| /* Simple implementation of strstr for systems without it. |
| This function is in the public domain. */ |
| |
| /* |
| |
| @deftypefn Supplemental char* strstr (const char *@var{string}, const char *@var{sub}) |
| |
| This function searches for the substring @var{sub} in the string |
| @var{string}, not including the terminating null characters. A pointer |
| to the first occurrence of @var{sub} is returned, or @code{NULL} if the |
| substring is absent. If @var{sub} points to a string with zero |
| length, the function returns @var{string}. |
| |
| @end deftypefn |
| |
| |
| */ |
| |
| |
| /* FIXME: The above description is ANSI compiliant. This routine has not |
| been validated to comply with it. -fnf */ |
| |
| #include <stddef.h> |
| |
| extern char *strchr (const char *, int); |
| extern int strncmp (const void *, const void *, size_t); |
| extern size_t strlen (const char *); |
| |
| char * |
| strstr (const char *s1, const char *s2) |
| { |
| const char *p = s1; |
| const size_t len = strlen (s2); |
| |
| for (; (p = strchr (p, *s2)) != 0; p++) |
| { |
| if (strncmp (p, s2, len) == 0) |
| return (char *)p; |
| } |
| return (0); |
| } |