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Revision 1.86 by root, Sat Jan 3 01:04:19 2009 UTC vs.
Revision 1.129 by root, Sat Dec 1 20:22:13 2018 UTC

1/* 1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG. 2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 * 3 *
4 * Copyright (©) 2017,2018 Marc Alexander Lehmann / the Deliantra team
4 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team 5 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 * 6 *
6 * Deliantra is free software: you can redistribute it and/or modify 7 * Deliantra is free software: you can redistribute it and/or modify it under
7 * it under the terms of the GNU General Public License as published by 8 * the terms of the Affero GNU General Public License as published by the
8 * the Free Software Foundation, either version 3 of the License, or 9 * Free Software Foundation, either version 3 of the License, or (at your
9 * (at your option) any later version. 10 * option) any later version.
10 * 11 *
11 * This program is distributed in the hope that it will be useful, 12 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details. 15 * GNU General Public License for more details.
15 * 16 *
16 * You should have received a copy of the GNU General Public License 17 * You should have received a copy of the Affero GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 * and the GNU General Public License along with this program. If not, see
19 * <http://www.gnu.org/licenses/>.
18 * 20 *
19 * The authors can be reached via e-mail to <support@deliantra.net> 21 * The authors can be reached via e-mail to <support@deliantra.net>
20 */ 22 */
21 23
22#ifndef UTIL_H__ 24#ifndef UTIL_H__
23#define UTIL_H__ 25#define UTIL_H__
26
27#include <compiler.h>
24 28
25#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0 29#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs 30#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27#define PREFER_MALLOC 0 // use malloc and not the slice allocator 31#define PREFER_MALLOC 0 // use malloc and not the slice allocator
28
29#if __GNUC__ >= 3
30# define is_constant(c) __builtin_constant_p (c)
31# define expect(expr,value) __builtin_expect ((expr),(value))
32# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
33# define noinline __attribute__((__noinline__))
34#else
35# define is_constant(c) 0
36# define expect(expr,value) (expr)
37# define prefetch(addr,rw,locality)
38# define noinline
39#endif
40
41#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
42# define decltype(x) typeof(x)
43#endif
44
45// put into ifs if you are very sure that the expression
46// is mostly true or mosty false. note that these return
47// booleans, not the expression.
48#define expect_false(expr) expect ((expr) ? 1 : 0, 0)
49#define expect_true(expr) expect ((expr) ? 1 : 0, 1)
50 32
51#include <pthread.h> 33#include <pthread.h>
52 34
53#include <cstddef> 35#include <cstddef>
54#include <cmath> 36#include <cmath>
55#include <new> 37#include <new>
56#include <vector> 38#include <vector>
57 39
58#include <glib.h> 40#include <glib.h>
41
42#include <flat_hash_map.hpp>
59 43
60#include <shstr.h> 44#include <shstr.h>
61#include <traits.h> 45#include <traits.h>
62 46
63#if DEBUG_SALLOC 47#if DEBUG_SALLOC
71# define g_slice_alloc0(s) calloc (1, (s)) 55# define g_slice_alloc0(s) calloc (1, (s))
72# define g_slice_alloc(s) malloc ((s)) 56# define g_slice_alloc(s) malloc ((s))
73# define g_slice_free1(s,p) free ((p)) 57# define g_slice_free1(s,p) free ((p))
74#endif 58#endif
75 59
76// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
77#define auto(var,expr) decltype(expr) var = (expr)
78
79// very ugly macro that basically declares and initialises a variable 60// very ugly macro that basically declares and initialises a variable
80// that is in scope for the next statement only 61// that is in scope for the next statement only
81// works only for stuff that can be assigned 0 and converts to false 62// works only for stuff that can be assigned 0 and converts to false
82// (note: works great for pointers) 63// (note: works great for pointers)
83// most ugly macro I ever wrote 64// most ugly macro I ever wrote
89 70
90// in range excluding end 71// in range excluding end
91#define IN_RANGE_EXC(val,beg,end) \ 72#define IN_RANGE_EXC(val,beg,end) \
92 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg)) 73 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
93 74
94void cleanup (const char *cause, bool make_core = false); 75ecb_cold void cleanup (const char *cause, bool make_core = false);
95void fork_abort (const char *msg); 76ecb_cold void fork_abort (const char *msg);
96 77
97// rationale for using (U) not (T) is to reduce signed/unsigned issues, 78// rationale for using (U) not (T) is to reduce signed/unsigned issues,
98// as a is often a constant while b is the variable. it is still a bug, though. 79// as a is often a constant while b is the variable. it is still a bug, though.
