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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 1.87 by root, Mon Jan 12 03:40:21 2009 UTC

1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2005,2006,2007,2008 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
1#ifndef UTIL_H__ 22#ifndef UTIL_H__
2#define UTIL_H__ 23#define UTIL_H__
3 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
4#if __GNUC__ >= 3 29#if __GNUC__ >= 3
5# define is_constant(c) __builtin_constant_p (c) 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# define noinline __attribute__((__noinline__))
6#else 34#else
7# define is_constant(c) 0 35# define is_constant(c) 0
36# define expect(expr,value) (expr)
37# define prefetch(addr,rw,locality)
38# define noinline
8#endif 39#endif
40
41#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
42# define decltype(x) typeof(x)
43#endif
44
45// put into ifs if you are very sure that the expression
46// is mostly true or mosty false. note that these return
47// booleans, not the expression.
48#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
49#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
50
51#include <pthread.h>
52
53#include <cstddef>
54#include <cmath>
55#include <new>
56#include <vector>
57
58#include <glib.h>
59
60#include <shstr.h>
61#include <traits.h>
62
63#if DEBUG_SALLOC
64# define g_slice_alloc0(s) debug_slice_alloc0(s)
65# define g_slice_alloc(s) debug_slice_alloc(s)
66# define g_slice_free1(s,p) debug_slice_free1(s,p)
67void *g_slice_alloc (unsigned long size);
68void *g_slice_alloc0 (unsigned long size);
69void g_slice_free1 (unsigned long size, void *ptr);
70#elif PREFER_MALLOC
71# define g_slice_alloc0(s) calloc (1, (s))
72# define g_slice_alloc(s) malloc ((s))
73# define g_slice_free1(s,p) free ((p))
74#endif
75
76// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
77#define auto(var,expr) decltype(expr) var = (expr)
78
79// very ugly macro that basically declares and initialises a variable
80// that is in scope for the next statement only
81// works only for stuff that can be assigned 0 and converts to false
82// (note: works great for pointers)
83// most ugly macro I ever wrote
84#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
85
86// in range including end
87#define IN_RANGE_INC(val,beg,end) \
88 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
89
90// in range excluding end
91#define IN_RANGE_EXC(val,beg,end) \
92 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
93
94void cleanup (const char *cause, bool make_core = false);
95void fork_abort (const char *msg);
96
97// rationale for using (U) not (T) is to reduce signed/unsigned issues,
98// as a is often a constant while b is the variable. it is still a bug, though.
99template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
100template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
101template<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; }
102
103template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); }
104template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); }
105template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); }
106
107template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
108
109template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
110template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
111
112// sign returns -1 or +1
113template<typename T>
114static inline T sign (T v) { return v < 0 ? -1 : +1; }
115// relies on 2c representation
116template<>
117inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
118
119// sign0 returns -1, 0 or +1
120template<typename T>
121static inline T sign0 (T v) { return v ? sign (v) : 0; }
122
123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
124template<typename T> static inline T div (T val, T div) { return (val + div / 2) / div; }
125// div, round-up
