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Revision 1.83 by root, Tue Dec 30 07:24:16 2008 UTC vs.
Revision 1.132 by root, Thu Dec 20 04:40:15 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__
24 26
25#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0 27#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs 28#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27#define PREFER_MALLOC 0 // use malloc and not the slice allocator 29#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#else
34# define is_constant(c) 0
35# define expect(expr,value) (expr)
36# define prefetch(addr,rw,locality)
37#endif
38
39#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
40# define decltype(x) typeof(x)
41#endif
42
43// put into ifs if you are very sure that the expression
44// is mostly true or mosty false. note that these return
45// booleans, not the expression.
46#define expect_false(expr) expect ((expr) != 0, 0)
47#define expect_true(expr) expect ((expr) != 0, 1)
48 30
49#include <pthread.h> 31#include <pthread.h>
50 32
51#include <cstddef> 33#include <cstddef>
52#include <cmath> 34#include <cmath>
53#include <new> 35#include <new>
54#include <vector> 36#include <vector>
55 37
56#include <glib.h> 38#include <glib.h>
57 39
40#include <flat_hash_map.hpp>
41
58#include <shstr.h> 42#include <shstr.h>
59#include <traits.h> 43#include <traits.h>
44
45#include "ecb.h"
60 46
61#if DEBUG_SALLOC 47#if DEBUG_SALLOC
62# define g_slice_alloc0(s) debug_slice_alloc0(s) 48# define g_slice_alloc0(s) debug_slice_alloc0(s)
63# define g_slice_alloc(s) debug_slice_alloc(s) 49# define g_slice_alloc(s) debug_slice_alloc(s)
64# define g_slice_free1(s,p) debug_slice_free1(s,p) 50# define g_slice_free1(s,p) debug_slice_free1(s,p)
… …
69# define g_slice_alloc0(s) calloc (1, (s)) 55# define g_slice_alloc0(s) calloc (1, (s))
70# define g_slice_alloc(s) malloc ((s)) 56# define g_slice_alloc(s) malloc ((s))
71# define g_slice_free1(s,p) free ((p)) 57# define g_slice_free1(s,p) free ((p))
72#endif 58#endif
73 59
74// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75#define auto(var,expr) decltype(expr) var = (expr)
76
77// very ugly macro that basically declares and initialises a variable 60// very ugly macro that basically declares and initialises a variable
78// that is in scope for the next statement only 61// that is in scope for the next statement only
79// 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
80// (note: works great for pointers) 63// (note: works great for pointers)
81// most ugly macro I ever wrote 64// most ugly macro I ever wrote
… …
87 70
88// in range excluding end 71// in range excluding end
89#define IN_RANGE_EXC(val,beg,end) \ 72#define IN_RANGE_EXC(val,beg,end) \
90 ((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))
91 74
92void cleanup (const char *cause, bool make_core = false); 75ecb_cold void cleanup (const char *cause, bool make_core = false);
93void fork_abort (const char *msg); 76ecb_cold void fork_abort (const char *msg);
94 77
95// 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,
96// 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.
97template<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; }
98template<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; }
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; } 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; }
100 83
101template<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); }
102template<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); }
103template<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); }
… …
110// sign returns -1 or +1 93// sign returns -1 or +1
111template<typename T> 94template<typename T>
112static inline T sign (T v) { return v < 0 ? -1 : +1; } 95static inline T sign (T v) { return v < 0 ? -1 : +1; }
113// relies on 2c representation 96// relies on 2c representation
114template<> 97template<>
115inline 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); }
116 103
117// sign0 returns -1, 0 or +1 104// sign0 returns -1, 0 or +1
118template<typename T> 105template<typename T>
119static inline T sign0 (T v) { return v ? sign (v) : 0; } 106static inline T sign0 (T v) { return v ? sign (v) : 0; }
120 107
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
121// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 113// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
122template<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 ecb_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
123// div, round-up 122// div, round-up
124template<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 ecb_expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
126}
125// div, round-down 127// div, round-down
126template<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 ecb_expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div;
131}
127 132
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
128template<typename T> 135template<typename T>
129static inline T 136static inline T
130lerp (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)
131{ 138{
132 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);
… …
191 int32_t d = b - a; 198 int32_t d = b - a;
192 d &= d >> 31; 199 d &= d >> 31;
193 return b - d; 200 return b - d;
194} 201}
195 202
196// this is much faster than crossfires original algorithm 203// this is much faster than crossfire's original algorithm
197// on modern cpus 204// on modern cpus
198inline int 205inline int
199isqrt (int n) 206isqrt (int n)
200{ 207{
201 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;
202} 223}
203 224
204// 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)
205#if 0 226#if 0
206// 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.
