[src/trunk]: src/sys/kern use sbcreatecontrol1() and m_add() instead of open-...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c1955878ffd5
branches:  trunk
changeset: 787650:c1955878ffd5
user:      christos <christos%NetBSD.org@localhost>
date:      Thu Jun 27 18:54:31 2013 +0000

description:
use sbcreatecontrol1() and m_add() instead of open-coding everything, and
getting it slightly wrong.

diffstat:

 sys/kern/uipc_usrreq.c |  52 ++++++++++++-------------------------------------
 1 files changed, 13 insertions(+), 39 deletions(-)

diffs (82 lines):

diff -r 8c559bc96a5f -r c1955878ffd5 sys/kern/uipc_usrreq.c
--- a/sys/kern/uipc_usrreq.c    Thu Jun 27 18:53:17 2013 +0000
+++ b/sys/kern/uipc_usrreq.c    Thu Jun 27 18:54:31 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_usrreq.c,v 1.141 2013/02/14 01:00:07 riastradh Exp $      */
+/*     $NetBSD: uipc_usrreq.c,v 1.142 2013/06/27 18:54:31 christos Exp $       */
 
 /*-
  * Copyright (c) 1998, 2000, 2004, 2008, 2009 The NetBSD Foundation, Inc.
@@ -96,7 +96,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_usrreq.c,v 1.141 2013/02/14 01:00:07 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_usrreq.c,v 1.142 2013/06/27 18:54:31 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1465,52 +1465,26 @@
 struct mbuf *
 unp_addsockcred(struct lwp *l, struct mbuf *control)
 {
-       struct cmsghdr *cmp;
        struct sockcred *sc;
-       struct mbuf *m, *n;
-       int len, space, i;
-
-       len = CMSG_LEN(SOCKCREDSIZE(kauth_cred_ngroups(l->l_cred)));
-       space = CMSG_SPACE(SOCKCREDSIZE(kauth_cred_ngroups(l->l_cred)));
+       struct mbuf *m;
+       void *p;
 
-       m = m_get(M_WAIT, MT_CONTROL);
-       if (space > MLEN) {
-               if (space > MCLBYTES)
-                       MEXTMALLOC(m, space, M_WAITOK);
-               else
-                       m_clget(m, M_WAIT);
-               if ((m->m_flags & M_EXT) == 0) {
-                       m_free(m);
-                       return (control);
-               }
-       }
-
-       m->m_len = space;
-       m->m_next = NULL;
-       cmp = mtod(m, struct cmsghdr *);
-       sc = (struct sockcred *)CMSG_DATA(cmp);
-       cmp->cmsg_len = len;
-       cmp->cmsg_level = SOL_SOCKET;
-       cmp->cmsg_type = SCM_CREDS;
+       m = sbcreatecontrol1(&p, SOCKCREDSIZE(kauth_cred_ngroups(l->l_cred)),
+               SCM_CREDS, SOL_SOCKET, M_WAITOK);
+       if (m == NULL)
+               return control;
+               
+       sc = p;
        sc->sc_uid = kauth_cred_getuid(l->l_cred);
        sc->sc_euid = kauth_cred_geteuid(l->l_cred);
        sc->sc_gid = kauth_cred_getgid(l->l_cred);
        sc->sc_egid = kauth_cred_getegid(l->l_cred);
        sc->sc_ngroups = kauth_cred_ngroups(l->l_cred);
-       for (i = 0; i < sc->sc_ngroups; i++)
+
+       for (int i = 0; i < sc->sc_ngroups; i++)
                sc->sc_groups[i] = kauth_cred_group(l->l_cred, i);
 
-       /*
-        * If a control message already exists, append us to the end.
-        */
-       if (control != NULL) {
-               for (n = control; n->m_next != NULL; n = n->m_next)
-                       ;
-               n->m_next = m;
-       } else
-               control = m;
-
-       return (control);
+       return m_add(control, m);
 }
 
 /*