99template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; } 80template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
100template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; } 81template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
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; } 82template<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; }
102 83
103template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); } 84template<typename T, typename U> static inline void min_it (T &v, U m) { v = min (v, (T)m); }
104template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); } 85template<typename T, typename U> static inline void max_it (T &v, U m) { v = max (v, (T)m); }
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); } 86template<typename T, typename U, typename V> static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); }
112// sign returns -1 or +1 93// sign returns -1 or +1
113template<typename T> 94template<typename T>
114static inline T sign (T v) { return v < 0 ? -1 : +1; } 95static inline T sign (T v) { return v < 0 ? -1 : +1; }
115// relies on 2c representation 96// relies on 2c representation
116template<> 97template<>
117inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } 98inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
99template<>
100inline sint16 sign (sint16 v) { return 1 - (sint16 (uint16 (v) >> 15) * 2); }
101template<>
102inline sint32 sign (sint32 v) { return 1 - (sint32 (uint32 (v) >> 31) * 2); }
118 103
119// sign0 returns -1, 0 or +1 104// sign0 returns -1, 0 or +1
120template<typename T> 105template<typename T>
121static inline T sign0 (T v) { return v ? sign (v) : 0; } 106static inline T sign0 (T v) { return v ? sign (v) : 0; }
122 107
108//clashes with C++0x
109template<typename T, typename U>
110static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
111
112// div* only work correctly for div > 0
123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 113// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
124template<typename T> static inline T div (T val, T div) { return (val + div / 2) / div; } 114template<typename T> static inline T div (T val, T div)
115{
116 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
117}
118
119template<> inline float div (float val, float div) { return val / div; }
120template<> inline double div (double val, double div) { return val / div; }
121
125// div, round-up 122// div, round-up
126template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; } 123template<typename T> static inline T div_ru (T val, T div)
124{
125 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
126}
127// div, round-down 127// div, round-down
128template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; } 128template<typename T> static inline T div_rd (T val, T div)
129{
130 return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
131}
129 132
133// lerp* only work correctly for min_in < max_in
134// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
130template<typename T> 135template<typename T>
131static inline T 136static inline T
132lerp (T val, T min_in, T max_in, T min_out, T max_out) 137lerp (T val, T min_in, T max_in, T min_out, T max_out)
133{ 138{
134 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in); 139 return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
193 int32_t d = b - a; 198 int32_t d = b - a;
194 d &= d >> 31; 199 d &= d >> 31;
195 return b - d; 200 return b - d;
196} 201}
197 202
198// this is much faster than crossfires original algorithm 203// this is much faster than crossfire's original algorithm
199// on modern cpus 204// on modern cpus
200inline int 205inline int
201isqrt (int n) 206isqrt (int n)
202{ 207{
203 return (int)sqrtf ((float)n); 208 return (int)sqrtf ((float)n);
209}
210
211// this is kind of like the ^^ operator, if it would exist, without sequence point.
212// more handy than it looks like, due to the implicit !! done on its arguments
213inline bool
214logical_xor (bool a, bool b)
215{
216 return a != b;
217}
218
219inline bool
220logical_implies (bool a, bool b)
221{
222 return a <= b;
204} 223}
205 224
206// this is only twice as fast as naive sqrtf (dx*dy+dy*dy) 225// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
207#if 0 226#if 0
208// and has a max. error of 6 in the range -100..+100. 227// and has a max. error of 6 in the range -100..+100.
209#else 228#else
210// and has a max. error of 9 in the range -100..+100. 229// and has a max. error of 9 in the range -100..+100.
