#!/bin/bash
#
# This is the hook file executed by make-kpkg in the end of creation
# of the linux-image for a particular flavour. The major task it performs
# is the creation of the flavour-specific linux-headers package.
#
set -e

debhelper_pre() {
	dh_clean -k --package="$1"
	dh_installdirs --package="$1"
}

debhelper_post() {
	dh_installdocs --package="$1"
	dh_installchangelogs --package="$1"
	dh_compress --package="$1"
	dh_fixperms --package="$1"
	dh_strip --package="$1"
	dh_installdeb --package="$1"
	dh_gencontrol --package="$1"
	dh_md5sums --package="$1"
	dh_builddeb --package="$1"
}
# The version which ends up here is something like
# $(version)-$(abiname)-$(flavour) and debnum is just
# -$(abiname), so that the variables get the values:
# suffix=$(flavour)
# prefix=$(version)-$(abiname)
# prefix is then used to form a destination directory
# to link to. For cases with subarch we need to link
# to linux-headers-$(subarch)-$(version)-$(abiname),
# not just linux-headers-$(version)-$(abiname).
#
prefix="$DEBIAN_VERSION-$DEBIAN_ABINAME"
pkg="linux-headers-$prefix-$DEBIAN_FLAVOUR"
top="$PWD/debian/$pkg"
dir="$top/usr/src/$pkg"
#
# Here we need to find the kernel architecture which
# is appropriate for the current flavour. It is available
# in kernel-package as KERNEL_ARCH. Cleanest way is to get
# make-kpkg export it to this script. 
# 
# Currently we just use the fact that in the build directory
# the symlink include/asm must point to include/asm-${arch}
#
arch="$(readlink include/asm)"
arch="$(basename "${arch}")"
arch="${arch#asm-}"

debhelper_pre "$pkg"

#
# Stuff below is ugly as hell, but does the trick so I'm not
# touching it until we can invent something better.
#
mkdir -p "$dir/arch/$arch/kernel"
mkdir -p "$dir/include/linux"
cp -a .config "$dir"
echo "-$DEBIAN_ABINAME-$DEBIAN_FLAVOUR" > "$dir/.extraversion"

cp -a Module.symvers "$dir"

find . -mindepth 1 -maxdepth 1 \
	! -name debian -a ! -name Documentation -a ! -name include -a \
	! -name DEBIAN -a ! -name scripts -a ! -name arch -a ! -name '.*' -a \( \
	-name Makefile -o -type d \) \
	-printf "../linux-headers-$prefix/%f\n" |
	xargs ln -s --target-directory="$dir"

find "arch/$arch" -mindepth 1 -maxdepth 1 \( \
	-type d -a ! -name include -a ! -name kernel -o \
	-type f -a \( -name 'Makefile*' -o -name 'Kconfig*' \) \) \
	-printf "../../../linux-headers-$prefix/%p\n" |
	xargs ln -s --target-directory="$dir/arch/$arch"
if [ -d arch/$arch/include ]; then
	cp -a arch/$arch/include $dir/arch/$arch/include
fi
[ -f "arch/$arch/kernel/asm-offsets.s" ] && ln -f "arch/$arch/kernel/asm-offsets.s" "$dir/arch/$arch/kernel"
ln -s "../../../../linux-headers-$prefix/arch/$arch/kernel/Makefile" "$dir/arch/$arch/kernel"
find include -mindepth 1 -maxdepth 1 \
	! -name config -a ! -name linux -a ! -name 'asm-*' \
	-printf "../../linux-headers-$prefix/%p\n" |
	xargs ln -s --target-directory="$dir/include"
cp -a include/config "$dir/include"

ln -sf "asm-${arch}" "$dir/include/asm"
for i in generic $KERNEL_HEADER_DIRS; do
	mkdir "$dir/include/asm-$i"
	find "include/asm-$i" -mindepth 1 -maxdepth 1 \
		\( -type f -a ! -links 2 -o ! -type f \) \
		-printf "../../../linux-headers-$prefix/%p\n" |
		xargs --no-run-if-empty ln -s --target-directory="$dir/include/asm-$i"
	find "include/asm-$i" -mindepth 1 -maxdepth 1 \
		-type f -links 2 |
		xargs --no-run-if-empty ln -f --target-directory="$dir/include/asm-$i"
done

find include/linux -mindepth 1 -maxdepth 1 \
	! -name autoconf.h -a ! -name compile.h -a ! -name version.h \
	-printf "../../../linux-headers-$prefix/%p\n" |
	xargs ln -s --target-directory="$dir/include/linux"
cp -a include/linux/autoconf.h include/linux/compile.h \
	include/linux/version.h "$dir/include/linux"

mkdir -p "$top/lib/modules/$version"
ln -s "/usr/src/linux-headers-$version" "$top/lib/modules/$version/build"

# Populate the scripts directory. The strategy here is to specify what
# *not* to copy, to make things a little bit more robust. We first create
# a file with exclude patterns, then copy everything minus excluded files.
#
cat > scripts-exclude <<EXCLUDES
*.c
*.c_shipped
*.h
*.y
*.l
*.gperf
*POTFILES.in
*.gitignore
*lxdialog*
*package*
EXCLUDES
tar cfh - -X scripts-exclude scripts | (cd "$dir"; umask 000; tar xsf -)
rm -f script-exclude

debhelper_post "$pkg"

#
# Check whether we should force any modules to be available
# on the initrd.
#
cd "${IMAGE_TOP}/lib/modules/${version}"
modules='@initrd_modules@'
if [ -n "${modules}" ]; then
  mkdir initrd
  for i in ${modules}; do
    if [ -f "${i}" ]; then
      ln "${i}" initrd
    fi
  done
fi

#
# Clean up the build and source symlinks
#
if [ -L build ]; then
  rm -f build
fi
if [ -L source ]; then
  rm -f source
fi