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Comparing deliantra/server/include/util.h (file contents):
Revision 1.5 by pippijn, Thu Sep 7 20:03:20 2006 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)
46
47#include <cstddef>
48#include <cmath>
49#include <new>
50#include <vector>
51
52#include <glib.h>
53
54#include <shstr.h>
55#include <traits.h>
56
57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
58#define auto(var,expr) decltype(expr) var = (expr)
59
60// very ugly macro that basicaly declares and initialises a variable
61// that is in scope for the next statement only
62// works only for stuff that can be assigned 0 and converts to false
63// (note: works great for pointers)
64// most ugly macro I ever wrote
65#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
66
67// in range including end
68#define IN_RANGE_INC(val,beg,end) \
69 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
70
71// in range excluding end
72#define IN_RANGE_EXC(val,beg,end) \
73 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
74
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}
136
137// this is much faster than crossfires original algorithm
138// on modern cpus
139inline int
140isqrt (int n)
141{
142 return (int)sqrtf ((float)n);
143}
144
145// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
146#if 0
147// and has a max. error of 6 in the range -100..+100.
148#else
149// and has a max. error of 9 in the range -100..+100.
150#endif
151inline int
152idistance (int dx, int dy)
153{
154 unsigned int dx_ = abs (dx);
155 unsigned int dy_ = abs (dy);
156
157#if 0
158 return dx_ > dy_
159 ? (dx_ * 61685 + dy_ * 26870) >> 16
160 : (dy_ * 61685 + dx_ * 26870) >> 16;
161#else
162 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
163#endif
164}
165
166/*
167 * absdir(int): Returns a number between 1 and 8, which represent
168 * the "absolute" direction of a number (it actually takes care of
169 * "overflow" in previous calculations of a direction).
170 */
171inline int
172absdir (int d)
173{
174 return ((d - 1) & 7) + 1;
175}
9 176
10// makes dynamically allocated objects zero-initialised 177// makes dynamically allocated objects zero-initialised
11struct zero_initialised 178struct zero_initialised
12{ 179{
180 void *operator new (size_t s, void *p)
181 {
182 memset (p, 0, s);
183 return p;
184 }
185
13 void *operator new (size_t s); 186 void *operator new (size_t s)
187 {
188 return g_slice_alloc0 (s);
189 }
190
14 void *operator new [] (size_t s); 191 void *operator new[] (size_t s)
192 {
193 return g_slice_alloc0 (s);
194 }
195
15 void operator delete (void *p, size_t s); 196 void operator delete (void *p, size_t s)
197 {
198 g_slice_free1 (s, p);
199 }
200
16 void operator delete [] (void *p, size_t s); 201 void operator delete[] (void *p, size_t s)
202 {
203 g_slice_free1 (s, p);
204 }
17}; 205};
206
207void *salloc_ (int n) throw (std::bad_alloc);
208void *salloc_ (int n, void *src) throw (std::bad_alloc);
209
210// strictly the same as g_slice_alloc, but never returns 0
211template<typename T>
212inline T *salloc (int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T)); }
213
214// also copies src into the new area, like "memdup"
215// if src is 0, clears the memory
216template<typename T>
217inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
218
219// clears the memory
220template<typename T>
221inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); }
222
223// for symmetry
224template<typename T>
225inline void sfree (T *ptr, int n = 1) throw ()
226{
227#ifdef PREFER_MALLOC
228 free (ptr);
229#else
230 g_slice_free1 (n * sizeof (T), (void *)ptr);
231#endif
232}
233
234// a STL-compatible allocator that uses g_slice
235// boy, this is verbose
236template<typename Tp>
237struct slice_allocator
238{
239 typedef size_t size_type;
240 typedef ptrdiff_t difference_type;
241 typedef Tp *pointer;
242 typedef const Tp *const_pointer;
