/***
*strspn.c - find length of initial substring of chars from a control string
*
* Copyright (c) 1985-1997, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines strspn() - finds the length of the initial substring of
* a string consisting entirely of characters from a control string.
*
* defines strcspn()- finds the length of the initial substring of
* a string consisting entirely of characters not in a control string.
*
* defines strpbrk()- finds the index of the first character in a string
* that is not in a control string
*
*******************************************************************************/
/***
*char *strpbrk(string, control) - scans string for a character from control
*
*Purpose:
* Finds the first occurence in string of any character from
* the control string.
*
*Entry:
* char *string - string to search in
* char *control - string containing characters to search for
*
*Exit:
* returns a pointer to the first character from control found
* in string.
* returns NULL if string and control have no characters in common.
*
*Exceptions:
*
*******************************************************************************/
char *strpbrk(const char * string, const char * control)
{
const unsigned char *str = (unsigned char *)string;
const unsigned char *ctrl = (unsigned char *)control;
unsigned char map[32];
int count;
/* Clear out bit map */
for(count=0; count<32; count++)
map[count] = 0;
/* Set bits in control map */
while(*ctrl)
{
map[*ctrl >> 3] |= (1 << (*ctrl & 7));
ctrl++;
}
/* 1st char in control map stops search */
while(*str)
{
if(map[*str >> 3] & (1 << (*str & 7)))
return((char *)str);
str++;
}
return 0;
}