server/include/util.h

#ifndef UTIL_H__
#define UTIL_H__

//#define PREFER_MALLOC

#if __GNUC__ >= 3
# define is_constant(c) __builtin_constant_p (c)
#else
# define is_constant(c) 0
#endif

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

#include <glib.h>

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

// use a gcc extension for auto declarations until ISO C++ sanctifies them
#define AUTODECL(var,expr) typeof(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 declvar(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; }

// lots of stuff taken from FXT

/* Rotate right. This is used in various places for checksumming */
//TODO: this sucks, use a better checksum algo
static inline uint32_t
rotate_right (uint32_t c)
{
  return (c << 31) | (c >> 1);
}

// 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 r_max)
  {
    return is_constant (r_max)
             ? this->next () % r_max
             : get_range (r_max);
  }

  // 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 + (*this) (max (r_max - r_min + 1, 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);
  }
};

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 ()));
  }
};

template<class T, int T::* index>
struct object_vector : std::vector<T *, slice_allocator<T *> >
{
  void insert (T *obj)
  {
    assert (!(obj->*index));
    push_back (obj);
    obj->*index = this->size ();
  }

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

  void erase (T *obj)
  {
    assert (obj->*index);
    int pos = obj->*index;
    obj->*index = 0;

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

    this->pop_back ();
  }

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

#endif

Revision:	1.37
Committed:	Thu Feb 15 15:43:36 2007 UTC (17 years, 3 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.36:	+39 -0 lines
Log Message:	- useless µ-opts - use maximum norm in get_rangevector (a bit, should use more)
#	User	Rev	Content
1	root	1.1	#ifndef UTIL_H__
2			#define UTIL_H__
3
4	root	1.36	//#define PREFER_MALLOC
5
6	root	1.2	#if __GNUC__ >= 3
7			# define is_constant(c) __builtin_constant_p (c)
8			#else
9			# define is_constant(c) 0
10			#endif
11
12	root	1.11	#include <cstddef>
13	root	1.28	#include <cmath>
14	root	1.25	#include <new>
15			#include <vector>
16	root	1.11
17			#include <glib.h>
18
19	root	1.25	#include <shstr.h>
20			#include <traits.h>
21
22	root	1.14	// use a gcc extension for auto declarations until ISO C++ sanctifies them
23			#define AUTODECL(var,expr) typeof(expr) var = (expr)
24
25	root	1.26	// very ugly macro that basicaly declares and initialises a variable
26			// that is in scope for the next statement only
27			// works only for stuff that can be assigned 0 and converts to false
28			// (note: works great for pointers)
29			// most ugly macro I ever wrote
30			#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
31
32	root	1.27	// in range including end
33			#define IN_RANGE_INC(val,beg,end) \
34			((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
35
36			// in range excluding end
37			#define IN_RANGE_EXC(val,beg,end) \
38			((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
39
40	root	1.31	void fork_abort (const char *msg);
41
42	root	1.35	// rationale for using (U) not (T) is to reduce signed/unsigned issues,
43			// as a is often a constant while b is the variable. it is still a bug, though.
44			template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
45			template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
46			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; }
47	root	1.32
48			template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
49
50	root	1.37	// lots of stuff taken from FXT
51
52			/* Rotate right. This is used in various places for checksumming */
53			//TODO: this sucks, use a better checksum algo
54			static inline uint32_t
55			rotate_right (uint32_t c)
56			{
57			return (c << 31) \| (c >> 1);
58			}
59
60			// Return abs(a-b)
61			// Both a and b must not have the most significant bit set
62			static inline uint32_t
63			upos_abs_diff (uint32_t a, uint32_t b)
64			{
65			long d1 = b - a;
66			long d2 = (d1 & (d1 >> 31)) << 1;
67
68			return d1 - d2; // == (b - d) - (a + d);
69			}
70
71			// Both a and b must not have the most significant bit set
72			static inline uint32_t
73			upos_min (uint32_t a, uint32_t b)
74			{
75			int32_t d = b - a;
76			d &= d >> 31;
77			return a + d;
78			}
79
80			// Both a and b must not have the most significant bit set
