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Revision: 1.71
Committed: Sun Apr 20 06:20:38 2008 UTC (16 years, 1 month ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-2_52
Changes since 1.70: +1 -1 lines
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File Contents

# Content
1 /*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 *
6 * Deliantra 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 <support@deliantra.net>
20 */
21
22 #ifndef UTIL_H__
23 #define UTIL_H__
24
25 #define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26 #define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27 #define PREFER_MALLOC 0 // use malloc and not the slice allocator
28
29 #if __GNUC__ >= 3
30 # define is_constant(c) __builtin_constant_p (c)
31 # define expect(expr,value) __builtin_expect ((expr),(value))
32 # define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
33 #else
34 # define is_constant(c) 0
35 # define expect(expr,value) (expr)
36 # define prefetch(addr,rw,locality)
37 #endif
38
39 #if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
40 # define decltype(x) typeof(x)
41 #endif
42
43 // put into ifs if you are very sure that the expression
44 // is mostly true or mosty false. note that these return
45 // booleans, not the expression.
46 #define expect_false(expr) expect ((expr) != 0, 0)
47 #define expect_true(expr) expect ((expr) != 0, 1)
48
49 #include <pthread.h>
50
51 #include <cstddef>
52 #include <cmath>
53 #include <new>
54 #include <vector>
55
56 #include <glib.h>
57
58 #include <shstr.h>
59 #include <traits.h>
60
61 #if DEBUG_SALLOC
62 # define g_slice_alloc0(s) debug_slice_alloc0(s)
63 # define g_slice_alloc(s) debug_slice_alloc(s)
64 # define g_slice_free1(s,p) debug_slice_free1(s,p)
65 void *g_slice_alloc (unsigned long size);
66 void *g_slice_alloc0 (unsigned long size);
67 void g_slice_free1 (unsigned long size, void *ptr);
68 #elif PREFER_MALLOC
69 # define g_slice_alloc0(s) calloc (1, (s))
70 # define g_slice_alloc(s) malloc ((s))
71 # define g_slice_free1(s,p) free ((p))
72 #endif
73
74 // use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75 #define auto(var,expr) decltype(expr) var = (expr)
76
77 // very ugly macro that basicaly declares and initialises a variable
78 // that is in scope for the next statement only
79 // works only for stuff that can be assigned 0 and converts to false
80 // (note: works great for pointers)
81 // most ugly macro I ever wrote
82 #define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
83
84 // in range including end
85 #define IN_RANGE_INC(val,beg,end) \
86 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
87
88 // in range excluding end
89 #define IN_RANGE_EXC(val,beg,end) \
90 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
91
92 void cleanup (const char *cause, bool make_core = false);
93 void fork_abort (const char *msg);
94
95 // rationale for using (U) not (T) is to reduce signed/unsigned issues,
96 // as a is often a constant while b is the variable. it is still a bug, though.
97 template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
98 template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
99 template<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; }
100
101 template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
102
103 template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
104 template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
105
106 template<typename T>
107 static inline T
108 lerp (T val, T min_in, T max_in, T min_out, T max_out)
109 {
110 return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
111 }
112
113 // lots of stuff taken from FXT
114
115 /* Rotate right. This is used in various places for checksumming */
116 //TODO: that sucks, use a better checksum algo
117 static inline uint32_t
118 rotate_right (uint32_t c, uint32_t count = 1)
119 {
120 return (c << (32 - count)) | (c >> count);
121 }
122
123 static inline uint32_t
124 rotate_left (uint32_t c, uint32_t count = 1)
125 {
126 return (c >> (32 - count)) | (c << count);
127 }
128
129 // Return abs(a-b)
130 // Both a and b must not have the most significant bit set
131 static inline uint32_t
132 upos_abs_diff (uint32_t a, uint32_t b)
133 {
134 long d1 = b - a;
135 long d2 = (d1 & (d1 >> 31)) << 1;
136
137 return d1 - d2; // == (b - d) - (a + d);
138 }
139
140 // Both a and b must not have the most significant bit set
141 static inline uint32_t
142 upos_min (uint32_t a, uint32_t b)
143 {
144 int32_t d = b - a;
145 d &= d >> 31;
146 return a + d;
147 }
148
149 // Both a and b must not have the most significant bit set
150 static inline uint32_t
151 upos_max (uint32_t a, uint32_t b)
152 {
153 int32_t d = b - a;
154 d &= d >> 31;
155 return b - d;
156 }
157
158 // this is much faster than crossfires original algorithm
159 // on modern cpus
160 inline int
161 isqrt (int n)
162 {
163 return (int)sqrtf ((float)n);
164 }
165
166 // this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
167 #if 0
168 // and has a max. error of 6 in the range -100..+100.
