server/include/util.h

/*
 * This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
 * 
 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
 * 
 * Crossfire TRT 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 2 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 Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 * 
 * The authors can be reached via e-mail to <crossfire@schmorp.de>
 */

#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;
}

// 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)
  {
    return g_slice_alloc0 (s);
  }

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

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

  void operator delete[] (void *p, size_t 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
  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;

template<class T>
struct refptr
{
  T *p;

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

  const refptr<T> &operator =(T *o)
  {
    if (p) p->refcnt_dec ();
    p = o;
    if (p) p->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 insret/remove O(1) instead of O(n).
//
// NOTE: only some forms of erase/insert 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 insert (T *obj)
  {
    push_back (obj);
    obj->*indexmember = this->size ();
  }

  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 timestampe
tstamp now ();

int similar_direction (int a, int b);

// like printf, but returns a std::string
const std::string format (const char *format, ...);

#endif

Revision:	1.50
Committed:	Sun Jun 24 00:33:54 2007 UTC (16 years, 11 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.49:	+11 -9 lines
Log Message:	- pippijn unknowingly inspired the idea of documenting the type of the objetc_vector_index explicitly. - pippijn spotted a typoe, to, go figure!
#	User	Rev	Content
1	root	1.46	/*
2			* This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
3			*
4			* Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
5			*
6			* Crossfire TRT is free software; you can redistribute it and/or modify it
7			* under the terms of the GNU General Public License as published by the Free
8			* Software Foundation; either version 2 of the License, or (at your option)
9			* any later version.
10			*
11			* This program is distributed in the hope that it will be useful, but
12			* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13			* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14			* for more details.
15			*
16			* You should have received a copy of the GNU General Public License along
17			* with Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
18			* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19			*
20			* The authors can be reached via e-mail to <crossfire@schmorp.de>
21			*/
22
23	root	1.1	#ifndef UTIL_H__
24			#define UTIL_H__
25
26	root	1.36	//#define PREFER_MALLOC
27
28	root	1.2	#if __GNUC__ >= 3
29	root	1.45	# define is_constant(c) __builtin_constant_p (c)
30			# define expect(expr,value) __builtin_expect ((expr),(value))
31			# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
32	root	1.2	#else
33	root	1.45	# define is_constant(c) 0
34			# define expect(expr,value) (expr)
35			# define prefetch(addr,rw,locality)
36	root	1.2	#endif
37
38	root	1.47	#if __GNUC__ < 4 \|\| (__GNUC__ == 4 \|\| __GNUC_MINOR__ < 4)
39			# define decltype(x) typeof(x)
40			#endif
41
42	root	1.45	// put into ifs if you are very sure that the expression
43			// is mostly true or mosty false. note that these return
44			// booleans, not the expression.
45			#define expect_false(expr) expect ((expr) != 0, 0)
46			#define expect_true(expr) expect ((expr) != 0, 1)
47
48	root	1.11	#include <cstddef>
49	root	1.28	#include <cmath>
50	root	1.25	#include <new>
51			#include <vector>
52	root	1.11
53			#include <glib.h>
54
55	root	1.25	#include <shstr.h>
56			#include <traits.h>
57
58	root	1.49	// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
59	root	1.47	#define auto(var,expr) decltype(expr) var = (expr)
60	root	1.14
61	root	1.26	// very ugly macro that basicaly declares and initialises a variable
62			// that is in scope for the next statement only
63			// works only for stuff that can be assigned 0 and converts to false
