old-cross-binutils/libiberty/strstr.c

42 lines
1 KiB
C
Raw Normal View History

1999-05-03 07:29:11 +00:00
/* Simple implementation of strstr for systems without it.
This function is in the public domain. */
/*
2001-09-26 18:45:50 +00:00
@deftypefn Supplemental char* strstr (const char *@var{string}, const char *@var{sub})
1999-05-03 07:29:11 +00:00
2001-09-26 18:45:50 +00:00
This function searches for the substring @var{sub} in the string
2001-09-27 20:27:58 +00:00
@var{string}, not including the terminating null characters. A pointer
2001-10-07 22:42:23 +00:00
to the first occurrence of @var{sub} is returned, or @code{NULL} if the
2001-09-26 18:45:50 +00:00
substring is absent. If @var{sub} points to a string with zero
length, the function returns @var{string}.
1999-05-03 07:29:11 +00:00
2001-09-26 18:45:50 +00:00
@end deftypefn
1999-05-03 07:29:11 +00:00
*/
/* FIXME: The above description is ANSI compiliant. This routine has not
been validated to comply with it. -fnf */
2005-04-02 20:20:01 +00:00
#include <stddef.h>
extern char *strchr (const char *, int);
extern int strncmp (const void *, const void *, size_t);
extern size_t strlen (const char *);
1999-05-03 07:29:11 +00:00
char *
2005-04-02 20:20:01 +00:00
strstr (const char *s1, const char *s2)
1999-05-03 07:29:11 +00:00
{
2005-04-02 20:20:01 +00:00
const char *p = s1;
const size_t len = strlen (s2);
1999-05-03 07:29:11 +00:00
for (; (p = strchr (p, *s2)) != 0; p++)
{
if (strncmp (p, s2, len) == 0)
2005-04-02 20:20:01 +00:00
return (char *)p;
1999-05-03 07:29:11 +00:00
}
return (0);
}