169 #else
170 // and has a max. error of 9 in the range -100..+100.
171 #endif
172 inline int
173 idistance (int dx, int dy)
174 {
175 unsigned int dx_ = abs (dx);
176 unsigned int dy_ = abs (dy);
177
178 #if 0
179 return dx_ > dy_
180 ? (dx_ * 61685 + dy_ * 26870) >> 16
181 : (dy_ * 61685 + dx_ * 26870) >> 16;
182 #else
183 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
184 #endif
185 }
186
187 /*
188 * absdir(int): Returns a number between 1 and 8, which represent
189 * the "absolute" direction of a number (it actually takes care of
190 * "overflow" in previous calculations of a direction).
191 */
192 inline int
193 absdir (int d)
194 {
195 return ((d - 1) & 7) + 1;
196 }
197
198 extern ssize_t slice_alloc; // statistics
199
200 void *salloc_ (int n) throw (std::bad_alloc);
201 void *salloc_ (int n, void *src) throw (std::bad_alloc);
202
203 // strictly the same as g_slice_alloc, but never returns 0
204 template<typename T>
205 inline T *salloc (int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T)); }
206
207 // also copies src into the new area, like "memdup"
208 // if src is 0, clears the memory
209 template<typename T>
210 inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
211
212 // clears the memory
213 template<typename T>
214 inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); }
215
216 // for symmetry
217 template<typename T>
218 inline void sfree (T *ptr, int n = 1) throw ()
219 {
220 if (expect_true (ptr))
221 {
222 slice_alloc -= n * sizeof (T);
223 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
224 g_slice_free1 (n * sizeof (T), (void *)ptr);
225 assert (slice_alloc >= 0);//D
226 }
227 }
228
229 // makes dynamically allocated objects zero-initialised
230 struct zero_initialised
231 {
232 void *operator new (size_t s, void *p)
233 {
234 memset (p, 0, s);
235 return p;
236 }
237
238 void *operator new (size_t s)
239 {
240 return salloc0<char> (s);
241 }
242
243 void *operator new[] (size_t s)
244 {
245 return salloc0<char> (s);
246 }
247
248 void operator delete (void *p, size_t s)
249 {
250 sfree ((char *)p, s);
251 }
252
253 void operator delete[] (void *p, size_t s)
254 {
255 sfree ((char *)p, s);
256 }
257 };
258
259 // a STL-compatible allocator that uses g_slice
260 // boy, this is verbose
261 template<typename Tp>
262 struct slice_allocator
263 {
264 typedef size_t size_type;
265 typedef ptrdiff_t difference_type;
266 typedef Tp *pointer;
267 typedef const Tp *const_pointer;
268 typedef Tp &reference;
269 typedef const Tp &const_reference;
270 typedef Tp value_type;
271
272 template <class U>
273 struct rebind
274 {
275 typedef slice_allocator<U> other;
276 };
277
278 slice_allocator () throw () { }
279 slice_allocator (const slice_allocator &) throw () { }
280 template<typename Tp2>
281 slice_allocator (const slice_allocator<Tp2> &) throw () { }
282
283 ~slice_allocator () { }
284
285 pointer address (reference x) const { return &x; }
286 const_pointer address (const_reference x) const { return &x; }
287
288 pointer allocate (size_type n, const_pointer = 0)
289 {
290 return salloc<Tp> (n);
291 }
292
293 void deallocate (pointer p, size_type n)
294 {
295 sfree<Tp> (p, n);
296 }
297
298 size_type max_size () const throw ()
299 {
300 return size_t (-1) / sizeof (Tp);
301 }
302
303 void construct (pointer p, const Tp &val)
304 {
305 ::new (p) Tp (val);
306 }
307
308 void destroy (pointer p)
309 {
310 p->~Tp ();
311 }
312 };
313
314 // P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
