Introduce vfs_read_dirent() which can help VOP_READDIR() implementations

by handling all the cookie stuff.

2 files changed, 29 insertions, 0 deletions

diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 19dc538..461ed1a 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -49,6 +49,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/bio.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
+#include <sys/dirent.h>
 #include <sys/event.h>
 #include <sys/eventhandler.h>
 #include <sys/extattr.h>
@@ -3838,3 +3839,29 @@ filt_vfsvnode(struct knote *kn, long hint)
 	}
 	return (kn->kn_fflags != 0);
 }
+
+int
+vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
+{
+	int error;
+
+	if (dp->d_reclen > ap->a_uio->uio_resid)
+		return (ENAMETOOLONG);
+	error = uiomove(dp, dp->d_reclen, ap->a_uio);
+	if (error) {
+		if (ap->a_ncookies != NULL) {
+			if (ap->a_cookies != NULL)
+				free(ap->a_cookies, M_TEMP);
+			ap->a_cookies = NULL;
+			*ap->a_ncookies = 0;
+		}
+		return (error);
+	}
+	if (ap->a_ncookies == NULL)
+		return (0);
+	*ap->a_cookies = realloc(*ap->a_cookies,
+	    (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
+	(*ap->a_cookies)[*ap->a_ncookies] = off;
+	return (0);
+}
+
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 98b2348..52a1d2f 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -727,6 +727,8 @@ void vfs_hash_rehash(struct vnode *vp, u_int hash);
 void vfs_hash_remove(struct vnode *vp);
 
 int vfs_kqfilter(struct vop_kqfilter_args *);
+struct dirent;
+int vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off);
 
 #endif /* _KERNEL */