ubuntu2004的chroot环境

工作需要ubuntu2004的chroot开发环境，故这里记录搭建ubuntu2004的chroot环境。

镜像地址

如下：

https://releases.ubuntu.com/20.04.6/

获取环境


mkdir iso && mount ubuntu-20.04.6-desktop-amd64.iso iso/
unsquashfs iso/casper/filesystem.squashfs
umount iso && rm -rf iso

准备chroot

为了能够chroot的一些编译工作正常，更真实的模拟实际环境，这里需要和linux启动一致，挂载必要的文件系统如下：


vim 1-chroot
#!/bin/bash

CHROOT_DIR=/root/sdk/chroot/squashfs-root
[ ! -d ${CHROOT_DIR} ] && exit
cd ${CHROOT_DIR}
mountpoint -q ./proc || mount -t proc proc ./proc
mountpoint -q ./sys || mount -t sysfs sysfs ./sys
mountpoint -q ./dev || mount -t devtmpfs devtmpfs ./dev
mountpoint -q ./dev/pts || mount -t devpts devpts ./dev/pts

chroot .

为了能够全局使用，可以放在/usr/local/sbin/下面


mv 1-chroot /usr/local/sbin/

到这里，chroot环境已经基本成型，下面需要针对这个chroot环境做一些易用的改动。

配置源

配置源之前先设置dns，这里是chroot环境，所以直接修改resolv.conf文件，这里以114为例


nameserver 114.114.114.114

然后修改源地址为国内，修改文件/etc/apt/sources.list如下


deb http://mirrors.aliyun.com/ubuntu/ focal main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal universe
deb http://mirrors.aliyun.com/ubuntu/ focal-updates universe
deb http://mirrors.aliyun.com/ubuntu/ focal multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal-security universe
deb http://mirrors.aliyun.com/ubuntu/ focal-security multiverse

最后update一下即可

禁止一些低级操作

为了避免reboot和一些低级操作，这里需要处理一下（在特殊情况下会生效），故如下


vim /etc/profile.d/chroot.sh
hint_reboot(){
        info="Forbidden reboot!"
        echo -e "\033[31m${info}\033[0m"
}
hint_poweroff(){
        info="Forbidden poweroff!"
        echo -e "\033[31m${info}\033[0m"
}
hint_halt(){
        info="Forbidden halt!"
        echo -e "\033[31m${info}\033[0m"
}

alias reboot='hint_reboot'
alias poweroff='hint_poweroff'
alias halt='hint_halt'

提示chroot

为了提示自己是在chroot环境中，修改bashrc如下：


vim /root/.bashrc

# 1.修改TERM为xterm-color
TERM=xterm-color
cd
source /etc/profile.d/chroot.sh

# 2.修改\h为chroot
 54 if [ "$color_prompt" = yes ]; then
 55     # PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
 56     PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@chroot\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
 57 else
 58     PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
 59 fi
    ......

装包

基础开发环境包安装


apt-get install git ssh make gcc libssl-dev liblz4-tool expect \
g++ patchelf chrpath gawk texinfo chrpath diffstat binfmt-support \
qemu-user-static live-build bison flex fakeroot cmake gcc-multilib \
g++-multilib unzip device-tree-compiler ncurses-dev rsync gdb-multiarch \
openocd qemu-system-arm cargo doxygen

apt-get install libgucharmap-2-90-dev bzip2 expat gpgv2 \
cpp-aarch64-linux-gnu libgmp-dev libmpc-dev bc python-is-python3 \
python2 libsqlite3-dev esmtp codespell python-ply mutt tig u-boot-tools \
meson ninja-build u-boot-tools build-essential devscripts breeze-dev \
debhelper extra-cmake-modules libcap-dev libxcb-composite0-dev \
libdrm-dev libgbm-dev libxcb-cursor-dev libxcb-damage0-dev \
libxcb-glx0-dev libxcb-randr0-dev libxcb-util-dev

# 可能出现图形化服务器选择lightdm/gdm
apt-get install libtool qtmultimedia5-dev \
libdbusmenu-qt5-dev libfcitx-qt5-dev libfcitx5-qt-dev \
libgsettings-qt-dev libkf5bluezqt-dev libkf5networkmanagerqt-dev \
liblightdm-qt5-3-dev libpolkit-qt5-1-dev libpoppler-qt5-dev \
libqt5charts5-dev libqt5opengl5-dev libqt5sensors5-dev \
libqt5svg5-dev libqt5texttospeech5-dev libqt5virtualkeyboard5-dev \
libqt5waylandclient5-dev libqt5webchannel5-dev libqt5webkit5-dev \
libqt5x11extras5-dev libqt5xdg-dev libqt5xdgiconloader-dev \
libqtav-dev libqtav-private-dev qt5-default qtbase5-dev \
qtbase5-dev-tools qtbase5-private-dev qtchooser \
qtconnectivity5-dev qtdeclarative5-dev qtdeclarative5-dev-tools \
qtdeclarative5-private-dev qtlocation5-dev qtmultimedia5-dev \
qtpositioning5-dev qtquickcontrols2-5-dev qtscript5-dev \
qttools5-dev qttools5-dev-tools qtwayland5-dev-tools  \
qtwebengine5-dev qtwebengine5-private-dev libkdecorations2-dev \
libkf5xmlgui-dev libkf5crash-dev kscreenlocker-dev kinit-dev pkg-kde-tools

打包

umount dev/pts dev proc sysfs && cd ..
tar cvzf ubuntu-2004-develop.tar.gz squashfs-root/
至此获得ubuntu-2004-develop.tar.gz是可用于x86的ubuntu2004的chroot

导入docker

docker import ubuntu-2004-develop.tar.gz x86-ubuntu2004-dev:v1
这样docker内也能正常使用此环境

目录