126template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; }
127// div, round-down
128template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; }
129
130template<typename T>
131static inline T
132lerp (T val, T min_in, T max_in, T min_out, T max_out)
133{
134 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
135}
136
137// lerp, round-down
138template<typename T>
139static inline T
140lerp_rd (T val, T min_in, T max_in, T min_out, T max_out)
141{
142 return min_out + div_rd<T> ((val - min_in) * (max_out - min_out), max_in - min_in);
143}
144
145// lerp, round-up
146template<typename T>
147static inline T
148lerp_ru (T val, T min_in, T max_in, T min_out, T max_out)
149{
150 return min_out + div_ru<T> ((val - min_in) * (max_out - min_out), max_in - min_in);
151}
152
153// lots of stuff taken from FXT
154
155/* Rotate right. This is used in various places for checksumming */
156//TODO: that sucks, use a better checksum algo
157static inline uint32_t
158rotate_right (uint32_t c, uint32_t count = 1)
159{
160 return (c << (32 - count)) | (c >> count);
161}
162
163static inline uint32_t
164rotate_left (uint32_t c, uint32_t count = 1)
165{
166 return (c >> (32 - count)) | (c << count);
167}
168
169// Return abs(a-b)
170// Both a and b must not have the most significant bit set
171static inline uint32_t
172upos_abs_diff (uint32_t a, uint32_t b)
173{
174 long d1 = b - a;
175 long d2 = (d1 & (d1 >> 31)) << 1;
176
177 return d1 - d2; // == (b - d) - (a + d);
178}
179
180// Both a and b must not have the most significant bit set
181static inline uint32_t
182upos_min (uint32_t a, uint32_t b)
183{
184 int32_t d = b - a;
185 d &= d >> 31;
186 return a + d;
187}
188
189// Both a and b must not have the most significant bit set
190static inline uint32_t
191upos_max (uint32_t a, uint32_t b)
192{
193 int32_t d = b - a;
194 d &= d >> 31;
195 return b - d;
196}
197
198// this is much faster than crossfires original algorithm
199// on modern cpus
200inline int
201isqrt (int n)
202{
203 return (int)sqrtf ((float)n);
204}
205
206// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
207#if 0
208// and has a max. error of 6 in the range -100..+100.
209#else
210// and has a max. error of 9 in the range -100..+100.
211#endif
212inline int
213idistance (int dx, int dy)
214{
215 unsigned int dx_ = abs (dx);
216 unsigned int dy_ = abs (dy);
217
218#if 0
219 return dx_ > dy_
220 ? (dx_ * 61685 + dy_ * 26870) >> 16
221 : (dy_ * 61685 + dx_ * 26870) >> 16;
222#else
223 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
224#endif
225}
226
227/*
228 * absdir(int): Returns a number between 1 and 8, which represent
229 * the "absolute" direction of a number (it actually takes care of
230 * "overflow" in previous calculations of a direction).
231 */
232inline int
233absdir (int d)
234{
235 return ((d - 1) & 7) + 1;
236}
237
238extern ssize_t slice_alloc; // statistics
239
240void *salloc_ (int n) throw (std::bad_alloc);
241void *salloc_ (int n, void *src) throw (std::bad_alloc);
242
243// strictly the same as g_slice_alloc, but never returns 0
244template<typename T>
245inline T *salloc (int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T)); }
246
247// also copies src into the new area, like "memdup"
248// if src is 0, clears the memory
249template<typename T>
250inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
251
252// clears the memory
253template<typename T>
254inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); }
255
256// for symmetry
257template<typename T>
258inline void sfree (T *ptr, int n = 1) throw ()
259{
260 if (expect_true (ptr))
261 {
262 slice_alloc -= n * sizeof (T);
263 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
264 g_slice_free1 (n * sizeof (T), (void *)ptr);
265 assert (slice_alloc >= 0);//D
266 }
267}
268
269// nulls the pointer
270template<typename T>
271inline void sfree0 (T *&ptr, int n = 1) throw ()