211#endif 230#endif
212inline int 231inline int
213idistance (int dx, int dy) 232idistance (int dx, int dy)
214{ 233{
215 unsigned int dx_ = abs (dx); 234 unsigned int dx_ = abs (dx);
216 unsigned int dy_ = abs (dy); 235 unsigned int dy_ = abs (dy);
217 236
218#if 0 237#if 0
219 return dx_ > dy_ 238 return dx_ > dy_
222#else 241#else
223 return dx_ + dy_ - min (dx_, dy_) * 5 / 8; 242 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
224#endif 243#endif
225} 244}
226 245
246// can be substantially faster than floor, if your value range allows for it
247template<typename T>
248inline T
249fastfloor (T x)
250{
251 return std::floor (x);
252}
253
254inline float
255fastfloor (float x)
256{
257 return sint32(x) - (x < 0);
258}
259
260inline double
261fastfloor (double x)
262{
263 return sint64(x) - (x < 0);
264}
265
227/* 266/*
228 * absdir(int): Returns a number between 1 and 8, which represent 267 * absdir(int): Returns a number between 1 and 8, which represent
229 * the "absolute" direction of a number (it actually takes care of 268 * the "absolute" direction of a number (it actually takes care of
230 * "overflow" in previous calculations of a direction). 269 * "overflow" in previous calculations of a direction).
231 */ 270 */
233absdir (int d) 272absdir (int d)
234{ 273{
235 return ((d - 1) & 7) + 1; 274 return ((d - 1) & 7) + 1;
236} 275}
237 276
277#define for_all_bits_sparse_32(mask, idxvar) \
278 for (uint32_t idxvar, mask_ = mask; \
279 mask_ && ((idxvar = ecb_ctz32 (mask_)), mask_ &= ~(1 << idxvar), 1);)
280
238extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
239 282
240void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n);
241void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src);
242 285
243// strictly the same as g_slice_alloc, but never returns 0 286// strictly the same as g_slice_alloc, but never returns 0
244template<typename T> 287template<typename T>
245inline T *salloc (int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T)); } 288inline T *salloc (int n = 1) { return (T *)salloc_ (n * sizeof (T)); }
246 289
247// also copies src into the new area, like "memdup" 290// also copies src into the new area, like "memdup"
248// if src is 0, clears the memory 291// if src is 0, clears the memory
249template<typename T> 292template<typename T>
250inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); } 293inline T *salloc (int n, T *src) { return (T *)salloc_ (n * sizeof (T), (void *)src); }
251 294
252// clears the memory 295// clears the memory
253template<typename T> 296template<typename T>
254inline T *salloc0(int n = 1) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0); } 297inline T *salloc0(int n = 1) { return (T *)salloc_ (n * sizeof (T), 0); }
255 298
256// for symmetry 299// for symmetry
257template<typename T> 300template<typename T>
258inline void sfree (T *ptr, int n = 1) throw () 301inline void sfree (T *ptr, int n = 1) noexcept
259{ 302{
260 if (expect_true (ptr)) 303 if (expect_true (ptr))
261 { 304 {
262 slice_alloc -= n * sizeof (T); 305 slice_alloc -= n * sizeof (T);
263 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T)); 306 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
264 g_slice_free1 (n * sizeof (T), (void *)ptr); 307 g_slice_free1 (n * sizeof (T), (void *)ptr);
265 assert (slice_alloc >= 0);//D
266 } 308 }
267} 309}
268 310
269// nulls the pointer 311// nulls the pointer
270template<typename T> 312template<typename T>
271inline void sfree0 (T *&ptr, int n = 1) throw () 313inline void sfree0 (T *&ptr, int n = 1) noexcept
272{ 314{
273 sfree<T> (ptr, n); 315 sfree<T> (ptr, n);
274 ptr = 0; 316 ptr = 0;
275} 317}
276 318
344 typedef const Tp *const_pointer; 386 typedef const Tp *const_pointer;
345 typedef Tp &reference; 387 typedef Tp &reference;
