From 4072f1cf769d51d0ca066d83b0e921cf3ec74bb6 Mon Sep 17 00:00:00 2001
From: ed <ed@FreeBSD.org>
Date: Wed, 29 Jul 2015 17:16:53 +0000
Subject: [PATCH] Introduce falloc_caps() to create descriptors with
 capabilties in place.

falloc_noinstall() followed by finstall() allows you to create and
install file descriptors with custom capabilities. Add falloc_caps()
that can do both of these actions in one go.

This will be used by CloudABI to create pipes with custom capabilities.

Reviewed by:	mjg
---
 sys/kern/kern_descrip.c | 5 +++--
 sys/sys/filedesc.h      | 8 ++++++--
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index 933e4cc5cc81..dc0ee49c3851 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -1707,7 +1707,8 @@ fdallocn(struct thread *td, int minfd, int *fds, int n)
  * release the FILEDESC lock.
  */
 int
-falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags)
+falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags,
+    struct filecaps *fcaps)
 {
 	struct file *fp;
 	int error, fd;
@@ -1716,7 +1717,7 @@ falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags)
 	if (error)
 		return (error);		/* no reference held on error */
 
-	error = finstall(td, fp, &fd, flags, NULL);
+	error = finstall(td, fp, &fd, flags, fcaps);
 	if (error) {
 		fdrop(fp, td);		/* one reference (fp only) */
 		return (error);
diff --git a/sys/sys/filedesc.h b/sys/sys/filedesc.h
index b557706bb04e..f75927b86b72 100644
--- a/sys/sys/filedesc.h
+++ b/sys/sys/filedesc.h
@@ -146,6 +146,10 @@ enum {
 /* Flags for kern_dup(). */
 #define	FDDUP_FLAG_CLOEXEC	0x1	/* Atomically set UF_EXCLOSE. */
 
+/* For backward compatibility. */
+#define	falloc(td, resultfp, resultfd, flags) \
+	falloc_caps(td, resultfp, resultfd, flags, NULL)
+
 struct thread;
 
 void	filecaps_init(struct filecaps *fcaps);
@@ -156,8 +160,8 @@ void	filecaps_free(struct filecaps *fcaps);
 int	closef(struct file *fp, struct thread *td);
 int	dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode,
 	    int openerror, int *indxp);
-int	falloc(struct thread *td, struct file **resultfp, int *resultfd,
-	    int flags);
+int	falloc_caps(struct thread *td, struct file **resultfp, int *resultfd,
+	    int flags, struct filecaps *fcaps);
 int	falloc_noinstall(struct thread *td, struct file **resultfp);
 void	_finstall(struct filedesc *fdp, struct file *fp, int fd, int flags,
 	    struct filecaps *fcaps);