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Comparing deliantra/server/include/shstr.h (file contents):
Revision 1.6 by root, Sun Sep 3 07:57:56 2006 UTC vs.
Revision 1.25 by root, Wed Dec 31 18:07:41 2008 UTC

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

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