ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/deliantra/server/include/shstr.h
(Generate patch)

Comparing deliantra/server/include/shstr.h (file contents):
Revision 1.23 by root, Sun Dec 28 06:59:27 2008 UTC vs.
Revision 1.31 by root, Thu Jan 1 19:42:43 2009 UTC

… …
20 */ 20 */
21 21
22#ifndef SHSTR_H__ 22#ifndef SHSTR_H__
23#define SHSTR_H__ 23#define SHSTR_H__
24 24
25#include <cstring>
25#include <sstream> 26#include <sstream>
26 27
27#include "util.h" 28#include "traits.h"
28 29
29extern size_t shstr_alloc; 30extern size_t shstr_alloc;
30 31
31extern int buf_overflow (const char *buf1, const char *buf2, int bufsize); 32extern int buf_overflow (const char *buf1, const char *buf2, int bufsize);
32 33
34template<int size>
33struct shstr 35struct shstr_vec
34{ 36{
35 static const char *null; 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
36 51
37 const char *s; 52 const char *s;
38 53
39 static int &refcnt (const char *s)
40 {
41 return *((int *)s - 1);
42 }
43
44 static int &length (const char *s) 54 static unsigned int &length (const char *s)
45 { 55 {
46 return *((int *)s - 2); 56 return *((unsigned int *)s - 2);
47 } 57 }
48 58
49 int &refcnt () const 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 s != null () && strstr (s, substring);
76 }
77
78 //TODO: case sensitive should be eradicated
79 bool eq_nc (const char *otherstring) const
80 {
81 return !strcasecmp (s, otherstring);
82 }
83
84 shstr_tmp ()
85 : s (null ())
86 {
87 }
88
89 shstr_tmp (const shstr_tmp &sh)
90 : s (sh.s)
91 {
92 }
93
94 shstr_tmp operator =(const shstr_tmp &sh)
95 {
96 s = sh.s;
97
98 return *this;
99 }
100
101 // this is used for informational messages and the like
102 const char *operator &() const { return s; }
103
104 operator const char *() const { return s == null () ? 0 : s; }
105
106protected:
107 // dummy is there so it isn't used as type converter accidentally
108 shstr_tmp (int dummy, const char *s)
109 : s(s)
110 {
111 }
112};
113
114inline bool operator ==(const shstr_tmp &a, const shstr_tmp &b)
115{
116 return a.s == b.s;
117}
118
119inline bool operator !=(const shstr_tmp &a, const shstr_tmp &b)
120{
121 return a.s != b.s;
122}
123
124inline int strlen (shstr_tmp sh)
125{
126 return sh.length ();
127}
128
129static std::ostream &operator <<(std::ostream &o, shstr_tmp sh)
130{
131 o.write (sh.s, sh.length ());
132
133 return o;
134}
135
136struct shstr : shstr_tmp
137{
138 static unsigned int &refcnt (const char *s)
139 {
140 return *((unsigned int *)s - 1);
141 }
142
143 unsigned int &refcnt () const
50 { 144 {
51 return refcnt (s); 145 return refcnt (s);
52 } 146 }
53 147
54 int length () const 148 shstr ()
55 { 149 {
56 return length (s);
57 }
58
59 // returns wether this shared string begins with the given prefix,
60 // used mainly for searched when users give only the start of a name.
61 bool begins_with (const char *prefix) const
62 {
63 int plen = strlen (prefix);
64 return !strncasecmp (s, prefix, plen) && length () >= plen;
65 } 150 }
66 151
67 static const char *find (const char *s); 152 static const char *find (const char *s);
68 static const char *intern (const char *s); 153 static const char *intern (const char *s);
69 154
70 static void gc (); // garbage collect a few strings 155 static void gc (); // garbage collect a few strings
71 156
72 // this is used for informational messages and the like
73 const char *operator &() const { return s; }
74
75 const char &operator [](int i) const { return s[i]; }
76 operator const char *() const { return s == null ? 0 : s; }
77
78 shstr ()
79 : s (null)
80 {
81 }
82
83 shstr (const shstr &sh) 157 shstr (const shstr &sh)
84 : s (sh.s) 158 : shstr_tmp (sh)
85 { 159 {
86 ++refcnt (); 160 ++refcnt ();
87 } 161 }
88 162
163 shstr (const shstr_tmp &sh)
164 : shstr_tmp (sh)
165 {
166 ++refcnt ();
167 }
168
89 explicit shstr (const char *s) 169 explicit shstr (const char *str)
90 : s (intern (s)) 170 : shstr_tmp (0, is_constant (str) && !str ? null () : intern (str))
91 { 171 {
