server/include/shstr.h

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008,2009 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 Affero 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 Affero GNU General Public License
 * and 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 SHSTR_H__
#define SHSTR_H__

#include <cstring>
#include <sstream>

#include "traits.h"

extern size_t shstr_alloc;

extern int buf_overflow (const char *buf1, const char *buf2, int bufsize);

template<int size>
struct shstr_vec
{
  uint32_t len;
  uint32_t refcnt;
  char string[size];
};

// this class is a non-refcounted shared string
// it cannot be used to create or store shared strings, but
// it can be used to apss shared strings around, i.e. as function arguments
// or return values. their lifetime must not span a gc () call, i.e.
// they are only valid as temporary values within the same server tick.
struct shstr_tmp
{
  static shstr_vec<sizeof ("(null)")> nullvec;
  static const char *null () { return nullvec.string; } // this is the null pointer value

  const char *s;

  static unsigned int &length (const char *s)
  {
    return *((unsigned int *)s - 2);
  }

  int length () const
  {
    return length (s);
  }

  // returns whether this shared string begins with the given prefix,
  // used mainly for searches when users give only the start of a name.
  bool starts_with (const char *prefix) const
  {
    int plen = strlen (prefix);

    return length () >= plen && !strncasecmp (s, prefix, plen);
  }

  // returns true if the substring is contained in the shstr
  // if the shstr is 0, then this always returns false.
  // the shstr is (theoretically) treated as a comma/colon/space etc. separated list.
  bool contains (const char *substring) const
  {
    return s != null () && strstr (s, substring);
  }

  //TODO: case sensitive should be eradicated
  bool eq_nc (const char *otherstring) const
  {
    return !strcasecmp (s, otherstring);
  }

  shstr_tmp ()
  : s (null ())
  {
  }

  shstr_tmp (const shstr_tmp &sh)
  : s (sh.s)
  {
  }

  shstr_tmp operator =(const shstr_tmp &sh)
  {
    s = sh.s;

    return *this;
  }

  // this is used for informational messages and the like
  const char *operator &() const { return s; }

  operator const char *() const { return s == null () ? 0 : s; }

protected:
  // dummy is there so it isn't used as type converter accidentally
  shstr_tmp (int dummy, const char *s)
  : s(s)
  {
  }
};

inline bool operator ==(const shstr_tmp &a, const shstr_tmp &b)
{
  return a.s == b.s;
}

inline bool operator !=(const shstr_tmp &a, const shstr_tmp &b)
{
  return a.s != b.s;
}

inline int strlen (shstr_tmp sh)
{
  return sh.length ();
}

static inline std::ostream &operator <<(std::ostream &o, shstr_tmp sh)
{
  o.write (sh.s, sh.length ());

  return o;
}

struct shstr : shstr_tmp
{
  static unsigned int &refcnt (const char *s)
  {
    return *((unsigned int *)s - 1);
  }

  unsigned int &refcnt () const
  {
    return refcnt (s);
  }

  shstr ()
  {
  }

  static const char *find (const char *s);
  static const char *intern (const char *s);

  static void gc (); // garbage collect a few strings

  shstr (const shstr &sh)
  : shstr_tmp (sh)
  {
    ++refcnt ();
  }

  shstr (const shstr_tmp &sh)
  : shstr_tmp (sh)
  {
    ++refcnt ();
  }

  explicit shstr (const char *str)
  : shstr_tmp (0, is_constant (str) && !str ? null () : intern (str))
  {
  }

  ~shstr ()
  {
    --refcnt ();
  }

  using shstr_tmp::operator &;
  using shstr_tmp::operator const char *;

  // (note: not the copy constructor)
  shstr &operator =(const shstr_tmp &sh)
  {
    --refcnt ();
    s = sh.s;
    ++refcnt ();

    return *this;
  }

  // here it comes
  shstr &operator =(const shstr &sh)
  {
    return (*this) = (shstr_tmp)sh;
  }

