1#!/bin/sh
2#
3# Simple wrapper for debootstrap, run in the docker build context
4#
5FAKEROOT=$(which fakeroot 2> /dev/null)
6# debootstrap < 1.0.67 generates empty sources.list, see Debian#732255
7MIN_DEBOOTSTRAP_VERSION=1.0.67
8
9exit_and_skip()
10{
11    exit 3
12}
13
14#
15# fakeroot is needed to run the bootstrap stage
16#
17if [ -z $FAKEROOT ]; then
18    echo "Please install fakeroot to enable bootstraping" >&2
19    exit_and_skip
20
21fi
22
23if [ -z "${DEB_ARCH}" ]; then
24    echo "Please set DEB_ARCH to choose an architecture (e.g. armhf)" >&2
25    exit_and_skip
26
27fi
28
29if [ -z "${DEB_TYPE}" ]; then
30    echo "Please set DEB_TYPE to a Debian archive name (e.g. testing)" >&2
31    exit_and_skip
32
33fi
34
35# The following allow finer grain control over the defaults
36if [ -z "${DEB_VARIANT}" ]; then
37    DEB_VARIANT=buildd
38fi
39
40if [ -z "${DEB_URL}" ]; then
41    DEB_URL="http://httpredir.debian.org/debian"
42fi
43
44# We check in order for
45#
46#  - DEBOOTSTRAP_DIR pointing at a development checkout
47#  - PATH for the debootstrap script (installed)
48#
49# If neither option works then we checkout debootstrap from its
50# upstream SCM and run it from there.
51#
52
53if [ -z $DEBOOTSTRAP_DIR ]; then
54    NEED_DEBOOTSTRAP=false
55    DEBOOTSTRAP=$(which debootstrap 2> /dev/null)
56    if [ -z $DEBOOTSTRAP ]; then
57        echo "No debootstrap installed, attempting to install from SCM"
58        NEED_DEBOOTSTRAP=true
59    else
60        INSTALLED_VERSION=$(${DEBOOTSTRAP} --version | sed 's/debootstrap \([0-9\.]*\)[^0-9\.]*.*/\1/')
61        if ! (echo "${MIN_DEBOOTSTRAP_VERSION}" ; echo "${INSTALLED_VERSION}") \
62                | sort -t . -n -k 1,1 -k 2,2 -k 3,3 -C ; then
63            echo "debootstrap too old, attempting to install from SCM"
64            NEED_DEBOOTSTRAP=true
65        fi
66    fi
67    if $NEED_DEBOOTSTRAP; then
68        DEBOOTSTRAP_SOURCE=https://salsa.debian.org/installer-team/debootstrap.git
69        git clone ${DEBOOTSTRAP_SOURCE} ./debootstrap.git
70        export DEBOOTSTRAP_DIR=./debootstrap.git
71        DEBOOTSTRAP=./debootstrap.git/debootstrap
72        (cd "${DEBOOTSTRAP_DIR}" && "${FAKEROOT}" make )
73    fi
74else
75    DEBOOTSTRAP=${DEBOOTSTRAP_DIR}/debootstrap
76    if [ ! -f $DEBOOTSTRAP ]; then
77        echo "Couldn't find script at ${DEBOOTSTRAP}" >&2
78        exit_and_skip
79    fi
80fi
81
82#
83# Finally check to see if any qemu's are installed
84#
85BINFMT_DIR=/proc/sys/fs/binfmt_misc
86if [ ! -e $BINFMT_DIR ]; then
87   echo "binfmt_misc needs enabling for a QEMU bootstrap to work" >&2
88   exit_and_skip
89else
90    # DEB_ARCH and QEMU arch names are not totally aligned
91    case "${DEB_ARCH}" in
92        amd64)
93            QEMU=qemu-i386
94            ;;
95        armel|armhf)
96            QEMU=qemu-arm
97            ;;
98        arm64)
99            QEMU=qemu-aarch64
100            ;;
101        powerpc)
102            QEMU=qemu-ppc
103            ;;
104        ppc64el)
105            QEMU=qemu-ppc64le
106            ;;
107        s390)
108            QEMU=qemu-s390x
109            ;;
110        *)
111            QEMU=qemu-${DEB_ARCH}
112        ;;
113    esac
114    if [ ! -e "${BINFMT_DIR}/$QEMU" ]; then
115        echo "No binfmt_misc rule to run $QEMU, can't bootstrap" >&2
116        exit_and_skip
117    fi
118fi
119
120echo "Building a rootfs using ${FAKEROOT} and ${DEBOOTSTRAP} ${DEB_ARCH}/${DEB_TYPE}"
121
122${FAKEROOT} ${DEBOOTSTRAP} --variant=$DEB_VARIANT --foreign --arch=$DEB_ARCH $DEB_TYPE . $DEB_URL || exit 1
123exit 0
124