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; }

// 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:	1.36
Committed:	Thu Jan 25 03:54:45 2007 UTC (17 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.35:	+6 -0 lines
Log Message:	added checkrusage extension
#	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	1.28	// this is much faster than crossfires original algorithm
51			// on modern cpus
52			inline int
53			isqrt (int n)
54			{
55			return (int)sqrtf ((float)n);
56			}
57
58			// this is only twice as fast as naive sqrtf (dxdy+dydy)
59			#if 0
60			// and has a max. error of 6 in the range -100..+100.
61			#else
62			// and has a max. error of 9 in the range -100..+100.
63			#endif
64			inline int
65			idistance (int dx, int dy)
66			{
67			unsigned int dx_ = abs (dx);
68			unsigned int dy_ = abs (dy);
69
70			#if 0
71			return dx_ > dy_
72			? (dx_ * 61685 + dy_ * 26870) >> 16
73			: (dy_ * 61685 + dx_ * 26870) >> 16;
74			#else
75	root	1.30	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
76	root	1.28	#endif
77			}
78
79	root	1.29	/*
80			* absdir(int): Returns a number between 1 and 8, which represent
81			* the "absolute" direction of a number (it actually takes care of
82			* "overflow" in previous calculations of a direction).
83			*/
84			inline int
85			absdir (int d)
86			{
87			return ((d - 1) & 7) + 1;
88			}
89	root	1.28
90	root	1.1	// makes dynamically allocated objects zero-initialised
91			struct zero_initialised
92			{
93	root	1.11	void operator new (size_t s, void p)
94			{
95			memset (p, 0, s);
96			return p;
97			}
98
99			void *operator new (size_t s)
100			{
101			return g_slice_alloc0 (s);
102			}
103
104			void *operator new[] (size_t s)
105			{
106			return g_slice_alloc0 (s);
107			}
108
109			void operator delete (void *p, size_t s)
110			{
111			g_slice_free1 (s, p);
112			}
113
114			void operator delete[] (void *p, size_t s)
115			{
116			g_slice_free1 (s, p);
117			}
118			};
119
120	root	1.20	void *salloc_ (int n) throw (std::bad_alloc);
121			void salloc_ (int n, void src) throw (std::bad_alloc);
122
123	root	1.12	// strictly the same as g_slice_alloc, but never returns 0
124	root	1.20	template<typename T>
125			inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
126
127	root	1.17	// also copies src into the new area, like "memdup"
128	root	1.18	// if src is 0, clears the memory
129			template<typename T>
130	root	1.20	inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
131	root	1.18
132	root	1.21	// clears the memory
133			template<typename T>
134			inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
135
136	root	1.12	// for symmetry
137	root	1.18	template<typename T>
138	root	1.20	inline void sfree (T *ptr, int n = 1) throw ()
139	root	1.12	{
140	root	1.36	#ifdef PREFER_MALLOC
141			free (ptr);
142			#else
143	root	1.20	g_slice_free1 (n * sizeof (T), (void *)ptr);
144	root	1.36	#endif
145	root	1.12	}
146	root	1.11
147			// a STL-compatible allocator that uses g_slice
148			// boy, this is verbose
149			template<typename Tp>
150			struct slice_allocator
151			{
152			typedef size_t size_type;
153			typedef ptrdiff_t difference_type;
154			typedef Tp *pointer;
155			typedef const Tp *const_pointer;
156			typedef Tp &reference;
157			typedef const Tp &const_reference;
158			typedef Tp value_type;
159
160			template <class U>
161			struct rebind
162			{
163			typedef slice_allocator<U> other;
164			};
165
166			slice_allocator () throw () { }
167			slice_allocator (const slice_allocator &o) throw () { }
168			template<typename Tp2>
169			slice_allocator (const slice_allocator<Tp2> &) throw () { }
170
171			~slice_allocator () { }
172
173			pointer address (reference x) const { return &x; }
174			const_pointer address (const_reference x) const { return &x; }
175
176			pointer allocate (size_type n, const_pointer = 0)
177			{
178	root	1.18	return salloc<Tp> (n);
179	root	1.11	}
180
181			void deallocate (pointer p, size_type n)
182			{
183	root	1.19	sfree<Tp> (p, n);
184	root	1.11	}
185
186			size_type max_size ()const throw ()
187			{
188			return size_t (-1) / sizeof (Tp);
189			}
190
191			void construct (pointer p, const Tp &val)
192			{
193			::new (p) Tp (val);
194			}
195
196			void destroy (pointer p)
197			{
198			p->~Tp ();
199			}
200	root	1.1	};
201
202	root	1.32	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
203			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
204			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
205			struct tausworthe_random_generator
