server/include/util.h

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * 
 * Deliantra is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#ifndef UTIL_H__
#define UTIL_H__

//#define PREFER_MALLOC

#if __GNUC__ >= 3
# define is_constant(c)             __builtin_constant_p (c)
# define expect(expr,value)         __builtin_expect ((expr),(value))
# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
#else
# define is_constant(c)             0
# define expect(expr,value)         (expr)
# define prefetch(addr,rw,locality)
#endif

#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
# define decltype(x) typeof(x)
#endif

// put into ifs if you are very sure that the expression
// is mostly true or mosty false. note that these return
// booleans, not the expression.
#define expect_false(expr) expect ((expr) != 0, 0)
#define expect_true(expr)  expect ((expr) != 0, 1)

#include <cstddef>
#include <cmath>
#include <new>
#include <vector>

#include <glib.h>

#include <shstr.h>
#include <traits.h>

// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
#define auto(var,expr) decltype(expr) var = (expr)

// very ugly macro that basicaly declares and initialises a variable
// that is in scope for the next statement only
// works only for stuff that can be assigned 0 and converts to false
// (note: works great for pointers)
// most ugly macro I ever wrote
#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)

// in range including end
#define IN_RANGE_INC(val,beg,end) \
  ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))

// in range excluding end
#define IN_RANGE_EXC(val,beg,end) \
  ((unsigned int)(val) - (unsigned int)(beg) <  (unsigned int)(end) - (unsigned int)(beg))

void fork_abort (const char *msg);

// rationale for using (U) not (T) is to reduce signed/unsigned issues,
// as a is often a constant while b is the variable. it is still a bug, though.
template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
template<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; }

template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }

template<typename T>
static inline T
lerp (T val, T min_in, T max_in, T min_out, T max_out)
{
  return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
}

// lots of stuff taken from FXT

/* Rotate right. This is used in various places for checksumming */
//TODO: that sucks, use a better checksum algo
static inline uint32_t
rotate_right (uint32_t c, uint32_t count = 1)
{
  return (c << (32 - count)) | (c >> count);
}

static inline uint32_t
rotate_left (uint32_t c, uint32_t count = 1)
{
  return (c >> (32 - count)) | (c << count);
}

// Return abs(a-b)
// Both a and b must not have the most significant bit set
static inline uint32_t
upos_abs_diff (uint32_t a, uint32_t b)
{
  long d1 = b - a;
  long d2 = (d1 & (d1 >> 31)) << 1;

  return d1 - d2;               // == (b - d) - (a + d);
}

// Both a and b must not have the most significant bit set
static inline uint32_t
upos_min (uint32_t a, uint32_t b)
{
  int32_t d = b - a;
  d &= d >> 31;
  return a + d;
}

// Both a and b must not have the most significant bit set
static inline uint32_t
upos_max (uint32_t a, uint32_t b)
{
  int32_t d = b - a;
  d &= d >> 31;
  return b - d;
}

// this is much faster than crossfires original algorithm
// on modern cpus
inline int
isqrt (int n)
{
  return (int)sqrtf ((float)n);
}

// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
#if 0
// and has a max. error of 6 in the range -100..+100.
#else
// and has a max. error of 9 in the range -100..+100.
#endif
inline int 
idistance (int dx, int dy)
{ 
  unsigned int dx_ = abs (dx);
  unsigned int dy_ = abs (dy);

#if 0
  return dx_ > dy_
      ? (dx_ * 61685 + dy_ * 26870) >> 16
      : (dy_ * 61685 + dx_ * 26870) >> 16;
#else
  return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
#endif
}

/*
 * absdir(int): Returns a number between 1 and 8, which represent
 * the "absolute" direction of a number (it actually takes care of
 * "overflow" in previous calculations of a direction).
 */
inline int
absdir (int d)
{
  return ((d - 1) & 7) + 1;
}

extern size_t slice_alloc; // statistics

// makes dynamically allocated objects zero-initialised
struct zero_initialised
{
  void *operator new (size_t s, void *p)
  {
    memset (p, 0, s);
    return p;
  }

  void *operator new (size_t s)
  {
    slice_alloc += s;
    return g_slice_alloc0 (s);
  }

  void *operator new[] (size_t s)
  {
    slice_alloc += s;
    return g_slice_alloc0 (s);
  }

  void operator delete (void *p, size_t s)
  {
    slice_alloc -= s;
    g_slice_free1 (s, p);
  }

  void operator delete[] (void *p, size_t s)
  {
    slice_alloc -= s;
    g_slice_free1 (s, p);
  }
};

void *salloc_ (int n)            throw (std::bad_alloc);
void *salloc_ (int n, void *src) throw (std::bad_alloc);