64			// (note: works great for pointers)
65			// most ugly macro I ever wrote
66	root	1.48	#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
67	root	1.26
68	root	1.27	// in range including end
69			#define IN_RANGE_INC(val,beg,end) \
70			((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
71
72			// in range excluding end
73			#define IN_RANGE_EXC(val,beg,end) \
74			((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
75
76	root	1.31	void fork_abort (const char *msg);
77
78	root	1.35	// rationale for using (U) not (T) is to reduce signed/unsigned issues,
79			// as a is often a constant while b is the variable. it is still a bug, though.
80			template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
81			template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
82			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; }
83	root	1.32
84			template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
85
86	root	1.44	template<typename T>
87			static inline T
88			lerp (T val, T min_in, T max_in, T min_out, T max_out)
89			{
90			return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
91			}
92
93	root	1.37	// lots of stuff taken from FXT
94
95			/* Rotate right. This is used in various places for checksumming */
96	root	1.38	//TODO: that sucks, use a better checksum algo
97	root	1.37	static inline uint32_t
98	root	1.38	rotate_right (uint32_t c, uint32_t count = 1)
99	root	1.37	{
100	root	1.38	return (c << (32 - count)) \| (c >> count);
101			}
102
103			static inline uint32_t
104			rotate_left (uint32_t c, uint32_t count = 1)
105			{
106			return (c >> (32 - count)) \| (c << count);
107	root	1.37	}
108
109			// Return abs(a-b)
110			// Both a and b must not have the most significant bit set
111			static inline uint32_t
112			upos_abs_diff (uint32_t a, uint32_t b)
113			{
114			long d1 = b - a;
115			long d2 = (d1 & (d1 >> 31)) << 1;
116
117			return d1 - d2; // == (b - d) - (a + d);
118			}
119
120			// Both a and b must not have the most significant bit set
121			static inline uint32_t
122			upos_min (uint32_t a, uint32_t b)
123			{
124			int32_t d = b - a;
125			d &= d >> 31;
126			return a + d;
127			}
128
129			// Both a and b must not have the most significant bit set
130			static inline uint32_t
131			upos_max (uint32_t a, uint32_t b)
132			{
133			int32_t d = b - a;
134			d &= d >> 31;
135			return b - d;
136			}
137
138	root	1.28	// this is much faster than crossfires original algorithm
139			// on modern cpus
140			inline int
141			isqrt (int n)
142			{
143			return (int)sqrtf ((float)n);
144			}
145
146			// this is only twice as fast as naive sqrtf (dxdy+dydy)
147			#if 0
148			// and has a max. error of 6 in the range -100..+100.
149			#else
150			// and has a max. error of 9 in the range -100..+100.
151			#endif
152			inline int
153			idistance (int dx, int dy)
154			{
155			unsigned int dx_ = abs (dx);
156			unsigned int dy_ = abs (dy);
157
158			#if 0
159			return dx_ > dy_
160			? (dx_ * 61685 + dy_ * 26870) >> 16
161			: (dy_ * 61685 + dx_ * 26870) >> 16;
162			#else
163	root	1.30	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
164	root	1.28	#endif
165			}
166
167	root	1.29	/*
168			* absdir(int): Returns a number between 1 and 8, which represent
169			* the "absolute" direction of a number (it actually takes care of
170			* "overflow" in previous calculations of a direction).
171			*/
172			inline int
173			absdir (int d)
174			{
175			return ((d - 1) & 7) + 1;
176			}
177	root	1.28
178	root	1.1	// makes dynamically allocated objects zero-initialised
179			struct zero_initialised
180			{
181	root	1.11	void operator new (size_t s, void p)
182			{
183			memset (p, 0, s);
184			return p;
185			}
186
187			void *operator new (size_t s)
188			{
189			return g_slice_alloc0 (s);
190			}
191
192			void *operator new[] (size_t s)
193			{
194			return g_slice_alloc0 (s);
195			}
196
197			void operator delete (void *p, size_t s)
198			{
199			g_slice_free1 (s, p);
200			}
201
202			void operator delete[] (void *p, size_t s)
203			{
204			g_slice_free1 (s, p);
205			}
206			};
207
208	root	1.20	void *salloc_ (int n) throw (std::bad_alloc);
