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Comparing deliantra/server/include/util.h (file contents):
Revision 1.34 by root, Fri Jan 19 15:15:50 2007 UTC vs.
Revision 1.55 by root, Thu Aug 16 06:36:56 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
… …
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);
39 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.
40template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; } 79template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
41template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; } 80template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
42template<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; } 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; }
43 82
44template<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}
45 136
46// this is much faster than crossfires original algorithm 137// this is much faster than crossfires original algorithm
47// on modern cpus 138// on modern cpus
48inline int 139inline int
49isqrt (int n) 140isqrt (int n)
… …
131 222
132// for symmetry 223// for symmetry
133template<typename T> 224template<typename T>
134inline void sfree (T *ptr, int n = 1) throw () 225inline void sfree (T *ptr, int n = 1) throw ()
135{ 226{
227#ifdef PREFER_MALLOC
228 free (ptr);
229#else
136 g_slice_free1 (n * sizeof (T), (void *)ptr); 230 g_slice_free1 (n * sizeof (T), (void *)ptr);
231#endif
137} 232}
138 233
139// a STL-compatible allocator that uses g_slice 234// a STL-compatible allocator that uses g_slice
140// boy, this is verbose 235// boy, this is verbose
141template<typename Tp> 236template<typename Tp>
… …
209 304
210 void seed (uint32_t seed); 305 void seed (uint32_t seed);
211 uint32_t next (); 306 uint32_t next ();
212 307
213 // uniform distribution 308 // uniform distribution
214 uint32_t operator ()(uint32_t r_max) 309 uint32_t operator ()(uint32_t num)
215 { 310 {
216 return is_constant (r_max) 311 return is_constant (num)
217 ? this->next () % r_max 312 ? (next () * (uint64_t)num) >> 32U
218 : get_range (r_max); 313 : get_range (num);
219 } 314 }
220 315
221 // return a number within (min .. max) 316 // return a number within (min .. max)
222 int operator () (int r_min, int r_max) 317 int operator () (int r_min, int r_max)
223 { 318 {
224 return is_constant (r_min) && is_constant (r_max) 319 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
225 ? r_min + (*this) (max (r_max - r_min + 1, 1)) 320 ? r_min + operator ()(r_max - r_min + 1)
226 : get_range (r_min, r_max); 321 : get_range (r_min, r_max);
227 } 322 }
228 323
229 double operator ()() 324 double operator ()()
230 { 325 {
… …
238 333
239typedef tausworthe_random_generator rand_gen; 334typedef tausworthe_random_generator rand_gen;
240 335
241extern rand_gen rndm; 336extern rand_gen rndm;
242 337
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
350extern refcnt_base::refcnt_t refcnt_dummy;
351
243template<class T> 352template<class T>
244struct refptr 353struct refptr
245{ 354{
355 // p if not null
356 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
357
358 void refcnt_dec ()
359 {
360 if (!is_constant (p))
361 --*refcnt_ref ();
362 else if (p)
363 --p->refcnt;
364 }
365
366 void refcnt_inc ()
367 {
368 if (!is_constant (p))
369 ++*refcnt_ref ();
370 else if (p)
371 ++p->refcnt;
372 }
373
246 T *p; 374 T *p;
247 375
248 refptr () : p(0) { } 376 refptr () : p(0) { }
249 refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); } 377 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
250 refptr (T *p) : p(p) { if (p) p->refcnt_inc (); } 378 refptr (T *p) : p(p) { refcnt_inc (); }
251 ~refptr () { if (p) p->refcnt_dec (); } 379 ~refptr () { refcnt_dec (); }
252 380
253 const refptr<T> &operator =(T *o) 381 const refptr<T> &operator =(T *o)
254 { 382 {
383 // if decrementing ever destroys we need to reverse the order here
255 if (p) p->refcnt_dec (); 384 refcnt_dec ();
256 p = o; 385 p = o;
257 if (p) p->refcnt_inc (); 386 refcnt_inc ();
258
259 return *this; 387 return *this;
260 } 388 }
261 389
262 const refptr<T> &operator =(const refptr<T> o) 390 const refptr<T> &operator =(const refptr<T> &o)
263 { 391 {
264 *this = o.p; 392 *this = o.p;
265 return *this; 393 return *this;
266 } 394 }
267 395
268 T &operator * () const { return *p; } 396 T &operator * () const { return *p; }
269 T *operator ->() const { return p; } 397 T *operator ->() const { return p; }
270 398
271 operator T *() const { return p; } 399 operator T *() const { return p; }
272}; 400};
273 401
274typedef refptr<maptile> maptile_ptr; 402typedef refptr<maptile> maptile_ptr;
… …
309 { 437 {
310 return !strcmp (a, b); 438 return !strcmp (a, b);
311 } 439 }
312}; 440};
313 441
442// Mostly the same as std::vector, but insert/erase can reorder
443// the elements, making append(=insert)/remove O(1) instead of O(n).
