modular_config.sh

#!/bin/bash

modules=""
ncpu=$(($(nproc --all) - 2))

while getopts "m:c:" opt; do
    case $opt in
        m) modules="$OPTARG";;
        c) ncpu="$OPTARG";;
    esac
done

shift $((OPTIND-1))

# Ensure ncpu is at least 1
if [[ $ncpu -lt 1 ]]; then
    ncpu=1
fi

# Determine the package manager
pkg_manager=""
if command -v apt &>/dev/null; then
    pkg_manager="apt"
elif command -v yum &>/dev/null; then
    pkg_manager="yum"
elif command -v yay &>/dev/null; then
    pkg_manager="yay"  # Assuming yay is used for the Arch User Repository (AUR)
elif command -v pacman &>/dev/null; then
    pkg_manager="pacman"  # Assuming pacman is used for the Arch User Repository (AUR)
else
    echo "Unsupported package manager. Please install required packages manually and re-run the script."
    exit 1
fi

# Install selected modules or install everything if no modules provided
if [ -n "$modules" ]; then
    IFS=',' read -ra module_list <<< "$modules"
    for module in "${module_list[@]}"; do
        case $module in
            "binutils")
                install_binutils=true
                ;;
            "gcc")
                install_gcc=true
                ;;
            "nasm")
                install_nasm=true
                ;;
            "grub")
                install_grub=true
                ;;
            "xorriso")
                install_xorriso=true
                ;;
            "packages")
                install_packages=true
                ;;
            *)
                echo "Unknown module: $module"
                ;;
        esac
    done
else
    # Install everything by default
    install_binutils=true
    install_gcc=true
    install_nasm=true
    install_grub=true
    install_xorriso=true
    install_packages=true
fi

export cc_prefix="$HOME/opt/cross"
export cc_target=i686-elf
export PATH="$cc_prefix/bin:$PATH"

if [ "$install_packages" = true]; then
    case $pkg_manager in
        "apt")
            sudo apt update
            sudo apt install -y build-essential bison flex libgmp3-dev libmpc-dev libmpfr-dev texinfo libisl-dev
            ;;
        "yum")
            wget https://nasm.us/nasm.repo -O /etc/yum.repos.d/nasm.repo
            sudo yum -y install gcc make bison flex gmp-devel mpfr-devel libmpc-devel texinfo isl-devel
            ;;
        "yay" | "pacman")
            yay -S --noconfirm base-devel gmp mpfr libmpc texinfo isl
            ;;
    esac
fi

# Install selected or all modules
if [ "$install_binutils" = true ]; then
    mkdir -p $HOME/src
    cd $HOME/src

    wget https://ftp.gnu.org/gnu/binutils/binutils-2.34.tar.xz
    tar -xf binutils-2.34.tar.xz

    mkdir build-binutils
    cd build-binutils
    ../binutils-2.34/configure --target=$cc_target --prefix="$cc_prefix" --with-sysroot --disable-nls --disable-werror
    make -j$ncpu
    make install -j$ncpu
fi

if [ "$install_gcc" = true ]; then
    mkdir -p $HOME/src
    cd $HOME/src

    wget https://ftp.gnu.org/gnu/gcc/gcc-9.4.0/gcc-9.4.0.tar.gz
    tar -xf gcc-9.4.0.tar.gz

    mkdir build-gcc
    cd build-gcc
    ../gcc-9.4.0/configure --target=$cc_target --prefix="$cc_prefix" --disable-nls --enable-languages=c --without-headers
    make all-gcc -j$ncpu
    make all-target-libgcc -j$ncpu
    make install-gcc -j$ncpu
    make install-target-libgcc -j$ncpu
fi

if [ "$install_nasm" = true ]; then
    if command -v nasm &>/dev/null; then
        echo "nasm already installed"
    else
        echo "nasm not installed. Installing..."

        cd $HOME/src
        wget https://www.nasm.us/pub/nasm/releasebuilds/2.16.01/nasm-2.16.01.tar.gz
        tar xf nasm-2.16.01.tar.gz
        cd nasm-2.16.01
        ./configure
        make install -j$ncpu
    fi
fi

if [ "$install_grub" = true ]; then
    if command -v grub-mkrescue &>/dev/null; then
        echo "grub-mkrescue already installed"
    else
        echo "grub-mkrescue not installed. Installing..."

        cd $HOME/src
        wget ftp://ftp.gnu.org/gnu/grub/grub-2.06.tar.gz
        tar xf grub-2.06.tar.gz
        cd grub-2.06
        ./configure
        sudo make install -j$ncpu
    fi
fi

if [ "$install_xorriso" = true ]; then
    if command -v xorriso &>/dev/null; then
        echo "xorriso already installed"
    else
        echo "xorriso not installed. Installing..."

        cd $HOME/src
        wget https://www.gnu.org/software/xorriso/xorriso-1.5.6.tar.gz
        tar xf xorriso-1.5.6.tar.gz
        cd xorriso-1.5.6
        ./configure
        make install -j$ncpu
    fi
fi

# Set up environment variables for Bash shell
echo "export PATH=$HOME/opt/cross/bin:\$PATH" >> ~/.bashrc
echo "export cc_prefix=$HOME/opt/cross" >> ~/.bashrc
echo "export cc_target=i686-elf" >> ~/.bashrc

# Set up environment variables for Fish shell (if Fish is installed)
if command -v fish &>/dev/null; then
    fish -c "set -U fish_user_paths $HOME/opt/cross/bin $fish_user_paths"
    fish -c "set -Ux cc_prefix $HOME/opt/cross"
    fish -c "set -Ux cc_target i686-elf"
fi

echo "Cross-compiler installation complete. Please restart your shell or run 'source ~/.bashrc' (or equivalent for your shell) to update your PATH."