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Comparing deliantra/server/include/util.h (file contents):
Revision 1.36 by root, Thu Jan 25 03:54:45 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
4//#define PREFER_MALLOC 25//#define PREFER_MALLOC
5 26
6#if __GNUC__ >= 3 27#if __GNUC__ >= 3
7# 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)
8#else 31#else
9# define is_constant(c) 0 32# define is_constant(c) 0
33# define expect(expr,value) (expr)
34# define prefetch(addr,rw,locality)
10#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)
11 46
12#include <cstddef> 47#include <cstddef>
13#include <cmath> 48#include <cmath>
14#include <new> 49#include <new>
15#include <vector> 50#include <vector>
… …
17#include <glib.h> 52#include <glib.h>
18 53
19#include <shstr.h> 54#include <shstr.h>
20#include <traits.h> 55#include <traits.h>
21 56
22// 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)
23#define AUTODECL(var,expr) typeof(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
24 59
25// very ugly macro that basicaly declares and initialises a variable 60// very ugly macro that basicaly declares and initialises a variable
26// that is in scope for the next statement only 61// that is in scope for the next statement only
27// 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
28// (note: works great for pointers) 63// (note: works great for pointers)
29// most ugly macro I ever wrote 64// most ugly macro I ever wrote
30#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)
31 66
32// in range including end 67// in range including end
33#define IN_RANGE_INC(val,beg,end) \ 68#define IN_RANGE_INC(val,beg,end) \
34 ((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))
35 70
… …
44template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; } 79template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
45template<typename T, typename U> static inline T max (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; }
46template<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; } 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; }
47 82
48template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } 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}
49 136
50// this is much faster than crossfires original algorithm 137// this is much faster than crossfires original algorithm
51// on modern cpus 138// on modern cpus
52inline int 139inline int
53isqrt (int n) 140isqrt (int n)
… …
217 304
218 void seed (uint32_t seed); 305 void seed (uint32_t seed);
219 uint32_t next (); 306 uint32_t next ();
220 307
221 // uniform distribution 308 // uniform distribution
222 uint32_t operator ()(uint32_t r_max) 309 uint32_t operator ()(uint32_t num)
223 { 310 {
224 return is_constant (r_max) 311 return is_constant (num)
225 ? this->next () % r_max 312 ? (next () * (uint64_t)num) >> 32U
226 : get_range (r_max); 313 : get_range (num);
227 } 314 }
228 315
229 // return a number within (min .. max) 316 // return a number within (min .. max)
230 int operator () (int r_min, int r_max) 317 int operator () (int r_min, int r_max)
231 { 318 {
232 return is_constant (r_min) && is_constant (r_max) 319 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
233 ? r_min + (*this) (max (r_max - r_min + 1, 1)) 320 ? r_min + operator ()(r_max - r_min + 1)
234 : get_range (r_min, r_max); 321 : get_range (r_min, r_max);
235 } 322 }
236 323
237 double operator ()() 324 double operator ()()
238 { 325 {
… …
246 333
247typedef tausworthe_random_generator rand_gen; 334typedef tausworthe_random_generator rand_gen;
248 335
249extern rand_gen rndm; 336extern rand_gen rndm;
250 337
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
251template<class T> 353template<class T>
252struct refptr 354struct refptr
253{ 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
254 T *p; 375 T *p;
255 376
256 refptr () : p(0) { } 377 refptr () : p(0) { }
257 refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); } 378 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
258 refptr (T *p) : p(p) { if (p) p->refcnt_inc (); } 379 refptr (T *p) : p(p) { refcnt_inc (); }
259 ~refptr () { if (p) p->refcnt_dec (); } 380 ~refptr () { refcnt_dec (); }
260 381
261 const refptr<T> &operator =(T *o) 382 const refptr<T> &operator =(T *o)
262 { 383 {
384 // if decrementing ever destroys we need to reverse the order here
263 if (p) p->refcnt_dec (); 385 refcnt_dec ();
264 p = o; 386 p = o;
265 if (p) p->refcnt_inc (); 387 refcnt_inc ();
266
267 return *this; 388 return *this;
268 } 389 }
269 390
270 const refptr<T> &operator =(const refptr<T> o) 391 const refptr<T> &operator =(const refptr<T> &o)
271 { 392 {
272 *this = o.p; 393 *this = o.p;
273 return *this; 394 return *this;
274 } 395 }
275 396
276 T &operator * () const { return *p; } 397 T &operator * () const { return *p; }
277 T *operator ->() const { return p; } 398 T *operator ->() const { return p; }
278 399
279 operator T *() const { return p; } 400 operator T *() const { return p; }
280}; 401};
281 402
282typedef refptr<maptile> maptile_ptr; 403typedef refptr<maptile> maptile_ptr;
… …
317 { 438 {
318 return !strcmp (a, b); 439 return !strcmp (a, b);
319 } 440 }
320}; 441};
321 442
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
322template<class T> 447template<class T>
323struct unordered_vector : std::vector<T, slice_allocator<T> > 448struct unordered_vector : std::vector<T, slice_allocator<T> >
324{ 449{
325 typedef typename unordered_vector::iterator iterator; 450 typedef typename unordered_vector::iterator iterator;
326 451
… …
336 { 461 {
337 erase ((unsigned int )(i - this->begin ())); 462 erase ((unsigned int )(i - this->begin ()));
338 } 463 }
339}; 464};
340 465
341template<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>
342struct object_vector : std::vector<T *, slice_allocator<T *> > 481struct object_vector : std::vector<T *, slice_allocator<T *> >
343{ 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
344 void insert (T *obj) 503 void insert (T *obj)
345 { 504 {
346 assert (!(obj->*index));
347 push_back (obj); 505 push_back (obj);
348 obj->*index = this->size ();
349 } 506 }
350 507
351 void insert (T &obj) 508 void insert (T &obj)
352 { 509 {
353 insert (&obj); 510 insert (&obj);
354 } 511 }
355 512
356 void erase (T *obj) 513 void erase (T *obj)
357 { 514 {
358 assert (obj->*index);
359 int pos = obj->*index; 515 unsigned int pos = obj->*indexmember;
360 obj->*index = 0; 516 obj->*indexmember = 0;
361 517
362 if (pos < this->size ()) 518 if (pos < this->size ())
363 { 519 {
364 (*this)[pos - 1] = (*this)[this->size () - 1]; 520 (*this)[pos - 1] = (*this)[this->size () - 1];
365 (*this)[pos - 1]->*index = pos; 521 (*this)[pos - 1]->*indexmember = pos;
366 } 522 }
367 523
368 this->pop_back (); 524 this->pop_back ();
369 } 525 }
370 526
371 void erase (T &obj) 527 void erase (T &obj)
372 { 528 {
373 errase (&obj); 529 erase (&obj);
374 } 530 }
375}; 531};
376 532
377// 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
378void assign (char *dst, const char *src, int maxlen); 534void assign (char *dst, const char *src, int maxlen);
… …
389// return current time as timestampe 545// return current time as timestampe
390tstamp now (); 546tstamp now ();
391 547
392int similar_direction (int a, int b); 548int similar_direction (int a, int b);
393 549
550// like sprintf, but returns a "static" buffer
551const char *format (const char *format, ...);
552
394#endif 553#endif
395 554

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