209			void salloc_ (int n, void src) throw (std::bad_alloc);
210
211	root	1.12	// strictly the same as g_slice_alloc, but never returns 0
212	root	1.20	template<typename T>
213			inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
214
215	root	1.17	// also copies src into the new area, like "memdup"
216	root	1.18	// if src is 0, clears the memory
217			template<typename T>
218	root	1.20	inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
219	root	1.18
220	root	1.21	// clears the memory
221			template<typename T>
222			inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
223
224	root	1.12	// for symmetry
225	root	1.18	template<typename T>
226	root	1.20	inline void sfree (T *ptr, int n = 1) throw ()
227	root	1.12	{
228	root	1.36	#ifdef PREFER_MALLOC
229			free (ptr);
230			#else
231	root	1.20	g_slice_free1 (n * sizeof (T), (void *)ptr);
232	root	1.36	#endif
233	root	1.12	}
234	root	1.11
235			// a STL-compatible allocator that uses g_slice
236			// boy, this is verbose
237			template<typename Tp>
238			struct slice_allocator
239			{
240			typedef size_t size_type;
241			typedef ptrdiff_t difference_type;
242			typedef Tp *pointer;
243			typedef const Tp *const_pointer;
244			typedef Tp &reference;
245			typedef const Tp &const_reference;
246			typedef Tp value_type;
247
248			template <class U>
249			struct rebind
250			{
251			typedef slice_allocator<U> other;
252			};
253
254			slice_allocator () throw () { }
255			slice_allocator (const slice_allocator &o) throw () { }
256			template<typename Tp2>
257			slice_allocator (const slice_allocator<Tp2> &) throw () { }
258
259			~slice_allocator () { }
260
261			pointer address (reference x) const { return &x; }
262			const_pointer address (const_reference x) const { return &x; }
263
264			pointer allocate (size_type n, const_pointer = 0)
265			{
266	root	1.18	return salloc<Tp> (n);
267	root	1.11	}
268
269			void deallocate (pointer p, size_type n)
270			{
271	root	1.19	sfree<Tp> (p, n);
272	root	1.11	}
273
274			size_type max_size ()const throw ()
275			{
276			return size_t (-1) / sizeof (Tp);
277			}
278
279			void construct (pointer p, const Tp &val)
280			{
281			::new (p) Tp (val);
282			}
283
284			void destroy (pointer p)
285			{
286			p->~Tp ();
287			}
288	root	1.1	};
289
290	root	1.32	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
291			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
292			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
293			struct tausworthe_random_generator
294			{
295	root	1.34	// generator
296	root	1.32	uint32_t state [4];
297
298	root	1.34	void operator =(const tausworthe_random_generator &src)
299			{
300			state [0] = src.state [0];
301			state [1] = src.state [1];
302			state [2] = src.state [2];
303			state [3] = src.state [3];
304			}
305
306			void seed (uint32_t seed);
307	root	1.32	uint32_t next ();
308
309	root	1.34	// uniform distribution
310	root	1.42	uint32_t operator ()(uint32_t num)
311	root	1.32	{
312	root	1.42	return is_constant (num)
313			? (next () * (uint64_t)num) >> 32U
314			: get_range (num);
315	root	1.32	}
316
317			// return a number within (min .. max)
318			int operator () (int r_min, int r_max)
319			{
320	root	1.42	return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
321			? r_min + operator ()(r_max - r_min + 1)
322	root	1.34	: get_range (r_min, r_max);
323	root	1.32	}
324
325			double operator ()()
326			{
327	root	1.34	return this->next () / (double)0xFFFFFFFFU;
328	root	1.32	}
329	root	1.34
330			protected:
331			uint32_t get_range (uint32_t r_max);
332			int get_range (int r_min, int r_max);
333	root	1.32	};
334
335			typedef tausworthe_random_generator rand_gen;
336
337			extern rand_gen rndm;
338
339	root	1.7	template<class T>
340			struct refptr
341			{
342			T *p;
343
344			refptr () : p(0) { }
345			refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); }
346			refptr (T *p) : p(p) { if (p) p->refcnt_inc (); }
347			~refptr () { if (p) p->refcnt_dec (); }
348
349			const refptr<T> &operator =(T *o)
350			{
351			if (p) p->refcnt_dec ();
352			p = o;
353			if (p) p->refcnt_inc ();
354
355			return *this;
356			}
357
358			const refptr<T> &operator =(const refptr<T> o)