// strictly the same as g_slice_alloc, but never returns 0
template<typename T>
inline T *salloc (int n = 1)     throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T));              }

// also copies src into the new area, like "memdup"
// if src is 0, clears the memory
template<typename T>
inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }

// clears the memory
template<typename T>
inline T *salloc0(int n = 1)     throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0);           }

// for symmetry
template<typename T>
inline void sfree (T *ptr, int n = 1) throw ()
{
#ifdef PREFER_MALLOC
  free (ptr);
#else
  slice_alloc -= n * sizeof (T);
  g_slice_free1 (n * sizeof (T), (void *)ptr);
#endif
}

// a STL-compatible allocator that uses g_slice
// boy, this is verbose
template<typename Tp>
struct slice_allocator
{
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;
  typedef Tp *pointer;
  typedef const Tp *const_pointer;
  typedef Tp &reference;
  typedef const Tp &const_reference;
  typedef Tp value_type;

  template <class U> 
  struct rebind
  {
    typedef slice_allocator<U> other;
  };

  slice_allocator () throw () { }
  slice_allocator (const slice_allocator &o) throw () { }
  template<typename Tp2>
  slice_allocator (const slice_allocator<Tp2> &) throw () { }

  ~slice_allocator () { }

  pointer address (reference x) const { return &x; }
  const_pointer address (const_reference x) const { return &x; }

  pointer allocate (size_type n, const_pointer = 0)
  {
    return salloc<Tp> (n);
  }

  void deallocate (pointer p, size_type n)
  {
    sfree<Tp> (p, n);
  }

  size_type max_size ()const throw ()
  {
    return size_t (-1) / sizeof (Tp);
  }

  void construct (pointer p, const Tp &val)
  {
    ::new (p) Tp (val);
  }

  void destroy (pointer p)
  {
    p->~Tp ();
  }
};

// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
struct tausworthe_random_generator
{
  // generator
  uint32_t state [4];

  void operator =(const tausworthe_random_generator &src)
  {
    state [0] = src.state [0];
    state [1] = src.state [1];
    state [2] = src.state [2];
    state [3] = src.state [3];
  }

  void seed (uint32_t seed);
  uint32_t next ();

  // uniform distribution
  uint32_t operator ()(uint32_t num)
  {
    return is_constant (num)
             ? (next () * (uint64_t)num) >> 32U
             : get_range (num);
  }

  // return a number within (min .. max)
  int operator () (int r_min, int r_max)
  {
    return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
              ? r_min + operator ()(r_max - r_min + 1)
              : get_range (r_min, r_max);
  }

  double operator ()()
  {
    return this->next () / (double)0xFFFFFFFFU;
  }

protected:
  uint32_t get_range (uint32_t r_max);
  int get_range (int r_min, int r_max);
};

typedef tausworthe_random_generator rand_gen;

extern rand_gen rndm;

INTERFACE_CLASS (attachable)
struct refcnt_base
{
  typedef int refcnt_t;
  mutable refcnt_t ACC (RW, refcnt);

  MTH void refcnt_inc () const { ++refcnt; }
  MTH void refcnt_dec () const { --refcnt; }

  refcnt_base () : refcnt (0) { }
};

// to avoid branches with more advanced compilers
extern refcnt_base::refcnt_t refcnt_dummy;

template<class T>
struct refptr
{
  // p if not null
  refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }

  void refcnt_dec ()
  {
    if (!is_constant (p))
      --*refcnt_ref ();
    else if (p)
      --p->refcnt;
  }

  void refcnt_inc ()
  {
    if (!is_constant (p))
      ++*refcnt_ref ();
    else if (p)
      ++p->refcnt;
  }