315 // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
316 // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
317 struct tausworthe_random_generator
318 {
319 // generator
320 uint32_t state [4];
321
322 void operator =(const tausworthe_random_generator &src)
323 {
324 state [0] = src.state [0];
325 state [1] = src.state [1];
326 state [2] = src.state [2];
327 state [3] = src.state [3];
328 }
329
330 void seed (uint32_t seed);
331 uint32_t next ();
332
333 // uniform distribution
334 uint32_t operator ()(uint32_t num)
335 {
336 return is_constant (num)
337 ? (next () * (uint64_t)num) >> 32U
338 : get_range (num);
339 }
340
341 // return a number within (min .. max)
342 int operator () (int r_min, int r_max)
343 {
344 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
345 ? r_min + operator ()(r_max - r_min + 1)
346 : get_range (r_min, r_max);
347 }
348
349 double operator ()()
350 {
351 return this->next () / (double)0xFFFFFFFFU;
352 }
353
354 protected:
355 uint32_t get_range (uint32_t r_max);
356 int get_range (int r_min, int r_max);
357 };
358
359 typedef tausworthe_random_generator rand_gen;
360
361 extern rand_gen rndm;
362
363 INTERFACE_CLASS (attachable)
364 struct refcnt_base
365 {
366 typedef int refcnt_t;
367 mutable refcnt_t ACC (RW, refcnt);
368
369 MTH void refcnt_inc () const { ++refcnt; }
370 MTH void refcnt_dec () const { --refcnt; }
371
372 refcnt_base () : refcnt (0) { }
373 };
374
375 // to avoid branches with more advanced compilers
376 extern refcnt_base::refcnt_t refcnt_dummy;
377
378 template<class T>
379 struct refptr
380 {
381 // p if not null
382 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
383
384 void refcnt_dec ()
385 {
386 if (!is_constant (p))
387 --*refcnt_ref ();
388 else if (p)
389 --p->refcnt;
390 }
391
392 void refcnt_inc ()
393 {
394 if (!is_constant (p))
395 ++*refcnt_ref ();
396 else if (p)
397 ++p->refcnt;
398 }
399
400 T *p;
401
402 refptr () : p(0) { }
403 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
404 refptr (T *p) : p(p) { refcnt_inc (); }
405 ~refptr () { refcnt_dec (); }
406
407 const refptr<T> &operator =(T *o)
408 {
409 // if decrementing ever destroys we need to reverse the order here
410 refcnt_dec ();
411 p = o;
412 refcnt_inc ();
413 return *this;
414 }
415
416 const refptr<T> &operator =(const refptr<T> &o)
417 {
418 *this = o.p;
419 return *this;
420 }
421
422 T &operator * () const { return *p; }
423 T *operator ->() const { return p; }
424
425 operator T *() const { return p; }
426 };
427
428 typedef refptr<maptile> maptile_ptr;
429 typedef refptr<object> object_ptr;
430 typedef refptr<archetype> arch_ptr;
431 typedef refptr<client> client_ptr;
432 typedef refptr<player> player_ptr;
433
434 struct str_hash
435 {
436 std::size_t operator ()(const char *s) const
437 {
438 unsigned long hash = 0;
439
440 /* use the one-at-a-time hash function, which supposedly is
441 * better than the djb2-like one used by perl5.005, but
442 * certainly is better then the bug used here before.
443 * see http://burtleburtle.net/bob/hash/doobs.html
444 */
445 while (*s)
446 {
447 hash += *s++;
448 hash += hash << 10;
449 hash ^= hash >> 6;
450 }
451
452 hash += hash << 3;
453 hash ^= hash >> 11;
454 hash += hash << 15;
455
456 return hash;
457 }
458 };
459
460 struct str_equal
461 {
462 bool operator ()(const char *a, const char *b) const
463 {
464 return !strcmp (a, b);
465 }
466 };
467
468 // Mostly the same as std::vector, but insert/erase can reorder
469 // the elements, making append(=insert)/remove O(1) instead of O(n).
