All of the things that confstr() returns are compile-time constants.

It's silly to call sysctl() to get the value of _PATH_STDPATH from
<paths.h> when we can just use it directly.  This greatly simplifies
the implementation.  (This is also part of my grand scheme to get
rid of sysctl's `user' category, which should never have been created.)

Use strlcpy() instead of strncpy() as it has the exact semantics we want.

1 files changed, 10 insertions, 31 deletions

diff --git a/lib/libc/gen/confstr.c b/lib/libc/gen/confstr.c
index 753287dbc8b4..ad2e5a0959c3 100644
--- a/lib/libc/gen/confstr.c
+++ b/lib/libc/gen/confstr.c
@@ -38,48 +38,27 @@ static char sccsid[] = "@(#)confstr.c	8.1 (Berkeley) 6/4/93";
 __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
-#include <sys/sysctl.h>
 
 #include <errno.h>
 #include <paths.h>
-#include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
 
 size_t
-confstr(name, buf, len)
-	int name;
-	char *buf;
-	size_t len;
+confstr(int name, char *buf, size_t len)
 {
-	size_t tlen;
-	int mib[2], sverrno;
-	char *p;
+	const char *p;
 
 	switch (name) {
 	case _CS_PATH:
-		mib[0] = CTL_USER;
-		mib[1] = USER_CS_PATH;
-		if (sysctl(mib, 2, NULL, &tlen, NULL, 0) == -1)
-			return (-1);
-		if (len != 0 && buf != NULL) {
-			if ((p = malloc(tlen)) == NULL)
-				return (-1);
-			if (sysctl(mib, 2, p, &tlen, NULL, 0) == -1) {
-				sverrno = errno;
-				free(p);
-				errno = sverrno;
-				return (-1);
-			}
-			/*
-			 * POSIX 1003.2 requires partial return of
-			 * the string -- that should be *real* useful.
-			 */
-			(void)strncpy(buf, p, len - 1);
-			buf[len - 1] = '\0';
-			free(p);
-		}
-		return (tlen + 1);
+		p = _PATH_STDPATH;
+		goto docopy;
+
+docopy:
+		if (len != 0 && buf != NULL)
+			strlcpy(buf, p, len);
+		return (strlen(p) + 1);
+
 	default:
 		errno = EINVAL;
 		return (0);