  T *p;

  refptr () : p(0) { }
  refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
  refptr (T *p) : p(p) { refcnt_inc (); }
  ~refptr () { refcnt_dec (); }

  const refptr<T> &operator =(T *o)
  {
    // if decrementing ever destroys we need to reverse the order here
    refcnt_dec ();
    p = o;
    refcnt_inc ();
    return *this;
  }

  const refptr<T> &operator =(const refptr<T> &o)
  {
    *this = o.p;
    return *this;
  }

  T &operator * () const { return *p; }
  T *operator ->() const { return  p; }

  operator T *() const { return p; }
};

typedef refptr<maptile>   maptile_ptr;
typedef refptr<object>    object_ptr;
typedef refptr<archetype> arch_ptr;
typedef refptr<client>    client_ptr;
typedef refptr<player>    player_ptr;

struct str_hash
{
  std::size_t operator ()(const char *s) const
  {
    unsigned long hash = 0;

    /* use the one-at-a-time hash function, which supposedly is
     * better than the djb2-like one used by perl5.005, but
     * certainly is better then the bug used here before.
     * see http://burtleburtle.net/bob/hash/doobs.html
     */
    while (*s)
      {
        hash += *s++;
        hash += hash << 10;
        hash ^= hash >>  6;
      }

    hash += hash <<  3;
    hash ^= hash >> 11;
    hash += hash << 15;

    return hash;
  }
};

struct str_equal
{
  bool operator ()(const char *a, const char *b) const
  {
    return !strcmp (a, b);
  }
};

// Mostly the same as std::vector, but insert/erase can reorder
// the elements, making append(=insert)/remove O(1) instead of O(n).
//
// NOTE: only some forms of erase are available
template<class T>
struct unordered_vector : std::vector<T, slice_allocator<T> >
{
  typedef typename unordered_vector::iterator iterator;

  void erase (unsigned int pos)
  {
    if (pos < this->size () - 1)
      (*this)[pos] = (*this)[this->size () - 1];

    this->pop_back ();
  }

  void erase (iterator i)
  {
    erase ((unsigned int )(i - this->begin ()));
  }
};

// This container blends advantages of linked lists
// (efficiency) with vectors (random access) by
// by using an unordered vector and storing the vector
// index inside the object.
//
// + memory-efficient on most 64 bit archs
// + O(1) insert/remove
// + free unique (but varying) id for inserted objects
// + cache-friendly iteration
// - only works for pointers to structs
//
// NOTE: only some forms of erase/insert are available
typedef int object_vector_index;

template<class T, object_vector_index T::*indexmember>
struct object_vector : std::vector<T *, slice_allocator<T *> >
{
  typedef typename object_vector::iterator iterator;

  bool contains (const T *obj) const
  {
    return obj->*indexmember;
  }

  iterator find (const T *obj)
  {
    return obj->*indexmember
      ? this->begin () + obj->*indexmember - 1
      : this->end ();
  }

  void push_back (T *obj)
  {
    std::vector<T *, slice_allocator<T *> >::push_back (obj);
    obj->*indexmember = this->size ();
  }

  void insert (T *obj)
  {
    push_back (obj);
  }

  void insert (T &obj)
  {
    insert (&obj);
  }

  void erase (T *obj)
  {
    unsigned int pos = obj->*indexmember;
    obj->*indexmember = 0;

    if (pos < this->size ())
      {
        (*this)[pos - 1] = (*this)[this->size () - 1];
        (*this)[pos - 1]->*indexmember = pos;
      }

    this->pop_back ();
  }

  void erase (T &obj)
  {
    erase (&obj);
  }
};

// basically does what strncpy should do, but appends "..." to strings exceeding length
void assign (char *dst, const char *src, int maxlen);

// type-safe version of assign
template<int N>
inline void assign (char (&dst)[N], const char *src)
{
  assign ((char *)&dst, src, N);
}

typedef double tstamp;

// return current time as timestamp
tstamp now ();

int similar_direction (int a, int b);

// like sprintf, but returns a "static" buffer
const char *format (const char *format, ...);

