ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/deliantra/server/include/util.h
(Generate patch)

Comparing deliantra/server/include/util.h (file contents):
Revision 1.29 by root, Mon Jan 15 01:39:42 2007 UTC vs.
Revision 1.38 by root, Thu Feb 15 18:09:34 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: that sucks, use a better checksum algo
54static inline uint32_t
55rotate_right (uint32_t c, uint32_t count = 1)
56{
57 return (c << (32 - count)) | (c >> count);
58}
59
60static inline uint32_t
61rotate_left (uint32_t c, uint32_t count = 1)
62{
63 return (c >> (32 - count)) | (c << count);
64}
65
66// Return abs(a-b)
67// Both a and b must not have the most significant bit set
68static inline uint32_t
69upos_abs_diff (uint32_t a, uint32_t b)
70{
71 long d1 = b - a;
72 long d2 = (d1 & (d1 >> 31)) << 1;
73
74 return d1 - d2; // == (b - d) - (a + d);
75}
76
77// Both a and b must not have the most significant bit set
78static inline uint32_t
79upos_min (uint32_t a, uint32_t b)
80{
81 int32_t d = b - a;
82 d &= d >> 31;
83 return a + d;
84}
85
86// Both a and b must not have the most significant bit set
87static inline uint32_t
88upos_max (uint32_t a, uint32_t b)
89{
90 int32_t d = b - a;
91 d &= d >> 31;
92 return b - d;
93}
37 94
38// this is much faster than crossfires original algorithm 95// this is much faster than crossfires original algorithm
39// on modern cpus 96// on modern cpus
40inline int 97inline int
41isqrt (int n) 98isqrt (int n)
… …
58#if 0 115#if 0
59 return dx_ > dy_ 116 return dx_ > dy_
60 ? (dx_ * 61685 + dy_ * 26870) >> 16 117 ? (dx_ * 61685 + dy_ * 26870) >> 16
61 : (dy_ * 61685 + dx_ * 26870) >> 16; 118 : (dy_ * 61685 + dx_ * 26870) >> 16;
62#else 119#else
63 return dx + dy - min (dx, dy) * 5 / 8; 120 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
64#endif 121#endif
65} 122}
66 123
67/* 124/*
68 * absdir(int): Returns a number between 1 and 8, which represent 125 * absdir(int): Returns a number between 1 and 8, which represent
… …
123 180
124// for symmetry 181// for symmetry
125template<typename T> 182template<typename T>
126inline void sfree (T *ptr, int n = 1) throw () 183inline void sfree (T *ptr, int n = 1) throw ()
127{ 184{
185#ifdef PREFER_MALLOC
186 free (ptr);
187#else
128 g_slice_free1 (n * sizeof (T), (void *)ptr); 188 g_slice_free1 (n * sizeof (T), (void *)ptr);
189#endif
129} 190}
130 191
131// a STL-compatible allocator that uses g_slice 192// a STL-compatible allocator that uses g_slice
132// boy, this is verbose 193// boy, this is verbose
133template<typename Tp> 194template<typename Tp>
… …
180 void destroy (pointer p) 241 void destroy (pointer p)
181 { 242 {
182 p->~Tp (); 243 p->~Tp ();
183 } 244 }
184}; 245};
246
247// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
248// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
249// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
250struct tausworthe_random_generator
251{
252 // generator
253 uint32_t state [4];
254
255 void operator =(const tausworthe_random_generator &src)
256 {
257 state [0] = src.state [0];
258 state [1] = src.state [1];
259 state [2] = src.state [2];
260 state [3] = src.state [3];
261 }
262
263 void seed (uint32_t seed);
264 uint32_t next ();
265
266 // uniform distribution
267 uint32_t operator ()(uint32_t r_max)
268 {
269 return is_constant (r_max)
270 ? this->next () % r_max
271 : get_range (r_max);
272 }
273
274 // return a number within (min .. max)
275 int operator () (int r_min, int r_max)
276 {
277 return is_constant (r_min) && is_constant (r_max)
278 ? r_min + (*this) (max (r_max - r_min + 1, 1))
279 : get_range (r_min, r_max);
280 }
281
282 double operator ()()
283 {
284 return this->next () / (double)0xFFFFFFFFU;
285 }
286
287protected:
288 uint32_t get_range (uint32_t r_max);
289 int get_range (int r_min, int r_max);
290};
291
292typedef tausworthe_random_generator rand_gen;
293
294extern rand_gen rndm;
185 295
186template<class T> 296template<class T>
187struct refptr 297struct refptr
188{ 298{
189 T *p; 299 T *p;
… …
307 { 417 {
308 errase (&obj); 418 errase (&obj);
309 } 419 }
310}; 420};
311 421
312template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
313template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
314template<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; }
315
316template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
317
318// basically does what strncpy should do, but appends "..." to strings exceeding length 422// basically does what strncpy should do, but appends "..." to strings exceeding length
319void assign (char *dst, const char *src, int maxlen); 423void assign (char *dst, const char *src, int maxlen);
320 424
321// type-safe version of assign 425// type-safe version of assign
322template<int N> 426template<int N>

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines