Adds support for property overrides (WIP)

Adds support for property overrides (-o property=value), property
excludes (-x property) and dataset limits (-l <volume|filesystem>)
to zfs receive.

Both -o and -x options mirror the functionality already available
in Oracle's ZFS implementation which is also mentioned in the
upstream feature request openzfs#2745:

The -l option allows receive to be limited to specific datasets within
the stream effectively allowing partial restores from a multi dataset
stream.

References:
  https://www.illumos.org/issues/2745

Ported-by: Milan-Benes
Issue openzfs#1350

NOTES: Man page updates missing and must be added, see patch:
http://blog.multiplay.co.uk/dropzone/freebsd/zfs-recv-properties.patch

cmd/zfs/zfs_main.c

@@ -244,9 +244,9 @@ get_usage(zfs_help_t idx)
 	case HELP_PROMOTE:
 		return (gettext("\tpromote <clone-filesystem>\n"));
 	case HELP_RECEIVE:
-		return (gettext("\treceive [-vnFu] <filesystem|volume|"
-		"snapshot>\n"
-		"\treceive [-vnFu] [-d | -e] <filesystem>\n"));
+		return (gettext("\treceive [-vnFu] [-d | -e] [-o <property>] "
+		    "... [-x <property>] ... [-l <filesystem|volume>] ... "
+		    " <filesystem|volume|snapshot>\n"));
 	case HELP_RENAME:
 		return (gettext("\trename [-f] <filesystem|volume|snapshot> "
 		    "<filesystem|volume|snapshot>\n"
@@ -469,6 +469,21 @@ usage(boolean_t requested)
 	exit(requested ? 0 : 2);
 }
 
+static int
+parsepropname(nvlist_t *props)
+{
+	char *propname = optarg;
+
+	if (nvlist_lookup_string(props, propname, NULL) == 0) {
+		(void) fprintf(stderr, gettext("property '%s' "
+		    "specified multiple times\n"), propname);
+		return (-1);
+	}
+	if (nvlist_add_boolean(props, propname))
+		nomem();
+	return (0);
+}
+
 static int
 parseprop(nvlist_t *props)
 {
@@ -3727,18 +3742,24 @@ zfs_do_send(int argc, char **argv)
 }
 
 /*
- * zfs receive [-vnFu] [-d | -e] <fs@snap>
+ * zfs receive [-vnFu] [-d | -e] [-l <volume|filesystem>] ...
+ * [-o property=value] ... [-x property] ... <volume|filesytem|snapshot>
  *
  * Restore a backup stream from stdin.
  */
 static int
 zfs_do_receive(int argc, char **argv)
 {
+	nvlist_t *props, *limitds;
 	int c, err;
 	recvflags_t flags = { 0 };
+	if (nvlist_alloc(&props, NV_UNIQUE_NAME, 0) != 0)
+		nomem();
+	if (nvlist_alloc(&limitds, NV_UNIQUE_NAME, 0) != 0)
+		nomem();
 
 	/* check options */
-	while ((c = getopt(argc, argv, ":denuvF")) != -1) {
+	while ((c = getopt(argc, argv, ":del:no:uvx:F")) != -1) {
 		switch (c) {
 		case 'd':
 			flags.isprefix = B_TRUE;
@@ -3747,15 +3768,32 @@ zfs_do_receive(int argc, char **argv)
 			flags.isprefix = B_TRUE;
 			flags.istail = B_TRUE;
 			break;
+		case 'l':
+			if (parsepropname(limitds)) {
+				err = 1;
+				goto recverror;
+			}
+			break;
 		case 'n':
 			flags.dryrun = B_TRUE;
 			break;
+		case 'o':
+			if (parseprop(props)) {
+				err = 1;
+				goto recverror;
+			}
+			break;
 		case 'u':
 			flags.nomount = B_TRUE;
 			break;
 		case 'v':
 			flags.verbose = B_TRUE;
 			break;
+		case 'x':
+			if (parsepropname(props)) {
+				err = 1;
+				goto recverror;
+			}
 		case 'F':
 			flags.force = B_TRUE;
 			break;
@@ -3792,7 +3830,24 @@ zfs_do_receive(int argc, char **argv)
 		return (1);
 	}
 
-	err = zfs_receive(g_zfs, argv[0], &flags, STDIN_FILENO, NULL);
+	if (nvlist_empty(props)) {
+		nvlist_free(props);
+		props = NULL;
+	}
+
+	if (nvlist_empty(limitds)) {
+		nvlist_free(limitds);
+		limitds = NULL;
+	}
+
+	err = zfs_receive(g_zfs, argv[0], &flags, STDIN_FILENO, props, limitds, NULL);
+
+recverror:
+	if (props != NULL)
+		nvlist_free(props);
+
+	if (limitds != NULL)
+		nvlist_free(limitds);
 
 	return (err != 0);
 }

include/libzfs.h

@@ -660,7 +660,7 @@ typedef struct recvflags {
 } recvflags_t;
 
 extern int zfs_receive(libzfs_handle_t *, const char *, recvflags_t *,
-    int, avl_tree_t *);
+    int, nvlist_t *, nvlist_t *, avl_tree_t *);
 
 typedef enum diff_flags {
 	ZFS_DIFF_PARSEABLE = 0x1,

include/libzfs_impl.h

@@ -187,6 +187,8 @@ int changelist_haszonedchild(prop_changelist_t *);
 
 void remove_mountpoint(zfs_handle_t *);
 int create_parents(libzfs_handle_t *, char *, int);
+int check_parents(libzfs_handle_t *hdl, const char *path, uint64_t *zoned,
+    boolean_t accept_ancestor, int *prefixlen);
 boolean_t isa_child_of(const char *dataset, const char *parent);
 
 zfs_handle_t *make_dataset_handle(libzfs_handle_t *, const char *);

lib/libzfs/libzfs_dataset.c

@@ -2759,7 +2759,7 @@ parent_name(const char *path, char *buf, size_t buflen)
  * 'zoned' property, which is used to validate property settings when creating
  * new datasets.
  */
-static int
+int
 check_parents(libzfs_handle_t *hdl, const char *path, uint64_t *zoned,
     boolean_t accept_ancestor, int *prefixlen)
 {