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Revision: 1.63
Committed: Sat Mar 15 13:52:38 2008 UTC (16 years, 2 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.62: +3 -0 lines
Log Message:
more const correctness and 5.10 gartituous breakage, sigh

File Contents

# User Rev Content
1 root 1.46 /*
2 root 1.58 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 root 1.46 *
4 root 1.58 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 root 1.46 *
6 root 1.58 * Deliantra is free software: you can redistribute it and/or modify
7 root 1.51 * 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 root 1.46 *
11 root 1.51 * 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 root 1.46 *
16 root 1.51 * 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 root 1.46 *
19 root 1.58 * The authors can be reached via e-mail to <support@deliantra.net>
20 root 1.46 */
21    
22 root 1.1 #ifndef UTIL_H__
23     #define UTIL_H__
24    
25 root 1.36 //#define PREFER_MALLOC
26 root 1.62 #define DEBUG_SALLOC
27 root 1.36
28 root 1.2 #if __GNUC__ >= 3
29 root 1.45 # define is_constant(c) __builtin_constant_p (c)
30     # define expect(expr,value) __builtin_expect ((expr),(value))
31     # define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
32 root 1.2 #else
33 root 1.45 # define is_constant(c) 0
34     # define expect(expr,value) (expr)
35     # define prefetch(addr,rw,locality)
36 root 1.2 #endif
37    
38 root 1.47 #if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
39     # define decltype(x) typeof(x)
40     #endif
41    
42 root 1.45 // put into ifs if you are very sure that the expression
43     // is mostly true or mosty false. note that these return
44     // booleans, not the expression.
45     #define expect_false(expr) expect ((expr) != 0, 0)
46     #define expect_true(expr) expect ((expr) != 0, 1)
47    
48 root 1.11 #include <cstddef>
49 root 1.28 #include <cmath>
50 root 1.25 #include <new>
51     #include <vector>
52 root 1.11
53     #include <glib.h>
54    
55 root 1.25 #include <shstr.h>
56     #include <traits.h>
57    
58 root 1.60 #ifdef DEBUG_SALLOC
59     # define g_slice_alloc0(s) debug_slice_alloc0(s)
60     # define g_slice_alloc(s) debug_slice_alloc(s)
61     # define g_slice_free1(s,p) debug_slice_free1(s,p)
62     void *g_slice_alloc (unsigned long size);
63     void *g_slice_alloc0 (unsigned long size);
64     void g_slice_free1 (unsigned long size, void *ptr);
65     #endif
66    
67 root 1.49 // use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
68 root 1.47 #define auto(var,expr) decltype(expr) var = (expr)
69 root 1.14
70 root 1.26 // very ugly macro that basicaly declares and initialises a variable
71     // that is in scope for the next statement only
72     // works only for stuff that can be assigned 0 and converts to false
73     // (note: works great for pointers)
74     // most ugly macro I ever wrote
75 root 1.48 #define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
76 root 1.26
77 root 1.27 // in range including end
78     #define IN_RANGE_INC(val,beg,end) \
79     ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
80    
81     // in range excluding end
82     #define IN_RANGE_EXC(val,beg,end) \
83     ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
84    
85 root 1.31 void fork_abort (const char *msg);
86    
87 root 1.35 // rationale for using (U) not (T) is to reduce signed/unsigned issues,
88     // as a is often a constant while b is the variable. it is still a bug, though.
89     template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
90     template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
91     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; }
92 root 1.32
93     template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
94    
95 root 1.63 template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
96     template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
97    
98 root 1.44 template<typename T>
99     static inline T
100     lerp (T val, T min_in, T max_in, T min_out, T max_out)
101     {
102     return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
103     }
104    
105 root 1.37 // lots of stuff taken from FXT
106    
107     /* Rotate right. This is used in various places for checksumming */
108 root 1.38 //TODO: that sucks, use a better checksum algo
109 root 1.37 static inline uint32_t
110 root 1.38 rotate_right (uint32_t c, uint32_t count = 1)
111 root 1.37 {
112 root 1.38 return (c << (32 - count)) | (c >> count);
113     }
114    
115     static inline uint32_t
116     rotate_left (uint32_t c, uint32_t count = 1)
117     {
118     return (c >> (32 - count)) | (c << count);
119 root 1.37 }
120    
121     // Return abs(a-b)
122     // Both a and b must not have the most significant bit set
123     static inline uint32_t
124     upos_abs_diff (uint32_t a, uint32_t b)
125     {
126     long d1 = b - a;
127     long d2 = (d1 & (d1 >> 31)) << 1;
128    
129     return d1 - d2; // == (b - d) - (a + d);
130     }
131    
132     // Both a and b must not have the most significant bit set
133     static inline uint32_t
134     upos_min (uint32_t a, uint32_t b)
135     {
136     int32_t d = b - a;
137     d &= d >> 31;
138     return a + d;
139     }
140    
141     // Both a and b must not have the most significant bit set
142     static inline uint32_t
143     upos_max (uint32_t a, uint32_t b)
144     {
145     int32_t d = b - a;
146     d &= d >> 31;
147     return b - d;
148     }
149    
150 root 1.28 // this is much faster than crossfires original algorithm
151     // on modern cpus
152     inline int
153     isqrt (int n)
154     {
155     return (int)sqrtf ((float)n);
156     }
157    
158     // this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
159     #if 0
160     // and has a max. error of 6 in the range -100..+100.
