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Comparing deliantra/server/include/util.h (file contents):
Revision 1.31 by root, Mon Jan 15 02:39:41 2007 UTC vs.
Revision 1.49 by root, Mon Jun 4 13:04:00 2007 UTC

1/*
2 * This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
3 *
4 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
5 *
6 * Crossfire TRT is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
18 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * The authors can be reached via e-mail to <crossfire@schmorp.de>
21 */
22
1#ifndef UTIL_H__ 23#ifndef UTIL_H__
2#define UTIL_H__ 24#define UTIL_H__
3 25
26//#define PREFER_MALLOC
27
4#if __GNUC__ >= 3 28#if __GNUC__ >= 3
5# define is_constant(c) __builtin_constant_p (c) 29# define is_constant(c) __builtin_constant_p (c)
30# define expect(expr,value) __builtin_expect ((expr),(value))
31# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
6#else 32#else
7# define is_constant(c) 0 33# define is_constant(c) 0
34# define expect(expr,value) (expr)
35# define prefetch(addr,rw,locality)
8#endif 36#endif
37
38#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
39# define decltype(x) typeof(x)
40#endif
41
42// put into ifs if you are very sure that the expression
43// is mostly true or mosty false. note that these return
44// booleans, not the expression.
45#define expect_false(expr) expect ((expr) != 0, 0)
46#define expect_true(expr) expect ((expr) != 0, 1)
9 47
10#include <cstddef> 48#include <cstddef>
11#include <cmath> 49#include <cmath>
12#include <new> 50#include <new>
13#include <vector> 51#include <vector>
… …
15#include <glib.h> 53#include <glib.h>
16 54
17#include <shstr.h> 55#include <shstr.h>
18#include <traits.h> 56#include <traits.h>
19 57
20// use a gcc extension for auto declarations until ISO C++ sanctifies them 58// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
21#define AUTODECL(var,expr) typeof(expr) var = (expr) 59#define auto(var,expr) decltype(expr) var = (expr)
22 60
23// very ugly macro that basicaly declares and initialises a variable 61// very ugly macro that basicaly declares and initialises a variable
24// that is in scope for the next statement only 62// that is in scope for the next statement only
25// works only for stuff that can be assigned 0 and converts to false 63// works only for stuff that can be assigned 0 and converts to false
26// (note: works great for pointers) 64// (note: works great for pointers)
27// most ugly macro I ever wrote 65// most ugly macro I ever wrote
28#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 66#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
29 67
30// in range including end 68// in range including end
31#define IN_RANGE_INC(val,beg,end) \ 69#define IN_RANGE_INC(val,beg,end) \
32 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg)) 70 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
33 71
34// in range excluding end 72// in range excluding end
35#define IN_RANGE_EXC(val,beg,end) \ 73#define IN_RANGE_EXC(val,beg,end) \
36 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg)) 74 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
37 75
38void fork_abort (const char *msg); 76void fork_abort (const char *msg);
77
78// rationale for using (U) not (T) is to reduce signed/unsigned issues,
79// as a is often a constant while b is the variable. it is still a bug, though.
80template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
81template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
82template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }
83
84template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
85
86template<typename T>
87static inline T
88lerp (T val, T min_in, T max_in, T min_out, T max_out)
89{
90 return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
91}
92
93// lots of stuff taken from FXT
94
95/* Rotate right. This is used in various places for checksumming */
96//TODO: that sucks, use a better checksum algo
97static inline uint32_t
98rotate_right (uint32_t c, uint32_t count = 1)
99{
100 return (c << (32 - count)) | (c >> count);
101}
102
103static inline uint32_t
104rotate_left (uint32_t c, uint32_t count = 1)
105{
106 return (c >> (32 - count)) | (c << count);
107}
108
109// Return abs(a-b)
110// Both a and b must not have the most significant bit set
111static inline uint32_t
112upos_abs_diff (uint32_t a, uint32_t b)
113{
114 long d1 = b - a;
115 long d2 = (d1 & (d1 >> 31)) << 1;
116
117 return d1 - d2; // == (b - d) - (a + d);
118}
119
120// Both a and b must not have the most significant bit set
121static inline uint32_t
122upos_min (uint32_t a, uint32_t b)
123{
124 int32_t d = b - a;
125 d &= d >> 31;
126 return a + d;
127}
128
129// Both a and b must not have the most significant bit set
130static inline uint32_t
131upos_max (uint32_t a, uint32_t b)
132{
133 int32_t d = b - a;
134 d &= d >> 31;
135 return b - d;
136}
39 137
40// this is much faster than crossfires original algorithm 138// this is much faster than crossfires original algorithm
41// on modern cpus 139// on modern cpus
42inline int 140inline int
43isqrt (int n) 141isqrt (int n)
… …
125 223
126// for symmetry 224// for symmetry
127template<typename T> 225template<typename T>
128inline void sfree (T *ptr, int n = 1) throw () 226inline void sfree (T *ptr, int n = 1) throw ()
129{ 227{
228#ifdef PREFER_MALLOC
229 free (ptr);
