diskman.sh: small improvements

lib/diskman.sh

@@ -13,11 +13,18 @@
 # Blank the given disks
 blank_disk()
 {
-    if [[ $(test -b /dev/$1) ]]; then
+    if [[ -b /dev/$1 ]]; then
         prnt I "Wipping $1 drive signature (a backup is made in /root)..."
         wipefs --force --all --backup /dev/$1
         prnt I "Filling beginning of $1 drive with zeroes..."
-        dd if="/dev/zero" of="$1" bs="512" count="1024"
+        if [[ $2 == "--full" ]]; then
+            # If full we display progress as it might take a very long time
+            # Need true to avoid error as the last byte will generate a disk
+            # full error
+            dd if="/dev/zero" of="$1" bs="512" status=progress || true
+        else
+            dd if="/dev/zero" of="$1" bs="512" count="1024"
+        fi
 
         # Update kernel partition scheme
         partprobe
@@ -29,16 +36,23 @@ blank_disk()
 
 
 # ------------------------------------------------------------------------------
-# Check if $1 is a block device and if it's blank
+# Check if $1 is a blank block device. Return values:
+# * 0 if empty block device
+# * 1 if not empty block device
+# * 2 if not block device or if it don't exists
 is_blank()
 {
-    # That technique is fast but might not be relayable enough if we are on
+    if [[ -b /dev/$1 ]]; then
-    # exotic data structure or filesystem...
+        # That technique is fast but might not be relayable enough if we are on
-    local devstat=$(file /dev/$1 | sed "s@/dev/$1: @@")
+        # exotic data structure or filesystem...
-    if [[ $devstat == 'data' ]]; then
+        local devstat=$(file /dev/$1 | sed "s@/dev/$1: @@")
-        return 0
+        if [[ $devstat == 'data' ]]; then
+            return 0
+        else
+            return 1
+        fi
     else
-        return 1
+        return 2
     fi
 }