206			{
207	root	1.34	// generator
208	root	1.32	uint32_t state [4];
209
210	root	1.34	void operator =(const tausworthe_random_generator &src)
211			{
212			state [0] = src.state [0];
213			state [1] = src.state [1];
214			state [2] = src.state [2];
215			state [3] = src.state [3];
216			}
217
218			void seed (uint32_t seed);
219	root	1.32	uint32_t next ();
220
221	root	1.34	// uniform distribution
222	root	1.32	uint32_t operator ()(uint32_t r_max)
223			{
224	root	1.34	return is_constant (r_max)
225			? this->next () % r_max
226			: get_range (r_max);
227	root	1.32	}
228
229			// return a number within (min .. max)
230			int operator () (int r_min, int r_max)
231			{
232	root	1.34	return is_constant (r_min) && is_constant (r_max)
233			? r_min + (*this) (max (r_max - r_min + 1, 1))
234			: get_range (r_min, r_max);
235	root	1.32	}
236
237			double operator ()()
238			{
239	root	1.34	return this->next () / (double)0xFFFFFFFFU;
240	root	1.32	}
241	root	1.34
242			protected:
243			uint32_t get_range (uint32_t r_max);
244			int get_range (int r_min, int r_max);
245	root	1.32	};
246
247			typedef tausworthe_random_generator rand_gen;
248
249			extern rand_gen rndm;
250
251	root	1.7	template<class T>
252			struct refptr
253			{
254			T *p;
255
256			refptr () : p(0) { }
257			refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); }
258			refptr (T *p) : p(p) { if (p) p->refcnt_inc (); }
259			~refptr () { if (p) p->refcnt_dec (); }
260
261			const refptr<T> &operator =(T *o)
262			{
263			if (p) p->refcnt_dec ();
264			p = o;
265			if (p) p->refcnt_inc ();
266
267			return *this;
268			}
269
270			const refptr<T> &operator =(const refptr<T> o)
271			{
272			*this = o.p;
273			return *this;
274			}
275
276			T &operator * () const { return *p; }
277			T *operator ->() const { return p; }
278
279			operator T *() const { return p; }
280			};
281
282	root	1.24	typedef refptr<maptile> maptile_ptr;
283	root	1.22	typedef refptr<object> object_ptr;
284			typedef refptr<archetype> arch_ptr;
285	root	1.24	typedef refptr<client> client_ptr;
286			typedef refptr<player> player_ptr;
287	root	1.22
288	root	1.4	struct str_hash
289			{
290			std::size_t operator ()(const char *s) const
291			{
292			unsigned long hash = 0;
293
294			/* use the one-at-a-time hash function, which supposedly is
295			* better than the djb2-like one used by perl5.005, but
296			* certainly is better then the bug used here before.
297			* see http://burtleburtle.net/bob/hash/doobs.html
298			*/
299			while (*s)
300			{
301			hash += *s++;
302			hash += hash << 10;
303			hash ^= hash >> 6;
304			}
305
306			hash += hash << 3;
307			hash ^= hash >> 11;
308			hash += hash << 15;
309
310			return hash;
311			}
312			};
313
314			struct str_equal
315			{
316			bool operator ()(const char a, const char b) const
317			{
318			return !strcmp (a, b);
319			}
320			};
321
322	root	1.26	template<class T>
323			struct unordered_vector : std::vector<T, slice_allocator<T> >
324	root	1.6	{
325	root	1.11	typedef typename unordered_vector::iterator iterator;
326	root	1.6
327			void erase (unsigned int pos)
328			{
329			if (pos < this->size () - 1)
330			(this)[pos] = (this)[this->size () - 1];
331
332			this->pop_back ();
333			}
334
335			void erase (iterator i)
336			{
337			erase ((unsigned int )(i - this->begin ()));
338			}
339			};
340
341	root	1.26	template<class T, int T::* index>
342			struct object_vector : std::vector<T , slice_allocator<T > >
343			{
344			void insert (T *obj)
345			{
346			assert (!(obj->*index));
347			push_back (obj);
348			obj->*index = this->size ();
349			}
350
351			void insert (T &obj)
352			{
353			insert (&obj);
354			}
355
356			void erase (T *obj)
357			{
358			assert (obj->*index);
359			int pos = obj->*index;
360			obj->*index = 0;
361
362			if (pos < this->size ())
363			{
364			(this)[pos - 1] = (this)[this->size () - 1];
365			(this)[pos - 1]->index = pos;
366			}
367
368			this->pop_back ();
369			}
370
371			void erase (T &obj)
372			{
373			errase (&obj);
374			}
375			};
376
377	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
378			void assign (char dst, const char src, int maxlen);
379
380			// type-safe version of assign
381	root	1.9	template<int N>
382			inline void assign (char (&dst)[N], const char *src)
383			{
384	root	1.10	assign ((char *)&dst, src, N);
385	root	1.9	}
386
387	root	1.17	typedef double tstamp;
388
389			// return current time as timestampe
390			tstamp now ();
391
392	root	1.25	int similar_direction (int a, int b);
393
394	root	1.1	#endif
395