230#else
130 g_slice_free1 (n * sizeof (T), (void *)ptr); 231 g_slice_free1 (n * sizeof (T), (void *)ptr);
232#endif
131} 233}
132 234
133// a STL-compatible allocator that uses g_slice 235// a STL-compatible allocator that uses g_slice
134// boy, this is verbose 236// boy, this is verbose
135template<typename Tp> 237template<typename Tp>
… …
182 void destroy (pointer p) 284 void destroy (pointer p)
183 { 285 {
184 p->~Tp (); 286 p->~Tp ();
185 } 287 }
186}; 288};
289
290// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
291// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
292// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
293struct tausworthe_random_generator
294{
295 // generator
296 uint32_t state [4];
297
298 void operator =(const tausworthe_random_generator &src)
299 {
300 state [0] = src.state [0];
301 state [1] = src.state [1];
302 state [2] = src.state [2];
303 state [3] = src.state [3];
304 }
305
306 void seed (uint32_t seed);
307 uint32_t next ();
308
309 // uniform distribution
310 uint32_t operator ()(uint32_t num)
311 {
312 return is_constant (num)
313 ? (next () * (uint64_t)num) >> 32U
314 : get_range (num);
315 }
316
317 // return a number within (min .. max)
318 int operator () (int r_min, int r_max)
319 {
320 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
321 ? r_min + operator ()(r_max - r_min + 1)
322 : get_range (r_min, r_max);
323 }
324
325 double operator ()()
326 {
327 return this->next () / (double)0xFFFFFFFFU;
328 }
329
330protected:
331 uint32_t get_range (uint32_t r_max);
332 int get_range (int r_min, int r_max);
333};
334
335typedef tausworthe_random_generator rand_gen;
336
337extern rand_gen rndm;
187 338
188template<class T> 339template<class T>
189struct refptr 340struct refptr
190{ 341{
191 T *p; 342 T *p;
… …
254 { 405 {
255 return !strcmp (a, b); 406 return !strcmp (a, b);
256 } 407 }
257}; 408};
258 409
410// Mostly the same as std::vector, but insert/erase can reorder
411// the elements, making insret/remove O(1) instead of O(n).
412//
413// NOTE: only some forms of erase/insert are available
259template<class T> 414template<class T>
260struct unordered_vector : std::vector<T, slice_allocator<T> > 415struct unordered_vector : std::vector<T, slice_allocator<T> >
261{ 416{
262 typedef typename unordered_vector::iterator iterator; 417 typedef typename unordered_vector::iterator iterator;
263 418
… …
273 { 428 {
274 erase ((unsigned int )(i - this->begin ())); 429 erase ((unsigned int )(i - this->begin ()));
275 } 430 }
276}; 431};
277 432
433// This container blends advantages of linked lists
434// (efficiency) with vectors (random access) by
435// by using an unordered vector and storing the vector
436// index inside the object.
437//
438// + memory-efficient on most 64 bit archs
439// + O(1) insert/remove
440// + free unique (but varying) id for inserted objects
441// + cache-friendly iteration
442// - only works for pointers to structs
443//
444// NOTE: only some forms of erase/insert are available
278template<class T, int T::* index> 445template<class T, int T::* index>
279struct object_vector : std::vector<T *, slice_allocator<T *> > 446struct object_vector : std::vector<T *, slice_allocator<T *> >
280{ 447{
448 typedef typename object_vector::iterator iterator;
449
450 bool contains (const T *obj) const
451 {
452 return obj->*index;
453 }
454
455 iterator find (const T *obj)
456 {
457 return obj->*index
458 ? this->begin () + obj->*index - 1
459 : this->end ();
460 }
461
281 void insert (T *obj) 462 void insert (T *obj)
282 { 463 {
283 assert (!(obj->*index));
284 push_back (obj); 464 push_back (obj);
285 obj->*index = this->size (); 465 obj->*index = this->size ();
286 } 466 }
287 467
288 void insert (T &obj) 468 void insert (T &obj)
… …
290 insert (&obj); 470 insert (&obj);
291 } 471 }
292 472
293 void erase (T *obj) 473 void erase (T *obj)
294 { 474 {
295 assert (obj->*index);
296 int pos = obj->*index; 475 unsigned int pos = obj->*index;
297 obj->*index = 0; 476 obj->*index = 0;
298 477
299 if (pos < this->size ()) 478 if (pos < this->size ())
300 { 479 {
301 (*this)[pos - 1] = (*this)[this->size () - 1]; 480 (*this)[pos - 1] = (*this)[this->size () - 1];
… …
309 { 488 {
310 errase (&obj); 489 errase (&obj);
311 } 490 }
312}; 491};
313 492
314template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
315template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
316template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? a : v >(T)b ? b : v; }
317
318template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
319
320// basically does what strncpy should do, but appends "..." to strings exceeding length 493// basically does what strncpy should do, but appends "..." to strings exceeding length
321void assign (char *dst, const char *src, int maxlen); 494void assign (char *dst, const char *src, int maxlen);
322 495
323// type-safe version of assign 496// type-safe version of assign
324template<int N> 497template<int N>
… …
332// return current time as timestampe 505// return current time as timestampe
333tstamp now (); 506tstamp now ();
334 507
335int similar_direction (int a, int b); 508int similar_direction (int a, int b);
336 509
510// like printf, but returns a std::string
511const std::string format (const char *format, ...);
512
337#endif 513#endif
338 514

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