#!/bin/sh

# Copyright 2018, 2020, 2021  Patrick J. Volkerding, Sebeka, Minnesota, USA
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# Modified by Didier Spaier didieratslintdotfr for Slint.
# zstd compressor everywhere but for the modules
# two packages are built:
# "kernel" includes the kernel (generic in Slackware parlance), modules and sanitized headers.
# "source"


# CONFIG_PREEMPT_DEFAULT_MODE= voluntary
cd "$(dirname "$0")" || exit 1
CWD="$(pwd)"
VERSION=6.6.7
KERNEL_ARCH=x86
ARCH=$(uname -m)
HEADERS_ARCH=x86
BUILD=1slint
NUMJOBS="-j$(($(nproc)+1))"
echo "NUMJOBS=$NUMJOBS"
sleep 3
TMP="$CWD"
PKGSOURCE="$TMP/PKGSOURCE"
PKGKERNEL="$TMP/PKGKERNEL"
rm -rf "$PKGSOURCE" "$PKGKERNEL"
mkdir -p "$PKGSOURCE"/usr/src \
"$PKGSOURCE"/install \
"$PKGKERNEL"/boot \
"$PKGKERNEL"/install \
"$PKGKERNEL"/lib/modules \
"$PKGKERNEL"/usr/include

echo "Using kernel config: $CWD/kernel-configs/config-$VERSION"
echo "Untarring $CWD/linux-${VERSION}.tar.?z in $PKGSOURCE/usr/src..."
cd "$PKGSOURCE"/usr/src || exit 1
tar xf "$CWD"/linux-"${VERSION}".tar.?z || exit 1
echo "Making /usr/src/linux symlink..." 
ln -sf linux-"$VERSION" linux
cd linux-"$VERSION" || exit 1
cp -a "$CWD"/kernel-configs/config-"$VERSION" .config
echo "Fixing permissions/ownership..."
chown -R root:root .
cd "$PKGSOURCE"/usr/src/linux-"$VERSION" || exit 1
echo "Making oldconfig..."
make oldconfig
echo "Building kernel and modules..."
ZSTD_CLEVEL=19 make "$NUMJOBS" || make || exit 1
cp -a --verbose System.map "$PKGKERNEL"/boot/System.map-"${VERSION}"
cp -a --verbose .config "$PKGKERNEL/boot/config-${VERSION}$CONFIG_SUFFIX"
cp -a --verbose arch/${KERNEL_ARCH}/boot/bzImage "$PKGKERNEL"/boot/vmlinuz-"$VERSION"
make "$NUMJOBS" modules || exit 1
make INSTALL_MOD_PATH="$PKGKERNEL" modules_install || exit 1
echo "Generating headers from the Linux kernel source tree :"
make headers_install ARCH="$HEADERS_ARCH" INSTALL_HDR_PATH="$PKGKERNEL"/usr

echo "Cleaning up..."
make clean
# Make sure header files aren't missing...
make prepare
# Don't package the kernel in the sources:
find . -name "*Image" -exec rm "{}" \+
# No need for these:
rm -f .config.old .version
find . -name "*.cmd" -exec rm -f "{}" \+ 
rm .*.d
# Still some dotfiles laying around... probably fine though
# Use the version number found in the Makefile in the package name.

cd "$PKGKERNEL"/lib/modules/"$VERSION" || exit 1
for symlink in build source ; do
   rm -f $symlink
   ln -s /usr/src/linux-"$VERSION" $symlink
done
cd "$PKGSOURCE"/usr/src/linux-"$VERSION" || exit 1
depmod -b "$PKGKERNEL" -a "$VERSION"

echo "Generating headers from the Linux kernel source tree in $KERNEL_SOURCE:"
make headers_install ARCH="$HEADERS_ARCH" INSTALL_HDR_PATH="$PKGKERNEL"/usr
cd "$PKGKERNEL"/usr/include || exit 1
# You won't want these files. The ones in libdrm work better.
rm -rf drm
# This next part seems pretty much cosmetic, but since we've been doing this
# for a long time (and others also do), we'll stick with it:
mv asm asm-"$HEADERS_ARCH"
ln -sf asm-"$HEADERS_ARCH" asm
# Remove unneeded dotfiles:
find . -name ".??*" -exec rm -f {} \+

PACKAGE_VERSION="$(grep "^VERSION = " Makefile | rev | cut -f 1 -d ' ' | rev).$(grep "^PATCHLEVEL = " Makefile | rev | cut -f 1 -d ' ' | rev).$(grep "^SUBLEVEL = " Makefile | rev | cut -f 1 -d ' ' | rev)$(grep "^EXTRAVERSION = " Makefile | rev | cut -f 1 -d ' ' | rev)"
cat "$CWD"/slack-desc/slack-desc.kernel-source > "$PKGSOURCE"/install/slack-desc
cd "$PKGSOURCE" || exit 1
/sbin/makepkg -l y -c n "$TMP"/kernel-source-"$(echo "$VERSION" | tr - _)"-noarch-"$BUILD".txz


cat "$CWD"/slack-desc/slack-desc.kernel > "$PKGKERNEL"/install/slack-desc
cd "$PKGKERNEL" || exit 1
/sbin/makepkg -l y -c n "$TMP"/kernel-"$(echo "$VERSION" | tr - _)"-"$ARCH"-$BUILD.txz
echo "All done."