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Comparing deliantra/server/include/util.h (file contents):
Revision 1.28 by root, Mon Jan 15 01:25:41 2007 UTC vs.
Revision 1.37 by root, Thu Feb 15 15:43:36 2007 UTC

1#ifndef UTIL_H__ 1#ifndef UTIL_H__
2#define UTIL_H__ 2#define UTIL_H__
3
4//#define PREFER_MALLOC
3 5
4#if __GNUC__ >= 3 6#if __GNUC__ >= 3
5# define is_constant(c) __builtin_constant_p (c) 7# define is_constant(c) __builtin_constant_p (c)
6#else 8#else
7# define is_constant(c) 0 9# define is_constant(c) 0
… …
32 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg)) 34 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
33 35
34// in range excluding end 36// in range excluding end
35#define IN_RANGE_EXC(val,beg,end) \ 37#define IN_RANGE_EXC(val,beg,end) \
36 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg)) 38 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
39
40void fork_abort (const char *msg);
41
42// rationale for using (U) not (T) is to reduce signed/unsigned issues,
43// as a is often a constant while b is the variable. it is still a bug, though.
44template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
45template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
46template<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; }
47
48template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
49
50// lots of stuff taken from FXT
51
52/* Rotate right. This is used in various places for checksumming */
53//TODO: this sucks, use a better checksum algo
54static inline uint32_t
55rotate_right (uint32_t c)
56{
57 return (c << 31) | (c >> 1);
58}
59
60// Return abs(a-b)
61// Both a and b must not have the most significant bit set
62static inline uint32_t
63upos_abs_diff (uint32_t a, uint32_t b)
64{
65 long d1 = b - a;
66 long d2 = (d1 & (d1 >> 31)) << 1;
67
68 return d1 - d2; // == (b - d) - (a + d);
69}
70
71// Both a and b must not have the most significant bit set
72static inline uint32_t
73upos_min (uint32_t a, uint32_t b)
74{
75 int32_t d = b - a;
76 d &= d >> 31;
77 return a + d;
78}
79
80// Both a and b must not have the most significant bit set
81static inline uint32_t
82upos_max (uint32_t a, uint32_t b)
83{
84 int32_t d = b - a;
85 d &= d >> 31;
86 return b - d;
87}
37 88
38// this is much faster than crossfires original algorithm 89// this is much faster than crossfires original algorithm
39// on modern cpus 90// on modern cpus
40inline int 91inline int
41isqrt (int n) 92isqrt (int n)
… …
58#if 0 109#if 0
59 return dx_ > dy_ 110 return dx_ > dy_
60 ? (dx_ * 61685 + dy_ * 26870) >> 16 111 ? (dx_ * 61685 + dy_ * 26870) >> 16
61 : (dy_ * 61685 + dx_ * 26870) >> 16; 112 : (dy_ * 61685 + dx_ * 26870) >> 16;
62#else 113#else
63 return dx + dy - min (dx, dy) * 5 / 8; 114 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
64#endif 115#endif
65} 116}
66 117
118/*
119 * absdir(int): Returns a number between 1 and 8, which represent
120 * the "absolute" direction of a number (it actually takes care of
121 * "overflow" in previous calculations of a direction).
122 */
123inline int
124absdir (int d)
125{
126 return ((d - 1) & 7) + 1;
127}
67 128
68// makes dynamically allocated objects zero-initialised 129// makes dynamically allocated objects zero-initialised
69struct zero_initialised 130struct zero_initialised
70{ 131{
71 void *operator new (size_t s, void *p) 132 void *operator new (size_t s, void *p)
… …
113 174
114// for symmetry 175// for symmetry
115template<typename T> 176template<typename T>
116inline void sfree (T *ptr, int n = 1) throw () 177inline void sfree (T *ptr, int n = 1) throw ()
117{ 178{
179#ifdef PREFER_MALLOC
180 free (ptr);
181#else
118 g_slice_free1 (n * sizeof (T), (void *)ptr); 182 g_slice_free1 (n * sizeof (T), (void *)ptr);
183#endif
119} 184}
120 185
121// a STL-compatible allocator that uses g_slice 186// a STL-compatible allocator that uses g_slice
122// boy, this is verbose 187// boy, this is verbose
123template<typename Tp> 188template<typename Tp>
… …
170 void destroy (pointer p) 235 void destroy (pointer p)
171 { 236 {
172 p->~Tp (); 237 p->~Tp ();
173 } 238 }
174}; 239};
240
241// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
242// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
243// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
244struct tausworthe_random_generator
245{
246 // generator
247 uint32_t state [4];
248
249 void operator =(const tausworthe_random_generator &src)
250 {
251 state [0] = src.state [0];
252 state [1] = src.state [1];
253 state [2] = src.state [2];
254 state [3] = src.state [3];
255 }
256
257 void seed (uint32_t seed);
258 uint32_t next ();
259
260 // uniform distribution
261 uint32_t operator ()(uint32_t r_max)
262 {
263 return is_constant (r_max)
264 ? this->next () % r_max
265 : get_range (r_max);
266 }
267
268 // return a number within (min .. max)
269 int operator () (int r_min, int r_max)
270 {
271 return is_constant (r_min) && is_constant (r_max)
272 ? r_min + (*this) (max (r_max - r_min + 1, 1))
273 : get_range (r_min, r_max);
274 }
275
276 double operator ()()
277 {
278 return this->next () / (double)0xFFFFFFFFU;
279 }
280
281protected:
282 uint32_t get_range (uint32_t r_max);
283 int get_range (int r_min, int r_max);
284};
285
286typedef tausworthe_random_generator rand_gen;
287
288extern rand_gen rndm;
175 289
176template<class T> 290template<class T>
177struct refptr 291struct refptr
178{ 292{
179 T *p; 293 T *p;
… …
297 { 411 {
298 errase (&obj); 412 errase (&obj);
299 } 413 }
300}; 414};
301 415
302template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
303template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
304template<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; }
305
306template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
307
308// basically does what strncpy should do, but appends "..." to strings exceeding length 416// basically does what strncpy should do, but appends "..." to strings exceeding length
309void assign (char *dst, const char *src, int maxlen); 417void assign (char *dst, const char *src, int maxlen);
310 418
311// type-safe version of assign 419// type-safe version of assign
312template<int N> 420template<int N>

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