Hardcode version, add a release script

Having thought about this more, I am semi-reverting
fcd4d58 in favor of hardcoding the
version to the binary and a release script.

Makefile

@@ -1,4 +1,4 @@
-FILES = btrfs-auto-snapshot
+FILES = btrfs-auto-snapshot release
 
 .PHONY: lint
 lint: shfmt shellcheck

btrfs-auto-snapshot

@@ -24,9 +24,7 @@ set -euo pipefail
 #set -o functrace
 #set -o xtrace
 
-# Define our version. Distributions may replace it with:
-#   sed -i 's/^\(BTRFS_AUTO_SNAPSHOT_VERSION\)=.*/\1=<version>/' <file>
-BTRFS_AUTO_SNAPSHOT_VERSION=${BTRFS_AUTO_SNAPSHOT_VERSION:-unknown}
+BTRFS_AUTO_SNAPSHOT_VERSION=v2.0.4+dev
 
 # Define various error codes
 ERR_SUCCESS=0

release

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+log_run()
+{
+    echo >&2 "+ $*"
+    "$@"
+}
+
+main()
+{
+    VERSION=$1
+    if [[ ! $VERSION =~ ^v[0-9]\.[0-9]\.[0-9]$ ]]; then
+            echo >&2 "Invalid version. Expected v1.2.3 or so"
+        exit 1
+    fi
+
+    log_run sed -i'' 's/^\(BTRFS_AUTO_SNAPSHOT_VERSION\)=.*/\1='"$VERSION/" btrfs-auto-snapshot
+    log_run git add btrfs-auto-snapshot
+    log_run git commit -m "Release $VERSION"
+    log_run git tag "$VERSION"
+    log_run sed -i'' 's/^\(BTRFS_AUTO_SNAPSHOT_VERSION\)=.*/\1='"$VERSION+dev/" btrfs-auto-snapshot
+    log_run git add btrfs-auto-snapshot
+    log_run git commit -m "$VERSION+dev"
+    echo "You have tagged $VERSION. Now run the following:"
+    echo "  git push origin master"
+    echo "  git push origin $VERSION"
+}
+
+main "$@"