#endif

Revision:	1.59
Committed:	Sun Dec 16 02:50:33 2007 UTC (16 years, 5 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_4
Changes since 1.58:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.46	/*
2	root	1.58	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	root	1.46	*
4	root	1.58	* Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.46	*
6	root	1.58	* Deliantra is free software: you can redistribute it and/or modify
7	root	1.51	* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation, either version 3 of the License, or
9			* (at your option) any later version.
10	root	1.46	*
11	root	1.51	* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15	root	1.46	*
16	root	1.51	* You should have received a copy of the GNU General Public License
17			* along with this program. If not, see <http://www.gnu.org/licenses/>.
18	root	1.46	*
19	root	1.58	* The authors can be reached via e-mail to <support@deliantra.net>
20	root	1.46	*/
21
22	root	1.1	#ifndef UTIL_H__
23			#define UTIL_H__
24
25	root	1.36	//#define PREFER_MALLOC
26
27	root	1.2	#if __GNUC__ >= 3
28	root	1.45	# define is_constant(c) __builtin_constant_p (c)
29			# define expect(expr,value) __builtin_expect ((expr),(value))
30			# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
31	root	1.2	#else
32	root	1.45	# define is_constant(c) 0
33			# define expect(expr,value) (expr)
34			# define prefetch(addr,rw,locality)
35	root	1.2	#endif
36
37	root	1.47	#if __GNUC__ < 4 \|\| (__GNUC__ == 4 \|\| __GNUC_MINOR__ < 4)
38			# define decltype(x) typeof(x)
39			#endif
40
41	root	1.45	// put into ifs if you are very sure that the expression
42			// is mostly true or mosty false. note that these return
43			// booleans, not the expression.
44			#define expect_false(expr) expect ((expr) != 0, 0)
45			#define expect_true(expr) expect ((expr) != 0, 1)
46
47	root	1.11	#include <cstddef>
48	root	1.28	#include <cmath>
49	root	1.25	#include <new>
50			#include <vector>
51	root	1.11
52			#include <glib.h>
53
54	root	1.25	#include <shstr.h>
55			#include <traits.h>
56
57	root	1.49	// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
58	root	1.47	#define auto(var,expr) decltype(expr) var = (expr)
59	root	1.14
60	root	1.26	// very ugly macro that basicaly declares and initialises a variable
61			// that is in scope for the next statement only
62			// works only for stuff that can be assigned 0 and converts to false
63			// (note: works great for pointers)
64			// most ugly macro I ever wrote
65	root	1.48	#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
66	root	1.26
67	root	1.27	// in range including end
68			#define IN_RANGE_INC(val,beg,end) \
69			((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
70
71			// in range excluding end
72			#define IN_RANGE_EXC(val,beg,end) \
73			((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
74
75	root	1.31	void fork_abort (const char *msg);
76
77	root	1.35	// rationale for using (U) not (T) is to reduce signed/unsigned issues,
78			// as a is often a constant while b is the variable. it is still a bug, though.
79			template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
80			template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
81			template<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; }
82	root	1.32
83			template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
84
85	root	1.44	template<typename T>
86			static inline T
87			lerp (T val, T min_in, T max_in, T min_out, T max_out)
88			{
89			return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
90			}
91
92	root	1.37	// lots of stuff taken from FXT
93
94			/* Rotate right. This is used in various places for checksumming */
95	root	1.38	//TODO: that sucks, use a better checksum algo
96	root	1.37	static inline uint32_t
97	root	1.38	rotate_right (uint32_t c, uint32_t count = 1)
98	root	1.37	{
99	root	1.38	return (c << (32 - count)) \| (c >> count);
100			}
101
102			static inline uint32_t
103			rotate_left (uint32_t c, uint32_t count = 1)
104			{
105			return (c >> (32 - count)) \| (c << count);
106	root	1.37	}
107
