52 lines
959 B
C
52 lines
959 B
C
|
/* Simple implementation of strstr for systems without it.
|
||
|
|
This function is in the public domain. */
|
||
|
|
|
||
|
|
/*
|
||
|
|
|
||
|
|
NAME
|
||
|
|
|
||
|
|
strstr -- locate first occurance of a substring
|
||
|
|
|
||
|
|
SYNOPSIS
|
||
|
|
|
||
|
|
#include <string.h>
|
||
|
|
|
||
|
|
char *strstr (char *s1, char *s2)
|
||
|
|
|
||
|
|
DESCRIPTION
|
||
|
|
|
||
|
|
Locates the first occurance in the string pointed to by S1 of
|
||
|
|
the string pointed to by S2. Returns a pointer to the substring
|
||
|
|
found, or a NULL pointer if not found. If S2 points to a string
|
||
|
|
with zero length, the function returns S1.
|
||
|
|
|
||
|
|
BUGS
|
||
|
|
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
/* FIXME: The above description is ANSI compiliant. This routine has not
|
||
|
|
been validated to comply with it. -fnf */
|
||
|
|
|
||
|
|
char *
|
||
|
|
strstr (s1, s2)
|
||
|
|
char *s1, *s2;
|
||
|
|
{
|
||
|
|
register char *p = s1;
|
||
|
|
extern char *strchr ();
|
||
|
|
extern int strncmp ();
|
||
|
|
#if __GNUC__==2
|
||
|
|
extern __SIZE_TYPE__ strlen ();
|
||
|
|
#endif
|
||
|
|
register int len = strlen (s2);
|
||
|
|
|
||
|
|
for (; (p = strchr (p, *s2)) != 0; p++)
|
||
|
|
{
|
||
|
|
if (strncmp (p, s2, len) == 0)
|
||
|
|
{
|
||
|
|
return (p);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return (0);
|
||
|
|
}
|