#!/bin/sh -e

for patch in patch/*.patch; do
    patch -p1 < "$patch"
done

# Remove forced gcc/g++ usage so builds work on gcc-less systems.
sed -e "s#= g[c+][c+]#= ${CC:=cc}#g" \
    -e "s#\(\$(CROSS_COMPILE)\)gcc#\1${CC}#g" Makefile > _
mv -f _ Makefile

case $("$CC" --version) in *clang*)
    # Disable UB based optimizations which are optimized out by
    # clang and become null pointer dereferences(?).
    patch -p1 < patch-clang/fix-UB.patch

    # Ensure that busybox's build system is aware that 'cc' may point
    # to clang rather than GCC. This is the case in non-GCC systems.
    sed "s&\(\$(CC),\)clang&\1${CC}&g" Makefile.flags > _
    mv -f _ Makefile.flags
esac

# Build and install regular busybox.
# This excludes utilities which require 'suid' to function.
make CC="$CC" HOSTCC="$CC"
make CONFIG_PREFIX="$1/usr" install

# Rename the binary temporarily.
mv "$1/usr/bin/busybox" "$1/usr/bin/busybox-nosuid"

# Build and install suid busybox.
# This _only_ includes utlities which require 'suid' to function.
cp -f .config-suid .config
make CC="$CC" HOSTCC="$CC"
make CONFIG_PREFIX="$1/usr" install

# Aptly name the busybox binaries.
mv -f "$1/usr/bin/busybox"        "$1/usr/bin/busybox-suid"
mv -f "$1/usr/bin/busybox-nosuid" "$1/usr/bin/busybox"

# Install the non-suid symlinks.
"$1/usr/bin/busybox" --list | while read -r bin; do
    ln -s busybox "$1/usr/bin/$bin"
done

# Install the suid symlinks.
"$1/usr/bin/busybox-suid" --list | while read -r bin; do
    ln -s busybox-suid "$1/usr/bin/$bin"
done

# Set suid on busybox suid.
chmod u+s "$1/usr/bin/busybox-suid"

# The acpid command requires that this directory exist
# and does not automatically create it..
mkdir -p "$1/etc/acpid"

# Install runit services.
for s in acpid crond syslogd mdev ntpd; do
    mkdir -p "$1/etc/sv/$s"
    cp -f "$s.run" "$1/etc/sv/$s/run"
    ln -sf "/run/runit/supervise.$s" "$1/etc/sv/$s/supervise"
done

cp -f mdev.conf "$1/etc/mdev.conf"