444//
445// NOTE: only some forms of erase are available
314template<class T> 446template<class T>
315struct unordered_vector : std::vector<T, slice_allocator<T> > 447struct unordered_vector : std::vector<T, slice_allocator<T> >
316{ 448{
317 typedef typename unordered_vector::iterator iterator; 449 typedef typename unordered_vector::iterator iterator;
318 450
… …
328 { 460 {
329 erase ((unsigned int )(i - this->begin ())); 461 erase ((unsigned int )(i - this->begin ()));
330 } 462 }
331}; 463};
332 464
333template<class T, int T::* index> 465// This container blends advantages of linked lists
466// (efficiency) with vectors (random access) by
467// by using an unordered vector and storing the vector
468// index inside the object.
469//
470// + memory-efficient on most 64 bit archs
471// + O(1) insert/remove
472// + free unique (but varying) id for inserted objects
473// + cache-friendly iteration
474// - only works for pointers to structs
475//
476// NOTE: only some forms of erase/insert are available
477typedef int object_vector_index;
478
479template<class T, object_vector_index T::*indexmember>
334struct object_vector : std::vector<T *, slice_allocator<T *> > 480struct object_vector : std::vector<T *, slice_allocator<T *> >
335{ 481{
482 typedef typename object_vector::iterator iterator;
483
484 bool contains (const T *obj) const
485 {
486 return obj->*indexmember;
487 }
488
489 iterator find (const T *obj)
490 {
491 return obj->*indexmember
492 ? this->begin () + obj->*indexmember - 1
493 : this->end ();
494 }
495
496 void push_back (T *obj)
497 {
498 std::vector<T *, slice_allocator<T *> >::push_back (obj);
499 obj->*indexmember = this->size ();
500 }
501
336 void insert (T *obj) 502 void insert (T *obj)
337 { 503 {
338 assert (!(obj->*index));
339 push_back (obj); 504 push_back (obj);
340 obj->*index = this->size ();
341 } 505 }
342 506
343 void insert (T &obj) 507 void insert (T &obj)
344 { 508 {
345 insert (&obj); 509 insert (&obj);
346 } 510 }
347 511
348 void erase (T *obj) 512 void erase (T *obj)
349 { 513 {
350 assert (obj->*index);
351 int pos = obj->*index; 514 unsigned int pos = obj->*indexmember;
352 obj->*index = 0; 515 obj->*indexmember = 0;
353 516
354 if (pos < this->size ()) 517 if (pos < this->size ())
355 { 518 {
356 (*this)[pos - 1] = (*this)[this->size () - 1]; 519 (*this)[pos - 1] = (*this)[this->size () - 1];
357 (*this)[pos - 1]->*index = pos; 520 (*this)[pos - 1]->*indexmember = pos;
358 } 521 }
359 522
360 this->pop_back (); 523 this->pop_back ();
361 } 524 }
362 525
363 void erase (T &obj) 526 void erase (T &obj)
364 { 527 {
365 errase (&obj); 528 erase (&obj);
366 } 529 }
367}; 530};
368 531
369// basically does what strncpy should do, but appends "..." to strings exceeding length 532// basically does what strncpy should do, but appends "..." to strings exceeding length
370void assign (char *dst, const char *src, int maxlen); 533void assign (char *dst, const char *src, int maxlen);
… …
381// return current time as timestampe 544// return current time as timestampe
382tstamp now (); 545tstamp now ();
383 546
384int similar_direction (int a, int b); 547int similar_direction (int a, int b);
385 548
549// like sprintf, but returns a "static" buffer
550const char *format (const char *format, ...);
551
386#endif 552#endif
387 553

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