1 /* ========================================================================

2 * Copyright 1988-2006 University of Washington

3 *

4 * Licensed under the Apache License, Version 2.0 (the "License");

5 * you may not use this file except in compliance with the License.

6 * You may obtain a copy of the License at

7 *

8 * http://www.apache.org/licenses/LICENSE-2.0

9 *

10 *

11 * ========================================================================

12 */

13

14 /*

15 * Program: Substring search

16 *

17 * Author: Mark Crispin

18 * Networks and Distributed Computing

19 * Computing & Communications

20 * University of Washington

21 * Administration Building, AG-44

22 * Seattle, WA 98195

23 *

24 * Date: 11 May 1989

25 * Last Edited: 30 August 2006

26 */

27 

28 /* Return pointer to first occurance in string of a substring

29 * Accepts: source pointer

30 * substring pointer

31 * Returns: pointer to substring in source or NIL if not found

32 */

33

34 char *strstr (char *cs,char *ct)

35 {

36 char *s;

37 char *t;

38 while (cs = strchr (cs,*ct)) {/* for each occurance of the first character */

39 /* see if remainder of string matches */

40 for (s = cs + 1, t = ct + 1; *t && *s == *t; s++, t++);

41 if (!*t) return cs; /* if ran out of substring then have match */

42 cs++; /* try from next character */

43 }

44 return NIL; /* not found */

45 }