359			{
360			*this = o.p;
361			return *this;
362			}
363
364			T &operator * () const { return *p; }
365			T *operator ->() const { return p; }
366
367			operator T *() const { return p; }
368			};
369
370	root	1.24	typedef refptr<maptile> maptile_ptr;
371	root	1.22	typedef refptr<object> object_ptr;
372			typedef refptr<archetype> arch_ptr;
373	root	1.24	typedef refptr<client> client_ptr;
374			typedef refptr<player> player_ptr;
375	root	1.22
376	root	1.4	struct str_hash
377			{
378			std::size_t operator ()(const char *s) const
379			{
380			unsigned long hash = 0;
381
382			/* use the one-at-a-time hash function, which supposedly is
383			* better than the djb2-like one used by perl5.005, but
384			* certainly is better then the bug used here before.
385			* see http://burtleburtle.net/bob/hash/doobs.html
386			*/
387			while (*s)
388			{
389			hash += *s++;
390			hash += hash << 10;
391			hash ^= hash >> 6;
392			}
393
394			hash += hash << 3;
395			hash ^= hash >> 11;
396			hash += hash << 15;
397
398			return hash;
399			}
400			};
401
402			struct str_equal
403			{
404			bool operator ()(const char a, const char b) const
405			{
406			return !strcmp (a, b);
407			}
408			};
409
410	root	1.49	// Mostly the same as std::vector, but insert/erase can reorder
411			// the elements, making insret/remove O(1) instead of O(n).
412			//
413			// NOTE: only some forms of erase/insert are available
414	root	1.26	template<class T>
415			struct unordered_vector : std::vector<T, slice_allocator<T> >
416	root	1.6	{
417	root	1.11	typedef typename unordered_vector::iterator iterator;
418	root	1.6
419			void erase (unsigned int pos)
420			{
421			if (pos < this->size () - 1)
422			(this)[pos] = (this)[this->size () - 1];
423
424			this->pop_back ();
425			}
426
427			void erase (iterator i)
428			{
429			erase ((unsigned int )(i - this->begin ()));
430			}
431			};
432
433	root	1.49	// This container blends advantages of linked lists
434			// (efficiency) with vectors (random access) by
435			// by using an unordered vector and storing the vector
436			// index inside the object.
437			//
438			// + memory-efficient on most 64 bit archs
439			// + O(1) insert/remove
440			// + free unique (but varying) id for inserted objects
441			// + cache-friendly iteration
442			// - only works for pointers to structs
443			//
444			// NOTE: only some forms of erase/insert are available
445	root	1.50	typedef int object_vector_index;
446
447			template<class T, object_vector_index T::*indexmember>
448	root	1.26	struct object_vector : std::vector<T , slice_allocator<T > >
449			{
450	root	1.48	typedef typename object_vector::iterator iterator;
451
452			bool contains (const T *obj) const
453			{
454	root	1.50	return obj->*indexmember;
455	root	1.48	}
456
457			iterator find (const T *obj)
458			{
459	root	1.50	return obj->*indexmember
460			? this->begin () + obj->*indexmember - 1
461	root	1.48	: this->end ();
462			}
463
464	root	1.26	void insert (T *obj)
465			{
466			push_back (obj);
467	root	1.50	obj->*indexmember = this->size ();
468	root	1.26	}
469
470			void insert (T &obj)
471			{
472			insert (&obj);
473			}
474
475			void erase (T *obj)
476			{
477	root	1.50	unsigned int pos = obj->*indexmember;
478			obj->*indexmember = 0;
479	root	1.26
480			if (pos < this->size ())
481			{
482			(this)[pos - 1] = (this)[this->size () - 1];
483	root	1.50	(this)[pos - 1]->indexmember = pos;
484	root	1.26	}
485
486			this->pop_back ();
487			}
488
489			void erase (T &obj)
490			{
491	root	1.50	erase (&obj);
492	root	1.26	}
493			};
494
495	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
496			void assign (char dst, const char src, int maxlen);
497
498			// type-safe version of assign
499	root	1.9	template<int N>
500			inline void assign (char (&dst)[N], const char *src)
501			{
502	root	1.10	assign ((char *)&dst, src, N);
503	root	1.9	}
504
505	root	1.17	typedef double tstamp;
506
507			// return current time as timestampe
508			tstamp now ();
509
510	root	1.25	int similar_direction (int a, int b);
511
512	root	1.43	// like printf, but returns a std::string
513			const std::string format (const char *format, ...);
514
515	root	1.1	#endif
516