#! /bin/bash

# qemu 
# Source: https://wiki.qemu-project.org/download/qemu-7.0.0.tar.xz 
#
# $BUILD = Directory to temporarily install
# $PKGS  = Directory to store built packages
#
# DEPS
# Required:     glib 
# Recommended:  alsa-lib curl gnutls libjpeg-turbo libpng libseccomp
# Recommended:  libusb libxml2 lzo vte3 libaio snappy libnfs libcap-ng
# Recommended:  sdl2 libgcrypt nettle mesa 
# Optional:     libssh liburing virglrenderer vde2 bridge-utils

# check to see if your processor supports Virtualization Technology (VT):
egrep '^flags.*(vmx|svm)' /proc/cpuinfo
# if there is any output, you have VT technology (vmx for Intel processors 
# and svm for AMD processors). You then need to go into your system BIOS 
# and ensure it is enabled. After enabling, reboot back to your MLFS instance. 

# Kernel Configuration 
# Enable the following options in the kernel configuration:
#
# [*] Virtualization:  --->                                            [CONFIG_VIRTUALIZATION]
#  <*/M>   Kernel-based Virtual Machine (KVM) support [CONFIG_KVM]
#  <*/M>     KVM for Intel (and compatible) processors support         [CONFIG_KVM_INTEL]
#  <*/M>     KVM for AMD processors support                            [CONFIG_KVM_AMD]
#
# To use the “bridge” network device, as explained below, check that 
# bridge-utils is installed and the following options in the kernel 
# configuration are enabled: 
#
# [*] Networking support  --->                         [CONFIG_NET]
#  Networking options  --->
#     <*/M> 802.1d Ethernet Bridging                   [CONFIG_BRIDGE]
#      Device Drivers  --->
#   [*] Network device support  --->                   [CONFIG_NETDEVICES]
#     <*/M>    Universal TUN/TAP device driver support [CONFIG_TUN]
#

# Check if there is kvm group in /etc/group. If not, add as root:
cat >> /etc/group << EOF
kvm:x:61:
EOF

# Add any users that might use the KVM device to that group: 
sudo -S usermod -a -G kvm ${username}

# As root, Add an Udev rule so that the KVM device gets correct permissions: 
cat > /lib/udev/rules.d/65-kvm.rules << "EOF"
KERNEL=="kvm", GROUP="kvm", MODE="0660"
EOF

# Apply patches from Alpine Linux
patch -Np1 -i ../patches/qemu-alpine/0006-linux-user-signal.c-define-__SIGRTMIN-MAX-for-non-GN.patch 
patch -Np1 -i ../patches/qemu-alpine/CVE-2021-20255.patch 
patch -Np1 -i ../patches/qemu-alpine/MAP_SYNC-fix.patch
patch -Np1 -i ../patches/qemu-alpine/guest-agent-shutdown.patch
patch -Np1 -i ../patches/qemu-alpine/mips-softfloat.patch 
patch -Np1 -i ../patches/qemu-alpine/musl-initialise-msghdr.patch
patch -Np1 -i ../patches/qemu-alpine/xattr_size_max.patch

# Create build directories
mkdir -pv build 
# mkdir -pv build-static

# Set the configure options
export  CMM_ARGS="--prefix=/usr "
export CMM_ARGS+="--localstatedir=/var "
export CMM_ARGS+="--sysconfdir=/etc "
export CMM_ARGS+="--libexecdir=/usr/lib/qemu "
export CMM_ARGS+="--python=/usr/bin/python3 "
export CMM_ARGS+="--disable-glusterfs "
export CMM_ARGS+="--disable-debug-info "
export CMM_ARGS+="--disable-bsd-user "
export CMM_ARGS+="--disable-werror "
export CMM_ARGS+="--disable-xen "
export CMM_ARGS+="--enable-kvm "
export CMM_ARGS+="--enable-seccomp "