92 } 172 }
93 173
94 ~shstr () 174 ~shstr ()
95 { 175 {
96 --refcnt (); 176 --refcnt ();
97 } 177 }
98 178
179 using shstr_tmp::operator &;
180 using shstr_tmp::operator const char *;
181
182 // (note: not the copy constructor)
99 const shstr &operator =(const shstr &sh) 183 shstr &operator =(const shstr_tmp &sh)
100 { 184 {
101 --refcnt (); 185 --refcnt ();
102 s = sh.s; 186 s = sh.s;
103 ++refcnt (); 187 ++refcnt ();
104 188
105 return *this; 189 return *this;
106 } 190 }
107 191
192 // here it comes
193 shstr &operator =(const shstr &sh)
194 {
195 return (*this) = (shstr_tmp)sh;
196 }
197
198 // shstr_tmp doesn't have this one
108 const shstr &operator =(const char *str) 199 shstr &operator =(const char *str)
109 { 200 {
110 --refcnt (); 201 --refcnt ();
111 202 s = is_constant (str) && !str ? null () : intern (str);
112 // this optimises the important case of str == constant 0
113 if (is_constant (str))
114 s = str ? intern (str) : null;
115 else
116 s = intern (str);
117 203
118 return *this; 204 return *this;
119 } 205 }
120
121 bool operator !=(const shstr &b)
122 {
123 return !(*this == b);
124 }
125}; 206};
126 207
127inline bool operator ==(const shstr &a, const shstr &b)
128{
129 return a.s == b.s;
130}
131
132inline int strlen (const shstr &sh)
133{
134 return sh.length ();
135}
136
137inline int strcmp (const shstr &a, const shstr &b)
138{
139 // TODO: use this to find all the occurences of people using strcmp
140 // all uses should be bogus, as we should be never interested in
141 // comparing shstr's alphabetically
142#if 0
143 extern void do_not_use_strcmp_to_compare_shstr_values ();
144 do_not_use_strcmp_to_compare_shstr_values ();
145#endif
146 return a != b;
147}
148
149static std::ostream &operator <<(std::ostream &o, const shstr &sh)
150{
151 o.write (sh.s, sh.length ());
152 return o;
153}
154
155// only good for mass comparisons to shstr objects 208// only good for mass comparisons to shstr objects, or very
209// temporary passing, basically a non-refcounted shstr
156struct shstr_cmp 210struct shstr_cmp
157{ 211{
158 const char *s; 212 const char *s;
159 213
214 // initialies to the non-matching string (as opposed to the null string)
215 shstr_cmp ()
216 {
217 s = 0;
218 }
219
160 explicit shstr_cmp (const char *s) 220 shstr_cmp (const char *str)
161 : s (shstr::find (s)) 221 : s (shstr::find (str))
162 { 222 {
163 } 223 }
164 224
165 shstr_cmp (const shstr_cmp &sh) 225 shstr_cmp (shstr_tmp sh)
166 : s (sh.s)
167 {
168 }
169
170 shstr_cmp (const shstr &sh)
171 : s (sh.s) 226 : s (sh.s)
172 { 227 {
173 } 228 }
174 229
175 // this is used for informational messages and the like 230 // this is used for informational messages and the like
176 const char *operator &() const { return s; } 231 const char *operator &() const { return s; }
177 232
178 shstr_cmp &operator =(const shstr_cmp sh) { s = sh.s; return *this; }
179 operator const char *() const { return s; } 233 operator const char *() const { return s; }
180}; 234};
181 235
182inline bool operator ==(const shstr_cmp &a, const shstr &b) 236inline bool operator ==(const shstr_cmp &a, const shstr_tmp &b)
183{ 237{
184 return a.s == b.s; 238 return a.s == b.s;
185} 239}
186 240
187inline bool operator ==(const shstr &a, const shstr_cmp &b) 241inline bool operator ==(const shstr_tmp &a, const shstr_cmp &b)
188{ 242{
189 return b == a; 243 return a.s == b.s;
190} 244}
191 245
192extern const shstr shstr_null;
193
194#define def(str) extern const shstr shstr_ ## str; 246#define def2(id,str) extern const shstr id;
247#define def(id) def2(shstr_ ## id, # id)
195# include "shstrinc.h" 248# include "shstrinc.h"
196#undef def 249#undef def
250#undef def2
251
252// undefined external reference to catch people using str* functions when they shouldn't
253//template<class any> void strcmp (const shstr_tmp &a, any b);
254template<class any> void strstr (const shstr_tmp &a, any b);
197 255
198#endif 256#endif
199 257

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines