/*** *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; }