> static inline T div (T val, T div)
127{ 119{
128 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 120 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
206 int32_t d = b - a; 198 int32_t d = b - a;
207 d &= d >> 31; 199 d &= d >> 31;
208 return b - d; 200 return b - d;
209} 201}
210 202
211// this is much faster than crossfires original algorithm 203// this is much faster than crossfire's original algorithm
212// on modern cpus 204// on modern cpus
213inline int 205inline int
214isqrt (int n) 206isqrt (int n)
215{ 207{
216 return (int)sqrtf ((float)n); 208 return (int)sqrtf ((float)n);
209}
210
211// this is kind of like the ^^ operator, if it would exist, without sequence point.
212// more handy than it looks like, due to the implicit !! done on its arguments
213inline bool
214logical_xor (bool a, bool b)
215{
216 return a != b;
217}
218
219inline bool
220logical_implies (bool a, bool b)
221{
222 return a <= b;
217} 223}
218 224
219// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 225// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
220#if 0 226#if 0
221// and has a max. error of 6 in the range -100..+100. 227// and has a max. error of 6 in the range -100..+100.
246absdir (int d) 252absdir (int d)
247{ 253{
248 return ((d - 1) & 7) + 1; 254 return ((d - 1) & 7) + 1;
249} 255}
250 256
257// avoid ctz name because netbsd or freebsd spams it's namespace with it
258#if GCC_VERSION(3,4)
259static inline int least_significant_bit (uint32_t x)
260{
261 return __builtin_ctz (x);
262}
263#else
264int least_significant_bit (uint32_t x);
265#endif
266
267#define for_all_bits_sparse_32(mask, idxvar) \
268 for (uint32_t idxvar, mask_ = mask; \
269 mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);)
270
251extern ssize_t slice_alloc; // statistics 271extern ssize_t slice_alloc; // statistics
252 272
253void *salloc_ (int n) throw (std::bad_alloc); 273void *salloc_ (int n) throw (std::bad_alloc);
254void *salloc_ (int n, void *src) throw (std::bad_alloc); 274void *salloc_ (int n, void *src) throw (std::bad_alloc);
255 275
459 return !is_constant (num) ? get_range (num) // non-constant 479 return !is_constant (num) ? get_range (num) // non-constant
460 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 480 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
461 : this->next () & (num - 1); // constant, power-of-two 481 : this->next () & (num - 1); // constant, power-of-two
462 } 482 }
463 483
464 // return a number within (min .. max) 484 // return a number within the closed interval [min .. max]
465 int operator () (int r_min, int r_max) 485 int operator () (int r_min, int r_max)
466 { 486 {
467 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 487 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
468 ? r_min + operator ()(r_max - r_min + 1) 488 ? r_min + operator ()(r_max - r_min + 1)
469 : get_range (r_min, r_max); 489 : get_range (r_min, r_max);
470 } 490 }
471 491
492 // return a number within the closed interval [0..1]
472 double operator ()() 493 double operator ()()
473 { 494 {
474 return this->next () / (double)0xFFFFFFFFU; 495 return this->next () / (double)0xFFFFFFFFU;
475 } 496 }
476 497
552typedef refptr<object> object_ptr; 573typedef refptr<object> object_ptr;
553typedef refptr<archetype> arch_ptr; 574typedef refptr<archetype> arch_ptr;
554typedef refptr<client> client_ptr; 575typedef refptr<client> client_ptr;
555typedef refptr<player> player_ptr; 576typedef refptr<player> player_ptr;
556 577
578#define STRHSH_NULL 2166136261
579
580static inline uint32_t
581strhsh (const char *s)
582{
583 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
584 // it is about twice as fast as the one-at-a-time one,
585 // with good distribution.
586 // FNV-1a is faster on many cpus because the multiplication
587 // runs concurrently with the looping logic.
588 uint32_t hash = STRHSH_NULL;
589
590 while (*s)
591 hash = (hash ^ *s++) * 16777619U;
592
593 return hash;
594}
595
596static inline uint32_t
597memhsh (const char *s, size_t len)
598{
599 uint32_t hash = STRHSH_NULL;
600
601 while (len--)
602 hash = (hash ^ *s++) * 16777619U;
603
604 return hash;
605}
606
557struct str_hash 607struct str_hash
558{ 608{
559 std::size_t operator ()(const char *s) const 609 std::size_t operator ()(const char *s) const
560 { 610 {
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; 611 return strhsh (s);
612 }
613
614 std::size_t operator ()(const shstr &s) const
615 {
616 return strhsh (s);
592 } 617 }
593}; 618};
594 619
595struct str_equal 620struct str_equal
596{ 621{
706// return current time as timestamp 731// return current time as timestamp
707tstamp now (); 732tstamp now ();
708 733
709int similar_direction (int a, int b); 734int similar_direction (int a, int b);
710 735
711// like sprintf, but returns a "static" buffer 736// like v?sprintf, but returns a "static" buffer
712const char *format (const char *format, ...); 737char *vformat (const char *format, va_list ap);
738char *format (const char *format, ...) attribute ((format (printf, 1, 2)));
713 739
714// safety-check player input which will become object->msg 740// safety-check player input which will become object->msg
715bool msg_is_safe (const char *msg); 741bool msg_is_safe (const char *msg);
716 742
717///////////////////////////////////////////////////////////////////////////// 743/////////////////////////////////////////////////////////////////////////////

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