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Comparing deliantra/server/include/util.h (file contents):
Revision 1.26 by root, Sun Jan 7 02:39:14 2007 UTC vs.
Revision 1.45 by root, Sat May 26 15:44:05 2007 UTC

1#ifndef UTIL_H__ 1#ifndef UTIL_H__
2#define UTIL_H__ 2#define UTIL_H__
3 3
4//#define PREFER_MALLOC
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)
8# define expect(expr,value) __builtin_expect ((expr),(value))
9# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
6#else 10#else
7# define is_constant(c) 0 11# define is_constant(c) 0
12# define expect(expr,value) (expr)
13# define prefetch(addr,rw,locality)
8#endif 14#endif
9 15
16// put into ifs if you are very sure that the expression
17// is mostly true or mosty false. note that these return
18// booleans, not the expression.
19#define expect_false(expr) expect ((expr) != 0, 0)
20#define expect_true(expr) expect ((expr) != 0, 1)
21
10#include <cstddef> 22#include <cstddef>
23#include <cmath>
11#include <new> 24#include <new>
12#include <vector> 25#include <vector>
13 26
14#include <glib.h> 27#include <glib.h>
15 28
16#include <shstr.h> 29#include <shstr.h>
17#include <traits.h> 30#include <traits.h>
18 31
19// use a gcc extension for auto declarations until ISO C++ sanctifies them 32// use a gcc extension for auto declarations until ISO C++ sanctifies them
20#define AUTODECL(var,expr) typeof(expr) var = (expr) 33#define auto(var,expr) typeof(expr) var = (expr)
21 34
22// very ugly macro that basicaly declares and initialises a variable 35// very ugly macro that basicaly declares and initialises a variable
23// that is in scope for the next statement only 36// that is in scope for the next statement only
24// works only for stuff that can be assigned 0 and converts to false 37// works only for stuff that can be assigned 0 and converts to false
25// (note: works great for pointers) 38// (note: works great for pointers)
26// most ugly macro I ever wrote 39// most ugly macro I ever wrote
27#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 40#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
28 41
42// in range including end
43#define IN_RANGE_INC(val,beg,end) \
44 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
45
46// in range excluding end
47#define IN_RANGE_EXC(val,beg,end) \
48 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
49
50void fork_abort (const char *msg);
51
52// rationale for using (U) not (T) is to reduce signed/unsigned issues,
53// as a is often a constant while b is the variable. it is still a bug, though.
54template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
55template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
56template<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; }
57
58template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
59
60template<typename T>
61static inline T
62lerp (T val, T min_in, T max_in, T min_out, T max_out)
63{
64 return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
65}
66
67// lots of stuff taken from FXT
68
69/* Rotate right. This is used in various places for checksumming */
70//TODO: that sucks, use a better checksum algo
71static inline uint32_t
72rotate_right (uint32_t c, uint32_t count = 1)
73{
74 return (c << (32 - count)) | (c >> count);
75}
76
77static inline uint32_t
78rotate_left (uint32_t c, uint32_t count = 1)
79{
80 return (c >> (32 - count)) | (c << count);
81}
82
83// Return abs(a-b)
84// Both a and b must not have the most significant bit set
85static inline uint32_t
86upos_abs_diff (uint32_t a, uint32_t b)
87{
88 long d1 = b - a;
89 long d2 = (d1 & (d1 >> 31)) << 1;
90
91 return d1 - d2; // == (b - d) - (a + d);
92}
93
94// Both a and b must not have the most significant bit set
95static inline uint32_t
96upos_min (uint32_t a, uint32_t b)
97{
98 int32_t d = b - a;
99 d &= d >> 31;
100 return a + d;
101}
102
103// Both a and b must not have the most significant bit set
104static inline uint32_t
105upos_max (uint32_t a, uint32_t b)
106{
107 int32_t d = b - a;
108 d &= d >> 31;
109 return b - d;
110}
111
112// this is much faster than crossfires original algorithm
113// on modern cpus
114inline int
115isqrt (int n)
116{
117 return (int)sqrtf ((float)n);
118}
119
120// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
121#if 0
122// and has a max. error of 6 in the range -100..+100.
123#else
124// and has a max. error of 9 in the range -100..+100.