272{
273 sfree<T> (ptr, n);
274 ptr = 0;
275}
9 276
10// makes dynamically allocated objects zero-initialised 277// makes dynamically allocated objects zero-initialised
11struct zero_initialised 278struct zero_initialised
12{ 279{
280 void *operator new (size_t s, void *p)
281 {
282 memset (p, 0, s);
283 return p;
284 }
285
13 void *operator new (size_t s); 286 void *operator new (size_t s)
287 {
288 return salloc0<char> (s);
289 }
290
14 void *operator new [] (size_t s); 291 void *operator new[] (size_t s)
292 {
293 return salloc0<char> (s);
294 }
295
15 void operator delete (void *p, size_t s); 296 void operator delete (void *p, size_t s)
297 {
298 sfree ((char *)p, s);
299 }
300
16 void operator delete [] (void *p, size_t s); 301 void operator delete[] (void *p, size_t s)
302 {
303 sfree ((char *)p, s);
304 }
17}; 305};
306
307// makes dynamically allocated objects zero-initialised
308struct slice_allocated
309{
310 void *operator new (size_t s, void *p)
311 {
312 return p;
313 }
314
315 void *operator new (size_t s)
316 {
317 return salloc<char> (s);
318 }
319
320 void *operator new[] (size_t s)
321 {
322 return salloc<char> (s);
323 }
324
325 void operator delete (void *p, size_t s)
326 {
327 sfree ((char *)p, s);
328 }
329
330 void operator delete[] (void *p, size_t s)
331 {
332 sfree ((char *)p, s);
333 }
334};
335
336// a STL-compatible allocator that uses g_slice
337// boy, this is verbose
338template<typename Tp>
339struct slice_allocator
340{
341 typedef size_t size_type;
342 typedef ptrdiff_t difference_type;
343 typedef Tp *pointer;
344 typedef const Tp *const_pointer;
345 typedef Tp &reference;
346 typedef const Tp &const_reference;
347 typedef Tp value_type;
348
349 template <class U>
350 struct rebind
351 {
352 typedef slice_allocator<U> other;
353 };
354
355 slice_allocator () throw () { }
356 slice_allocator (const slice_allocator &) throw () { }
357 template<typename Tp2>
358 slice_allocator (const slice_allocator<Tp2> &) throw () { }
359
360 ~slice_allocator () { }
361
362 pointer address (reference x) const { return &x; }
363 const_pointer address (const_reference x) const { return &x; }
364
365 pointer allocate (size_type n, const_pointer = 0)
366 {
367 return salloc<Tp> (n);
368 }
369
370 void deallocate (pointer p, size_type n)
371 {
372 sfree<Tp> (p, n);
373 }
374
375 size_type max_size () const throw ()
376 {
377 return size_t (-1) / sizeof (Tp);
378 }
379
380 void construct (pointer p, const Tp &val)
381 {
382 ::new (p) Tp (val);
383 }
384
385 void destroy (pointer p)
386 {
387 p->~Tp ();
388 }
389};
390
391// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
392// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
393// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
394struct tausworthe_random_generator
395{
396 uint32_t state [4];
397
398 void operator =(const tausworthe_random_generator &src)
399 {
400 state [0] = src.state [0];
401 state [1] = src.state [1];
402 state [2] = src.state [2];
403 state [3] = src.state [3];
404 }
405
406 void seed (uint32_t seed);
407 uint32_t next ();
408};
409
410// Xorshift RNGs, George Marsaglia
411// http://www.jstatsoft.org/v08/i14/paper
412// this one is about 40% faster than the tausworthe one above (i.e. not much),
413// despite the inlining, and has the issue of only creating 2**32-1 numbers.
414// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
415struct xorshift_random_generator
416{
417 uint32_t x, y;
418
419 void operator =(const xorshift_random_generator &src)
420 {
421 x = src.x;
422 y = src.y;
423 }
424
425 void seed (uint32_t seed)
426 {
427 x = seed;
428 y = seed * 69069U;
429 }
430
431 uint32_t next ()
432 {
433 uint32_t t = x ^ (x << 10);
434 x = y;
435 y = y ^ (y >> 13) ^ t ^ (t >> 10);
436 return y;
437 }
438};
439
440template<class generator>
441struct random_number_generator : generator
442{
