diff options
Diffstat (limited to 'lib/strstr.c')
-rw-r--r-- | lib/strstr.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/lib/strstr.c b/lib/strstr.c new file mode 100644 index 00000000..16b748b6 --- /dev/null +++ b/lib/strstr.c @@ -0,0 +1,44 @@ +/* strstr.c -- return the offset of one string within another + Copyright (C) 1989, 1990 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + +/* Written by Mike Rendell <michael@cs.mun.ca>. */ + +/* Return the starting address of string S2 in S1; + return 0 if it is not found. */ + +char * +strstr (s1, s2) + char *s1; + char *s2; +{ + int i; + char *p1; + char *p2; + char *s = s1; + + for (p2 = s2, i = 0; *s; p2 = s2, i++, s++) + { + for (p1 = s; *p1 && *p2 && *p1 == *p2; p1++, p2++) + ; + if (!*p2) + break; + } + if (!*p2) + return s1 + i; + + return 0; +} |