Deepin Live CD Build tool. 

This tool is used to build deepin Live CDs, it can also used to build
customized Live CD based on Ubuntu (and future on Debian, too).

-- Contents --
* 1. Basic Usage
* 2. Actions
* 3. Options
* 4. Configuration files
* 5. Known issues

1. Basic Usage
First, use the following command to install required tools to build Deepin
Live CD:
    
    ./mkiso init

Then just type the following command:

  ./mkiso base custom casper iso zsync hashsum

it will build the latest Deepin Live CD image in ./output, with the same 
arch of your host. 

2. Actions
The build process contain several actions, do_init, do_base, do_custom, 
do_casper, do_iso, do_zsync, do_hashsum and do_bt.

do_init: 
    This action only have to be performed once on a host, it will
    install the required tools to build lice cd iso images.

do_base: 
    Use debootstrap to build a base system, and then install some 
    packages in the base system. The mirror used to build base system and
    codename can be set in ./mkiso.conf. Other options also can be set via
    cmd params and/or in ./mkiso.conf

do_custom: 
    Do some more custom stuff in the base system. 

do_casper:
    Setup casper dir for Live CD, which is required by casper package, 
    used to boot the live cd.

do_iso:
    Generate other files for Live CD, and finaly genisoimage.

do_zsync:
    Make zsync index file, for zsync clients to download.

do_hashsum:
    Calculate md5sum, sha1sum and sha256sum for all iso images in the output
    dir.

do_bt:
    Generate torrent file for bt download. This action is not implemented yet.

3. Options
There are several options you can specify on command line.

-arch=i386|amd64
    By default, the script will build a live cd of the host arch. On x86_64
    host, you can also build i386 live cd. However, you can not do vice
    versa.

-scheme=SCHEME
    You may have different schemes like ubuntu-desktop, kubuntu, xubuntu, 
    etc. You just have to write configuration files for different schemes,
    and let the script use them. The default scheme is "default", which is
    a symbol link to desktop, you can change it to other scheme by changing
    the link destination of ./conf/VERSION/default.

-version=11.12|12.06|...
    Which version of your system you are going to build. The default 
    version is "current", which is a symbol link to 11.12 currently. You 
    can change it to other version by changing the link destination of 
    ./conf/current.

-output=FILENAME
    The filename of output iso image. The default is:
    ${DISTRO_NAME}-${SCHEME}-${ARCH}.iso

-outputbase=OUTPUT_BASE
    Where to put output files (*.iso, MD5SUMS, *.zsync, etc.)
    The output dir will be:
    ${OUTPUT_BASE}/${VERSIOn}/${SCHEME}/daily-live/$(date +%Y%m%d)/

-buildbase=BUILD_BASE
    Where to put temp file for build process. The base system and iso 
    filesystem structure will be put in:
    ${BUILD_BASE}/${VERSION}/${SCHEME}/${ARCH}/{chroot,iso}
    It is recommend to mount a 4g or larger tmpfs on BUILD_BASE to speedup
    the build process if you have sufficient memory:

    # mount -t tmpfs -o size=4g tmpfs BUILD_BASE/

-copy-chroot-path=COPY_CHROOT_PATH
    If you already have a CHROOT dir on which a full do_base is done, you
    can tell the script to skip the do_base action, and copy files from
    COPY_CHROOT_PATH to save time. 

    do_base is a quite time coconsuming task, but it is quite stable in a 
    short time. So you only have to performance do_base once a day or a 
    week, except for major script modifications.

-backup-chroot-path=BACKUP_CHROOT_PATH
    If you specified a BACKUP_CHROOT_PATH, after do_base is done, the 
    script will copy the CHROOT dir to BACKUP_CHROOT_PATH, so the next time
    you can use -copy-chroot-path to save time.

4. Configuration files
There are several configuration files to help build the live cd. There are 
mainly two types of configuration files, suffixed with .conf and .sh.
Both of them are written as bash script, but usually, we only do VARIABLE
assignment in .conf files, and may do more actions in .sh files. They are 
not meant to be executed seperately, so they do not have x permission, they
are sourced in the main script, mkiso.

Very commonly, you will have some local configurations, like the mirror to
use in debootstrap phase, you can create a "local version" of .conf files.
e.g. you can create a conf/current/default/mkiso.conf.local, in which you 
can overwrite variables set in .../mkiso.conf. All .local files are sourced
after the relevant .conf file, if exists. *.local files are not tracked by
git.

./mkiso.conf{,.local}
   Global settings for building live cd. You can set OUTPUT_BASE, 
   BUILD_BASE, LOG_BASE, etc in this file.

./conf/${VERSION}/${SCHEME}/mkiso.conf{,.local}
   Settings related to the to-be-build live cd, like DISTRO_NAME, 
   CODENAME, etc.

./conf/${VERSION}/${SCHEME}/custom.chroot.sh
    This script will be copied to the CHROOT_PATH and executed in chroot 
    evn, by do_custom action.

./conf/${VERSION}/${SCHEME}/custom.sh
    This script is also executed by do_custom aciton, but no in the host
    env. This script is invoked after custom.chroot.sh.

5. Known issues
    1) This tool can be used on any distro that have debootstrap tool. On
    distros which do not have APT system, you will have to modify do_init
    action to use the right package manager to install the required tools.
    There may be also other issues, you have to find out yourself, I haven't
    tested it on any distro other than debian/ubuntu/deepin.

    2) On some distros with old debootstrap, it may not contain the codename
    you want to use, e.g., on Debian Squeeze, there is not "oneiric" in 
    debootstrap script, you should upgrade debootstrap youself. Most codename
    share the same debootstrap scripts, so you can just make a soft link other
    than upgrade debootstrap:

    ln -s gutsy /usr/share/debootstrap/scripts/oneiric

    3) On Debian sid, there is a bug while installing cups-pdf package in 
    chroot env, the dpkg will pause and wait the user to hit enter to 
    continue. The same problem doesn't appear with Debian Squeeze and Ubuntu.