161     #else
162     // and has a max. error of 9 in the range -100..+100.
163     #endif
164     inline int
165     idistance (int dx, int dy)
166     {
167     unsigned int dx_ = abs (dx);
168     unsigned int dy_ = abs (dy);
169    
170     #if 0
171     return dx_ > dy_
172     ? (dx_ * 61685 + dy_ * 26870) >> 16
173     : (dy_ * 61685 + dx_ * 26870) >> 16;
174     #else
175 root 1.30 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
176 root 1.28 #endif
177     }
178    
179 root 1.29 /*
180     * absdir(int): Returns a number between 1 and 8, which represent
181     * the "absolute" direction of a number (it actually takes care of
182     * "overflow" in previous calculations of a direction).
183     */
184     inline int
185     absdir (int d)
186     {
187     return ((d - 1) & 7) + 1;
188     }
189 root 1.28
190 root 1.57 extern size_t slice_alloc; // statistics
191    
192 root 1.1 // makes dynamically allocated objects zero-initialised
193     struct zero_initialised
194     {
195 root 1.11 void *operator new (size_t s, void *p)
196     {
197     memset (p, 0, s);
198     return p;
199     }
200    
201     void *operator new (size_t s)
202     {
203 root 1.57 slice_alloc += s;
204 root 1.11 return g_slice_alloc0 (s);
205     }
206    
207     void *operator new[] (size_t s)
208     {
209 root 1.57 slice_alloc += s;
210 root 1.11 return g_slice_alloc0 (s);
211     }
212    
213     void operator delete (void *p, size_t s)
214     {
215 root 1.57 slice_alloc -= s;
216 root 1.11 g_slice_free1 (s, p);
217     }
218    
219     void operator delete[] (void *p, size_t s)
220     {
221 root 1.57 slice_alloc -= s;
222 root 1.11 g_slice_free1 (s, p);
223     }
224     };
225    
226 root 1.20 void *salloc_ (int n) throw (std::bad_alloc);
227     void *salloc_ (int n, void *src) throw (std::bad_alloc);
228    
229 root 1.12 // strictly the same as g_slice_alloc, but never returns 0
230 root 1.20 template<typename T>
231     inline T *salloc (int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T)); }
232    
233 root 1.17 // also copies src into the new area, like "memdup"
234 root 1.18 // if src is 0, clears the memory
235     template<typename T>
236 root 1.20 inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
237 root 1.18
238 root 1.21 // clears the memory
239     template<typename T>
240     inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); }
241    
242 root 1.12 // for symmetry
243 root 1.18 template<typename T>
244 root 1.20 inline void sfree (T *ptr, int n = 1) throw ()
245 root 1.12 {
246 root 1.36 #ifdef PREFER_MALLOC
247     free (ptr);
248     #else
249 root 1.57 slice_alloc -= n * sizeof (T);
250 root 1.20 g_slice_free1 (n * sizeof (T), (void *)ptr);
251 root 1.36 #endif
252 root 1.12 }
253 root 1.11
254     // a STL-compatible allocator that uses g_slice
255     // boy, this is verbose
256     template<typename Tp>
257     struct slice_allocator
258     {
259     typedef size_t size_type;
260     typedef ptrdiff_t difference_type;
261     typedef Tp *pointer;
262     typedef const Tp *const_pointer;
263     typedef Tp &reference;
264     typedef const Tp &const_reference;
265     typedef Tp value_type;
266    
267     template <class U>
268     struct rebind
269     {
270     typedef slice_allocator<U> other;
271     };
272    
273     slice_allocator () throw () { }
274     slice_allocator (const slice_allocator &o) throw () { }
275     template<typename Tp2>
276     slice_allocator (const slice_allocator<Tp2> &) throw () { }
277    
278     ~slice_allocator () { }
279    
280     pointer address (reference x) const { return &x; }
281     const_pointer address (const_reference x) const { return &x; }
282    
283     pointer allocate (size_type n, const_pointer = 0)
284     {
285 root 1.18 return salloc<Tp> (n);
286 root 1.11 }
287    
288     void deallocate (pointer p, size_type n)
289     {
290 root 1.19 sfree<Tp> (p, n);
291 root 1.11 }
292    
293     size_type max_size ()const throw ()
294     {
295     return size_t (-1) / sizeof (Tp);