443 // uniform distribution, 0 .. max (0, num - 1)
444 uint32_t operator ()(uint32_t num)
445 {
446 return !is_constant (num) ? get_range (num) // non-constant
447 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
448 : this->next () & (num - 1); // constant, power-of-two
449 }
450
451 // return a number within (min .. max)
452 int operator () (int r_min, int r_max)
453 {
454 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
455 ? r_min + operator ()(r_max - r_min + 1)
456 : get_range (r_min, r_max);
457 }
458
459 double operator ()()
460 {
461 return this->next () / (double)0xFFFFFFFFU;
462 }
463
464protected:
465 uint32_t get_range (uint32_t r_max);
466 int get_range (int r_min, int r_max);
467};
468
469typedef random_number_generator<tausworthe_random_generator> rand_gen;
470
471extern rand_gen rndm, rmg_rndm;
472
473INTERFACE_CLASS (attachable)
474struct refcnt_base
475{
476 typedef int refcnt_t;
477 mutable refcnt_t ACC (RW, refcnt);
478
479 MTH void refcnt_inc () const { ++refcnt; }
480 MTH void refcnt_dec () const { --refcnt; }
481
482 refcnt_base () : refcnt (0) { }
483};
484
485// to avoid branches with more advanced compilers
486extern refcnt_base::refcnt_t refcnt_dummy;
487
488template<class T>
489struct refptr
490{
491 // p if not null
492 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
493
494 void refcnt_dec ()
495 {
496 if (!is_constant (p))
497 --*refcnt_ref ();
498 else if (p)
499 --p->refcnt;
500 }
501
502 void refcnt_inc ()
503 {
504 if (!is_constant (p))
505 ++*refcnt_ref ();
506 else if (p)
507 ++p->refcnt;
508 }
509
510 T *p;
511
512 refptr () : p(0) { }
513 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
514 refptr (T *p) : p(p) { refcnt_inc (); }
515 ~refptr () { refcnt_dec (); }
516
517 const refptr<T> &operator =(T *o)
518 {
519 // if decrementing ever destroys we need to reverse the order here
520 refcnt_dec ();
521 p = o;
522 refcnt_inc ();
523 return *this;
524 }
525
526 const refptr<T> &operator =(const refptr<T> &o)
527 {
528 *this = o.p;
529 return *this;
530 }
531
532 T &operator * () const { return *p; }
533 T *operator ->() const { return p; }
534
535 operator T *() const { return p; }
536};
537
538typedef refptr<maptile> maptile_ptr;
539typedef refptr<object> object_ptr;
540typedef refptr<archetype> arch_ptr;
541typedef refptr<client> client_ptr;
542typedef refptr<player> player_ptr;
18 543
19struct str_hash 544struct str_hash
20{ 545{
21 std::size_t operator ()(const char *s) const 546 std::size_t operator ()(const char *s) const
22 { 547 {
23 unsigned long hash = 0; 548#if 0
549 uint32_t hash = 0;
24 550
25 /* use the one-at-a-time hash function, which supposedly is 551 /* use the one-at-a-time hash function, which supposedly is
26 * better than the djb2-like one used by perl5.005, but 552 * better than the djb2-like one used by perl5.005, but
27 * certainly is better then the bug used here before. 553 * certainly is better then the bug used here before.
28 * see http://burtleburtle.net/bob/hash/doobs.html 554 * see http://burtleburtle.net/bob/hash/doobs.html
… …
35 } 561 }
36 562
37 hash += hash << 3; 563 hash += hash << 3;
38 hash ^= hash >> 11; 564 hash ^= hash >> 11;
39 hash += hash << 15; 565 hash += hash << 15;
566#else
567 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
568 // it is about twice as fast as the one-at-a-time one,
569 // with good distribution.
570 // FNV-1a is faster on many cpus because the multiplication
571 // runs concurrent with the looping logic.
572 uint32_t hash = 2166136261;
573
574 while (*s)
575 hash = (hash ^ *s++) * 16777619;
576#endif
40 577
41 return hash; 578 return hash;
42 } 579 }
43}; 580};
44 581
… …
48 { 585 {
49 return !strcmp (a, b); 586 return !strcmp (a, b);
50 } 587 }
51}; 588};
52 589
590// Mostly the same as std::vector, but insert/erase can reorder
591// the elements, making append(=insert)/remove O(1) instead of O(n).
