/*** *wcstok.c - tokenize a wide-character string with given delimiters * * Copyright (c) 1989-1997, Microsoft Corporation. All rights reserved. * *Purpose: * defines wcstok() - breaks wide-character string into series of token * via repeated calls. * *******************************************************************************/ #include #include #ifdef _MT #include #endif /* _MT */ /*** *wchar_t *wcstok(string, control) - tokenize string with delimiter in control * (wide-characters) * *Purpose: * wcstok considers the string to consist of a sequence of zero or more * text tokens separated by spans of one or more control chars. the first * call, with string specified, returns a pointer to the first wchar_t of * the first token, and will write a null wchar_t into string immediately * following the returned token. subsequent calls with zero for the first * argument (string) will work thru the string until no tokens remain. the * control string may be different from call to call. when no tokens remain * in string a NULL pointer is returned. remember the control chars with a * bit map, one bit per wchar_t. the null wchar_t is always a control char * (wide-characters). * *Entry: * wchar_t *string - wchar_t string to tokenize, or NULL to get next token * wchar_t *control - wchar_t string of characters to use as delimiters * *Exit: * returns pointer to first token in string, or if string * was NULL, to next token * returns NULL when no more tokens remain. * *Uses: * *Exceptions: * *******************************************************************************/ wchar_t * __cdecl wcstok ( wchar_t * string, const wchar_t * control ) { wchar_t *token; const wchar_t *ctl; #ifdef _MT _ptiddata ptd = _getptd(); #else /* _MT */ static wchar_t *nextoken; #endif /* _MT */ /* If string==NULL, continue with previous string */ if (!string) #ifdef _MT string = ptd->_wtoken; #else /* _MT */ string = nextoken; #endif /* _MT */ /* Find beginning of token (skip over leading delimiters). Note that * there is no token iff this loop sets string to point to the terminal * null (*string == '\0') */ while (*string) { for (ctl=control; *ctl && *ctl != *string; ctl++) ; if (!*ctl) break; string++; } token = string; /* Find the end of the token. If it is not the end of the string, * put a null there. */ for ( ; *string ; string++ ) { for (ctl=control; *ctl && *ctl != *string; ctl++) ; if (*ctl) { *string++ = '\0'; break; } } /* Update nextoken (or the corresponding field in the per-thread data * structure */ #ifdef _MT ptd->_wtoken = string; #else /* _MT */ nextoken = string; #endif /* _MT */ /* Determine if a token has been found. */ if ( token == string ) return NULL; else return token; }