#!/bin/sh
#
# pbuilder hook script: choose optional compiler rather than default one
#  
# Sometimes we want to choose other compiler than default, because of improving
# code to conform to standard, check compiler quality or so. This script will
# ease it. Try enable hook script and set "CHOOSE_COMPILER" variables as clang,
# gcc-*, or other compilers (note: however, now only clang and gcc can works
# well and others fails to build).
#
# i.e.)
#  $ sudo CHOOSE_COMPILER="clang" pbuilder --build foobar_1.0-1.dsc
#  $ sudo CHOOSE_COMPILER="gcc-4.6" pbuilder --build foobar_1.0-1.dsc
#

set -e

# check whether we are asked to change the compiler.
case "$CHOOSE_COMPILER" in
	clang)
	  newcc=/usr/bin/"$CHOOSE_COMPILER"
	  newcxx=/usr/bin/"$CHOOSE_COMPILER"++
  	;;
	gcc-*)
          use_gcc_version=`echo $CHOOSE_COMPILER | sed -e s/gcc-//`
	  gxx_package=g++-"$use_gcc_version"
	  newcc=/usr/bin/"$CHOOSE_COMPILER"
	  newcxx=/usr/bin/g++-"$use_gcc_version"
	;;
	tcc)
	  newcc=/usr/bin/"$CHOOSE_COMPILER"
	  newcxx=/bin/false
	  not_gcc_compat=1
	;;
	pcc)
	  newcc=/usr/bin/"$CHOOSE_COMPILER"
	  newcxx=/bin/false
	  not_gcc_compat=1
	;;
	asn1c)
	  newcc=/usr/bin/"$CHOOSE_COMPILER"
	  newcxx=/bin/false
	  not_gcc_compat=1
	;;
	*)
	  exit 0
	;;
esac

for compiler in $CHOOSE_COMPILER $gxx_package
do
    apt-get -y install "$compiler" || {
	echo >&2 "E: Installing the compiler "$compiler" failed"
	exit 1
    }
done

test -x /usr/bin/"$CHOOSE_COMPILER" || {
	echo >&2 "E: Package "$CHOOSE_COMPILER" does not contain compiler driver?"
	exit 1
}


ln -sf "$newcc" /usr/bin/cc
ln -sf "$newcxx" /usr/bin/c++

if [ x"$not_gcc_compat" = x ]; then
	(cd /usr/bin; ln -sf "$newcc" gcc; ln -sf "$newcxx" g++)
else
	rm -f /usr/bin/gcc /usr/bin/g++
fi

exit 0