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Comparing deliantra/server/include/util.h (file contents):
Revision 1.32 by root, Thu Jan 18 19:32:37 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
… …
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))
37 39
38void fork_abort (const char *msg); 40void fork_abort (const char *msg);
39 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.
40template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; } 44template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
41template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; } 45template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
42template<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; } 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; }
43 47
44template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } 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}
45 88
46// this is much faster than crossfires original algorithm 89// this is much faster than crossfires original algorithm
47// on modern cpus 90// on modern cpus
48inline int 91inline int
49isqrt (int n) 92isqrt (int n)
… …
131 174
132// for symmetry 175// for symmetry
133template<typename T> 176template<typename T>
134inline void sfree (T *ptr, int n = 1) throw () 177inline void sfree (T *ptr, int n = 1) throw ()
135{ 178{
179#ifdef PREFER_MALLOC
180 free (ptr);
181#else
136 g_slice_free1 (n * sizeof (T), (void *)ptr); 182 g_slice_free1 (n * sizeof (T), (void *)ptr);
183#endif
137} 184}
138 185
139// a STL-compatible allocator that uses g_slice 186// a STL-compatible allocator that uses g_slice
140// boy, this is verbose 187// boy, this is verbose
141template<typename Tp> 188template<typename Tp>
… …
194// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 241// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
195// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 242// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
196// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps 243// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
197struct tausworthe_random_generator 244struct tausworthe_random_generator
198{ 245{
246 // generator
199 uint32_t state [4]; 247 uint32_t state [4];
200 248
201 tausworthe_random_generator (uint32_t seed); 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);
202 uint32_t next (); 258 uint32_t next ();
203 259
260 // uniform distribution
204 uint32_t operator ()(uint32_t r_max) 261 uint32_t operator ()(uint32_t r_max)
205 { 262 {
206 return next () % r_max; 263 return is_constant (r_max)
264 ? this->next () % r_max
265 : get_range (r_max);
207 } 266 }
208 267
209 // return a number within (min .. max) 268 // return a number within (min .. max)
210 int operator () (int r_min, int r_max) 269 int operator () (int r_min, int r_max)
211 { 270 {
212 return r_min + next () % max (r_max - r_min + 1, 1); 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);
213 } 274 }
214 275
215 double operator ()() 276 double operator ()()
216 { 277 {
217 return next () / (double)0xFFFFFFFFU; 278 return this->next () / (double)0xFFFFFFFFU;
218 } 279 }
280
281protected:
282 uint32_t get_range (uint32_t r_max);
283 int get_range (int r_min, int r_max);
219}; 284};
220 285
221typedef tausworthe_random_generator rand_gen; 286typedef tausworthe_random_generator rand_gen;
222 287
223extern rand_gen rndm; 288extern rand_gen rndm;

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