New system call: getdtablecount(2) returns the number of file

descriptors the process currently has open.
ok guenther miod gilles ...

3 files changed, 14 insertions, 4 deletions

diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index ef18b8bef87..dca42ddc9d7 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_descrip.c,v 1.90 2012/04/12 11:01:37 deraadt Exp $	*/
+/*	$OpenBSD: kern_descrip.c,v 1.91 2012/04/12 11:07:20 deraadt Exp $	*/
 /*	$NetBSD: kern_descrip.c,v 1.42 1996/03/30 22:24:38 christos Exp $	*/
 
 /*
@@ -155,6 +155,7 @@ fd_used(struct filedesc *fdp, int fd)
 
 	if (fd > fdp->fd_lastfile)
 		fdp->fd_lastfile = fd;
+	fdp->fd_openfd++;
 }
 
 static __inline void
@@ -175,6 +176,7 @@ fd_unused(struct filedesc *fdp, int fd)
 #endif
 	if (fd == fdp->fd_lastfile)
 		fdp->fd_lastfile = find_last_set(fdp, fd);
+	fdp->fd_openfd--;
 }
 
 struct file *
@@ -1320,3 +1322,10 @@ sys_closefrom(struct proc *p, void *v, register_t *retval)
 	fdpunlock(fdp);
 	return (0);
 }
+
+int
+sys_getdtablecount(struct proc *p, void *v, register_t *retval)
+{
+	*retval = p->p_fd->fd_openfd;
+	return (0);
+}
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index af289aab619..c241438c611 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -1,4 +1,4 @@
-;	$OpenBSD: syscalls.master,v 1.120 2012/01/17 02:34:18 guenther Exp $
+;	$OpenBSD: syscalls.master,v 1.121 2012/04/12 11:07:19 deraadt Exp $
 ;	$NetBSD: syscalls.master,v 1.32 1996/04/23 10:24:21 mycroft Exp $
 
 ;	@(#)syscalls.master	8.2 (Berkeley) 1/13/94
@@ -72,7 +72,7 @@
 16	STD		{ int sys_chown(const char *path, uid_t uid, \
 			    gid_t gid); }
 17	STD		{ int sys_obreak(char *nsize); } break
-18	OBSOL		getfsstat25
+18	STD		{ int sys_getdtablecount(void); }
 19	OBSOL		olseek
 20	STD NOLOCK	{ pid_t sys_getpid(void); }
 21	STD		{ int sys_mount(const char *type, const char *path, \
diff --git a/sys/sys/filedesc.h b/sys/sys/filedesc.h
index 876b3bb6b14..92de6f3040e 100644
--- a/sys/sys/filedesc.h
+++ b/sys/sys/filedesc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: filedesc.h,v 1.21 2012/02/15 04:26:27 guenther Exp $	*/
+/*	$OpenBSD: filedesc.h,v 1.22 2012/04/12 11:07:19 deraadt Exp $	*/
 /*	$NetBSD: filedesc.h,v 1.14 1996/04/09 20:55:28 cgd Exp $	*/
 
 /*
@@ -62,6 +62,7 @@ struct filedesc {
 	struct	vnode *fd_cdir;		/* current directory */
 	struct	vnode *fd_rdir;		/* root directory */
 	int	fd_nfiles;		/* number of open files allocated */
+	int	fd_openfd;		/* number of files currently open */
 	u_int	*fd_himap;		/* each bit points to 32 fds */
 	u_int	*fd_lomap;		/* bitmap of free fds */
 	int	fd_lastfile;		/* high-water mark of fd_ofiles */