add proxy support in install-chroot.sh

build/install-chroot.sh

 #!/bin/bash -e
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script installs Debian-derived distributions in a chroot environment.
 # It can for example be used to have an accurate 32bit build and test
 # environment when otherwise working on a 64bit machine.
 # N. B. it is unlikely that this script will ever work on anything other than a
@@ skipping 321 matching lines @@
 # whether it is the beginning of a new entry.
 sudo sed -ni '/^[[]'"${target%bit}"']$/,${:1;n;/^[[]/b2;b1;:2;p;n;b2};p'       \
          /etc/schroot/schroot.conf
 
 # Download base system. This takes some time
 if [ -z "${mirror}" ]; then
  grep -qs ubuntu.com /usr/share/debootstrap/scripts/"${distname}" &&
    mirror="http://archive.ubuntu.com/ubuntu" ||
    mirror="http://ftp.us.debian.org/debian"
 fi
- sudo debootstrap ${archflag} "${distname}" /var/lib/chroot/"${target}"        \
-                  "$mirror"
+
+if [ -n "${http_proxy}" ]; then
+  PROXY_FLAG="http_proxy=${http_proxy}"
+else
+  PROXY_FLAG=""
+fi
+sudo ${PROXY_FLAG} debootstrap ${archflag} "${distname}"   \

[Markus (顧孟勤), 2012/05/08 02:09:57]

You could probably write this more concisely as:

sudo ${http_proxy:+http_proxy="${http_proxy}"} debootstrap ...

This also has the advantage that it gets the quoting right. If "${http_proxy}"
contains white-space, we'll still forward it correctly.

But if you strongly feel your version is better, I won't fight you over it --
although I'd love if you could then fix the quoting somehow.

[Wei James(wistoch), 2012/05/08 02:47:58]

done. thanks 

+  "/var/lib/chroot/${target}"  "$mirror"
 
 # Add new entry to /etc/schroot/schroot.conf
 grep -qs ubuntu.com /usr/share/debootstrap/scripts/"${distname}" &&
   brand="Ubuntu" || brand="Debian"
 if [ -z "${chroot_groups}" ]; then
   chroot_groups="${admin},$(id -gn)"
 fi
 # Older versions of schroot wanted a "priority=" line, whereas recent
 # versions deprecate "priority=" and warn if they see it. We don't have
 # a good feature test, but scanning for the string "priority=" in the
@@ skipping 191 matching lines @@
       >>"/var/lib/chroot/'"${target}"'/etc/apt/sources.list"'
 fi
 
 # Add source repositories, if the user requested we do so
 [ "${add_srcs}" = "y" -a \
   -r "/var/lib/chroot/${target}/etc/apt/sources.list" ] &&
 sudo sed -i '/^deb[^-]/p
              s/^deb\([^-]\)/deb-src\1/' \
          "/var/lib/chroot/${target}/etc/apt/sources.list"
 
+# Set apt proxy if host has set http_proxy
+if [ -n "${http_proxy}" ]; then
+  sudo sh -c '
+    echo "Acquire::http::proxy \"'${http_proxy}'\";" \

[Markus (顧孟勤), 2012/05/08 02:09:57]

While it probably is benign in this particular case, we try to always put
double-quotes around any environment variable, especially if it was provided by
the user. This is not always possible, but here you could trivially add it.
Please do so, as it will make things easier for future reviewers -- they won't
have to scratch their heads whether there was a reason why we left of the
quotes.

[Wei James(wistoch), 2012/05/08 02:47:58]

for the syntax requirement, we need a double-quotes in apt.conf such as: 
Acquire::http::proxy "http://proxy.com:8080";

So i used it in this way. 

I am not very familar with shell, can you tell me how can I get double-quotes in
the echo statement around the  environment variable? thanks 

+        >>"/var/lib/chroot/'"${target}"'/etc/apt/apt.conf"'
+fi
+
 # Update packages
 sudo "/usr/local/bin/${target%bit}" /bin/sh -c '
   apt-get update; apt-get -y dist-upgrade' || :
 
 # Install a couple of missing packages
 for i in debian-keyring ubuntu-keyring locales sudo; do
   [ -d "/var/lib/chroot/${target}/usr/share/doc/$i" ] ||
     sudo "/usr/local/bin/${target%bit}" apt-get -y install "$i" || :
 done
 
@@ skipping 225 matching lines @@
 
 For Chrome, this probably means you want to make your "out" directory a
 symbolic link that points somewhere inside of "${HOME}/chroot".
 
 You still need to run "gclient runhooks" whenever you switch from building
 outside of the chroot to inside of the chroot. But you will find that you
 don't have to repeatedly erase and then completely rebuild all your object
 and binary files.
 
 EOF