243 typedef Tp &reference;
244 typedef const Tp &const_reference;
245 typedef Tp value_type;
246
247 template <class U>
248 struct rebind
249 {
250 typedef slice_allocator<U> other;
251 };
252
253 slice_allocator () throw () { }
254 slice_allocator (const slice_allocator &o) throw () { }
255 template<typename Tp2>
256 slice_allocator (const slice_allocator<Tp2> &) throw () { }
257
258 ~slice_allocator () { }
259
260 pointer address (reference x) const { return &x; }
261 const_pointer address (const_reference x) const { return &x; }
262
263 pointer allocate (size_type n, const_pointer = 0)
264 {
265 return salloc<Tp> (n);
266 }
267
268 void deallocate (pointer p, size_type n)
269 {
270 sfree<Tp> (p, n);
271 }
272
273 size_type max_size ()const throw ()
274 {
275 return size_t (-1) / sizeof (Tp);
276 }
277
278 void construct (pointer p, const Tp &val)
279 {
280 ::new (p) Tp (val);
281 }
282
283 void destroy (pointer p)
284 {
285 p->~Tp ();
286 }
287};
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
350extern refcnt_base::refcnt_t refcnt_dummy;
351
352template<class T>
353struct refptr
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
374 T *p;
375
376 refptr () : p(0) { }
377 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
378 refptr (T *p) : p(p) { refcnt_inc (); }
379 ~refptr () { refcnt_dec (); }
380
381 const refptr<T> &operator =(T *o)
382 {
383 // if decrementing ever destroys we need to reverse the order here
384 refcnt_dec ();
385 p = o;
386 refcnt_inc ();
387 return *this;
388 }
389
390 const refptr<T> &operator =(const refptr<T> &o)
391 {
392 *this = o.p;
393 return *this;
394 }
395
396 T &operator * () const { return *p; }
397 T *operator ->() const { return p; }
398
399 operator T *() const { return p; }
400};
401
402typedef refptr<maptile> maptile_ptr;
403typedef refptr<object> object_ptr;
404typedef refptr<archetype> arch_ptr;
405typedef refptr<client> client_ptr;
406typedef refptr<player> player_ptr;
18 407
19struct str_hash 408struct str_hash
20{ 409{
21 std::size_t operator ()(const char *s) const 410 std::size_t operator ()(const char *s) const
22 { 411 {
48 { 437 {
49 return !strcmp (a, b); 438 return !strcmp (a, b);
50 } 439 }
51}; 440};
52 441
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
446template<class T>
447struct unordered_vector : std::vector<T, slice_allocator<T> >
448{
449 typedef typename unordered_vector::iterator iterator;
450
451 void erase (unsigned int pos)
452 {
453 if (pos < this->size () - 1)
454 (*this)[pos] = (*this)[this->size () - 1];
455
456 this->pop_back ();
457 }
458
459 void erase (iterator i)
460 {
461 erase ((unsigned int )(i - this->begin ()));
462 }
463};
464
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>
480struct object_vector : std::vector<T *, slice_allocator<T *> >
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
502 void insert (T *obj)
503 {
504 push_back (obj);
505 }
506
507 void insert (T &obj)
508 {
509 insert (&obj);
510 }
511
512 void erase (T *obj)
513 {
514 unsigned int pos = obj->*indexmember;
515 obj->*indexmember = 0;
516
517 if (pos < this->size ())
518 {
519 (*this)[pos - 1] = (*this)[this->size () - 1];
520 (*this)[pos - 1]->*indexmember = pos;
521 }
522
523 this->pop_back ();
524 }
525
526 void erase (T &obj)
527 {
528 erase (&obj);
529 }
530};
531
532// basically does what strncpy should do, but appends "..." to strings exceeding length
533void assign (char *dst, const char *src, int maxlen);
534
535// type-safe version of assign
536template<int N>
537inline void assign (char (&dst)[N], const char *src)
538{
539 assign ((char *)&dst, src, N);
540}
541
542typedef double tstamp;
543
544// return current time as timestampe
545tstamp now ();
546
547int similar_direction (int a, int b);
548
549// like sprintf, but returns a "static" buffer
550const char *format (const char *format, ...);
551
53#endif 552#endif
54 553

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