125#endif
126inline int
127idistance (int dx, int dy)
128{
129 unsigned int dx_ = abs (dx);
130 unsigned int dy_ = abs (dy);
131
132#if 0
133 return dx_ > dy_
134 ? (dx_ * 61685 + dy_ * 26870) >> 16
135 : (dy_ * 61685 + dx_ * 26870) >> 16;
136#else
137 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
138#endif
139}
140
141/*
142 * absdir(int): Returns a number between 1 and 8, which represent
143 * the "absolute" direction of a number (it actually takes care of
144 * "overflow" in previous calculations of a direction).
145 */
146inline int
147absdir (int d)
148{
149 return ((d - 1) & 7) + 1;
150}
151
29// makes dynamically allocated objects zero-initialised 152// makes dynamically allocated objects zero-initialised
30struct zero_initialised 153struct zero_initialised
31{ 154{
32 void *operator new (size_t s, void *p) 155 void *operator new (size_t s, void *p)
33 { 156 {
… …
74 197
75// for symmetry 198// for symmetry
76template<typename T> 199template<typename T>
77inline void sfree (T *ptr, int n = 1) throw () 200inline void sfree (T *ptr, int n = 1) throw ()
78{ 201{
202#ifdef PREFER_MALLOC
203 free (ptr);
204#else
79 g_slice_free1 (n * sizeof (T), (void *)ptr); 205 g_slice_free1 (n * sizeof (T), (void *)ptr);
206#endif
80} 207}
81 208
82// a STL-compatible allocator that uses g_slice 209// a STL-compatible allocator that uses g_slice
83// boy, this is verbose 210// boy, this is verbose
84template<typename Tp> 211template<typename Tp>
… …
131 void destroy (pointer p) 258 void destroy (pointer p)
132 { 259 {
133 p->~Tp (); 260 p->~Tp ();
134 } 261 }
135}; 262};
263
264// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
265// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
266// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
267struct tausworthe_random_generator
268{
269 // generator
270 uint32_t state [4];
271
272 void operator =(const tausworthe_random_generator &src)
273 {
274 state [0] = src.state [0];
275 state [1] = src.state [1];
276 state [2] = src.state [2];
277 state [3] = src.state [3];
278 }
279
280 void seed (uint32_t seed);
281 uint32_t next ();
282
283 // uniform distribution
284 uint32_t operator ()(uint32_t num)
285 {
286 return is_constant (num)
287 ? (next () * (uint64_t)num) >> 32U
288 : get_range (num);
289 }
290
291 // return a number within (min .. max)
292 int operator () (int r_min, int r_max)
293 {
294 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
295 ? r_min + operator ()(r_max - r_min + 1)
296 : get_range (r_min, r_max);
297 }
298
299 double operator ()()
300 {
301 return this->next () / (double)0xFFFFFFFFU;
302 }
303
304protected:
305 uint32_t get_range (uint32_t r_max);
306 int get_range (int r_min, int r_max);
307};
308
309typedef tausworthe_random_generator rand_gen;
310
311extern rand_gen rndm;
136 312
137template<class T> 313template<class T>
138struct refptr 314struct refptr
139{ 315{
140 T *p; 316 T *p;
… …
240 } 416 }
241 417
242 void erase (T *obj) 418 void erase (T *obj)
243 { 419 {
244 assert (obj->*index); 420 assert (obj->*index);
245 int pos = obj->*index; 421 unsigned int pos = obj->*index;
246 obj->*index = 0; 422 obj->*index = 0;
247 423
248 if (pos < this->size ()) 424 if (pos < this->size ())
249 { 425 {
250 (*this)[pos - 1] = (*this)[this->size () - 1]; 426 (*this)[pos - 1] = (*this)[this->size () - 1];
… …
258 { 434 {
259 errase (&obj); 435 errase (&obj);
260 } 436 }
261}; 437};
262 438
263template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
264template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
265template<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; }
266
267template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
268
269// basically does what strncpy should do, but appends "..." to strings exceeding length 439// basically does what strncpy should do, but appends "..." to strings exceeding length
270void assign (char *dst, const char *src, int maxlen); 440void assign (char *dst, const char *src, int maxlen);
271 441
272// type-safe version of assign 442// type-safe version of assign
273template<int N> 443template<int N>
… …
281// return current time as timestampe 451// return current time as timestampe
282tstamp now (); 452tstamp now ();
283 453
284int similar_direction (int a, int b); 454int similar_direction (int a, int b);
285 455
456// like printf, but returns a std::string
457const std::string format (const char *format, ...);
458
286#endif 459#endif
287 460

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