81			static inline uint32_t
82			upos_max (uint32_t a, uint32_t b)
83			{
84			int32_t d = b - a;
85			d &= d >> 31;
86			return b - d;
87			}
88
89	root	1.28	// this is much faster than crossfires original algorithm
90			// on modern cpus
91			inline int
92			isqrt (int n)
93			{
94			return (int)sqrtf ((float)n);
95			}
96
97			// this is only twice as fast as naive sqrtf (dxdy+dydy)
98			#if 0
99			// and has a max. error of 6 in the range -100..+100.
100			#else
101			// and has a max. error of 9 in the range -100..+100.
102			#endif
103			inline int
104			idistance (int dx, int dy)
105			{
106			unsigned int dx_ = abs (dx);
107			unsigned int dy_ = abs (dy);
108
109			#if 0
110			return dx_ > dy_
111			? (dx_ * 61685 + dy_ * 26870) >> 16
112			: (dy_ * 61685 + dx_ * 26870) >> 16;
113			#else
114	root	1.30	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
115	root	1.28	#endif
116			}
117
118	root	1.29	/*
119			* absdir(int): Returns a number between 1 and 8, which represent
120			* the "absolute" direction of a number (it actually takes care of
121			* "overflow" in previous calculations of a direction).
122			*/
123			inline int
124			absdir (int d)
125			{
126			return ((d - 1) & 7) + 1;
127			}
128	root	1.28
129	root	1.1	// makes dynamically allocated objects zero-initialised
130			struct zero_initialised
131			{
132	root	1.11	void operator new (size_t s, void p)
133			{
134			memset (p, 0, s);
135			return p;
136			}
137
138			void *operator new (size_t s)
139			{
140			return g_slice_alloc0 (s);
141			}
142
143			void *operator new[] (size_t s)
144			{
145			return g_slice_alloc0 (s);
146			}
147
148			void operator delete (void *p, size_t s)
149			{
150			g_slice_free1 (s, p);
151			}
152
153			void operator delete[] (void *p, size_t s)
154			{
155			g_slice_free1 (s, p);
156			}
157			};
158
159	root	1.20	void *salloc_ (int n) throw (std::bad_alloc);
160			void salloc_ (int n, void src) throw (std::bad_alloc);
161
162	root	1.12	// strictly the same as g_slice_alloc, but never returns 0
163	root	1.20	template<typename T>
164			inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
165
166	root	1.17	// also copies src into the new area, like "memdup"
167	root	1.18	// if src is 0, clears the memory
168			template<typename T>
169	root	1.20	inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
170	root	1.18
171	root	1.21	// clears the memory
172			template<typename T>
173			inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
174
175	root	1.12	// for symmetry
176	root	1.18	template<typename T>
177	root	1.20	inline void sfree (T *ptr, int n = 1) throw ()
178	root	1.12	{
179	root	1.36	#ifdef PREFER_MALLOC
180			free (ptr);
181			#else
182	root	1.20	g_slice_free1 (n * sizeof (T), (void *)ptr);
183	root	1.36	#endif
184	root	1.12	}
185	root	1.11
186			// a STL-compatible allocator that uses g_slice
187			// boy, this is verbose
188			template<typename Tp>
189			struct slice_allocator
190			{
191			typedef size_t size_type;
192			typedef ptrdiff_t difference_type;
193			typedef Tp *pointer;
194			typedef const Tp *const_pointer;
195			typedef Tp &reference;
196			typedef const Tp &const_reference;
197			typedef Tp value_type;
198
199			template <class U>
200			struct rebind
201			{
202			typedef slice_allocator<U> other;
203			};
204
205			slice_allocator () throw () { }
206			slice_allocator (const slice_allocator &o) throw () { }
207			template<typename Tp2>
208			slice_allocator (const slice_allocator<Tp2> &) throw () { }
209
210			~slice_allocator () { }
211
212			pointer address (reference x) const { return &x; }
213			const_pointer address (const_reference x) const { return &x; }
214
215			pointer allocate (size_type n, const_pointer = 0)
216			{
217	root	1.18	return salloc<Tp> (n);
218	root	1.11	}
219
220			void deallocate (pointer p, size_type n)
221			{
222	root	1.19	sfree<Tp> (p, n);
223	root	1.11	}
224
225			size_type max_size ()const throw ()
226			{
227			return size_t (-1) / sizeof (Tp);
228			}
229
230			void construct (pointer p, const Tp &val)
231			{
232			::new (p) Tp (val);
233			}
234
235			void destroy (pointer p)
236			{
237			p->~Tp ();
238			}
239	root	1.1	};
240
241	root	1.32	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
242			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
243			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
244			struct tausworthe_random_generator
245			{
246	root	1.34	// generator
247	root	1.32	uint32_t state [4];