  // shstr_tmp doesn't have this one
  shstr &operator =(const char *str)
  {
    --refcnt ();
    s = is_constant (str) && !str ? null () : intern (str);

    return *this;
  }
};

// only good for mass comparisons to shstr objects, or very
// temporary passing, basically a non-refcounted shstr
struct shstr_cmp
{
  const char *s;

  // initialies to the non-matching string (as opposed to the null string)
  shstr_cmp ()
  {
    s = 0;
  }

  shstr_cmp (const char *str)
  : s (shstr::find (str))
  {
  }

  shstr_cmp (shstr_tmp sh)
  : s (sh.s)
  {
  }

  // this is used for informational messages and the like
  const char *operator &() const { return s; }

  operator const char *() const { return s; }
};

inline bool operator ==(const shstr_cmp &a, const shstr_tmp &b)
{
  return a.s == b.s;
}

inline bool operator ==(const shstr_tmp &a, const shstr_cmp &b)
{
  return a.s == b.s;
}

#define def2(id,str) extern const shstr id;
#define def(id)      def2(shstr_ ## id, # id)
# include "shstrinc.h"
#undef def
#undef def2

// undefined external reference to catch people using str* functions when they shouldn't
//template<class any> void strcmp (const shstr_tmp &a, any b);
template<class any> void strstr (const shstr_tmp &a, any b);