#export  STTC_ARGS="--enable-linux-user "
#export STTC_ARGS+="--disable-system "
#export STTC_ARGS+="--static "
#export STTC_ARGS+="--disable-docs "
#export STTC_ARGS+="--disable-sdl "
#export STTC_ARGS+="--disable-gtk "
#export STTC_ARGS+="--disable-spice "
#export STTC_ARGS+="--disable-guest-agent "
#export STTC_ARGS+="--disable-guest-agent-msi "
#export STTC_ARGS+="--disable-curses "
#export STTC_ARGS+="--disable-curl "
#export STTC_ARGS+="--disable-gnutls "
#export STTC_ARGS+="--disable-gcrypt "
#export STTC_ARGS+="--disable-nettle "
#export STTC_ARGS+="--disable-cap-ng "
#export STTC_ARGS+="--disable-brlapi "
#export STTC_ARGS+="--disable-mpath "
#export STTC_ARGS+="--disable-libnfs "
#export STTC_ARGS+="--disable-numa "
#export STTC_ARGS+="--disable-capstone "

export  DYN_ARGS="--disable-linux-user "
export DYN_ARGS+="--audio-drv-list=oss,alsa,sdl,pa "
export DYN_ARGS+="--enable-cap-ng " # if libcap-ng is installed
export DYN_ARGS+="--enable-curl "
export DYN_ARGS+="--enable-curses "
export DYN_ARGS+="--enable-gtk "
export DYN_ARGS+="--enable-guest-agent "
export DYN_ARGS+="--enable-libnfs "
export DYN_ARGS+="--enable-libssh "
export DYN_ARGS+="--enable-linux-aio " 
export DYN_ARGS+="--enable-lzo "
export DYN_ARGS+="--enable-modules "
export DYN_ARGS+="--enable-numa " # if numba is installed
export DYN_ARGS+="--enable-pie "
export DYN_ARGS+="--enable-sdl "
export DYN_ARGS+="--enable-snappy " 
export DYN_ARGS+="--enable-spice " # if spice is installed
export DYN_ARGS+="--enable-tpm "
export DYN_ARGS+="--enable-usb-redir " # if libusbredirparser is installed
export DYN_ARGS+="--enable-vde " # if vde2 is installed
export DYN_ARGS+="--enable-vhost-net "
export DYN_ARGS+="--enable-virglrenderer " # if virglrender is installed
export DYN_ARGS+="--enable-virtfs "
export DYN_ARGS+="--enable-vnc "
export DYN_ARGS+="--enable-vnc-jpeg "
export DYN_ARGS+="--enable-vnc-png "
export DYN_ARGS+="--enable-zstd "

# To emulate only arm, arm64, i686, amd64:
#export $BUILD_TARGETS='--target-list="i386-softmmu x86_64-softmmu aarch64-softmmu arm-softmmu" '

# Compile

# Static compile fails to configure... complains about wrong glib
#cd build-static
#../configure $CMM_ARGS $STTC_ARGS 
#make ARFLAGS="rc"
#cd ..

cd build
../configure $CMM_ARGS $DYN_ARGS  --tls-priority=@QEMU,SYSTEM
make ARFLAGS="rc"
cd ..

# Install

#cd build-static
#sudo -S make DESTDIR=$BUILD install
#cd ..

cd build
sudo -S make DESTDIR=$BUILD install && \
udo -S install -Dm640 -g kvm ../../files/qemu-alpine/bridge.conf $BUILD/etc/qemu/bridge.conf && \
sudo -S  chmod -v 04710 $BUILD/usr/lib/qemu/qemu-bridge-helper && \
sudo -S  chgrp -v kvm   $BUILD/usr/lib/qemu/qemu-bridge-helper && \

cd $BUILD && sudo -S mkdir -v ${BUILD}/install &&
cat > /tmp/slack-desc << "EOF"
# HOW TO EDIT THIS FILE:
# The "handy ruler" below makes it easier to edit a package description.  Line
# up the first '|' above the ':' following the base package name, and the '|'
# on the right side marks the last column you can put a character in.  You must
# make exactly 11 lines for the formatting to be correct.  It's also
# customary to leave one space after the ':' except on otherwise blank lines.

    |-----handy-ruler------------------------------------------------------|
qemu: qemu
qemu:
qemu: A generic machine emulator and virtualizer.
qemu:
qemu: https://qemu.org/
qemu:
EOF
sudo -S mv -v /tmp/slack-desc install/ &&
sudo -S makepkg -l y -c n $PKGS/qemu-7.0.0-$(uname -m)-mlfs.txz &&
sudo -S rm -rf ${BUILD}/*