207#else 228#else
208// 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.
209#endif 230#endif
210inline int 231inline int
211idistance (int dx, int dy) 232idistance (int dx, int dy)
212{ 233{
213 unsigned int dx_ = abs (dx); 234 unsigned int dx_ = abs (dx);
214 unsigned int dy_ = abs (dy); 235 unsigned int dy_ = abs (dy);
215 236
216#if 0 237#if 0
217 return dx_ > dy_ 238 return dx_ > dy_
… …
220#else 241#else
221 return dx_ + dy_ - min (dx_, dy_) * 5 / 8; 242 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
222#endif 243#endif
223} 244}
224 245
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
225/* 266/*
226 * absdir(int): Returns a number between 1 and 8, which represent 267 * absdir(int): Returns a number between 1 and 8, which represent
227 * the "absolute" direction of a number (it actually takes care of 268 * the "absolute" direction of a number (it actually takes care of
228 * "overflow" in previous calculations of a direction). 269 * "overflow" in previous calculations of a direction).
229 */ 270 */
… …
231absdir (int d) 272absdir (int d)
232{ 273{
233 return ((d - 1) & 7) + 1; 274 return ((d - 1) & 7) + 1;
234} 275}
235 276
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
236extern ssize_t slice_alloc; // statistics 281extern ssize_t slice_alloc; // statistics
237 282
238void *salloc_ (int n) throw (std::bad_alloc); 283void *salloc_ (int n);
239void *salloc_ (int n, void *src) throw (std::bad_alloc); 284void *salloc_ (int n, void *src);
240 285
241// strictly the same as g_slice_alloc, but never returns 0 286// strictly the same as g_slice_alloc, but never returns 0
242template<typename T> 287template<typename T>
243inline 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)); }
244 289
245// also copies src into the new area, like "memdup" 290// also copies src into the new area, like "memdup"
246// if src is 0, clears the memory 291// if src is 0, clears the memory
247template<typename T> 292template<typename T>
248inline 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); }
249 294
250// clears the memory 295// clears the memory
251template<typename T> 296template<typename T>
252inline 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); }
253 298
254// for symmetry 299// for symmetry
255template<typename T> 300template<typename T>
256inline void sfree (T *ptr, int n = 1) throw () 301inline void sfree (T *ptr, int n = 1) noexcept
257{ 302{
258 if (expect_true (ptr)) 303 if (ecb_expect_true (ptr))
259 { 304 {
260 slice_alloc -= n * sizeof (T); 305 slice_alloc -= n * sizeof (T);
261 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T)); 306 if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
262 g_slice_free1 (n * sizeof (T), (void *)ptr); 307 g_slice_free1 (n * sizeof (T), (void *)ptr);
263 assert (slice_alloc >= 0);//D
264 } 308 }
265} 309}
266 310
267// nulls the pointer 311// nulls the pointer
268template<typename T> 312template<typename T>
269inline void sfree0 (T *&ptr, int n = 1) throw () 313inline void sfree0 (T *&ptr, int n = 1) noexcept
270{ 314{
271 sfree<T> (ptr, n); 315 sfree<T> (ptr, n);
272 ptr = 0; 316 ptr = 0;
273} 317}
274 318
… …
330 sfree ((char *)p, s); 374 sfree ((char *)p, s);
331 } 375 }
332}; 376};
333 377
334// a STL-compatible allocator that uses g_slice 378// a STL-compatible allocator that uses g_slice
