Refactor parent dataset handling in libzfs zfs_rename()

For recursive renaming, simplify the code by moving `zhrp` and
`parentname` to inner scope. `zhrp` is only used to test existence
of a parent dataset for recursive dataset dir scan since ba6a24026c.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Giuseppe Di Natale <guss80@gmail.com>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@osnexus.com>
Closes #8815

diff --git a/lib/libzfs/libzfs_dataset.c b/lib/libzfs/libzfs_dataset.c
index e26b32786db5f9ca22f855e5c8d76f0ae3a354d7..93af50b99cdd60ba547de539ea85b3ca0cadfd62 100644 (file)
--- a/lib/libzfs/libzfs_dataset.c
+++ b/lib/libzfs/libzfs_dataset.c
@@ -4470,8 +4470,6 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive,
        zfs_cmd_t zc = {"\0"};
        char *delim;
        prop_changelist_t *cl = NULL;
-       zfs_handle_t *zhrp = NULL;
-       char *parentname = NULL;
        char parent[ZFS_MAX_DATASET_NAME_LEN];
        libzfs_handle_t *hdl = zhp->zfs_hdl;
        char errbuf[1024];
@@ -4566,7 +4564,8 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive,
        }
 
        if (recursive) {
-               parentname = zfs_strdup(zhp->zfs_hdl, zhp->zfs_name);
+               zfs_handle_t *zhrp;
+               char *parentname = zfs_strdup(zhp->zfs_hdl, zhp->zfs_name);
                if (parentname == NULL) {
                        ret = -1;
                        goto error;
@@ -4574,10 +4573,12 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive,
                delim = strchr(parentname, '@');
                *delim = '\0';
                zhrp = zfs_open(zhp->zfs_hdl, parentname, ZFS_TYPE_DATASET);
+               free(parentname);
                if (zhrp == NULL) {
                        ret = -1;
                        goto error;
                }
+               zfs_close(zhrp);
        } else if (zhp->zfs_type != ZFS_TYPE_SNAPSHOT) {
                if ((cl = changelist_gather(zhp, ZFS_PROP_NAME,
                    CL_GATHER_ITER_MOUNTED,
@@ -4650,12 +4651,6 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive,
        }
 
 error:
-       if (parentname != NULL) {
-               free(parentname);
-       }
-       if (zhrp != NULL) {
-               zfs_close(zhrp);
-       }
        if (cl != NULL) {
                changelist_free(cl);
        }