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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 1.56 by root, Sun Sep 9 06:25:46 2007 UTC

1/*
2 * This file is part of Crossfire TRT, the Roguelike Realtime MORPG.
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
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 * The authors can be reached via e-mail to <crossfire@schmorp.de>
20 */
21
1#ifndef UTIL_H__ 22#ifndef UTIL_H__
2#define UTIL_H__ 23#define UTIL_H__
3 24
25//#define PREFER_MALLOC
26
4#if __GNUC__ >= 3 27#if __GNUC__ >= 3
5# define is_constant(c) __builtin_constant_p (c) 28# define is_constant(c) __builtin_constant_p (c)
29# define expect(expr,value) __builtin_expect ((expr),(value))
30# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
6#else 31#else
7# define is_constant(c) 0 32# define is_constant(c) 0
33# define expect(expr,value) (expr)
34# define prefetch(addr,rw,locality)
8#endif 35#endif
36
37#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
38# define decltype(x) typeof(x)
39#endif
40
41// put into ifs if you are very sure that the expression
42// is mostly true or mosty false. note that these return
43// booleans, not the expression.
44#define expect_false(expr) expect ((expr) != 0, 0)
45#define expect_true(expr) expect ((expr) != 0, 1)
9 46
10#include <cstddef> 47#include <cstddef>
11#include <cmath> 48#include <cmath>
12#include <new> 49#include <new>
13#include <vector> 50#include <vector>
15#include <glib.h> 52#include <glib.h>
16 53
17#include <shstr.h> 54#include <shstr.h>
18#include <traits.h> 55#include <traits.h>
19 56
20// use a gcc extension for auto declarations until ISO C++ sanctifies them 57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
21#define AUTODECL(var,expr) typeof(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
22 59
23// very ugly macro that basicaly declares and initialises a variable 60// very ugly macro that basicaly declares and initialises a variable
24// that is in scope for the next statement only 61// that is in scope for the next statement only
25// works only for stuff that can be assigned 0 and converts to false 62// works only for stuff that can be assigned 0 and converts to false
26// (note: works great for pointers) 63// (note: works great for pointers)
27// most ugly macro I ever wrote 64// most ugly macro I ever wrote
28#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 65#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
29 66
30// in range including end 67// in range including end
31#define IN_RANGE_INC(val,beg,end) \ 68#define IN_RANGE_INC(val,beg,end) \
32 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg)) 69 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
33 70
34// in range excluding end 71// in range excluding end
35#define IN_RANGE_EXC(val,beg,end) \ 72#define IN_RANGE_EXC(val,beg,end) \
36 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg)) 73 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
37 74
38void fork_abort (const char *msg); 75void fork_abort (const char *msg);
76
77// rationale for using (U) not (T) is to reduce signed/unsigned issues,
78// as a is often a constant while b is the variable. it is still a bug, though.
79template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
80template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
81template<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; }
82
83template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
84
85template<typename T>
86static inline T
87lerp (T val, T min_in, T max_in, T min_out, T max_out)
88{
89 return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
90}
91
92// lots of stuff taken from FXT
93
94/* Rotate right. This is used in various places for checksumming */
95//TODO: that sucks, use a better checksum algo
96static inline uint32_t
97rotate_right (uint32_t c, uint32_t count = 1)
98{
99 return (c << (32 - count)) | (c >> count);
100}
101
102static inline uint32_t
103rotate_left (uint32_t c, uint32_t count = 1)
104{
105 return (c >> (32 - count)) | (c << count);
106}
107
108// Return abs(a-b)
109// Both a and b must not have the most significant bit set
110static inline uint32_t
111upos_abs_diff (uint32_t a, uint32_t b)
112{
113 long d1 = b - a;
114 long d2 = (d1 & (d1 >> 31)) << 1;
115
116 return d1 - d2; // == (b - d) - (a + d);
117}
118
119// Both a and b must not have the most significant bit set
120static inline uint32_t
121upos_min (uint32_t a, uint32_t b)
122{
123 int32_t d = b - a;
124 d &= d >> 31;
125 return a + d;
126}
127