248
249	root	1.34	void operator =(const tausworthe_random_generator &src)
250			{
251			state [0] = src.state [0];
252			state [1] = src.state [1];
253			state [2] = src.state [2];
254			state [3] = src.state [3];
255			}
256
257			void seed (uint32_t seed);
258	root	1.32	uint32_t next ();
259
260	root	1.34	// uniform distribution
261	root	1.32	uint32_t operator ()(uint32_t r_max)
262			{
263	root	1.34	return is_constant (r_max)
264			? this->next () % r_max
265			: get_range (r_max);
266	root	1.32	}
267
268			// return a number within (min .. max)
269			int operator () (int r_min, int r_max)
270			{
271	root	1.34	return is_constant (r_min) && is_constant (r_max)
272			? r_min + (*this) (max (r_max - r_min + 1, 1))
273			: get_range (r_min, r_max);
274	root	1.32	}
275
276			double operator ()()
277			{
278	root	1.34	return this->next () / (double)0xFFFFFFFFU;
279	root	1.32	}
280	root	1.34
281			protected:
282			uint32_t get_range (uint32_t r_max);
283			int get_range (int r_min, int r_max);
284	root	1.32	};
285
286			typedef tausworthe_random_generator rand_gen;
287
288			extern rand_gen rndm;
289
290	root	1.7	template<class T>
291			struct refptr
292			{
293			T *p;
294
295			refptr () : p(0) { }
296			refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); }
297			refptr (T *p) : p(p) { if (p) p->refcnt_inc (); }
298			~refptr () { if (p) p->refcnt_dec (); }
299
300			const refptr<T> &operator =(T *o)
301			{
302			if (p) p->refcnt_dec ();
303			p = o;
304			if (p) p->refcnt_inc ();
305
306			return *this;
307			}
308
309			const refptr<T> &operator =(const refptr<T> o)
310			{
311			*this = o.p;
312			return *this;
313			}
314
315			T &operator * () const { return *p; }
316			T *operator ->() const { return p; }
317
318			operator T *() const { return p; }
319			};
320
321	root	1.24	typedef refptr<maptile> maptile_ptr;
322	root	1.22	typedef refptr<object> object_ptr;
323			typedef refptr<archetype> arch_ptr;
324	root	1.24	typedef refptr<client> client_ptr;
325			typedef refptr<player> player_ptr;
326	root	1.22
327	root	1.4	struct str_hash
328			{
329			std::size_t operator ()(const char *s) const
330			{
331			unsigned long hash = 0;
332
333			/* use the one-at-a-time hash function, which supposedly is
334			* better than the djb2-like one used by perl5.005, but
335			* certainly is better then the bug used here before.
336			* see http://burtleburtle.net/bob/hash/doobs.html
337			*/
338			while (*s)
339			{
340			hash += *s++;
341			hash += hash << 10;
342			hash ^= hash >> 6;
343			}
344
345			hash += hash << 3;
346			hash ^= hash >> 11;
347			hash += hash << 15;
348
349			return hash;
350			}
351			};
352
353			struct str_equal
354			{
355			bool operator ()(const char a, const char b) const
356			{
357			return !strcmp (a, b);
358			}
359			};
360
361	root	1.26	template<class T>
362			struct unordered_vector : std::vector<T, slice_allocator<T> >
363	root	1.6	{
364	root	1.11	typedef typename unordered_vector::iterator iterator;
365	root	1.6
366			void erase (unsigned int pos)
367			{
368			if (pos < this->size () - 1)
369			(this)[pos] = (this)[this->size () - 1];
370
371			this->pop_back ();
372			}
373
374			void erase (iterator i)
375			{
376			erase ((unsigned int )(i - this->begin ()));
377			}
378			};
379
380	root	1.26	template<class T, int T::* index>
381			struct object_vector : std::vector<T , slice_allocator<T > >
382			{
383			void insert (T *obj)
384			{
385			assert (!(obj->*index));
386			push_back (obj);
387			obj->*index = this->size ();
388			}
389
390			void insert (T &obj)
391			{
392			insert (&obj);
393			}
394
395			void erase (T *obj)
396			{
397			assert (obj->*index);
398			int pos = obj->*index;
399			obj->*index = 0;
400
401			if (pos < this->size ())
402			{
403			(this)[pos - 1] = (this)[this->size () - 1];
404			(this)[pos - 1]->index = pos;
405			}
406
407			this->pop_back ();
408			}
409
410			void erase (T &obj)
411			{
412			errase (&obj);
413			}
414			};
415
416	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
417			void assign (char dst, const char src, int maxlen);
418
419			// type-safe version of assign
420	root	1.9	template<int N>
421			inline void assign (char (&dst)[N], const char *src)
422			{
423	root	1.10	assign ((char *)&dst, src, N);
424	root	1.9	}
425
426	root	1.17	typedef double tstamp;
427
428			// return current time as timestampe
429			tstamp now ();
430
431	root	1.25	int similar_direction (int a, int b);
432
433	root	1.1	#endif
434