Build i386 binary

Fixes #30

.travis.yml

@@ -8,6 +8,7 @@ env:
     - CC=gcc ARCH_SUFFIX=amd64 ARCH_NATIVE=1 MINIMAL=
     - CC=arm-linux-gnueabihf-gcc ARCH_SUFFIX=armhf ARCH_NATIVE= MINIMAL=
     - CC=aarch64-linux-gnu-gcc ARCH_SUFFIX=arm64 ARCH_NATIVE= MINIMAL=
+    - CFLAGS="-m32" ARCH_SUFFIX=i386 ARCH_NATIVE=1
     - CC=gcc ARCH_SUFFIX=amd64 ARCH_NATIVE=1 MINIMAL=1
   global:
     - SIGN_BINARIES=1

Dockerfile

@@ -1,5 +1,7 @@
 FROM ubuntu:trusty
 
+ARG ARCH_SUFFIX
+
 COPY ci/install_deps.sh /install_deps.sh
 RUN /install_deps.sh
 

ci/install_deps.sh

@@ -4,11 +4,25 @@ set -o nounset
 
 apt-get update
 
-apt-get install --no-install-recommends --yes \
+DEPS=(
   build-essential git gdb valgrind cmake rpm \
   python-dev libcap-dev python-pip python-virtualenv \
-  hardening-includes gnupg \
-  gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu libc6-dev-arm64-cross \
-  gcc-arm-linux-gnueabihf binutils-arm-linux-gnueabi libc6-dev-armhf-cross
+  hardening-includes gnupg
+)
+
+if [[ "$ARCH_SUFFIX" = "amd64" ]]; then
+  true
+elif [[ "$ARCH_SUFFIX" = "armhf" ]]; then
+  DEPS+=(gcc-arm-linux-gnueabihf binutils-arm-linux-gnueabi libc6-dev-armhf-cross)
+elif [[ "$ARCH_SUFFIX" = "arm64" ]]; then
+  DEPS+=(gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu libc6-dev-arm64-cross)
+elif [[ "$ARCH_SUFFIX" = "i386" ]]; then
+  DEPS+=(libc6-dev-i386  gcc-multilib)
+else
+  echo "Unknown ARCH_SUFFIX=${ARCH_SUFFIX}"
+  exit 1
+fi
+
+apt-get install --no-install-recommends --yes "${DEPS[@]}"
 
 rm -rf /var/lib/apt/lists/*

ddist.sh

@@ -2,17 +2,24 @@
 set -o errexit
 set -o nounset
 
+if [[ "$#" != 1 ]]; then
+  echo "Usage: $0 ARCH_SUFFIX"
+  exit 1
+fi
+
+suffix="$1"
+
 REL_HERE=$(dirname "${BASH_SOURCE}")
 HERE=$(cd "${REL_HERE}"; pwd)
 
-IMG="tini"
+IMG="tini-build-${suffix}"
 SRC="/tini"
 
 # Cleanup the build dir
 rm -f "${HERE}/dist"/*
 
 # Create the build image
-docker build -t "${IMG}" .
+docker build --build-arg "ARCH_SUFFIX=${suffix}" -t "${IMG}" .
 
 # Run test without subreaper support, don't copy build files here
 docker run -it --rm \
@@ -22,7 +29,8 @@ docker run -it --rm \
   -e FORCE_SUBREAPER="${FORCE_SUBREAPER:="1"}" \
   -e GPG_PASSPHRASE="${GPG_PASSPHRASE:=}" \
   -e CC="${CC:=gcc}" \
+  -e CFLAGS="${CFLAGS-}" \
   -e ARCH_NATIVE="${ARCH_NATIVE-1}" \
-  -e ARCH_SUFFIX="${ARCH_SUFFIX-}" \
+  -e ARCH_SUFFIX="${suffix}" \
   -e MINIMAL="${MINIMAL-}" \
   "${IMG}" "${SRC}/ci/run_build.sh"