halium-chroot

#!/bin/bash
#
# This script will:
# - mount rootfs.img, system.img and /data
# - enter an interactive shell in the chroot or execute
#   a given command
# - umount rootfs, system and /data
#
# Usage:
#
# To get an interactive shell in the chroot simply enter:
# ./halium-chroot
#
# To directly execute a non-interactive program run:
# ./halium-chroot my-program
#

mount_all()
{
	adb shell <<-SHELL
		mkdir -p /target
		mount /data/rootfs.img /target
		mount /data/system.img /target/system
		mount --bind /data /target/data
		exit
	SHELL
}

umount_all()
{
	adb shell <<-SHELL
		umount -rl /target
		exit
	SHELL
}

mount_all > /dev/null

CHROOT='TERM=linux HOME=/root PATH=/sbin:/bin:/usr/sbin:/usr/bin:$PATH chroot /target'
LINES=$(tput lines)
COLUMNS=$(tput cols)

if [ $# -eq 0 ]
then # Interactive shell
	if [ $(which tmux) ]
	then # with tmux installed
		TARGET="halium-adb-$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 8 | head -n 1)"
		if [ $TMUX ]
		then # create new window if we are in a tmux session
			tmux new-window -n $TARGET -d 'adb shell'
			SWITCH='select-window'
		else # create a new tmux session if none exists
			tmux new-session -s $TARGET -d 'adb shell'
			SWITCH='attach-session'
			let LINES-=1
		fi
		sleep 1
		tmux send-keys -t $TARGET "export LINES=${LINES}; export COLUMNS=${COLUMNS}"$'\n'
		tmux send-keys -t $TARGET "${CHROOT} /bin/bash; exit"$'\n'
		tmux $SWITCH -t $TARGET
	else # without tmux installed
		echo 'To automatically get an interactive chroot session, install'
		echo 'The program "tmux". To enter the chroot environment run:'
		echo
		echo "${CHROOT} /bin/bash"
		echo
		adb shell
	fi
else # Non-interactive command
	adb shell "${CHROOT} /bin/bash -c \"${@}\""
fi

umount_all > /dev/null