sysdeps/generic/strspn.c

   1 /* Copyright (C) 1991 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <string.h>
  21
  22
  23 /* Return the length of the maximum initial segment
  24    of S which contains only characters in ACCEPT.  */
  25 size_t
  26 DEFUN(strspn, (s, accept), CONST char *s AND CONST char *accept)
  27 {
  28   register CONST char *p;
  29   register CONST char *a;
  30   register size_t count = 0;
  31
  32   for (p = s; *p != '\0'; ++p)
  33     {
  34       for (a = accept; *a != '\0'; ++a)
  35         if (*p == *a)
  36           break;
  37       if (*a == '\0')
  38         return count;
  39       else
  40         ++count;
  41     }
  42
  43   return count;
  44 }