108			// Return abs(a-b)
109			// Both a and b must not have the most significant bit set
110			static inline uint32_t
111			upos_abs_diff (uint32_t a, uint32_t b)
112			{
113			long d1 = b - a;
114			long d2 = (d1 & (d1 >> 31)) << 1;
115
116			return d1 - d2; // == (b - d) - (a + d);
117			}
118
119			// Both a and b must not have the most significant bit set
120			static inline uint32_t
121			upos_min (uint32_t a, uint32_t b)
122			{
123			int32_t d = b - a;
124			d &= d >> 31;
125			return a + d;
126			}
127
128			// Both a and b must not have the most significant bit set
129			static inline uint32_t
130			upos_max (uint32_t a, uint32_t b)
131			{
132			int32_t d = b - a;
133			d &= d >> 31;
134			return b - d;
135			}
136
137	root	1.28	// this is much faster than crossfires original algorithm
138			// on modern cpus
139			inline int
140			isqrt (int n)
141			{
142			return (int)sqrtf ((float)n);
143			}
144
145			// this is only twice as fast as naive sqrtf (dxdy+dydy)
146			#if 0
147			// and has a max. error of 6 in the range -100..+100.
148			#else
149			// and has a max. error of 9 in the range -100..+100.
150			#endif
151			inline int
152			idistance (int dx, int dy)
153			{
154			unsigned int dx_ = abs (dx);
155			unsigned int dy_ = abs (dy);
156
157			#if 0
158			return dx_ > dy_
159			? (dx_ * 61685 + dy_ * 26870) >> 16
160			: (dy_ * 61685 + dx_ * 26870) >> 16;
161			#else
162	root	1.30	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
163	root	1.28	#endif
164			}
165
166	root	1.29	/*
167			* absdir(int): Returns a number between 1 and 8, which represent
168			* the "absolute" direction of a number (it actually takes care of
169			* "overflow" in previous calculations of a direction).
170			*/
171			inline int
172			absdir (int d)
173			{
174			return ((d - 1) & 7) + 1;
175			}
176	root	1.28
177	root	1.57	extern size_t slice_alloc; // statistics
178
179	root	1.1	// makes dynamically allocated objects zero-initialised
180			struct zero_initialised
181			{
182	root	1.11	void operator new (size_t s, void p)
183			{
184			memset (p, 0, s);
185			return p;
186			}
187
188			void *operator new (size_t s)
189			{
190	root	1.57	slice_alloc += s;
191	root	1.11	return g_slice_alloc0 (s);
192			}
193
194			void *operator new[] (size_t s)
195			{
196	root	1.57	slice_alloc += s;
197	root	1.11	return g_slice_alloc0 (s);
198			}
199
200			void operator delete (void *p, size_t s)
201			{
202	root	1.57	slice_alloc -= s;
203	root	1.11	g_slice_free1 (s, p);
204			}
205
206			void operator delete[] (void *p, size_t s)
207			{
208	root	1.57	slice_alloc -= s;
209	root	1.11	g_slice_free1 (s, p);
210			}
211			};
212
213	root	1.20	void *salloc_ (int n) throw (std::bad_alloc);
214			void salloc_ (int n, void src) throw (std::bad_alloc);
215
216	root	1.12	// strictly the same as g_slice_alloc, but never returns 0
217	root	1.20	template<typename T>
218			inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
219
220	root	1.17	// also copies src into the new area, like "memdup"
221	root	1.18	// if src is 0, clears the memory
222			template<typename T>
223	root	1.20	inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
224	root	1.18
225	root	1.21	// clears the memory
226			template<typename T>
227			inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
228
229	root	1.12	// for symmetry
230	root	1.18	template<typename T>
231	root	1.20	inline void sfree (T *ptr, int n = 1) throw ()
232	root	1.12	{
233	root	1.36	#ifdef PREFER_MALLOC
234			free (ptr);
235			#else
236	root	1.57	slice_alloc -= n * sizeof (T);
237	root	1.20	g_slice_free1 (n * sizeof (T), (void *)ptr);
238	root	1.36	#endif
239	root	1.12	}
240	root	1.11
241			// a STL-compatible allocator that uses g_slice
242			// boy, this is verbose
243			template<typename Tp>
244			struct slice_allocator
245			{
246			typedef size_t size_type;
247			typedef ptrdiff_t difference_type;
248			typedef Tp *pointer;
249			typedef const Tp *const_pointer;
250			typedef Tp &reference;
251			typedef const Tp &const_reference;
252			typedef Tp value_type;
253
