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Comparing deliantra/server/include/util.h (file contents):
Revision 1.20 by root, Sun Dec 17 23:10:35 2006 UTC vs.
Revision 1.50 by root, Sun Jun 24 00:33:54 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
9 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)
47
10#include <cstddef> 48#include <cstddef>
49#include <cmath>
50#include <new>
51#include <vector>
11 52
12#include <glib.h> 53#include <glib.h>
13 54
55#include <shstr.h>
56#include <traits.h>
57
14// 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)
15#define AUTODECL(var,expr) typeof(expr) var = (expr) 59#define auto(var,expr) decltype(expr) var = (expr)
60
61// very ugly macro that basicaly declares and initialises a variable
62// that is in scope for the next statement only
63// works only for stuff that can be assigned 0 and converts to false
64// (note: works great for pointers)
65// most ugly macro I ever wrote
66#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
67
68// in range including end
69#define IN_RANGE_INC(val,beg,end) \
70 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
71
72// in range excluding end
73#define IN_RANGE_EXC(val,beg,end) \
74 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
75
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}
137
138// this is much faster than crossfires original algorithm
139// on modern cpus
140inline int
141isqrt (int n)
142{
143 return (int)sqrtf ((float)n);
144}
145
146// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
147#if 0
148// and has a max. error of 6 in the range -100..+100.
149#else
150// and has a max. error of 9 in the range -100..+100.
151#endif
152inline int
153idistance (int dx, int dy)
154{
155 unsigned int dx_ = abs (dx);
156 unsigned int dy_ = abs (dy);
157
158#if 0
159 return dx_ > dy_
160 ? (dx_ * 61685 + dy_ * 26870) >> 16
161 : (dy_ * 61685 + dx_ * 26870) >> 16;
162#else
163 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
164#endif
165}
166
167/*
168 * absdir(int): Returns a number between 1 and 8, which represent
169 * the "absolute" direction of a number (it actually takes care of
170 * "overflow" in previous calculations of a direction).
171 */
172inline int
173absdir (int d)
174{
175 return ((d - 1) & 7) + 1;
176}
16 177
17// makes dynamically allocated objects zero-initialised 178// makes dynamically allocated objects zero-initialised
18struct zero_initialised 179struct zero_initialised
19{ 180{
20 void *operator new (size_t s, void *p) 181 void *operator new (size_t s, void *p)
54// also copies src into the new area, like "memdup" 215// also copies src into the new area, like "memdup"
55// if src is 0, clears the memory 216// if src is 0, clears the memory
56template<typename T> 217template<typename T>
57inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); } 218inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
58 219
220// clears the memory
221template<typename T>
222inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); }
223
59// for symmetry 224// for symmetry
60template<typename T> 225template<typename T>
61inline void sfree (T *ptr, int n = 1) throw () 226inline void sfree (T *ptr, int n = 1) throw ()
62{ 227{
228#ifdef PREFER_MALLOC
229 free (ptr);
230#else
63 g_slice_free1 (n * sizeof (T), (void *)ptr); 231 g_slice_free1 (n * sizeof (T), (void *)ptr);
232#endif
64} 233}
65 234
66// a STL-compatible allocator that uses g_slice 235// a STL-compatible allocator that uses g_slice
67// boy, this is verbose 236// boy, this is verbose
68template<typename Tp> 237template<typename Tp>
116 { 285 {
117 p->~Tp (); 286 p->~Tp ();
118 } 287 }
119}; 288};
120 289
121struct refcounted 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
122{ 294{
123 refcounted () : refcnt (0) { } 295 // generator
124// virtual ~refcounted (); 296 uint32_t state [4];
125 void refcnt_inc () { ++refcnt; } 297
126 void refcnt_dec () { --refcnt; } 298 void operator =(const tausworthe_random_generator &src)
127 bool dead () { return refcnt == 0; } 299 {
128 mutable int refcnt; 300 state [0] = src.state [0];
