server/include/util.h

#ifndef UTIL_H__
#define UTIL_H__

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

#include <cstddef>

#include <glib.h>

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

// 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);
  }
};

// strictly the same as g_slice_alloc, but never returns 0
void *alloc (int s) throw (std::bad_alloc);
// for symmetry
inline void dealloc (void *p, int s) throw ()
{
  g_slice_free1 (s, p);
}

// 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 static_cast<pointer>(alloc (n * sizeof (Tp)));
  }

  void deallocate (pointer p, size_type n)
  {
    dealloc (static_cast<void *>(p), n * sizeof (Tp));
  }

  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 ();
  }
};

struct refcounted
{
  mutable int refcnt;
  refcounted () : refcnt (0) { }
  void refcnt_inc () { ++refcnt; }
  void refcnt_dec () { --refcnt; }
};

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; }
};

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);
  }
};

#include <vector>

template<class obj>
struct unordered_vector : std::vector<obj, slice_allocator<obj> >
{
  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<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? a : v >(T)b ? b : v; }

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

// 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);
}

#endif

Revision:	1.15
Committed:	Sat Sep 16 13:11:20 2006 UTC (17 years, 9 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.14:	+1 -2 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#ifndef UTIL_H__
2			#define UTIL_H__
3
4	root	1.2	#if __GNUC__ >= 3
5			# define is_constant(c) __builtin_constant_p (c)
6			#else
7			# define is_constant(c) 0
8			#endif
9
10	root	1.11	#include <cstddef>
11
12			#include <glib.h>
13
14	root	1.14	// use a gcc extension for auto declarations until ISO C++ sanctifies them
15			#define AUTODECL(var,expr) typeof(expr) var = (expr)
16
17	root	1.1	// makes dynamically allocated objects zero-initialised
18			struct zero_initialised
19			{
20	root	1.11	void operator new (size_t s, void p)
21			{
22			memset (p, 0, s);
23			return p;
24			}
25
26			void *operator new (size_t s)
27			{
28			return g_slice_alloc0 (s);
29			}
30
31			void *operator new[] (size_t s)
32			{
33			return g_slice_alloc0 (s);
34			}
35
36			void operator delete (void *p, size_t s)
37			{
38			g_slice_free1 (s, p);
39			}
40
41			void operator delete[] (void *p, size_t s)
42			{
43			g_slice_free1 (s, p);
44			}
45			};
46
47	root	1.12	// strictly the same as g_slice_alloc, but never returns 0
48	root	1.11	void *alloc (int s) throw (std::bad_alloc);
49	root	1.12	// for symmetry
50			inline void dealloc (void *p, int s) throw ()
51			{
52			g_slice_free1 (s, p);
53			}
54	root	1.11
55			// a STL-compatible allocator that uses g_slice
56			// boy, this is verbose
57			template<typename Tp>
58			struct slice_allocator
59			{
60			typedef size_t size_type;
61			typedef ptrdiff_t difference_type;
62			typedef Tp *pointer;
63			typedef const Tp *const_pointer;
64			typedef Tp &reference;
65			typedef const Tp &const_reference;
66			typedef Tp value_type;
67
68			template <class U>
69			struct rebind
70			{
71			typedef slice_allocator<U> other;
72			};
73
74			slice_allocator () throw () { }
75			slice_allocator (const slice_allocator &o) throw () { }
76			template<typename Tp2>
77			slice_allocator (const slice_allocator<Tp2> &) throw () { }
78
79			~slice_allocator () { }
80
81			pointer address (reference x) const { return &x; }
82			const_pointer address (const_reference x) const { return &x; }
83
84			pointer allocate (size_type n, const_pointer = 0)
85			{
86			return static_cast<pointer>(alloc (n * sizeof (Tp)));
87			}
88
89			void deallocate (pointer p, size_type n)
90			{
91	root	1.13	dealloc (static_cast<void >(p), n sizeof (Tp));
92	root	1.11	}
93
94			size_type max_size ()const throw ()
95			{
96			return size_t (-1) / sizeof (Tp);
97			}
98
99			void construct (pointer p, const Tp &val)
100			{
101			::new (p) Tp (val);
102			}
103
104			void destroy (pointer p)
105			{
106			p->~Tp ();
107			}
108	root	1.1	};
109
110	root	1.7	struct refcounted
111			{
112			mutable int refcnt;
113			refcounted () : refcnt (0) { }
114			void refcnt_inc () { ++refcnt; }
115	root	1.15	void refcnt_dec () { --refcnt; }
116	root	1.7	};
117
118			template<class T>
119			struct refptr
120			{
121			T *p;
122
123			refptr () : p(0) { }
124			refptr (const refptr<T> &p) : p(p.p) { if (p) p->refcnt_inc (); }
125			refptr (T *p) : p(p) { if (p) p->refcnt_inc (); }
126			~refptr () { if (p) p->refcnt_dec (); }
127
128			const refptr<T> &operator =(T *o)
129			{
130			if (p) p->refcnt_dec ();
131			p = o;
132			if (p) p->refcnt_inc ();
133
134			return *this;
135			}
136
137			const refptr<T> &operator =(const refptr<T> o)
138			{
139			*this = o.p;
140			return *this;
141			}
142
143			T &operator * () const { return *p; }
144			T *operator ->() const { return p; }
145
146			operator T *() const { return p; }
147			};
148
149	root	1.4	struct str_hash
150			{
151			std::size_t operator ()(const char *s) const
152			{
153			unsigned long hash = 0;
154
155			/* use the one-at-a-time hash function, which supposedly is
156			* better than the djb2-like one used by perl5.005, but
157			* certainly is better then the bug used here before.
158			* see http://burtleburtle.net/bob/hash/doobs.html
159			*/
160			while (*s)
161			{
162			hash += *s++;
163			hash += hash << 10;
164			hash ^= hash >> 6;
165			}
166
167			hash += hash << 3;
168			hash ^= hash >> 11;
169			hash += hash << 15;
170
171			return hash;
172			}
173			};
174
175			struct str_equal
176			{
177			bool operator ()(const char a, const char b) const
178			{
179			return !strcmp (a, b);
180			}
181			};
182
183	root	1.6	#include <vector>
184
185			template<class obj>
186	root	1.11	struct unordered_vector : std::vector<obj, slice_allocator<obj> >
187	root	1.6	{
188	root	1.11	typedef typename unordered_vector::iterator iterator;
189	root	1.6
190			void erase (unsigned int pos)
191			{
192			if (pos < this->size () - 1)
193			(this)[pos] = (this)[this->size () - 1];
194
195			this->pop_back ();
196			}
197
198			void erase (iterator i)
199			{
200			erase ((unsigned int )(i - this->begin ()));
201			}
202			};
203
204	root	1.8	template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
205			template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
206			template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? a : v >(T)b ? b : v; }
207
208			template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
209
210	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
211			void assign (char dst, const char src, int maxlen);
212
213			// type-safe version of assign
214	root	1.9	template<int N>
215			inline void assign (char (&dst)[N], const char *src)
216			{
217	root	1.10	assign ((char *)&dst, src, N);
218	root	1.9	}
219
220	root	1.1	#endif
221