296     }
297    
298     void construct (pointer p, const Tp &val)
299     {
300     ::new (p) Tp (val);
301     }
302    
303     void destroy (pointer p)
304     {
305     p->~Tp ();
306     }
307 root 1.1 };
308    
309 root 1.32 // P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
310     // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
311     // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
312     struct tausworthe_random_generator
313     {
314 root 1.34 // generator
315 root 1.32 uint32_t state [4];
316    
317 root 1.34 void operator =(const tausworthe_random_generator &src)
318     {
319     state [0] = src.state [0];
320     state [1] = src.state [1];
321     state [2] = src.state [2];
322     state [3] = src.state [3];
323     }
324    
325     void seed (uint32_t seed);
326 root 1.32 uint32_t next ();
327    
328 root 1.34 // uniform distribution
329 root 1.42 uint32_t operator ()(uint32_t num)
330 root 1.32 {
331 root 1.42 return is_constant (num)
332     ? (next () * (uint64_t)num) >> 32U
333     : get_range (num);
334 root 1.32 }
335    
336     // return a number within (min .. max)
337     int operator () (int r_min, int r_max)
338     {
339 root 1.42 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
340     ? r_min + operator ()(r_max - r_min + 1)
341 root 1.34 : get_range (r_min, r_max);
342 root 1.32 }
343    
344     double operator ()()
345     {
346 root 1.34 return this->next () / (double)0xFFFFFFFFU;
347 root 1.32 }
348 root 1.34
349     protected:
350     uint32_t get_range (uint32_t r_max);
351     int get_range (int r_min, int r_max);
352 root 1.32 };
353    
354     typedef tausworthe_random_generator rand_gen;
355    
356     extern rand_gen rndm;
357    
358 root 1.54 INTERFACE_CLASS (attachable)
359     struct refcnt_base
360     {
361     typedef int refcnt_t;
362     mutable refcnt_t ACC (RW, refcnt);
363    
364     MTH void refcnt_inc () const { ++refcnt; }
365     MTH void refcnt_dec () const { --refcnt; }
366    
367     refcnt_base () : refcnt (0) { }
368     };
369    
370 root 1.56 // to avoid branches with more advanced compilers
371 root 1.54 extern refcnt_base::refcnt_t refcnt_dummy;
372    
373 root 1.7 template<class T>
374     struct refptr
375     {
376 root 1.54 // p if not null
377     refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
378    
379     void refcnt_dec ()
380     {
381     if (!is_constant (p))
382     --*refcnt_ref ();
383     else if (p)
384     --p->refcnt;
385     }
386    
387     void refcnt_inc ()
388     {
389     if (!is_constant (p))
390     ++*refcnt_ref ();
391     else if (p)
392     ++p->refcnt;
393     }
394    
395 root 1.7 T *p;
396    
397     refptr () : p(0) { }
398 root 1.54 refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
399     refptr (T *p) : p(p) { refcnt_inc (); }
400     ~refptr () { refcnt_dec (); }
401 root 1.7
402     const refptr<T> &operator =(T *o)
403     {
404 root 1.54 // if decrementing ever destroys we need to reverse the order here
405     refcnt_dec ();
406 root 1.7 p = o;
407 root 1.54 refcnt_inc ();
408 root 1.7 return *this;
409     }
410    
411 root 1.54 const refptr<T> &operator =(const refptr<T> &o)
412 root 1.7 {
413     *this = o.p;
414     return *this;
415     }
416    
417     T &operator * () const { return *p; }
418 root 1.54 T *operator ->() const { return p; }
419 root 1.7
420     operator T *() const { return p; }
421     };
422    
423 root 1.24 typedef refptr<maptile> maptile_ptr;
424 root 1.22 typedef refptr<object> object_ptr;
425     typedef refptr<archetype> arch_ptr;
426 root 1.24 typedef refptr<client> client_ptr;
427     typedef refptr<player> player_ptr;
428 root 1.22
429 root 1.4 struct str_hash
430     {
431     std::size_t operator ()(const char *s) const
432     {
433     unsigned long hash = 0;
434    
435     /* use the one-at-a-time hash function, which supposedly is
436     * better than the djb2-like one used by perl5.005, but
437     * certainly is better then the bug used here before.