129#if 0 301 state [1] = src.state [1];
130private: 302 state [2] = src.state [2];
131 static refcounted *rc_first; 303 state [3] = src.state [3];
132 refcounted *rc_next; 304 }
133#endif 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);
134}; 333};
334
335typedef tausworthe_random_generator rand_gen;
336
337extern rand_gen rndm;
135 338
136template<class T> 339template<class T>
137struct refptr 340struct refptr
138{ 341{
139 T *p; 342 T *p;
161 T &operator * () const { return *p; } 364 T &operator * () const { return *p; }
162 T *operator ->() const { return p; } 365 T *operator ->() const { return p; }
163 366
164 operator T *() const { return p; } 367 operator T *() const { return p; }
165}; 368};
369
370typedef refptr<maptile> maptile_ptr;
371typedef refptr<object> object_ptr;
372typedef refptr<archetype> arch_ptr;
373typedef refptr<client> client_ptr;
374typedef refptr<player> player_ptr;
166 375
167struct str_hash 376struct str_hash
168{ 377{
169 std::size_t operator ()(const char *s) const 378 std::size_t operator ()(const char *s) const
170 { 379 {
196 { 405 {
197 return !strcmp (a, b); 406 return !strcmp (a, b);
198 } 407 }
199}; 408};
200 409
201#include <vector> 410// Mostly the same as std::vector, but insert/erase can reorder
202 411// the elements, making insret/remove O(1) instead of O(n).
412//
413// NOTE: only some forms of erase/insert are available
203template<class obj> 414template<class T>
204struct unordered_vector : std::vector<obj, slice_allocator<obj> > 415struct unordered_vector : std::vector<T, slice_allocator<T> >
205{ 416{
206 typedef typename unordered_vector::iterator iterator; 417 typedef typename unordered_vector::iterator iterator;
207 418
208 void erase (unsigned int pos) 419 void erase (unsigned int pos)
209 { 420 {
217 { 428 {
218 erase ((unsigned int )(i - this->begin ())); 429 erase ((unsigned int )(i - this->begin ()));
219 } 430 }
220}; 431};
221 432
222template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; } 433// This container blends advantages of linked lists
223template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; } 434// (efficiency) with vectors (random access) by
224template<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; } 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
445typedef int object_vector_index;
225 446
226template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } 447template<class T, object_vector_index T::*indexmember>
448struct object_vector : std::vector<T *, slice_allocator<T *> >
449{
450 typedef typename object_vector::iterator iterator;
451
452 bool contains (const T *obj) const
453 {
454 return obj->*indexmember;
455 }
456
457 iterator find (const T *obj)
458 {
459 return obj->*indexmember
460 ? this->begin () + obj->*indexmember - 1
461 : this->end ();
462 }
463
464 void insert (T *obj)
465 {
466 push_back (obj);
467 obj->*indexmember = this->size ();
468 }
469
470 void insert (T &obj)
471 {
472 insert (&obj);
473 }
474
475 void erase (T *obj)
476 {
477 unsigned int pos = obj->*indexmember;
478 obj->*indexmember = 0;
479
480 if (pos < this->size ())
481 {
482 (*this)[pos - 1] = (*this)[this->size () - 1];
483 (*this)[pos - 1]->*indexmember = pos;
484 }
485
486 this->pop_back ();
487 }
488
489 void erase (T &obj)
490 {
491 erase (&obj);
492 }
493};
227 494
228// basically does what strncpy should do, but appends "..." to strings exceeding length 495// basically does what strncpy should do, but appends "..." to strings exceeding length
229void assign (char *dst, const char *src, int maxlen); 496void assign (char *dst, const char *src, int maxlen);
230 497
231// type-safe version of assign 498// type-safe version of assign
238typedef double tstamp; 505typedef double tstamp;
239 506
240// return current time as timestampe 507// return current time as timestampe
241tstamp now (); 508tstamp now ();
242 509
510int similar_direction (int a, int b);
511
512// like printf, but returns a std::string
513const std::string format (const char *format, ...);
514
243#endif 515#endif
244 516

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