254			template <class U>
255			struct rebind
256			{
257			typedef slice_allocator<U> other;
258			};
259
260			slice_allocator () throw () { }
261			slice_allocator (const slice_allocator &o) throw () { }
262			template<typename Tp2>
263			slice_allocator (const slice_allocator<Tp2> &) throw () { }
264
265			~slice_allocator () { }
266
267			pointer address (reference x) const { return &x; }
268			const_pointer address (const_reference x) const { return &x; }
269
270			pointer allocate (size_type n, const_pointer = 0)
271			{
272	root	1.18	return salloc<Tp> (n);
273	root	1.11	}
274
275			void deallocate (pointer p, size_type n)
276			{
277	root	1.19	sfree<Tp> (p, n);
278	root	1.11	}
279
280			size_type max_size ()const throw ()
281			{
282			return size_t (-1) / sizeof (Tp);
283			}
284
285			void construct (pointer p, const Tp &val)
286			{
287			::new (p) Tp (val);
288			}
289
290			void destroy (pointer p)
291			{
292			p->~Tp ();
293			}
294	root	1.1	};
295
296	root	1.32	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
297			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
298			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
299			struct tausworthe_random_generator
300			{
301	root	1.34	// generator
302	root	1.32	uint32_t state [4];
303
304	root	1.34	void operator =(const tausworthe_random_generator &src)
305			{
306			state [0] = src.state [0];
307			state [1] = src.state [1];
308			state [2] = src.state [2];
309			state [3] = src.state [3];
310			}
311
312			void seed (uint32_t seed);
313	root	1.32	uint32_t next ();
314
315	root	1.34	// uniform distribution
316	root	1.42	uint32_t operator ()(uint32_t num)
317	root	1.32	{
318	root	1.42	return is_constant (num)
319			? (next () * (uint64_t)num) >> 32U
320			: get_range (num);
321	root	1.32	}
322
323			// return a number within (min .. max)
324			int operator () (int r_min, int r_max)
325			{
326	root	1.42	return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
327			? r_min + operator ()(r_max - r_min + 1)
328	root	1.34	: get_range (r_min, r_max);
329	root	1.32	}
330
331			double operator ()()
332			{
333	root	1.34	return this->next () / (double)0xFFFFFFFFU;
334	root	1.32	}
335	root	1.34
336			protected:
337			uint32_t get_range (uint32_t r_max);
338			int get_range (int r_min, int r_max);
339	root	1.32	};
340
341			typedef tausworthe_random_generator rand_gen;
342
343			extern rand_gen rndm;
344
345	root	1.54	INTERFACE_CLASS (attachable)
346			struct refcnt_base
347			{
348			typedef int refcnt_t;
349			mutable refcnt_t ACC (RW, refcnt);
350
351			MTH void refcnt_inc () const { ++refcnt; }
352			MTH void refcnt_dec () const { --refcnt; }
353
354			refcnt_base () : refcnt (0) { }
355			};
356
357	root	1.56	// to avoid branches with more advanced compilers
358	root	1.54	extern refcnt_base::refcnt_t refcnt_dummy;
359
360	root	1.7	template<class T>
361			struct refptr
362			{
363	root	1.54	// p if not null
364			refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
365
366			void refcnt_dec ()
367			{
368			if (!is_constant (p))
369			--*refcnt_ref ();
370			else if (p)
371			--p->refcnt;
372			}
373
374			void refcnt_inc ()
375			{
376			if (!is_constant (p))
377			++*refcnt_ref ();
378			else if (p)
379			++p->refcnt;
380			}
381
382	root	1.7	T *p;
383
384			refptr () : p(0) { }
385	root	1.54	refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
386			refptr (T *p) : p(p) { refcnt_inc (); }
387			~refptr () { refcnt_dec (); }
388	root	1.7
389			const refptr<T> &operator =(T *o)
390			{
391	root	1.54	// if decrementing ever destroys we need to reverse the order here
392			refcnt_dec ();
393	root	1.7	p = o;
394	root	1.54	refcnt_inc ();
395	root	1.7	return *this;
396			}
397
398	root	1.54	const refptr<T> &operator =(const refptr<T> &o)
399	root	1.7	{
400			*this = o.p;
401			return *this;
402			}
403
404			T &operator * () const { return *p; }
405	root	1.54	T *operator ->() const { return p; }
406	root	1.7
407			operator T *() const { return p; }
408			};
409
410	root	1.24	typedef refptr<maptile> maptile_ptr;
