fix btrfs-shrink

1 files changed, 10 insertions, 8 deletions

diff --git a/src/btrfs-utils/btrfs-shrink b/src/btrfs-utils/btrfs-shrink
index 229b478..4c4e40d 100755
--- a/src/btrfs-utils/btrfs-shrink
+++ b/src/btrfs-utils/btrfs-shrink
@@ -6,7 +6,7 @@ die() { printf "%s: Error: %s\n" "$0" "$*" >&2; exit 1; }
 
 shrink()
 {
-    shrinkmegs=100
+    local shrinkmegs=100 mountpoint="$1"
     while true; do
         while ! btrfs filesystem resize -${shrinkmegs}M "$mountpoint"/; do
             shrinkmegs=$((shrinkmegs - 10 ))
@@ -30,18 +30,20 @@ btrfs_truncate()
 main()
 {
     if [ -d "$1" ]; then
-        mountpoint -q "$1" || die "not a mountpoint: $1"
-        shrink "$1"
+        mountpoint=$1
+        mountpoint -q "$mountpoint" || die "not a mountpoint: $1"
+        shrink "$mountpoint"
     elif [ -f "$1" ]; then
-        mkdir "$1".mnt.tmp
-        mount -t btrfs "$1" "$1".mnt.tmp
+        mountpoint="$1".mnt.tmp
+        mkdir "$mountpoint"
+        mount -t btrfs "$1" "$mountpoint"
         result=$?
         if [ $result = 0 ]; then
-            shrink "$1".mnt.tmp
+            shrink "$mountpoint"
             result=$?
+            umount "$mountpoint"
         fi
-        umount "$1".mnt.tmp
-        rmdir "$1".mnt.tmp
+        rmdir "$mountpoint"
         btrfs_truncate "$1"
         return $result
     else