Fix some issues raised (albeit indirectly) by Isaac Dunham.

POLL_IN defined as a constant by some libc.
Factor out login.c's change_identity() to xwrap.c as xsetuser().
Replace xsetuid() with xsetuser()
Put a space between argument globals and non-argument globals.
TT starts zeroed, don't need to re-zero entries in it.
STDIN_FILENO has been 0 since 1969, even DOS copied that. Just say 0.
Added an xchroot() using xchdir() to lib/xwrap.c.
Remove endgrent() call until somebody can explain why it was there.

1 files changed, 2 insertions, 1 deletions

diff --git a/main.c b/main.c
index 7355f0a2..8fe8e058 100644
--- a/main.c
+++ b/main.c
@@ -92,7 +92,8 @@ void toy_init(struct toy_list *which, char *argv[])
     uid_t uid = getuid(), euid = geteuid();
 
     if (!(which->flags & TOYFLAG_STAYROOT)) {
-      if (uid != euid) xsetuid(euid=uid); // drop root
+      if (uid != euid)
+        if (!setuid(euid=uid)) perror_exit("setuid"); // drop root
     } else if (CFG_TOYBOX_DEBUG && uid && which != toy_list)
       error_msg("Not installed suid root");