128// Both a and b must not have the most significant bit set
129static inline uint32_t
130upos_max (uint32_t a, uint32_t b)
131{
132 int32_t d = b - a;
133 d &= d >> 31;
134 return b - d;
135}
39 136
40// this is much faster than crossfires original algorithm 137// this is much faster than crossfires original algorithm
41// on modern cpus 138// on modern cpus
42inline int 139inline int
43isqrt (int n) 140isqrt (int n)
125 222
126// for symmetry 223// for symmetry
127template<typename T> 224template<typename T>
128inline void sfree (T *ptr, int n = 1) throw () 225inline void sfree (T *ptr, int n = 1) throw ()
129{ 226{
227#ifdef PREFER_MALLOC
228 free (ptr);
229#else
130 g_slice_free1 (n * sizeof (T), (void *)ptr); 230 g_slice_free1 (n * sizeof (T), (void *)ptr);
231#endif
131} 232}
132 233
133// a STL-compatible allocator that uses g_slice 234// a STL-compatible allocator that uses g_slice
134// boy, this is verbose 235// boy, this is verbose
135template<typename Tp> 236template<typename Tp>
183 { 284 {
184 p->~Tp (); 285 p->~Tp ();
185 } 286 }
186}; 287};
187 288
289// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
290// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
291// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
292struct tausworthe_random_generator
293{
294 // generator
295 uint32_t state [4];
296
297 void operator =(const tausworthe_random_generator &src)
298 {
299 state [0] = src.state [0];
300 state [1] = src.state [1];
301 state [2] = src.state [2];
302 state [3] = src.state [3];
303 }
304
305 void seed (uint32_t seed);
306 uint32_t next ();
307
308 // uniform distribution
309 uint32_t operator ()(uint32_t num)
310 {
311 return is_constant (num)
312 ? (next () * (uint64_t)num) >> 32U
313 : get_range (num);
314 }
315
316 // return a number within (min .. max)
317 int operator () (int r_min, int r_max)
318 {
319 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
320 ? r_min + operator ()(r_max - r_min + 1)
321 : get_range (r_min, r_max);
322 }
323
324 double operator ()()
325 {
326 return this->next () / (double)0xFFFFFFFFU;
327 }
328
329protected:
330 uint32_t get_range (uint32_t r_max);
331 int get_range (int r_min, int r_max);
332};
333
334typedef tausworthe_random_generator rand_gen;
335
336extern rand_gen rndm;
337
338INTERFACE_CLASS (attachable)
339struct refcnt_base
340{
341 typedef int refcnt_t;
342 mutable refcnt_t ACC (RW, refcnt);
343
344 MTH void refcnt_inc () const { ++refcnt; }
345 MTH void refcnt_dec () const { --refcnt; }
346
347 refcnt_base () : refcnt (0) { }
348};
349
350// to avoid branches with more advanced compilers
351extern refcnt_base::refcnt_t refcnt_dummy;
352
188template<class T> 353template<class T>
189struct refptr 354struct refptr
190{ 355{
356 // p if not null
357 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
358
359 void refcnt_dec ()
360 {
361 if (!is_constant (p))
362 --*refcnt_ref ();
363 else if (p)
364 --p->refcnt;
365 }
366
367 void refcnt_inc ()
368 {
369 if (!is_constant (p))
370 ++*refcnt_ref ();
371 else if (p)
372 ++p->refcnt;
373 }
374
191 T *p; 375 T *p;
192 376
193 refptr () : p(0) { } 377 refptr () : p(0) { }
194 refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); } 378 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
195 refptr (T *p) : p(p) { if (p) p->refcnt_inc (); } 379 refptr (T *p) : p(p) { refcnt_inc (); }
196 ~refptr () { if (p) p->refcnt_dec (); } 380 ~refptr () { refcnt_dec (); }
197 381
198 const refptr<T> &operator =(T *o) 382 const refptr<T> &operator =(T *o)
199 { 383 {
384 // if decrementing ever destroys we need to reverse the order here
200 if (p) p->refcnt_dec (); 385 refcnt_dec ();
201 p = o; 386 p = o;
202 if (p) p->refcnt_inc (); 387 refcnt_inc ();
203
204 return *this; 388 return *this;
205 } 389 }
206 390
207 const refptr<T> &operator =(const refptr<T> o) 391 const refptr<T> &operator =(const refptr<T> &o)
208 { 392 {
209 *this = o.p; 393 *this = o.p;
210 return *this; 394 return *this;
211 } 395 }
212 396
213 T &operator * () const { return *p; } 397 T &operator * () const { return *p; }
214 T *operator ->() const { return p; } 398 T *operator ->() const { return p; }
215 399
216 operator T *() const { return p; } 400 operator T *() const { return p; }
217}; 401};
218 402
219typedef refptr<maptile> maptile_ptr; 403typedef refptr<maptile> maptile_ptr;
254 { 438 {
255 return !strcmp (a, b); 439 return !strcmp (a, b);
256 } 440 }
257}; 441};
258 442
443// Mostly the same as std::vector, but insert/erase can reorder
444// the elements, making append(=insert)/remove O(1) instead of O(n).