335// boy, this is verbose 379// boy, this is much less verbose in newer C++ versions
336template<typename Tp> 380template<typename Tp>
337struct slice_allocator 381struct slice_allocator
338{ 382{
339 typedef size_t size_type; 383 using value_type = Tp;
340 typedef ptrdiff_t difference_type;
341 typedef Tp *pointer;
342 typedef const Tp *const_pointer;
343 typedef Tp &reference;
344 typedef const Tp &const_reference;
345 typedef Tp value_type;
346 384
347 template <class U> 385 slice_allocator () noexcept { }
348 struct rebind 386 template<class U> slice_allocator (const slice_allocator<U> &) noexcept {}
387
388 value_type *allocate (std::size_t n)
349 { 389 {
350 typedef slice_allocator<U> other; 390 return salloc<Tp> (n);
391 }
392
393 void deallocate (value_type *p, std::size_t n)
394 {
395 sfree<Tp> (p, n);
396 }
397};
398
399template<class T, class U>
400bool operator == (const slice_allocator<T> &, const slice_allocator<U> &) noexcept
401{
402 return true;
403}
404
405template<class T, class U>
406bool operator != (const slice_allocator<T> &x, const slice_allocator<U> &y) noexcept
407{
408 return !(x == y);
409}
410
411// basically a memory area, but refcounted
412struct refcnt_buf
413{
414 char *data;
415
416 refcnt_buf (size_t size = 0);
417 refcnt_buf (void *data, size_t size);
418
419 refcnt_buf (const refcnt_buf &src)
420 {
421 data = src.data;
422 inc ();
423 }
424
425 ~refcnt_buf ();
426
427 refcnt_buf &operator =(const refcnt_buf &src);
428
429 operator char *()
430 {
431 return data;
432 }
433
434 size_t size () const
435 {
436 return _size ();
437 }
438
439protected:
440 enum {
441 overhead = sizeof (uint32_t) * 2
351 }; 442 };
352 443
353 slice_allocator () throw () { } 444 uint32_t &_size () const
354 slice_allocator (const slice_allocator &) throw () { }
355 template<typename Tp2>
356 slice_allocator (const slice_allocator<Tp2> &) throw () { }
357
358 ~slice_allocator () { }
359
360 pointer address (reference x) const { return &x; }
361 const_pointer address (const_reference x) const { return &x; }
362
363 pointer allocate (size_type n, const_pointer = 0)
364 { 445 {
365 return salloc<Tp> (n); 446 return ((unsigned int *)data)[-2];
366 } 447 }
367 448
368 void deallocate (pointer p, size_type n) 449 uint32_t &_refcnt () const
369 { 450 {
370 sfree<Tp> (p, n); 451 return ((unsigned int *)data)[-1];
371 } 452 }
372 453
373 size_type max_size () const throw ()
374 {
375 return size_t (-1) / sizeof (Tp);
376 }
377
378 void construct (pointer p, const Tp &val)
379 {
380 ::new (p) Tp (val);
381 }
382
383 void destroy (pointer p)
384 {
385 p->~Tp ();
386 }
387};
388
389// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
390// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
391// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
392struct tausworthe_random_generator
393{
394 uint32_t state [4];
395
396 void operator =(const tausworthe_random_generator &src)
397 {
398 state [0] = src.state [0];
399 state [1] = src.state [1];
400 state [2] = src.state [2];
401 state [3] = src.state [3];
402 }
403
404 void seed (uint32_t seed);
405 uint32_t next ();
406};
407
408// Xorshift RNGs, George Marsaglia
409// http://www.jstatsoft.org/v08/i14/paper
410// this one is about 40% faster than the tausworthe one above (i.e. not much),
411// despite the inlining, and has the issue of only creating 2**32-1 numbers.
