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Comparing deliantra/server/include/util.h (file contents):
Revision 1.78 by root, Thu Dec 4 03:48:19 2008 UTC vs.
Revision 1.89 by sf-marcmagus, Sun Oct 11 01:35:52 2009 UTC

… …
28 28
29#if __GNUC__ >= 3 29#if __GNUC__ >= 3
30# define is_constant(c) __builtin_constant_p (c) 30# define is_constant(c) __builtin_constant_p (c)
31# define expect(expr,value) __builtin_expect ((expr),(value)) 31# define expect(expr,value) __builtin_expect ((expr),(value))
32# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 32# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
33# define noinline __attribute__((__noinline__))
33#else 34#else
34# define is_constant(c) 0 35# define is_constant(c) 0
35# define expect(expr,value) (expr) 36# define expect(expr,value) (expr)
36# define prefetch(addr,rw,locality) 37# define prefetch(addr,rw,locality)
38# define noinline
37#endif 39#endif
38 40
39#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4) 41#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
40# define decltype(x) typeof(x) 42# define decltype(x) typeof(x)
41#endif 43#endif
42 44
43// put into ifs if you are very sure that the expression 45// put into ifs if you are very sure that the expression
44// is mostly true or mosty false. note that these return 46// is mostly true or mosty false. note that these return
45// booleans, not the expression. 47// booleans, not the expression.
46#define expect_false(expr) expect ((expr) != 0, 0) 48#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
47#define expect_true(expr) expect ((expr) != 0, 1) 49#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
48 50
49#include <pthread.h> 51#include <pthread.h>
50 52
51#include <cstddef> 53#include <cstddef>
52#include <cmath> 54#include <cmath>
… …
72#endif 74#endif
73 75
74// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) 76// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75#define auto(var,expr) decltype(expr) var = (expr) 77#define auto(var,expr) decltype(expr) var = (expr)
76 78
77// very ugly macro that basicaly declares and initialises a variable 79// very ugly macro that basically declares and initialises a variable
78// that is in scope for the next statement only 80// that is in scope for the next statement only
79// works only for stuff that can be assigned 0 and converts to false 81// works only for stuff that can be assigned 0 and converts to false
80// (note: works great for pointers) 82// (note: works great for pointers)
81// most ugly macro I ever wrote 83// most ugly macro I ever wrote
82#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 84#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
… …
96// as a is often a constant while b is the variable. it is still a bug, though. 98// as a is often a constant while b is the variable. it is still a bug, though.
97template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; } 99template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
98template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; } 100template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
99template<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; } 101template<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; }
100 102
101template<typename T> static inline void min_it (T &v, T m) { v = min (v, m); } 103template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); }
102template<typename T> static inline void max_it (T &v, T m) { v = max (v, m); } 104template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); }
103template<typename T> static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); } 105template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); }
104 106
105template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } 107template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
106 108
107template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); } 109template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
108template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); } 110template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
109 111
112// sign returns -1 or +1
113template<typename T>
114static inline T sign (T v) { return v < 0 ? -1 : +1; }
115// relies on 2c representation
116template<>
117inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
118
119// sign0 returns -1, 0 or +1
120template<typename T>
121static inline T sign0 (T v) { return v ? sign (v) : 0; }
122
123// div* only work correctly for div > 0
110// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 124// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
111template<typename T> static inline T div (T val, T div) { return (val + div / 2) / div; } 125template<typename T> static inline T div (T val, T div)
126{
127 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
128}
112// div, round-up 129// div, round-up
113template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 130template<typename T> static inline T div_ru (T val, T div)
131{
132 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
133}
114// div, round-down 134// div, round-down
115template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 135template<typename T> static inline T div_rd (T val, T div)
136{
137 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
138}
116 139
140// lerp* only work correctly for min_in < max_in
141// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
117template<typename T> 142template<typename T>
118static inline T 143static inline T
119lerp (T val, T min_in, T max_in, T min_out, T max_out) 144lerp (T val, T min_in, T max_in, T min_out, T max_out)
120{ 145{
121 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 146 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
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378// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 403// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
379// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 404// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
380// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps 405// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
381struct tausworthe_random_generator 406struct tausworthe_random_generator
382{ 407{
383 // generator
384 uint32_t state [4]; 408 uint32_t state [4];
385 409
386 void operator =(const tausworthe_random_generator &src) 410 void operator =(const tausworthe_random_generator &src)
387 { 411 {
388 state [0] = src.state [0]; 412 state [0] = src.state [0];
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391 state [3] = src.state [3]; 415 state [3] = src.state [3];
392 } 416 }
393 417
394 void seed (uint32_t seed); 418 void seed (uint32_t seed);
395 uint32_t next (); 419 uint32_t next ();
420};
396 421
422// Xorshift RNGs, George Marsaglia
423// http://www.jstatsoft.org/v08/i14/paper
424// this one is about 40% faster than the tausworthe one above (i.e. not much),
425// despite the inlining, and has the issue of only creating 2**32-1 numbers.
426// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
427struct xorshift_random_generator
428{
429 uint32_t x, y;
430
431 void operator =(const xorshift_random_generator &src)
432 {
433 x = src.x;
434 y = src.y;
435 }
436
437 void seed (uint32_t seed)
438 {
439 x = seed;
440 y = seed * 69069U;
441 }
442
443 uint32_t next ()
444 {
445 uint32_t t = x ^ (x << 10);
446 x = y;
447 y = y ^ (y >> 13) ^ t ^ (t >> 10);
448 return y;
449 }
450};
451
452template<class generator>
453struct random_number_generator : generator
454{
397 // uniform distribution, 0 .. max (0, num - 1) 455 // uniform distribution, 0 .. max (0, num - 1)
398 uint32_t operator ()(uint32_t num) 456 uint32_t operator ()(uint32_t num)
399 { 457 {
400 return is_constant (num) 458 return !is_constant (num) ? get_range (num) // non-constant
401 ? (next () * (uint64_t)num) >> 32U 459 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
402 : get_range (num); 460 : this->next () & (num - 1); // constant, power-of-two
403 } 461 }
404 462
405 // return a number within (min .. max) 463 // return a number within (min .. max)
406 int operator () (int r_min, int r_max) 464 int operator () (int r_min, int r_max)
407 { 465 {
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418protected: 476protected:
419 uint32_t get_range (uint32_t r_max); 477 uint32_t get_range (uint32_t r_max);
420 int get_range (int r_min, int r_max); 478 int get_range (int r_min, int r_max);
421}; 479};
422 480
423typedef tausworthe_random_generator rand_gen; 481typedef random_number_generator<tausworthe_random_generator> rand_gen;
424 482
425extern rand_gen rndm, rmg_rndm; 483extern rand_gen rndm, rmg_rndm;
426 484
427INTERFACE_CLASS (attachable) 485INTERFACE_CLASS (attachable)
428struct refcnt_base 486struct refcnt_base
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497 555
498struct str_hash 556struct str_hash
499{ 557{
500 std::size_t operator ()(const char *s) const 558 std::size_t operator ()(const char *s) const
501 { 559 {
502 unsigned long hash = 0; 560#if 0
561 uint32_t hash = 0;
503 562
504 /* use the one-at-a-time hash function, which supposedly is 563 /* use the one-at-a-time hash function, which supposedly is
505 * better than the djb2-like one used by perl5.005, but 564 * better than the djb2-like one used by perl5.005, but
506 * certainly is better then the bug used here before. 565 * certainly is better then the bug used here before.
507 * see http://burtleburtle.net/bob/hash/doobs.html 566 * see http://burtleburtle.net/bob/hash/doobs.html
… …
514 } 573 }
515 574
516 hash += hash << 3; 575 hash += hash << 3;
517 hash ^= hash >> 11; 576 hash ^= hash >> 11;
518 hash += hash << 15; 577 hash += hash << 15;
578#else
579 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
580 // it is about twice as fast as the one-at-a-time one,
581 // with good distribution.
582 // FNV-1a is faster on many cpus because the multiplication
583 // runs concurrent with the looping logic.
584 uint32_t hash = 2166136261;
585
586 while (*s)
587 hash = (hash ^ *s++) * 16777619;
588#endif
519 589
520 return hash; 590 return hash;
521 } 591 }
522}; 592};
523 593
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618 erase (&obj); 688 erase (&obj);
619 } 689 }
620}; 690};
621 691
622// basically does what strncpy should do, but appends "..." to strings exceeding length 692// basically does what strncpy should do, but appends "..." to strings exceeding length
693// returns the number of bytes actually used (including \0)
623void assign (char *dst, const char *src, int maxlen); 694int assign (char *dst, const char *src, int maxsize);
624 695
625// type-safe version of assign 696// type-safe version of assign
626template<int N> 697template<int N>
627inline void assign (char (&dst)[N], const char *src) 698inline int assign (char (&dst)[N], const char *src)
628{ 699{
629 assign ((char *)&dst, src, N); 700 return assign ((char *)&dst, src, N);
630} 701}
631 702
632typedef double tstamp; 703typedef double tstamp;
633 704
634// return current time as timestamp 705// return current time as timestamp
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636 707
637int similar_direction (int a, int b); 708int similar_direction (int a, int b);
638 709
639// like sprintf, but returns a "static" buffer 710// like sprintf, but returns a "static" buffer
640const char *format (const char *format, ...); 711const char *format (const char *format, ...);
712
713// safety-check player input which will become object->msg
714bool msg_is_safe (const char *msg);
641 715
642///////////////////////////////////////////////////////////////////////////// 716/////////////////////////////////////////////////////////////////////////////
643// threads, very very thin wrappers around pthreads 717// threads, very very thin wrappers around pthreads
644 718
645struct thread 719struct thread

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