getdents(2)

1 files changed, 130 insertions, 0 deletions

diff --git a/sys/compat/netbsd/netbsd_getdents.c b/sys/compat/netbsd/netbsd_getdents.c
new file mode 100644
index 00000000000..2163c15442c
--- /dev/null
+++ b/sys/compat/netbsd/netbsd_getdents.c
@@ -0,0 +1,130 @@
+#include <sys/param.h>
+#include <sys/file.h>
+#include <sys/mount.h>
+#include <sys/proc.h>
+#include <sys/uio.h>
+#include <sys/vnode.h>
+
+#include <compat/netbsd/netbsd_signal.h>
+#include <compat/netbsd/netbsd_syscallargs.h>
+
+static int netbsd_vn_readdir __P((struct file *, char *, int, u_int, int *,
+	struct proc *, off_t **, int *));
+
+static int
+netbsd_vn_readdir(fp, buf, segflg, count, done, p, cookies, ncookies)
+	struct file *fp;
+	char *buf;
+	int segflg, *done, *ncookies;
+	u_int count;
+	struct proc *p;
+	off_t **cookies;
+{
+	struct vnode *vp = (struct vnode *)fp->f_data;
+	struct iovec aiov;
+	struct uio auio;
+	int error, eofflag;
+
+unionread:
+	if (vp->v_type != VDIR)
+		return (EINVAL);
+	aiov.iov_base = buf;
+	aiov.iov_len = count;
+	auio.uio_iov = &aiov;
+	auio.uio_iovcnt = 1;
+	auio.uio_rw = UIO_READ;
+	auio.uio_segflg = segflg;
+	auio.uio_procp = p;
+	auio.uio_resid = count;
+	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
+	auio.uio_offset = fp->f_offset;
+	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, ncookies,
+		    (u_long **)cookies); /* XXX 32-bit? */
+	fp->f_offset = auio.uio_offset;
+	VOP_UNLOCK(vp, 0, p);
+	if (error)
+		return (error);
+
+#ifdef UNION
+{
+	extern int (**union_vnodeop_p) __P((void *));
+	extern struct vnode *union_dircache __P((struct vnode *));
+
+	if (count == auio.uio_resid && (vp->v_op == union_vnodeop_p)) {
+		struct vnode *lvp;
+
+		lvp = union_dircache(vp);
+		if (lvp != NULLVP) {
+			struct vattr va;
+
+			/*
+			 * If the directory is opaque,
+			 * then don't show lower entries
+			 */
+			error = VOP_GETATTR(vp, &va, fp->f_cred, p);
+			if (va.va_flags & OPAQUE) {
+				vput(lvp);
+				lvp = NULL;
+			}
+		}
+		
+		if (lvp != NULLVP) {
+			error = VOP_OPEN(lvp, FREAD, fp->f_cred, p);
+			if (error) {
+				vput(lvp);
+				return (error);
+			}
+			VOP_UNLOCK(lvp, 0);
+			fp->f_data = (caddr_t) lvp;
+			fp->f_offset = 0;
+			error = vn_close(vp, FREAD, fp->f_cred, p);
+			if (error)
+				return (error);
+			vp = lvp;
+			goto unionread;
+		}
+	}
+}
+#endif /* UNION */
+
+	if (count == auio.uio_resid && (vp->v_flag & VROOT) &&
+	    (vp->v_mount->mnt_flag & MNT_UNION)) {
+		struct vnode *tvp = vp;
+		vp = vp->v_mount->mnt_vnodecovered;
+		VREF(vp);
+		fp->f_data = (caddr_t) vp;
+		fp->f_offset = 0;
+		vrele(tvp);
+		goto unionread;
+	}
+	*done = count - auio.uio_resid;
+	return error;
+}
+
+/*
+ * Read a block of directory entries in a file system independent format.
+ */
+int
+netbsd_sys_getdents(p, v, retval)
+	struct proc *p;
+	void *v;
+	register_t *retval;
+{
+	register struct netbsd_sys_getdents_args /* {
+		syscallarg(int) fd;
+		syscallarg(char *) buf;
+		syscallarg(size_t) count;
+	} */ *uap = v;
+	struct file *fp;
+	int error, done;
+
+	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
+		return (error);
+	if ((fp->f_flag & FREAD) == 0)
+		return (EBADF);
+	error = netbsd_vn_readdir(fp, SCARG(uap, buf), UIO_USERSPACE,
+			SCARG(uap, count), &done, p, 0, 0);
+	*retval = done;
+	return (error);
+}
+