470 //
471 // NOTE: only some forms of erase are available
472 template<class T>
473 struct unordered_vector : std::vector<T, slice_allocator<T> >
474 {
475 typedef typename unordered_vector::iterator iterator;
476
477 void erase (unsigned int pos)
478 {
479 if (pos < this->size () - 1)
480 (*this)[pos] = (*this)[this->size () - 1];
481
482 this->pop_back ();
483 }
484
485 void erase (iterator i)
486 {
487 erase ((unsigned int )(i - this->begin ()));
488 }
489 };
490
491 // This container blends advantages of linked lists
492 // (efficiency) with vectors (random access) by
493 // by using an unordered vector and storing the vector
494 // index inside the object.
495 //
496 // + memory-efficient on most 64 bit archs
497 // + O(1) insert/remove
498 // + free unique (but varying) id for inserted objects
499 // + cache-friendly iteration
500 // - only works for pointers to structs
501 //
502 // NOTE: only some forms of erase/insert are available
503 typedef int object_vector_index;
504
505 template<class T, object_vector_index T::*indexmember>
506 struct object_vector : std::vector<T *, slice_allocator<T *> >
507 {
508 typedef typename object_vector::iterator iterator;
509
510 bool contains (const T *obj) const
511 {
512 return obj->*indexmember;
513 }
514
515 iterator find (const T *obj)
516 {
517 return obj->*indexmember
518 ? this->begin () + obj->*indexmember - 1
519 : this->end ();
520 }
521
522 void push_back (T *obj)
523 {
524 std::vector<T *, slice_allocator<T *> >::push_back (obj);
525 obj->*indexmember = this->size ();
526 }
527
528 void insert (T *obj)
529 {
530 push_back (obj);
531 }
532
533 void insert (T &obj)
534 {
535 insert (&obj);
536 }
537
538 void erase (T *obj)
539 {
540 unsigned int pos = obj->*indexmember;
541 obj->*indexmember = 0;
542
543 if (pos < this->size ())
544 {
545 (*this)[pos - 1] = (*this)[this->size () - 1];
546 (*this)[pos - 1]->*indexmember = pos;
547 }
548
549 this->pop_back ();
550 }
551
552 void erase (T &obj)
553 {
554 erase (&obj);
555 }
556 };
557
558 // basically does what strncpy should do, but appends "..." to strings exceeding length
559 void assign (char *dst, const char *src, int maxlen);
560
561 // type-safe version of assign
562 template<int N>
563 inline void assign (char (&dst)[N], const char *src)
564 {
565 assign ((char *)&dst, src, N);
566 }
567
568 typedef double tstamp;
569
570 // return current time as timestamp
571 tstamp now ();
572
573 int similar_direction (int a, int b);
574
575 // like sprintf, but returns a "static" buffer
576 const char *format (const char *format, ...);
577
578 /////////////////////////////////////////////////////////////////////////////
579 // threads, very very thin wrappers around pthreads
580
581 struct thread
582 {
583 pthread_t id;
584
585 void start (void *(*start_routine)(void *), void *arg = 0);
586
587 void cancel ()
588 {
589 pthread_cancel (id);
590 }
591
592 void *join ()
593 {
594 void *ret;
595
596 if (pthread_join (id, &ret))
597 cleanup ("pthread_join failed", 1);
598
599 return ret;
600 }
601 };
602
603 // note that mutexes are not classes
604 typedef pthread_mutex_t smutex;
605
606 #if __linux && defined (PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
607 #define SMUTEX_INITIALISER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
608 #else
609 #define SMUTEX_INITIALISER PTHREAD_MUTEX_INITIALIZER
610 #endif
611
612 #define SMUTEX(name) smutex name = SMUTEX_INITIALISER
613 #define SMUTEX_LOCK(name) pthread_mutex_lock (&(name))
614 #define SMUTEX_UNLOCK(name) pthread_mutex_unlock (&(name))
615
616 typedef pthread_cond_t scond;
617
618 #define SCOND(name) scond name = PTHREAD_COND_INITIALIZER
619 #define SCOND_SIGNAL(name) pthread_cond_signal (&(name))
620 #define SCOND_BROADCAST(name) pthread_cond_broadcast (&(name))
621 #define SCOND_WAIT(name,mutex) pthread_cond_wait (&(name), &(mutex))
622
623 #endif
624