411	root	1.22	typedef refptr<object> object_ptr;
412			typedef refptr<archetype> arch_ptr;
413	root	1.24	typedef refptr<client> client_ptr;
414			typedef refptr<player> player_ptr;
415	root	1.22
416	root	1.4	struct str_hash
417			{
418			std::size_t operator ()(const char *s) const
419			{
420			unsigned long hash = 0;
421
422			/* use the one-at-a-time hash function, which supposedly is
423			* better than the djb2-like one used by perl5.005, but
424			* certainly is better then the bug used here before.
425			* see http://burtleburtle.net/bob/hash/doobs.html
426			*/
427			while (*s)
428			{
429			hash += *s++;
430			hash += hash << 10;
431			hash ^= hash >> 6;
432			}
433
434			hash += hash << 3;
435			hash ^= hash >> 11;
436			hash += hash << 15;
437
438			return hash;
439			}
440			};
441
442			struct str_equal
443			{
444			bool operator ()(const char a, const char b) const
445			{
446			return !strcmp (a, b);
447			}
448			};
449
450	root	1.49	// Mostly the same as std::vector, but insert/erase can reorder
451	root	1.52	// the elements, making append(=insert)/remove O(1) instead of O(n).
452	root	1.49	//
453	root	1.52	// NOTE: only some forms of erase are available
454	root	1.26	template<class T>
455			struct unordered_vector : std::vector<T, slice_allocator<T> >
456	root	1.6	{
457	root	1.11	typedef typename unordered_vector::iterator iterator;
458	root	1.6
459			void erase (unsigned int pos)
460			{
461			if (pos < this->size () - 1)
462			(this)[pos] = (this)[this->size () - 1];
463
464			this->pop_back ();
465			}
466
467			void erase (iterator i)
468			{
469			erase ((unsigned int )(i - this->begin ()));
470			}
471			};
472
473	root	1.49	// This container blends advantages of linked lists
474			// (efficiency) with vectors (random access) by
475			// by using an unordered vector and storing the vector
476			// index inside the object.
477			//
478			// + memory-efficient on most 64 bit archs
479			// + O(1) insert/remove
480			// + free unique (but varying) id for inserted objects
481			// + cache-friendly iteration
482			// - only works for pointers to structs
483			//
484			// NOTE: only some forms of erase/insert are available
485	root	1.50	typedef int object_vector_index;
486
487			template<class T, object_vector_index T::*indexmember>
488	root	1.26	struct object_vector : std::vector<T , slice_allocator<T > >
489			{
490	root	1.48	typedef typename object_vector::iterator iterator;
491
492			bool contains (const T *obj) const
493			{
494	root	1.50	return obj->*indexmember;
495	root	1.48	}
496
497			iterator find (const T *obj)
498			{
499	root	1.50	return obj->*indexmember
500			? this->begin () + obj->*indexmember - 1
501	root	1.48	: this->end ();
502			}
503
504	root	1.53	void push_back (T *obj)
505			{
506			std::vector<T , slice_allocator<T > >::push_back (obj);
507			obj->*indexmember = this->size ();
508			}
509
510	root	1.26	void insert (T *obj)
511			{
512			push_back (obj);
513			}
514
515			void insert (T &obj)
516			{
517			insert (&obj);
518			}
519
520			void erase (T *obj)
521			{
522	root	1.50	unsigned int pos = obj->*indexmember;
523			obj->*indexmember = 0;
524	root	1.26
525			if (pos < this->size ())
526			{
527			(this)[pos - 1] = (this)[this->size () - 1];
528	root	1.50	(this)[pos - 1]->indexmember = pos;
529	root	1.26	}
530
531			this->pop_back ();
532			}
533
534			void erase (T &obj)
535			{
536	root	1.50	erase (&obj);
537	root	1.26	}
538			};
539
540	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
541			void assign (char dst, const char src, int maxlen);
542
543			// type-safe version of assign
544	root	1.9	template<int N>
545			inline void assign (char (&dst)[N], const char *src)
546			{
547	root	1.10	assign ((char *)&dst, src, N);
548	root	1.9	}
549
550	root	1.17	typedef double tstamp;
551
552	root	1.59	// return current time as timestamp
553	root	1.17	tstamp now ();
554
555	root	1.25	int similar_direction (int a, int b);
556
557	root	1.55	// like sprintf, but returns a "static" buffer
558			const char format (const char format, ...);
559	root	1.43
560	root	1.1	#endif
561