Module Name: src
Committed By: christos
Date: Mon Jul 30 10:42:24 UTC 2012
Modified Files:
src/sys/kern: uipc_usrreq.c
Log Message:
simplify unp_externalize(), some from gimpy, some from me.
To generate a diff of this commit:
cvs rdiff -u -r1.137 -r1.138 src/sys/kern/uipc_usrreq.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/uipc_usrreq.c
diff -u src/sys/kern/uipc_usrreq.c:1.137 src/sys/kern/uipc_usrreq.c:1.138
--- src/sys/kern/uipc_usrreq.c:1.137 Sat Jun 2 12:16:16 2012
+++ src/sys/kern/uipc_usrreq.c Mon Jul 30 06:42:24 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: uipc_usrreq.c,v 1.137 2012/06/02 16:16:16 martin Exp $ */
+/* $NetBSD: uipc_usrreq.c,v 1.138 2012/07/30 10:42:24 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 1.137 2012/06/02 16:16:16 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_usrreq.c,v 1.138 2012/07/30 10:42:24 christos Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -1235,25 +1235,22 @@ unp_drain(void)
int
unp_externalize(struct mbuf *rights, struct lwp *l, int flags)
{
- struct cmsghdr *cm = mtod(rights, struct cmsghdr *);
- struct proc *p = l->l_proc;
- int i, *fdp;
+ struct cmsghdr * const cm = mtod(rights, struct cmsghdr *);
+ struct proc * const p = l->l_proc;
file_t **rp;
- file_t *fp;
- int nfds, error = 0;
+ int error = 0;
- nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) /
+ const size_t nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) /
sizeof(file_t *);
- rp = (file_t **)CMSG_DATA(cm);
- fdp = malloc(nfds * sizeof(int), M_TEMP, M_WAITOK);
+ int * const fdp = kmem_alloc(nfds * sizeof(int), KM_SLEEP);
rw_enter(&p->p_cwdi->cwdi_lock, RW_READER);
/* Make sure the recipient should be able to see the files.. */
if (p->p_cwdi->cwdi_rdir != NULL) {
rp = (file_t **)CMSG_DATA(cm);
- for (i = 0; i < nfds; i++) {
- fp = *rp++;
+ for (size_t i = 0; i < nfds; i++) {
+ file_t * const fp = *rp++;
/*
* If we are in a chroot'ed directory, and
* someone wants to pass us a directory, make
@@ -1265,7 +1262,7 @@ unp_externalize(struct mbuf *rights, str
if ((vp->v_type == VDIR) &&
!vn_isunder(vp, p->p_cwdi->cwdi_rdir, l)) {
error = EPERM;
- break;
+ goto out;
}
}
}
@@ -1273,40 +1270,30 @@ unp_externalize(struct mbuf *rights, str
restart:
rp = (file_t **)CMSG_DATA(cm);
- if (error != 0) {
- for (i = 0; i < nfds; i++) {
- fp = *rp;
- *rp++ = 0;
- unp_discard_now(fp);
- }
- goto out;
- }
-
/*
* First loop -- allocate file descriptor table slots for the
* new files.
*/
- for (i = 0; i < nfds; i++) {
- fp = *rp++;
+ for (size_t i = 0; i < nfds; i++) {
if ((error = fd_alloc(p, 0, &fdp[i])) != 0) {
/*
* Back out what we've done so far.
*/
- for (--i; i >= 0; i--) {
+ while (i-- > 0) {
fd_abort(p, NULL, fdp[i]);
}
if (error == ENOSPC) {
fd_tryexpand(p);
error = 0;
- } else {
- /*
- * This is the error that has historically
- * been returned, and some callers may
- * expect it.
- */
- error = EMSGSIZE;
+ goto restart;
}
- goto restart;
+ /*
+ * This is the error that has historically
+ * been returned, and some callers may
+ * expect it.
+ */
+ error = EMSGSIZE;
+ goto out;
}
}
@@ -1315,12 +1302,17 @@ unp_externalize(struct mbuf *rights, str
* file passing state and affix the descriptors.
*/
rp = (file_t **)CMSG_DATA(cm);
- for (i = 0; i < nfds; i++) {
- int fd = fdp[i];
- fp = *rp++;
+ int *ofdp = (int *)CMSG_DATA(cm);
+ for (size_t i = 0; i < nfds; i++) {
+ file_t * const fp = *rp++;
+ const int fd = fdp[i];
atomic_dec_uint(&unp_rights);
fd_set_exclose(l, fd, (flags & O_CLOEXEC) != 0);
fd_affix(p, fp, fd);
+ /*
+ * Done with this file pointer, replace it with a fd;
+ */
+ *ofdp++ = fd;
mutex_enter(&fp->f_lock);
fp->f_msgcount--;
mutex_exit(&fp->f_lock);
@@ -1334,15 +1326,26 @@ unp_externalize(struct mbuf *rights, str
}
/*
- * Copy temporary array to message and adjust length, in case of
- * transition from large file_t pointers to ints.
+ * Adjust length, in case of transition from large file_t
+ * pointers to ints.
*/
- memcpy(CMSG_DATA(cm), fdp, nfds * sizeof(int));
- cm->cmsg_len = CMSG_LEN(nfds * sizeof(int));
- rights->m_len = CMSG_SPACE(nfds * sizeof(int));
+ if (sizeof(file_t *) != sizeof(int)) {
+ cm->cmsg_len = CMSG_LEN(nfds * sizeof(int));
+ rights->m_len = CMSG_SPACE(nfds * sizeof(int));
+ }
out:
+ if (__predict_false(error != 0)) {
+ rp = (file_t **)CMSG_DATA(cm);
+ for (size_t i = 0; i < nfds; i++) {
+ file_t * const fp = *rp;
+ *rp++ = 0;
+ unp_discard_now(fp);
+ }
+ goto out;
+ }
+
rw_exit(&p->p_cwdi->cwdi_lock);
- free(fdp, M_TEMP);
+ kmem_free(fdp, nfds * sizeof(int));
return (error);
}
