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/***
*strtok.c - tokenize a string with given delimiters
*
* Copyright (c) 1989-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines strtok() - breaks string into series of token
* via repeated calls.
*
*Revision History:
* 06-01-89 JCR C version created.
* 02-27-90 GJF Fixed calling type, #include <cruntime.h>, fixed
* copyright.
* 08-14-90 SBM Removed now redundant #include <stddef.h>
* 10-02-90 GJF New-style function declarator.
* 07-17-91 GJF Multi-thread support for Win32 [_WIN32_].
* 10-26-91 GJF Fixed nasty bug - search for end-of-token could run
* off the end of the string.
* 02-17-93 GJF Changed for new _getptd().
* 05-21-93 GJF Used unsigned char pointers to access control and
* source strings.
*
*******************************************************************************/
#include <cruntime.h>
#include <string.h>
#ifdef MTHREAD
#include <os2dll.h>
#endif
/***
*char *strtok(string, control) - tokenize string with delimiter in control
*
*Purpose:
* strtok 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 char of the
* first token, and will write a null char 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 ascii char. the null char is always a control char.
*
*Entry:
* char *string - string to tokenize, or NULL to get next token
* char *control - 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:
*
*******************************************************************************/
char * _CRTAPI1 strtok (
char * string,
const char * control
)
{
unsigned char *str = string;
const unsigned char *ctrl = control;
unsigned char map[32];
int count;
char *token;
#ifdef MTHREAD
_ptiddata ptd = _getptd();
#else
static char *nextoken;
#endif
/* Clear control map */
for (count = 0; count < 32; count++)
map[count] = 0;
/* Set bits in delimiter table */
do {
map[*ctrl >> 3] |= (1 << (*ctrl & 7));
} while (*ctrl++);
/* If string==NULL, continue with previous string */
if (!str)
#ifdef MTHREAD
str = ptd->_token;
#else
str = nextoken;
#endif
/* 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 ( (map[*str >> 3] & (1 << (*str & 7))) && *str )
str++;
token = str;
/* Find the end of the token. If it is not the end of the string,
* put a null there. */
for ( ; *str ; str++ )
if ( map[*str >> 3] & (1 << (*str & 7)) ) {
*str++ = '\0';
break;
}
/* Update nextoken (or the corresponding field in the per-thread data
* structure */
#ifdef MTHREAD
ptd->_token = str;
#else
nextoken = str;
#endif
/* Determine if a token has been found. */
if ( token == str )
return NULL;
else
return token;
}
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