412struct xorshift_random_generator
413{
414 uint32_t x, y;
415
416 void operator =(const xorshift_random_generator &src)
417 {
418 x = src.x;
419 y = src.y;
420 }
421
422 void seed (uint32_t seed) 454 void _alloc (uint32_t size)
423 { 455 {
424 x = seed; 456 data = ((char *)salloc<char> (size + overhead)) + overhead;
425 y = seed * 69069U; 457 _size () = size;
458 _refcnt () = 1;
426 } 459 }
427 460
428 uint32_t next () 461 void _dealloc ();
429 {
430 uint32_t t = x ^ (x << 10);
431 x = y;
432 y = y ^ (y >> 13) ^ t ^ (t >> 10);
433 return y;
434 }
435};
436 462
437template<class generator> 463 void inc ()
438struct random_number_generator : generator
439{
440 // uniform distribution, 0 .. max (0, num - 1)
441 uint32_t operator ()(uint32_t num)
442 { 464 {
443 return !is_constant (num) ? get_range (num) // non-constant 465 ++_refcnt ();
444 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
445 : this->next () & (num - 1); // constant, power-of-two
446 } 466 }
447 467
448 // return a number within (min .. max) 468 void dec ()
449 int operator () (int r_min, int r_max)
450 { 469 {
451 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 470 if (!--_refcnt ())
452 ? r_min + operator ()(r_max - r_min + 1) 471 _dealloc ();
453 : get_range (r_min, r_max);
454 } 472 }
455
456 double operator ()()
457 {
458 return this->next () / (double)0xFFFFFFFFU;
459 }
460
461protected:
462 uint32_t get_range (uint32_t r_max);
463 int get_range (int r_min, int r_max);
464}; 473};
465
466typedef random_number_generator<tausworthe_random_generator> rand_gen;
467
468extern rand_gen rndm, rmg_rndm;
469 474
470INTERFACE_CLASS (attachable) 475INTERFACE_CLASS (attachable)
471struct refcnt_base 476struct refcnt_base
472{ 477{
473 typedef int refcnt_t; 478 typedef int refcnt_t;
… …
488 // p if not null 493 // p if not null
489 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; } 494 refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
490 495
491 void refcnt_dec () 496 void refcnt_dec ()
492 { 497 {
493 if (!is_constant (p)) 498 if (!ecb_is_constant (p))
494 --*refcnt_ref (); 499 --*refcnt_ref ();
495 else if (p) 500 else if (p)
496 --p->refcnt; 501 --p->refcnt;
497 } 502 }
498 503
499 void refcnt_inc () 504 void refcnt_inc ()
500 { 505 {
501 if (!is_constant (p)) 506 if (!ecb_is_constant (p))
502 ++*refcnt_ref (); 507 ++*refcnt_ref ();
503 else if (p) 508 else if (p)
504 ++p->refcnt; 509 ++p->refcnt;
505 } 510 }
506 511
… …
535typedef refptr<maptile> maptile_ptr; 540typedef refptr<maptile> maptile_ptr;
536typedef refptr<object> object_ptr; 541typedef refptr<object> object_ptr;
537typedef refptr<archetype> arch_ptr; 542typedef refptr<archetype> arch_ptr;
538typedef refptr<client> client_ptr; 543typedef refptr<client> client_ptr;
539typedef refptr<player> player_ptr; 544typedef refptr<player> player_ptr;
545typedef refptr<region> region_ptr;
546
547#define STRHSH_NULL 2166136261
548
549static inline uint32_t
550strhsh (const char *s)
551{
552 // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/)
553 // it is about twice as fast as the one-at-a-time one,
554 // with good distribution.
555 // FNV-1a is faster on many cpus because the multiplication
556 // runs concurrently with the looping logic.
557 // we modify the hash a bit to improve its distribution
558 uint32_t hash = STRHSH_NULL;
559
560 while (*s)
561 hash = (hash ^ *s++) * 16777619U;
562
563 return hash ^ (hash >> 16);
564}
565
566static inline uint32_t
567memhsh (const char *s, size_t len)
568{
569 uint32_t hash = STRHSH_NULL;
570
571 while (len--)
572 hash = (hash ^ *s++) * 16777619U;
573
574 return hash;
575}
540 576
541struct str_hash 577struct str_hash
542{ 578{
543 std::size_t operator ()(const char *s) const 579 std::size_t operator ()(const char *s) const
544 { 580 {
545 unsigned long hash = 0;
546
547 /* use the one-at-a-time hash function, which supposedly is
548 * better than the djb2-like one used by perl5.005, but
549 * certainly is better then the bug used here before.
550 * see http://burtleburtle.net/bob/hash/doobs.html
551 */
552 while (*s)
553 {
554 hash += *s++;
555 hash += hash << 10;
556 hash ^= hash >> 6;
557 }
558
559 hash += hash << 3;
560 hash ^= hash >> 11;
561 hash += hash << 15;
562
563 return hash; 581 return strhsh (s);
564 } 582 }
583
584 std::size_t operator ()(const shstr &s) const
585 {
586 return strhsh (s);
587 }
588
589 typedef ska::power_of_two_hash_policy hash_policy;
565}; 590};
566 591
567struct str_equal 592struct str_equal
568{ 593{
569 bool operator ()(const char *a, const char *b) const 594 bool operator ()(const char *a, const char *b) const
… …
595 } 620 }
596}; 621};
597 622
598// This container blends advantages of linked lists 623// This container blends advantages of linked lists
599// (efficiency) with vectors (random access) by 624// (efficiency) with vectors (random access) by
600// by using an unordered vector and storing the vector 625// using an unordered vector and storing the vector
601// index inside the object. 626// index inside the object.