445//
446// NOTE: only some forms of erase are available
259template<class T> 447template<class T>
260struct unordered_vector : std::vector<T, slice_allocator<T> > 448struct unordered_vector : std::vector<T, slice_allocator<T> >
261{ 449{
262 typedef typename unordered_vector::iterator iterator; 450 typedef typename unordered_vector::iterator iterator;
263 451
273 { 461 {
274 erase ((unsigned int )(i - this->begin ())); 462 erase ((unsigned int )(i - this->begin ()));
275 } 463 }
276}; 464};
277 465
278template<class T, int T::* index> 466// This container blends advantages of linked lists
467// (efficiency) with vectors (random access) by
468// by using an unordered vector and storing the vector
469// index inside the object.
470//
471// + memory-efficient on most 64 bit archs
472// + O(1) insert/remove
473// + free unique (but varying) id for inserted objects
474// + cache-friendly iteration
475// - only works for pointers to structs
476//
477// NOTE: only some forms of erase/insert are available
478typedef int object_vector_index;
479
480template<class T, object_vector_index T::*indexmember>
279struct object_vector : std::vector<T *, slice_allocator<T *> > 481struct object_vector : std::vector<T *, slice_allocator<T *> >
280{ 482{
483 typedef typename object_vector::iterator iterator;
484
485 bool contains (const T *obj) const
486 {
487 return obj->*indexmember;
488 }
489
490 iterator find (const T *obj)
491 {
492 return obj->*indexmember
493 ? this->begin () + obj->*indexmember - 1
494 : this->end ();
495 }
496
497 void push_back (T *obj)
498 {
499 std::vector<T *, slice_allocator<T *> >::push_back (obj);
500 obj->*indexmember = this->size ();
501 }
502
281 void insert (T *obj) 503 void insert (T *obj)
282 { 504 {
283 assert (!(obj->*index));
284 push_back (obj); 505 push_back (obj);
285 obj->*index = this->size ();
286 } 506 }
287 507
288 void insert (T &obj) 508 void insert (T &obj)
289 { 509 {
290 insert (&obj); 510 insert (&obj);
291 } 511 }
292 512
293 void erase (T *obj) 513 void erase (T *obj)
294 { 514 {
295 assert (obj->*index);
296 int pos = obj->*index; 515 unsigned int pos = obj->*indexmember;
297 obj->*index = 0; 516 obj->*indexmember = 0;
298 517
299 if (pos < this->size ()) 518 if (pos < this->size ())
300 { 519 {
301 (*this)[pos - 1] = (*this)[this->size () - 1]; 520 (*this)[pos - 1] = (*this)[this->size () - 1];
302 (*this)[pos - 1]->*index = pos; 521 (*this)[pos - 1]->*indexmember = pos;
303 } 522 }
304 523
305 this->pop_back (); 524 this->pop_back ();
306 } 525 }
307 526
308 void erase (T &obj) 527 void erase (T &obj)
309 { 528 {
310 errase (&obj); 529 erase (&obj);
311 } 530 }
312}; 531};
313
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; }
319 532
320// basically does what strncpy should do, but appends "..." to strings exceeding length 533// basically does what strncpy should do, but appends "..." to strings exceeding length
321void assign (char *dst, const char *src, int maxlen); 534void assign (char *dst, const char *src, int maxlen);
322 535
323// type-safe version of assign 536// type-safe version of assign
332// return current time as timestampe 545// return current time as timestampe
333tstamp now (); 546tstamp now ();
334 547
335int similar_direction (int a, int b); 548int similar_direction (int a, int b);
336 549
550// like sprintf, but returns a "static" buffer
551const char *format (const char *format, ...);
552
337#endif 553#endif
338 554

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