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#ifndef SHSTR_H__ |
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#define SHSTR_H__ |
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extern int buf_overflow(const char *buf1, const char *buf2, int bufsize); |
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struct shstr |
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{ |
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const char *s; |
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static int &refcnt (const char *s) |
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{ |
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return *((int *)s - 1); |
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} |
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static int &length (const char *s) |
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{ |
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return *((int *)s - 2); |
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} |
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int &refcnt () const |
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{ |
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return refcnt (s); |
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} |
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|
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int length () const |
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{ |
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return s ? length (s) : 0; |
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} |
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static const char *find (const char *s); |
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static const char *intern (const char *s); |
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static void gc (); // garbage collect a few strings |
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// this is used for informational messages and the like |
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const char *operator &() const { return s ? s : "<nil>"; } |
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const char &operator [](int i) const { return s[i]; } |
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operator const char *() const { return s; } |
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shstr () |
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: s (0) |
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{ |
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} |
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shstr (const shstr &sh) |
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: s (sh.s) |
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{ |
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if (s) ++refcnt (); |
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} |
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explicit shstr (const char *s) |
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: s (intern (s)) |
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{ |
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} |
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~shstr () |
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{ |
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if (s) --refcnt (); |
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} |
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const shstr &operator =(const shstr &sh) |
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{ |
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if (s) --refcnt (); |
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s = sh.s; |
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if (s) ++refcnt (); |
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return *this; |
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} |
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const shstr &operator =(const char *str) |
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{ |
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if (s) --refcnt (); |
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s = intern (str); |
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return *this; |
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} |
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}; |
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inline int strlen (const shstr &sh) |
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{ |
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return sh.length (); |
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} |
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inline bool operator ==(const shstr &a, const shstr &b) |
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{ |
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return a.s == b.s; |
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} |
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inline bool operator !=(const shstr &a, const shstr &b) |
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{ |
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return !(a == b); |
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} |
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#endif |
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