Move btrfs_backups.sh to backup role dir

Move backup script to role directory rather than the root directory of
the roles.

ansible/arch_backup/files/scripts/btrfs_backup.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+export SOURCE_DIR=${SOURCE_DIR:=root}
+# Fix basename / showing up as "/" -> change to "root"
+if [ $(basename $SOURCE_DIR) = / ]; then
+    export SNAPSHOT_PREFIX=${SNAPSHOT_PREFIX:=root}
+else
+    export SNAPSHOT_PREFIX=${SNAPSHOT_PREFIX:=$(basename $SOURCE_DIR)}
+fi
+# Set snapshot prefix based on basename
+export SNAPSHOT_TIME=$(date +"%y_%m_%d-%H.%M")
+export SNAPSHOT_NAME=$SNAPSHOT_PREFIX-$SNAPSHOT_TIME
+export SNAPSHOT_DIR=${SNAPSHOT_DIR:=/.snapshots}
+export LATEST=$SNAPSHOT_PREFIX-latest
+export BACKUP_DRIVE_MNT=${BACKUP_DRIVE_MNT:=/mnt/backup0}
+export BACKUP_DIR=${BACKUP_DIR:=/mnt/backup0/DucoBacktop}
+
+# Show snapshot settings
+echo "SOURCE_DIR: $SOURCE_DIR"
+echo "SNAPSHOT_PREFIX: $SNAPSHOT_PREFIX"
+echo "SNAPSHOT_TIME: $SNAPSHOT_TIME"
+echo "SNAPSHOT_NAME: $SNAPSHOT_NAME"
+echo "SNAPSHOT_DIR: $SNAPSHOT_DIR"
+echo "LATEST: $LATEST"
+echo "BACKUP_DRIVE_MNT: $BACKUP_DRIVE_MNT"
+echo "BACKUP_DIR: $BACKUP_DIR"
+
+# Create readonly snapshot
+btrfs subvolume snapshot -r $SOURCE_DIR $SNAPSHOT_DIR/$SNAPSHOT_NAME
+
+# Check if backup disk is mounted
+mount $BACKUP_DRIVE_MNT
+mountpoint $BACKUP_DRIVE_MNT
+
+if [ $? = 0 ]; then
+    if [ -d $BACKUP_DIR/$LATEST ]; then
+        btrfs send -p $SNAPSHOT_DIR/$LATEST $SNAPSHOT_DIR/$SNAPSHOT_NAME | btrfs receive $BACKUP_DIR
+    else
+        btrfs send $SNAPSHOT_DIR/$SNAPSHOT_NAME | btrfs receive $BACKUP_DIR
+    fi
+
+    # Update latest in snapshot dir
+    rm -f $SNAPSHOT_DIR/$LATEST
+    ln -s $SNAPSHOT_DIR/$SNAPSHOT_NAME $SNAPSHOT_DIR/$LATEST
+    
+    # Update latest in backup dir
+    rm -f $BACKUP_DIR/$LATEST
+    ln -s $BACKUP_DIR/$SNAPSHOT_NAME $BACKUP_DIR/$LATEST
+else
+    echo "Backup location $BACKUP_DRIVE_MNT not mounted. Snapshot $SNAPSHOT_NAME not synced"
+fi