Moving bitcoin to build role

roles/build/files/bitcoin/bin/btc_oneshot

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+set -ex
+
+# Generate bitcoin.conf
+btc_init
+
+# Default / no argument invocation listens for RPC commands and has to accept non-localhost because of
+# Docker port proxying or Docker private networking.
+if [ $# -eq 0 ]; then
+    # If IPv6 is in the container do both:
+    #set -- '-rpcbind=[::]:8332' '-rpcallowip=::/0' '-rpcallowip=0.0.0.0/0'
+    set -- '-rpcbind=:8332' '-rpcallowip=0.0.0.0/0'
+fi
+
+exec bitcoind "$@"

roles/build/files/bitcoin/entrypoint.sh

@@ -0,0 +1,18 @@
+#!/bin/sh
+set -e
+
+# first arg is `-f` or `--some-option`
+# or first arg is `something.conf`
+if [ "${1#-}" != "$1" ] || [ "${1%.conf}" != "$1" ]; then
+	set -- btc_oneshot "$@"
+fi
+
+# Allow the container to be started with `--user`, if running as root drop privileges
+if [ "$1" = 'btc_oneshot' -a "$(id -u)" = '0' ]; then
+	chown -R bitcoin .
+	exec gosu bitcoin "$0" "$@"
+fi
+
+# If not root (i.e. docker run --user $USER ...), then run as invoked
+exec "$@"
+