#endif

Revision:	1.35
Committed:	Fri Nov 6 13:45:28 2009 UTC (14 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_90
Changes since 1.34:	+1 -1 lines
Log Message:	remove or document dead code
#	Content
1	/*
2	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	*
4	* Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	*
6	* Deliantra is free software: you can redistribute it and/or modify it under
7	* the terms of the Affero GNU General Public License as published by the
8	* Free Software Foundation, either version 3 of the License, or (at your
9	* option) any later version.
10	*
11	* 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	*
16	* You should have received a copy of the Affero GNU General Public License
17	* and the GNU General Public License along with this program. If not, see
18	* <http://www.gnu.org/licenses/>.
19	*
20	* The authors can be reached via e-mail to <support@deliantra.net>
21	*/
22
23	#ifndef SHSTR_H__
24	#define SHSTR_H__
25
26	#include <cstring>
27	#include <sstream>
28
29	#include "traits.h"
30
31	extern size_t shstr_alloc;
32
33	extern int buf_overflow (const char buf1, const char buf2, int bufsize);
34
35	template<int size>
36	struct shstr_vec
37	{
38	uint32_t len;
39	uint32_t refcnt;
40	char string[size];
41	};
42
43	// this class is a non-refcounted shared string
44	// it cannot be used to create or store shared strings, but
45	// it can be used to apss shared strings around, i.e. as function arguments
46	// or return values. their lifetime must not span a gc () call, i.e.
47	// they are only valid as temporary values within the same server tick.
48	struct shstr_tmp
49	{
50	static shstr_vec<sizeof ("(null)")> nullvec;
51	static const char *null () { return nullvec.string; } // this is the null pointer value
52
53	const char *s;
54
55	static unsigned int &length (const char *s)
56	{
57	return ((unsigned int )s - 2);
58	}
59
60	int length () const
61	{
62	return length (s);
63	}
64
65	// returns whether this shared string begins with the given prefix,
66	// used mainly for searches when users give only the start of a name.
67	bool starts_with (const char *prefix) const
68	{
69	int plen = strlen (prefix);
70
71	return length () >= plen && !strncasecmp (s, prefix, plen);
72	}
73
74	// returns true if the substring is contained in the shstr
75	// if the shstr is 0, then this always returns false.
76	// the shstr is (theoretically) treated as a comma/colon/space etc. separated list.
77	bool contains (const char *substring) const
78	{
79	return s != null () && strstr (s, substring);
80	}
81
82	//TODO: case sensitive should be eradicated
83	bool eq_nc (const char *otherstring) const
84	{
85	return !strcasecmp (s, otherstring);
86	}
87
88	shstr_tmp ()
89	: s (null ())
90	{
91	}
92
93	shstr_tmp (const shstr_tmp &sh)
94	: s (sh.s)
95	{
96	}
97
98	shstr_tmp operator =(const shstr_tmp &sh)
99	{
100	s = sh.s;
101
102	return *this;
103	}
104
105	// this is used for informational messages and the like
106	const char *operator &() const { return s; }
107
108	operator const char *() const { return s == null () ? 0 : s; }
109
110	protected:
111	// dummy is there so it isn't used as type converter accidentally
112	shstr_tmp (int dummy, const char *s)
113	: s(s)
114	{
115	}
116	};
117
118	inline bool operator ==(const shstr_tmp &a, const shstr_tmp &b)
119	{
120	return a.s == b.s;
121	}
122
123	inline bool operator !=(const shstr_tmp &a, const shstr_tmp &b)
124	{
125	return a.s != b.s;
126	}
127
128	inline int strlen (shstr_tmp sh)
129	{
130	return sh.length ();
131	}
132
133	static inline std::ostream &operator <<(std::ostream &o, shstr_tmp sh)
134	{
135	o.write (sh.s, sh.length ());
136
137	return o;
138	}
139
140	struct shstr : shstr_tmp
141	{
142	static unsigned int &refcnt (const char *s)
143	{
144	return ((unsigned int )s - 1);
145	}
146
147	unsigned int &refcnt () const
148	{
149	return refcnt (s);
150	}
151
152	shstr ()
153	{
154	}
155
156	static const char find (const char s);
157	static const char intern (const char s);
158
159	static void gc (); // garbage collect a few strings
160
161	shstr (const shstr &sh)
162	: shstr_tmp (sh)
163	{
164	++refcnt ();
165	}
166
167	shstr (const shstr_tmp &sh)
168	: shstr_tmp (sh)
169	{
170	++refcnt ();
171	}
172
173	explicit shstr (const char *str)
174	: shstr_tmp (0, is_constant (str) && !str ? null () : intern (str))
175	{
176	}
177
178	~shstr ()
179	{
180	--refcnt ();
181	}
182
183	using shstr_tmp::operator &;
184	using shstr_tmp::operator const char *;
185
186	// (note: not the copy constructor)
187	shstr &operator =(const shstr_tmp &sh)
188	{
189	--refcnt ();
190	s = sh.s;
191	++refcnt ();
192
193	return *this;
194	}
195
196	// here it comes
197	shstr &operator =(const shstr &sh)
198	{
199	return (*this) = (shstr_tmp)sh;
200	}
201
202	// shstr_tmp doesn't have this one
203	shstr &operator =(const char *str)
204	{
205	--refcnt ();
206	s = is_constant (str) && !str ? null () : intern (str);
207
208	return *this;
209	}
210	};
211
212	// only good for mass comparisons to shstr objects, or very
213	// temporary passing, basically a non-refcounted shstr
214	struct shstr_cmp
215	{
216	const char *s;
217
218	// initialies to the non-matching string (as opposed to the null string)
219	shstr_cmp ()
220	{
221	s = 0;
222	}
223
224	shstr_cmp (const char *str)
225	: s (shstr::find (str))
226	{
227	}
228
229	shstr_cmp (shstr_tmp sh)
230	: s (sh.s)
231	{
232	}
233
234	// this is used for informational messages and the like
235	const char *operator &() const { return s; }
236
237	operator const char *() const { return s; }
238	};
239
240	inline bool operator ==(const shstr_cmp &a, const shstr_tmp &b)
241	{
242	return a.s == b.s;
243	}
244
245	inline bool operator ==(const shstr_tmp &a, const shstr_cmp &b)
246	{
247	return a.s == b.s;
248	}
249
250	#define def2(id,str) extern const shstr id;
251	#define def(id) def2(shstr_ ## id, # id)
252	# include "shstrinc.h"
253	#undef def
254	#undef def2
255
256	// undefined external reference to catch people using str* functions when they shouldn't
257	//template<class any> void strcmp (const shstr_tmp &a, any b);
258	template<class any> void strstr (const shstr_tmp &a, any b);
259
260	#endif
261