592//
593// NOTE: only some forms of erase are available
594template<class T>
595struct unordered_vector : std::vector<T, slice_allocator<T> >
596{
597 typedef typename unordered_vector::iterator iterator;
598
599 void erase (unsigned int pos)
600 {
601 if (pos < this->size () - 1)
602 (*this)[pos] = (*this)[this->size () - 1];
603
604 this->pop_back ();
605 }
606
607 void erase (iterator i)
608 {
609 erase ((unsigned int )(i - this->begin ()));
610 }
611};
612
613// This container blends advantages of linked lists
614// (efficiency) with vectors (random access) by
615// by using an unordered vector and storing the vector
616// index inside the object.
617//
618// + memory-efficient on most 64 bit archs
619// + O(1) insert/remove
620// + free unique (but varying) id for inserted objects
621// + cache-friendly iteration
622// - only works for pointers to structs
623//
624// NOTE: only some forms of erase/insert are available
625typedef int object_vector_index;
626
627template<class T, object_vector_index T::*indexmember>
628struct object_vector : std::vector<T *, slice_allocator<T *> >
629{
630 typedef typename object_vector::iterator iterator;
631
632 bool contains (const T *obj) const
633 {
634 return obj->*indexmember;
635 }
636
637 iterator find (const T *obj)
638 {
639 return obj->*indexmember
640 ? this->begin () + obj->*indexmember - 1
641 : this->end ();
642 }
643
644 void push_back (T *obj)
645 {
646 std::vector<T *, slice_allocator<T *> >::push_back (obj);
647 obj->*indexmember = this->size ();
648 }
649
650 void insert (T *obj)
651 {
652 push_back (obj);
653 }
654
655 void insert (T &obj)
656 {
657 insert (&obj);
658 }
659
660 void erase (T *obj)
661 {
662 unsigned int pos = obj->*indexmember;
663 obj->*indexmember = 0;
664
665 if (pos < this->size ())
666 {
667 (*this)[pos - 1] = (*this)[this->size () - 1];
668 (*this)[pos - 1]->*indexmember = pos;
669 }
670
671 this->pop_back ();
672 }
673
674 void erase (T &obj)
675 {
676 erase (&obj);
677 }
678};
679
680// basically does what strncpy should do, but appends "..." to strings exceeding length
681// returns the number of bytes actually used (including \0)
682int assign (char *dst, const char *src, int maxsize);
683
684// type-safe version of assign
685template<int N>
686inline int assign (char (&dst)[N], const char *src)
687{
688 return assign ((char *)&dst, src, N);
689}
690
691typedef double tstamp;
692
693// return current time as timestamp
694tstamp now ();
695
696int similar_direction (int a, int b);
697
698// like sprintf, but returns a "static" buffer
699const char *format (const char *format, ...);
700
701/////////////////////////////////////////////////////////////////////////////
702// threads, very very thin wrappers around pthreads
703
704struct thread
705{
706 pthread_t id;
707
708 void start (void *(*start_routine)(void *), void *arg = 0);
709
710 void cancel ()
711 {
712 pthread_cancel (id);
713 }
714
715 void *join ()
716 {
717 void *ret;
718
719 if (pthread_join (id, &ret))
720 cleanup ("pthread_join failed", 1);
721
722 return ret;
723 }
724};
725
726// note that mutexes are not classes
727typedef pthread_mutex_t smutex;
728
729#if __linux && defined (PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
730 #define SMUTEX_INITIALISER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
731#else
732 #define SMUTEX_INITIALISER PTHREAD_MUTEX_INITIALIZER
53#endif 733#endif
54 734
735#define SMUTEX(name) smutex name = SMUTEX_INITIALISER
736#define SMUTEX_LOCK(name) pthread_mutex_lock (&(name))
737#define SMUTEX_UNLOCK(name) pthread_mutex_unlock (&(name))
738
739typedef pthread_cond_t scond;
740
741#define SCOND(name) scond name = PTHREAD_COND_INITIALIZER
742#define SCOND_SIGNAL(name) pthread_cond_signal (&(name))
743#define SCOND_BROADCAST(name) pthread_cond_broadcast (&(name))
744#define SCOND_WAIT(name,mutex) pthread_cond_wait (&(name), &(mutex))
745
746#endif
747

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