602// 627//
603// + memory-efficient on most 64 bit archs 628// + memory-efficient on most 64 bit archs
604// + O(1) insert/remove 629// + O(1) insert/remove
605// + free unique (but varying) id for inserted objects 630// + free unique (but varying) id for inserted objects
… …
642 insert (&obj); 667 insert (&obj);
643 } 668 }
644 669
645 void erase (T *obj) 670 void erase (T *obj)
646 { 671 {
647 unsigned int pos = obj->*indexmember; 672 object_vector_index pos = obj->*indexmember;
648 obj->*indexmember = 0; 673 obj->*indexmember = 0;
649 674
650 if (pos < this->size ()) 675 if (pos < this->size ())
651 { 676 {
652 (*this)[pos - 1] = (*this)[this->size () - 1]; 677 (*this)[pos - 1] = (*this)[this->size () - 1];
… …
660 { 685 {
661 erase (&obj); 686 erase (&obj);
662 } 687 }
663}; 688};
664 689
690/////////////////////////////////////////////////////////////////////////////
691
692// something like a vector or stack, but without
693// out of bounds checking
694template<typename T>
695struct fixed_stack
696{
697 T *data;
698 int size;
699 int max;
700
701 fixed_stack ()
702 : size (0), data (0)
703 {
704 }
705
706 fixed_stack (int max)
707 : size (0), max (max)
708 {
709 data = salloc<T> (max);
710 }
711
712 void reset (int new_max)
713 {
714 sfree (data, max);
715 size = 0;
716 max = new_max;
717 data = salloc<T> (max);
718 }
719
720 void free ()
721 {
722 sfree (data, max);
723 data = 0;
724 }
725
726 ~fixed_stack ()
727 {
728 sfree (data, max);
729 }
730
731 T &operator[](int idx)
732 {
733 return data [idx];
734 }
735
736 void push (T v)
737 {
738 data [size++] = v;
739 }
740
741 T &pop ()
742 {
743 return data [--size];
744 }
745
746 T remove (int idx)
747 {
748 T v = data [idx];
749
750 data [idx] = data [--size];
751
752 return v;
753 }
754};
755
756/////////////////////////////////////////////////////////////////////////////
757
665// basically does what strncpy should do, but appends "..." to strings exceeding length 758// basically does what strncpy should do, but appends "..." to strings exceeding length
759// returns the number of bytes actually used (including \0)
666void assign (char *dst, const char *src, int maxlen); 760int assign (char *dst, const char *src, int maxsize);
667 761
668// type-safe version of assign 762// type-safe version of assign
669template<int N> 763template<int N>
670inline void assign (char (&dst)[N], const char *src) 764inline int assign (char (&dst)[N], const char *src)
671{ 765{
672 assign ((char *)&dst, src, N); 766 return assign ((char *)&dst, src, N);
673} 767}
674 768
675typedef double tstamp; 769typedef double tstamp;
676 770
677// return current time as timestamp 771// return current time as timestamp
678tstamp now (); 772tstamp now ();
679 773
680int similar_direction (int a, int b); 774int similar_direction (int a, int b);
681 775
682// like sprintf, but returns a "static" buffer 776// like v?sprintf, but returns a "static" buffer
683const char *format (const char *format, ...); 777char *vformat (const char *format, va_list ap);
778char *format (const char *format, ...) ecb_attribute ((format (printf, 1, 2)));
779
780// safety-check player input which will become object->msg
781bool msg_is_safe (const char *msg);
684 782
685///////////////////////////////////////////////////////////////////////////// 783/////////////////////////////////////////////////////////////////////////////
686// threads, very very thin wrappers around pthreads 784// threads, very very thin wrappers around pthreads
687 785
688struct thread 786struct thread

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