From bf2c38c3ff15bceecbf57530801a76f74b7cff90 Mon Sep 17 00:00:00 2001
From: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Date: Thu, 19 May 2022 03:41:42 +0530
Subject: [PATCH] Debian custom kernel build script

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
---
 debian_custom_kernel_build.sh | 97 +++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)
 create mode 100755 debian_custom_kernel_build.sh

diff --git a/debian_custom_kernel_build.sh b/debian_custom_kernel_build.sh
new file mode 100755
index 0000000..edda65b
--- /dev/null
+++ b/debian_custom_kernel_build.sh
@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+
+# Author : Bhaskar Chowdhury
+# LICENSE : GPL-2
+# For kernel download helper script: https://git.kernel.org/pub/scm/linux/kernel/git/mricon/korg-helpers.git/tree/get-verified-tarball
+
+
+get_make=$(command -v make)
+get_elapsed_time="/usr/bin/time -f"
+untar_it="tar -xJvf"
+existing_config_file="/boot/config-$(uname -r)"
+build_dir=$HOME/latest_kernel_build
+get_it=$(command -v secure_kernel_tarball)
+NOTIFY=$(command -v notify-send)
+
+clear
+cat << "EOF"
+  _  __                    _
+ | |/ /___ _ __ _ __   ___| |
+ | ' // _ \ '__| '_ \ / _ \ |
+ | . \  __/ |  | | | |  __/ |
+ |_|\_\___|_|  |_| |_|\___|_|_ _       _   _
+  / ___|___  _ __ ___  _ __ (_) | __ _| |_(_) ___  _ __
+ | |   / _ \| '_ ` _ \| '_ \| | |/ _` | __| |/ _ \| '_ \
+ | |__| (_) | | | | | | |_) | | | (_| | |_| | (_) | | | |
+  \____\___/|_| |_| |_| .__/|_|_|\__,_|\__|_|\___/|_| |_|
+                      |_|
+EOF
+
+if [[ ! -d $build_dir ]];then
+	mkdir -p $build_dir
+fi
+
+cd $build_dir
+
+debian_kernel_build() {
+
+#Download the kernel and get into the download dir
+which_kernel
+
+eval ${get_it} ${kernel}
+
+#Untar it
+$untar_it linux-$kernel.tar.xz
+
+#Get into the kernel direcory
+cd linux-$kernel
+
+#Clean the dir
+$get_make clean && $get_make mrproper
+
+#Copying existing/running kernel config
+cp $existing_config_file .config
+
+#Disable this option to shorten the compile time
+scripts/config --disable DEBUG_KERNEL
+grep DEBUG_KERNEL .config
+
+#Disable this option to shorten the compile time
+scripts/config --disable DEBUG_INFO
+grep DEBUG_INFO .config
+
+#This is needed ,otherwise it won't allow you to build
+scripts/config --disable system_trusted_keys
+grep CONFIG_SYSTEM_TRUSTED_KEYS .config
+
+#Make sure the flags symbols are set correctly with an updated value
+$get_make  ARCH=x86_64 olddefconfig
+
+# Now build it
+$get_elapsed_time "\n\n\tTime Elapsed: %E\n\n" $get_make ARCH=x86_64 V=1 -j$(getconf _NPROCESSORS_ONLN) deb-pkg
+
+
+printf "\n\n\n Install the generated packages aka kernel,headers,modules et al\n\n\n"
+
+cd ..
+
+dpkg -i *.deb
+}
+
+which_kernel() {
+printf "\n\n Which kernel would be your base? Stable or Mainline or Longterm? [S/M/L]: %s"
+read response
+
+if [[ $response == "S" ]];then
+#Get the stable kernel from kernel.org
+kernel=$(curl -s https://www.kernel.org/ | grep -A1 'stable:' | grep -oP '(?<=strong>).*(?=</strong.*)' | grep 5.17)
+elif [[ $response == "M" ]];then
+#Get the mainline kernel from kernel.org
+kernel=$(curl -s https://www.kernel.org/ | grep -A1 'mainline:' | grep -oP '(?<=strong>).*(?=</strong.*)')
+elif [[ $response == "L" ]];then
+#Get the longterm kernel from kernel.org
+kernel=$(curl -s https://www.kernel.org/ | grep -A1 'longterm:' | grep -oP '(?<=strong>).*(?=</strong.*)')
+fi
+}
+
+debian_kernel_build