[PATCH RESEND] btrfs-progs: allow "no" to disable compression for convenience

[Satoru Takeuchi <satoru.takeuchi@gmail.com>]

It's messy to use "" to disable compression. Introduce the new value "no"
which can also be used for this purpose.

Signed-off-by: Satoru Takeuchi <satoru.takeuchi@gmail.com>
---
 Documentation/btrfs-property.asciidoc | 2 +-
 props.c                               | 6 ++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/Documentation/btrfs-property.asciidoc b/Documentation/btrfs-property.asciidoc
index 7ed6a7d..97b90d6 100644
--- a/Documentation/btrfs-property.asciidoc
+++ b/Documentation/btrfs-property.asciidoc
@@ -43,7 +43,7 @@ read-only flag of subvolume: true or false
 label::::
 label of device
 compression::::
-compression setting for an inode: lzo, zlib, zstd, or "" (empty string)
+compression setting for an inode: lzo, zlib, zstd, no, or "" (empty string). Both no and "" are for disabling compression.
 
 *list* [-t <type>] <object>::
 Lists available properties with their descriptions for the given object.
diff --git a/props.c b/props.c
index a7e3e96..a2df868 100644
--- a/props.c
+++ b/props.c
@@ -142,9 +142,11 @@ static int prop_compression(enum prop_object_type type,
 	memcpy(xattr_name + XATTR_BTRFS_PREFIX_LEN, name, strlen(name));
 	xattr_name[XATTR_BTRFS_PREFIX_LEN + strlen(name)] = '\0';
 
-	if (value)
+	if (value) {
+		if (!strcmp(value, "no"))
+			value = "";
 		sret = fsetxattr(fd, xattr_name, value, strlen(value), 0);
-	else
+	} else
 		sret = fgetxattr(fd, xattr_name, NULL, 0);
 	if (sret < 0) {
 		ret = -errno;
-- 
2.7.4