| 1 | #ifndef SHSTR_H__ |
1 | #ifndef SHSTR_H__ |
| 2 | #define SHSTR_H__ |
2 | #define SHSTR_H__ |
| 3 | |
3 | |
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4 | #include "util.h" |
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5 | |
| 4 | extern int buf_overflow(const char *buf1, const char *buf2, int bufsize); |
6 | extern int buf_overflow (const char *buf1, const char *buf2, int bufsize); |
| 5 | |
7 | |
| 6 | struct shstr |
8 | struct shstr |
| 7 | { |
9 | { |
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10 | static const char *null; |
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11 | |
| 8 | const char *s; |
12 | const char *s; |
| 9 | |
13 | |
| 10 | static int &refcnt (const char *s) |
14 | static int &refcnt (const char *s) |
| 11 | { |
15 | { |
| 12 | return *((int *)s - 1); |
16 | return *((int *)s - 1); |
| … | |
… | |
| 22 | return refcnt (s); |
26 | return refcnt (s); |
| 23 | } |
27 | } |
| 24 | |
28 | |
| 25 | int length () const |
29 | int length () const |
| 26 | { |
30 | { |
| 27 | return s ? length (s) : 0; |
31 | return length (s); |
| 28 | } |
32 | } |
| 29 | |
33 | |
| 30 | static const char *find (const char *s); |
34 | static const char *find (const char *s); |
| 31 | static const char *intern (const char *s); |
35 | static const char *intern (const char *s); |
| 32 | |
36 | |
| 33 | static void gc (); // garbage collect a few strings |
37 | static void gc (); // garbage collect a few strings |
| 34 | |
38 | |
| 35 | // this is used for informational messages and the like |
39 | // this is used for informational messages and the like |
| 36 | const char *operator &() const { return s ? s : "<nil>"; } |
40 | const char *operator &() const { return s; } |
| 37 | |
41 | |
| 38 | const char &operator [](int i) const { return s[i]; } |
42 | const char &operator [](int i) const { return s[i]; } |
| 39 | operator const char *() const { return s; } |
43 | operator const char *() const { return s == null ? 0 : s; } |
| 40 | |
44 | |
| 41 | shstr () |
45 | shstr () |
| 42 | : s (0) |
46 | : s (null) |
| 43 | { |
47 | { |
| 44 | } |
48 | } |
| 45 | |
49 | |
| 46 | shstr (const shstr &sh) |
50 | shstr (const shstr &sh) |
| 47 | : s (sh.s) |
51 | : s (sh.s) |
| 48 | { |
52 | { |
| 49 | if (s) ++refcnt (); |
53 | ++refcnt (); |
| 50 | } |
54 | } |
| 51 | |
55 | |
| 52 | explicit shstr (const char *s) |
56 | explicit shstr (const char *s) |
| 53 | : s (intern (s)) |
57 | : s (intern (s)) |
| 54 | { |
58 | { |
| 55 | } |
59 | } |
| 56 | |
60 | |
| 57 | ~shstr () |
61 | ~shstr () |
| 58 | { |
62 | { |
| 59 | if (s) --refcnt (); |
63 | --refcnt (); |
| 60 | } |
64 | } |
| 61 | |
65 | |
| 62 | const shstr &operator =(const shstr &sh) |
66 | const shstr &operator =(const shstr &sh) |
| 63 | { |
67 | { |
| 64 | if (s) --refcnt (); |
68 | --refcnt (); |
| 65 | s = sh.s; |
69 | s = sh.s; |
| 66 | if (s) ++refcnt (); |
70 | ++refcnt (); |
| 67 | |
71 | |
| 68 | return *this; |
72 | return *this; |
| 69 | } |
73 | } |
| 70 | |
74 | |
| 71 | const shstr &operator =(const char *str) |
75 | const shstr &operator =(const char *str) |
| 72 | { |
76 | { |
| 73 | if (s) --refcnt (); |
77 | --refcnt (); |
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78 | |
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79 | #if 0 |
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80 | // this optimises the important case of str == constant 0 |
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81 | if (is_constant (str)) |
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82 | s = str ? intern (str) : null; |
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83 | else |
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84 | #endif |
| 74 | s = intern (str); |
85 | s = intern (str); |
| 75 | |
86 | |
| 76 | return *this; |
87 | return *this; |
| 77 | } |
88 | } |
| 78 | }; |
89 | }; |
| 79 | |
90 | |