346 typedef const Tp &const_reference; 388 typedef const Tp &const_reference;
347 typedef Tp value_type; 389 typedef Tp value_type;
348 390
349 template <class U> 391 template <class U>
350 struct rebind 392 struct rebind
351 { 393 {
352 typedef slice_allocator<U> other; 394 typedef slice_allocator<U> other;
353 }; 395 };
354 396
355 slice_allocator () throw () { } 397 slice_allocator () noexcept { }
356 slice_allocator (const slice_allocator &) throw () { } 398 slice_allocator (const slice_allocator &) noexcept { }
357 template<typename Tp2> 399 template<typename Tp2>
358 slice_allocator (const slice_allocator<Tp2> &) throw () { } 400 slice_allocator (const slice_allocator<Tp2> &) noexcept { }
359 401
360 ~slice_allocator () { } 402 ~slice_allocator () { }
361 403
362 pointer address (reference x) const { return &x; } 404 pointer address (reference x) const { return &x; }
363 const_pointer address (const_reference x) const { return &x; } 405 const_pointer address (const_reference x) const { return &x; }
370 void deallocate (pointer p, size_type n) 412 void deallocate (pointer p, size_type n)
371 { 413 {
372 sfree<Tp> (p, n); 414 sfree<Tp> (p, n);
373 } 415 }
374 416
375 size_type max_size () const throw () 417 size_type max_size () const noexcept
376 { 418 {
377 return size_t (-1) / sizeof (Tp); 419 return size_t (-1) / sizeof (Tp);
378 } 420 }
379 421
380 void construct (pointer p, const Tp &val) 422 void construct (pointer p, const Tp &val)
386 { 428 {
387 p->~Tp (); 429 p->~Tp ();
388 } 430 }
389}; 431};
390 432
391// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. 433// basically a memory area, but refcounted
392// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps 434struct refcnt_buf
393// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
394struct tausworthe_random_generator
395{ 435{
396 uint32_t state [4]; 436 char *data;
397 437
398 void operator =(const tausworthe_random_generator &src) 438 refcnt_buf (size_t size = 0);
399 { 439 refcnt_buf (void *data, size_t size);
400 state [0] = src.state [0];
401 state [1] = src.state [1];
402 state [2] = src.state [2];
403 state [3] = src.state [3];
404 }
405 440
406 void seed (uint32_t seed); 441 refcnt_buf (const refcnt_buf &src)
407 uint32_t next ();
408};
409
410// Xorshift RNGs, George Marsaglia
411// http://www.jstatsoft.org/v08/i14/paper
412// this one is about 40% faster than the tausworthe one above (i.e. not much),
413// despite the inlining, and has the issue of only creating 2**32-1 numbers.
414// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
415struct xorshift_random_generator
416{
417 uint32_t x, y;
418
419 void operator =(const xorshift_random_generator &src)
420 { 442 {
421 x = src.x; 443 data = src.data;
422 y = src.y; 444 inc ();
423 } 445 }
424 446
425 void seed (uint32_t seed) 447 ~refcnt_buf ();
426 {
427 x = seed;
428 y = seed * 69069U;
429 }
430 448
431 uint32_t next () 449 refcnt_buf &operator =(const refcnt_buf &src);
450
451 operator char *()
432 { 452 {
433 uint32_t t = x ^ (x << 10);
434 x = y;
435 y = y ^ (y >> 13) ^ t ^ (t >> 10);
436 return y; 453 return data;
437 } 454 }
438};
439 455
440template<class generator> 456 size_t size () const
441struct random_number_generator : generator
442{
443 // uniform distribution, 0 .. max (0, num - 1)
444 uint32_t operator ()(uint32_t num)
445 { 457 {
446 return !is_constant (num) ? get_range (num) // non-constant 458 return _size ();
447 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
448 : this->next () & (num - 1); // constant, power-of-two
449 }
450
451 // return a number within (min .. max)
452 int operator () (int r_min, int r_max)
453 {
454 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
455 ? r_min + operator ()(r_max - r_min + 1)
456 : get_range (r_min, r_max);
457 }
458
459 double operator ()()
460 {
461 return this->next () / (double)0xFFFFFFFFU;
462 } 459 }
463 460
464protected: 461protected:
465 uint32_t get_range (uint32_t r_max); 462 enum {
466 int get_range (int r_min, int r_max); 463 overhead = sizeof (uint32_t) * 2
467}; 464 };
468 465
469typedef random_number_generator<tausworthe_random_generator> rand_gen; 466 uint32_t &_size () const
467 {
468 return ((unsigned int *)data)[-2];
469 }
470 470
471extern rand_gen rndm, rmg_rndm; 471 uint32_t &_refcnt () const
472 {
473 return ((unsigned int *)data)[-1];
474 }
475
476 void _alloc (uint32_t size)
477 {
478 data = ((char *)salloc<char> (size + overhead)) + overhead;
479 _size () = size;
480 _refcnt () = 1;
481 }
482
483 void _dealloc ();
484
485 void inc ()
486 {
487 ++_refcnt ();
488 }
489
490 void dec ()
491 {
492 if (!--_refcnt ())
493 _dealloc ();
494 }
495};
472 496
473INTERFACE_CLASS (attachable) 497INTERFACE_CLASS (attachable)
474struct refcnt_base 498struct refcnt_base
475{ 499{
476 typedef int refcnt_t; 500 typedef int refcnt_t;
491 // p if not null 515 // p if not null
492 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; } 516 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
493 517
494 void refcnt_dec () 518 void refcnt_dec ()
495 { 519 {
496 if (!is_constant (p)) 520 if (!ecb_is_constant (p))
497 --*refcnt_ref (); 521 --*refcnt_ref ();
498 else if (p) 522 else if (p)
499 --p->refcnt; 523 --p->refcnt;
500 } 524 }
501 525
502 void refcnt_inc () 526 void refcnt_inc ()
503 { 527 {
504 if (!is_constant (p)) 528 if (!ecb_is_constant (p))
505 ++*refcnt_ref (); 529 ++*refcnt_ref ();
506 else if (p) 530 else if (p)
507 ++p->refcnt; 531 ++p->refcnt;
508 } 532 }
509 533
538typedef refptr<maptile> maptile_ptr; 562typedef refptr<maptile> maptile_ptr;
539typedef refptr<object> object_ptr; 563typedef refptr<object> object_ptr;
540typedef refptr<archetype> arch_ptr; 564typedef refptr<archetype> arch_ptr;
541typedef refptr<client> client_ptr; 565typedef refptr<client> client_ptr;
542typedef refptr<player> player_ptr; 566typedef refptr<player> player_ptr;
567typedef refptr<region> region_ptr;
568
569#define STRHSH_NULL 2166136261
570
571static inline uint32_t
572strhsh (const char *s)
573{
574 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
575 // it is about twice as fast as the one-at-a-time one,
576 // with good distribution.
577 // FNV-1a is faster on many cpus because the multiplication
578 // runs concurrently with the looping logic.
579 // we modify the hash a bit to improve its distribution
580 uint32_t hash = STRHSH_NULL;
581
582 while (*s)
583 hash = (hash ^ *s++) * 16777619U;
584
585 return hash ^ (hash >> 16);
586}
587
588static inline uint32_t
589memhsh (const char *s, size_t len)
590{
591 uint32_t hash = STRHSH_NULL;
592
593 while (len--)
594 hash = (hash ^ *s++) * 16777619U;
595
596 return hash;
597}
543 598
544struct str_hash 599struct str_hash
545{ 600{
546 std::size_t operator ()(const char *s) const 601 std::size_t operator ()(const char *s) const
547 { 602 {
548#if 0
549 uint32_t hash = 0;
550
551 /* use the one-at-a-time hash function, which supposedly is
552 * better than the djb2-like one used by perl5.005, but
553 * certainly is better then the bug used here before.
554 * see http://burtleburtle.net/bob/hash/doobs.html
555 */
556 while (*s)
557 {
558 hash += *s++;
559 hash += hash << 10;
560 hash ^= hash >> 6;
561 }
562
563 hash += hash << 3;
564 hash ^= hash >> 11;
565 hash += hash << 15;
566#else
567 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
568 // it is about twice as fast as the one-at-a-time one,
569 // with good distribution.
570 // FNV-1a is faster on many cpus because the multiplication
571 // runs concurrent with the looping logic.
572 uint32_t hash = 2166136261;
573
574 while (*s)
575 hash = (hash ^ *s++) * 16777619;
576#endif
577
578 return hash; 603 return strhsh (s);
579 } 604 }
605
606 std::size_t operator ()(const shstr &s) const
607 {
608 return strhsh (s);
609 }
610
611 typedef ska::power_of_two_hash_policy hash_policy;
580}; 612};
581 613
582struct str_equal 614struct str_equal
583{ 615{
584 bool operator ()(const char *a, const char *b) const 616 bool operator ()(const char *a, const char *b) const
610 } 642 }
611}; 643};
612 644
613// This container blends advantages of linked lists 645// This container blends advantages of linked lists
614// (efficiency) with vectors (random access) by 646// (efficiency) with vectors (random access) by
615// by using an unordered vector and storing the vector 647// using an unordered vector and storing the vector
616// index inside the object. 648// index inside the object.
617// 649//
618// + memory-efficient on most 64 bit archs 650// + memory-efficient on most 64 bit archs
619// + O(1) insert/remove 651// + O(1) insert/remove
620// + free unique (but varying) id for inserted objects 652// + free unique (but varying) id for inserted objects
657 insert (&obj); 689 insert (&obj);
658 } 690 }
659 691
660 void erase (T *obj) 692 void erase (T *obj)
661 { 693 {
662 unsigned int pos = obj->*indexmember; 694 object_vector_index pos = obj->*indexmember;
663 obj->*indexmember = 0; 695 obj->*indexmember = 0;
664 696
665 if (pos < this->size ()) 697 if (pos < this->size ())
666 { 698 {
667 (*this)[pos - 1] = (*this)[this->size () - 1]; 699 (*this)[pos - 1] = (*this)[this->size () - 1];
675 { 707 {
676 erase (&obj); 708 erase (&obj);
677 } 709 }
678}; 710};
679 711
712/////////////////////////////////////////////////////////////////////////////
713
714// something like a vector or stack, but without
715// out of bounds checking
716template<typename T>
717struct fixed_stack
718{
719 T *data;
720 int size;
721 int max;
722
723 fixed_stack ()
724 : size (0), data (0)
725 {
726 }
727
728 fixed_stack (int max)
729 : size (0), max (max)
730 {
731 data = salloc<T> (max);
732 }
733
734 void reset (int new_max)
735 {
736 sfree (data, max);
737 size = 0;
738 max = new_max;
739 data = salloc<T> (max);
740 }
741
742 void free ()
743 {
744 sfree (data, max);
745 data = 0;
746 }
747
748 ~fixed_stack ()
749 {
750 sfree (data, max);
751 }
752
753 T &operator[](int idx)
754 {
755 return data [idx];
756 }
757
758 void push (T v)
759 {
760 data [size++] = v;
761 }
762
763 T &pop ()
764 {
765 return data [--size];
766 }
767
768 T remove (int idx)
769 {
770 T v = data [idx];
771
772 data [idx] = data [--size];
773
774 return v;
775 }
776};
777
778/////////////////////////////////////////////////////////////////////////////
779
680// basically does what strncpy should do, but appends "..." to strings exceeding length 780// basically does what strncpy should do, but appends "..." to strings exceeding length
781// returns the number of bytes actually used (including \0)
681void assign (char *dst, const char *src, int maxlen); 782int assign (char *dst, const char *src, int maxsize);
682 783
683// type-safe version of assign 784// type-safe version of assign
684template<int N> 785template<int N>
685inline void assign (char (&dst)[N], const char *src) 786inline int assign (char (&dst)[N], const char *src)
686{ 787{
687 assign ((char *)&dst, src, N); 788 return assign ((char *)&dst, src, N);
688} 789}
689 790
690typedef double tstamp; 791typedef double tstamp;
691 792
692// return current time as timestamp 793// return current time as timestamp
693tstamp now (); 794tstamp now ();
694 795
695int similar_direction (int a, int b); 796int similar_direction (int a, int b);
696 797
697// like sprintf, but returns a "static" buffer 798// like v?sprintf, but returns a "static" buffer
698const char *format (const char *format, ...); 799char *vformat (const char *format, va_list ap);
800char *format (const char *format, ...) ecb_attribute ((format (printf, 1, 2)));
801
802// safety-check player input which will become object->msg
803bool msg_is_safe (const char *msg);
699 804
700///////////////////////////////////////////////////////////////////////////// 805/////////////////////////////////////////////////////////////////////////////
701// threads, very very thin wrappers around pthreads 806// threads, very very thin wrappers around pthreads
702 807
703struct thread 808struct thread

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