#! /bin/bash
#
# Sandstorm - Personal Cloud Sandbox
# Copyright (c) 2014 Sandstorm Development Group, Inc. and contributors
# All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

set -euo pipefail

rm -rf bundle

copyDep() {
  # Copies a file from the system into the chroot.
  
  local FILE=$1
  local DST=bundle"${FILE/#\/usr\/local/\/usr}"
  
  if [ -e "$DST" ]; then
    # already copied
    :
  elif [[ "$FILE" == /etc/* ]]; then
    # We'll want to copy configuration (e.g. for DNS) from the host at runtime.
    if [ -f "$FILE" ]; then
      echo "$FILE" >> tmp/etc.list
    fi
  elif [ -h "$FILE" ]; then
    # Symbolic link.
    # We copy over the target, and recreate the link.
    # Currently we denormalize the link because I'm not sure how to follow
    # one link at a time in bash (since readlink without -f gives a relative
    # path and I'm not sure how to interpret that against the link's path).
    # I'm sure there's a way, but whatever...
    mkdir -p $(dirname "$DST")
    local LINK=$(readlink -f "$FILE")
    ln -sf "${LINK/#\/usr\/local/\/usr}" "$DST"
    copyDep "$LINK"
  elif [ -d "$FILE" ]; then
    # Directory.  Make it, but don't copy contents; we'll do that later.
    mkdir -p "$DST"
  elif [ -f "$FILE" ]; then
    # Regular file.  Copy it over.
    mkdir -p $(dirname "$DST")
    cp "$FILE" "$DST"
  fi
}

copyDeps() {
  # Reads filenames on stdin and copies them into the chroot.

  while read FILE; do
    copyDep "$FILE"
  done
}

METEOR=$HOME/.meteor
METEOR_RELEASE=$(<shell/.meteor/release)
METEOR_TOOLS=$METEOR/tools/$(json tools < $METEOR/releases/$METEOR_RELEASE.release.json)

# Start with the meteor bundle.
cp -r shell-bundle bundle
rm bundle/README

# Copy over key binaries.
mkdir -p bundle/bin
cp bin/spk bundle/bin/spk
cp bin/minibox bundle/bin/minibox
cp bin/sandstorm-supervisor bundle/bin/sandstorm-supervisor
cp bin/sandstorm-http-bridge bundle/bin/sandstorm-http-bridge
cp bin/run-bundle bundle/sandstorm
cp $METEOR_TOOLS/bin/node bundle/bin
cp $METEOR_TOOLS/mongodb/bin/{mongo,mongod} bundle/bin
cp $(which zip unzip xz) bundle/bin

# Binaries copied from Meteor aren't writable by default.
chmod u+w bundle/bin/*

# Copy over capnp schemas.
mkdir -p bundle/usr/include/{capnp,sandstorm}
test -e /usr/include/capnp/c++.capnp && cp /usr/include/capnp/*.capnp bundle/usr/include/capnp
test -e /usr/local/include/capnp/c++.capnp && cp /usr/local/include/capnp/*.capnp bundle/usr/include/capnp
cp src/sandstorm/*.capnp bundle/usr/include/sandstorm

# Copy over all necessary shared libraries.
(ldd bundle/bin/* $(find bundle -name '*.node') || true) | grep -o '[[:space:]]/[^ ]*' | copyDeps

# Determine dependencies needed to run getaddrinfo() and copy them over.  glibc loads the
# DNS library dynamically, so `ldd` alone won't tell us this.  Also we want to find out
# what config files are needed from /etc, though we don't copy them over until runtime.
cat > tmp/dnstest.c << '__EOF__'
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <stdlib.h>

int main() {
  struct addrinfo* result;
  getaddrinfo("example.com", "http", NULL, &result);
  return 0;
}
__EOF__

gcc tmp/dnstest.c -o tmp/dnstest
strace tmp/dnstest 2>&1 | grep -o '"/[^"]*"' | tr -d '"' | copyDeps

# Dedup the etc.list and copy over.  Don't copy the ld.so.x files, though.
cat tmp/etc.list | grep -v '/ld[.]so[.]' | sort | uniq > bundle/etc.list

# Make mount points.
mkdir -p bundle/{dev,proc,tmp,etc,var}
touch bundle/dev/{null,zero,random,urandom,fuse}

# Mongo wants these localization files.
mkdir -p bundle/usr/lib
cp -r /usr/lib/locale bundle/usr/lib
mkdir -p bundle/usr/share/locale
cp /usr/share/locale/locale.alias bundle/usr/share/locale

# Make bundle smaller by stripping stuff.
strip bundle/sandstorm bundle/bin/*
find bundle -name '*.so' | xargs strip

git rev-parse HEAD > bundle/git-revision
echo "$USER@$HOSTNAME $(date)" > bundle/buildstamp

cat > bundle/README.md << '__EOF__'
# Sandstorm Bundle

See: http://sandstorm.io

This is a self-contained, batteries-included Sandstorm server.  This should
work on any recent Linux kernel (tested on 3.10, but some earlier versions
might work too).  The rest of your filesystem is not touched and may as well
be empty; everything will run in a chroot.

This bundle is intended to be installed using the Sandstorm installer or
updater. To install Sandstorm, please run:

    curl https://install.sandstorm.io | bash

If you have already installed Sandstorm, you can update your installation to
this version by running:

    service sandstorm update <filename>.tar.xz
__EOF__