Address problems identified by shellcheck

Author: cfra

entrypoint.sh

@@ -6,4 +6,8 @@
 # the host's git-config, which is not necessarily the location where the
 # wrapper script is installed.
 #
-exec -a "git-crypt" /usr/bin/git-crypt "$@"
+
+PATH="$PATH:/usr/bin"
+export PATH
+
+exec git-crypt "$@"

wrapper.sh

@@ -11,7 +11,7 @@ set -e
 # On some calls, git will pass along a temporary file to git-crypt.
 # For this to work, we need to mount this file into the container.
 #
-if [ -n "$2" ] && [ "${2:0:1}" = "/" ]; then
+if [ -n "$2" ] && [ "$(echo "$2" | cut -c1-1)" = "/" ]; then
     DOCKER_OPTS="--volume=$2:$2"
 fi
 
@@ -31,10 +31,12 @@ if [ x"$1" = x"unlock" ]; then
     DOCKER_OPTS="$DOCKER_OPTS -t"
 fi
 
+# We want to split the options and know there are no other spaces in them.
+# shellcheck disable=SC2086
 exec docker run \
         --rm \
         --interactive \
-        --user=$(id -u):$(id -g) \
+        --user="$(id -u):$(id -g)" \
         --volume="$(pwd)":/repo \
         ${DOCKER_OPTS} \
         quay.io/picturepipe/git-crypt "$@"