zfs label bootenv should store data as nvlist

nvlist does allow us to support different data types and systems.

To encapsulate user data to/from nvlist, the libzfsbootenv library is
provided.

Reviewed-by: Arvind Sankar <[email protected]>
Reviewed-by: Allan Jude <[email protected]>
Reviewed-by: Paul Dagnelie <[email protected]>
Reviewed-by: Igor Kozhukhov <[email protected]>
Signed-off-by: Toomas Soome <[email protected]>
Closes #10774 

1 files changed, 10 insertions, 14 deletions

diff --git a/lib/libzfs/libzfs_pool.c b/lib/libzfs/libzfs_pool.c
index 2501965e4..00b0b6faf 100644
--- a/lib/libzfs/libzfs_pool.c
+++ b/lib/libzfs/libzfs_pool.c
@@ -4495,7 +4495,7 @@ zpool_wait_status(zpool_handle_t *zhp, zpool_wait_activity_t activity,
 }
 
 int
-zpool_set_bootenv(zpool_handle_t *zhp, const char *envmap)
+zpool_set_bootenv(zpool_handle_t *zhp, const nvlist_t *envmap)
 {
 	int error = lzc_set_bootenv(zhp->zpool_name, envmap);
 	if (error != 0) {
@@ -4508,24 +4508,20 @@ zpool_set_bootenv(zpool_handle_t *zhp, const char *envmap)
 }
 
 int
-zpool_get_bootenv(zpool_handle_t *zhp, char *outbuf, size_t size, off_t offset)
+zpool_get_bootenv(zpool_handle_t *zhp, nvlist_t **nvlp)
 {
-	nvlist_t *nvl = NULL;
-	int error = lzc_get_bootenv(zhp->zpool_name, &nvl);
+	nvlist_t *nvl;
+	int error;
+
+	nvl = NULL;
+	error = lzc_get_bootenv(zhp->zpool_name, &nvl);
 	if (error != 0) {
 		(void) zpool_standard_error_fmt(zhp->zpool_hdl, error,
 		    dgettext(TEXT_DOMAIN,
 		    "error getting bootenv in pool '%s'"), zhp->zpool_name);
-		return (-1);
-	}
-	char *envmap = fnvlist_lookup_string(nvl, "envmap");
-	if (offset >= strlen(envmap)) {
-		fnvlist_free(nvl);
-		return (0);
+	} else {
+		*nvlp = nvl;
 	}
 
-	strncpy(outbuf, envmap + offset, size);
-	int bytes = MIN(strlen(envmap + offset), size);
-	fnvlist_free(nvl);
-	return (bytes);
+	return (error);
 }