438     * see http://burtleburtle.net/bob/hash/doobs.html
439     */
440     while (*s)
441     {
442     hash += *s++;
443     hash += hash << 10;
444     hash ^= hash >> 6;
445     }
446    
447     hash += hash << 3;
448     hash ^= hash >> 11;
449     hash += hash << 15;
450    
451     return hash;
452     }
453     };
454    
455     struct str_equal
456     {
457     bool operator ()(const char *a, const char *b) const
458     {
459     return !strcmp (a, b);
460     }
461     };
462    
463 root 1.49 // Mostly the same as std::vector, but insert/erase can reorder
464 root 1.52 // the elements, making append(=insert)/remove O(1) instead of O(n).
465 root 1.49 //
466 root 1.52 // NOTE: only some forms of erase are available
467 root 1.26 template<class T>
468     struct unordered_vector : std::vector<T, slice_allocator<T> >
469 root 1.6 {
470 root 1.11 typedef typename unordered_vector::iterator iterator;
471 root 1.6
472     void erase (unsigned int pos)
473     {
474     if (pos < this->size () - 1)
475     (*this)[pos] = (*this)[this->size () - 1];
476    
477     this->pop_back ();
478     }
479    
480     void erase (iterator i)
481     {
482     erase ((unsigned int )(i - this->begin ()));
483     }
484     };
485    
486 root 1.49 // This container blends advantages of linked lists
487     // (efficiency) with vectors (random access) by
488     // by using an unordered vector and storing the vector
489     // index inside the object.
490     //
491     // + memory-efficient on most 64 bit archs
492     // + O(1) insert/remove
493     // + free unique (but varying) id for inserted objects
494     // + cache-friendly iteration
495     // - only works for pointers to structs
496     //
497     // NOTE: only some forms of erase/insert are available
498 root 1.50 typedef int object_vector_index;
499    
500     template<class T, object_vector_index T::*indexmember>
501 root 1.26 struct object_vector : std::vector<T *, slice_allocator<T *> >
502     {
503 root 1.48 typedef typename object_vector::iterator iterator;
504    
505     bool contains (const T *obj) const
506     {
507 root 1.50 return obj->*indexmember;
508 root 1.48 }
509    
510     iterator find (const T *obj)
511     {
512 root 1.50 return obj->*indexmember
513     ? this->begin () + obj->*indexmember - 1
514 root 1.48 : this->end ();
515     }
516    
517 root 1.53 void push_back (T *obj)
518     {
519     std::vector<T *, slice_allocator<T *> >::push_back (obj);
520     obj->*indexmember = this->size ();
521     }
522    
523 root 1.26 void insert (T *obj)
524     {
525     push_back (obj);
526     }
527    
528     void insert (T &obj)
529     {
530     insert (&obj);
531     }
532    
533     void erase (T *obj)
534     {
535 root 1.50 unsigned int pos = obj->*indexmember;
536     obj->*indexmember = 0;
537 root 1.26
538     if (pos < this->size ())
539     {
540     (*this)[pos - 1] = (*this)[this->size () - 1];
541 root 1.50 (*this)[pos - 1]->*indexmember = pos;
542 root 1.26 }
543    
544     this->pop_back ();
545     }
546    
547     void erase (T &obj)
548     {
549 root 1.50 erase (&obj);
550 root 1.26 }
551     };
552    
553 root 1.10 // basically does what strncpy should do, but appends "..." to strings exceeding length
554     void assign (char *dst, const char *src, int maxlen);
555    
556     // type-safe version of assign
557 root 1.9 template<int N>
558     inline void assign (char (&dst)[N], const char *src)
559     {
560 root 1.10 assign ((char *)&dst, src, N);
561 root 1.9 }
562    
563 root 1.17 typedef double tstamp;
564    
565 root 1.59 // return current time as timestamp
566 root 1.17 tstamp now ();
567    
568 root 1.25 int similar_direction (int a, int b);
569    
570 root 1.55 // like sprintf, but returns a "static" buffer
571     const char *format (const char *format, ...);
572 root 1.43
573 root 1.1 #endif
574