Allow arbitrary stage tarball to be used

[nephros]

It would be nice if we could use arbitrary stage tarballs to be used for creation. This would allow for easy deployment of custom setups.

[nephros]

This is a clumsy modification to the lxc-gentoo script I use to run the x32 stage3 in a container.

It allows a new -C URL parameter which will fetch and unpack custom tarballs.

Test with "lxc-gentoo-custom create -i dhcp -a amd64 -n lxc_x32 -u lxc_x32 -C http://dev.gentoo.org/~vapier/x32/stage3-amd64-x32-20120605.tar.xz

--- lxc-gentoo  2012-06-18 12:19:09.000000000 +0200
+++ lxc-gentoo-custom   2012-06-18 19:37:27.000000000 +0200
@@ -380,13 +380,18 @@

     # make unique variables for x86 and amd64 since stage3 url are different
     echo -n "Generating strings to run... "
-    if [ $ARCH == 'x86' ]; then
-      STAGE3SED="s/.*stage3-${SUBARCH}-\(........\)\.tar\.bz2.*/\1/p"
-      STAGE3URL="http://distfiles.gentoo.org/releases/${ARCH}/autobuilds/current-stage3/stage3-${SUBARCH}"
-    else
-      STAGE3SED="s/.*stage3-${ARCH}-\(........\)\.tar\.bz2.*/\1/p"
-      STAGE3URL="http://distfiles.gentoo.org/releases/${ARCH}/autobuilds/current-stage3/stage3-${ARCH}"
-    fi
+       if [ x"$CUSTOMURL" = x"" ]; then
+          if [ $ARCH == 'x86' ]; then
+             STAGE3SED="s/.*stage3-${SUBARCH}-\(........\)\.tar\.bz2.*/\1/p"
+             STAGE3URL="http://distfiles.gentoo.org/releases/${ARCH}/autobuilds/current-stage3/stage3-${SUBARCH}"
+           else
+             STAGE3SED="s/.*stage3-${ARCH}-\(........\)\.tar\.bz2.*/\1/p"
+             STAGE3URL="http://distfiles.gentoo.org/releases/${ARCH}/autobuilds/current-stage3/stage3-${ARCH}"
+           fi
+       else
+            STAGE3SED="s/.*stage3-${ARCH}-\(........\)\.tar\.[xb]z[2].*/\1/p"
+            STAGE3URL=$CUSTOMURL
+       fi

                echo -n "Determining latest ${DISTRO} ${ARCH} stage3 archive... "
                mkdir -p ${CACHE} 1>/dev/null 2>/dev/null
@@ -394,7 +399,12 @@
                echo ${LATEST_STAGE3_TIMESTAMP}

                echo -n "Downloading (~120MB), please wait... "
-               ${WGET} -O ${CACHE}/stage3-${ARCH}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2 "${STAGE3URL}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2" 1>/dev/null 2>/dev/null
+               if [ x"$CUSTOMURL" = x"" ]; then
+                       ${WGET} -O ${CACHE}/stage3-${ARCH}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2 "${STAGE3URL}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2" 1>/dev/null 2>/dev/null
+               else
+                       echo ${WGET} -O ${CACHE}/"${CUSTOMURL##*/}" "${CUSTOMURL}"
+                       ${WGET} -O ${CACHE}/"${CUSTOMURL##*/}" "${CUSTOMURL}" 1>/dev/null 2>/dev/null
+               fi

                RESULT=$?
                if [ "${RESULT}" != "0" ]; then
@@ -408,7 +418,16 @@
                mkdir -p "${TEMPLATE}" #1>/dev/null 2>/dev/null

                echo -n "Extracting stage3 archive... "
-               tar -jxf ${CACHE}/stage3-${ARCH}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2 -C "${TEMPLATE}" 1>/dev/null 2>/dev/null
+               if [ x"$CUSTOMURL" = x"" ]; then
+                       tar -jxf ${CACHE}/stage3-${ARCH}-${LATEST_STAGE3_TIMESTAMP}.tar.bz2 -C "${TEMPLATE}" 1>/dev/null 2>/dev/null
+               else
+                       tar xvf ${CACHE}/"${CUSTOMURL##*/}" -C "${TEMPLATE}" 1>/dev/null 2>/dev/null
+               fi
+               RESULT=$?
+               if [ "${RESULT}" != "0" ]; then
+                   echo "failed!"
+                   exit 1
+               fi
                echo "done."
                echo -n "Downloading ${DISTRO} portage (software database) snapshot... "
                rm -f ${CACHE}/portage-latest.tar.bz2 1>/dev/null 2>/dev/null
@@ -524,6 +543,9 @@
        -p GUESTROOTPASS : password for root account
                Env. Var.: GUESTROOTPASS
                Current/Default: ${GUESTROOTPASS}
+       -C CUSTOMURL : URL for a custom tarball
+               Env. Var.: CUSTOMURL
+               Current/Default: ${CUSTOMURL}

 This script is a helper to create ${DISTRO} system containers.

@@ -587,7 +609,7 @@
 CACHE="/var/cache/lxc/${DISTRO}"

 OPTIND=2
-while getopts "i:g:n:u:a:p:q" opt
+while getopts "i:g:n:u:a:p:qC:" opt
 do
         case $opt in
                 i) IPV4=$OPTARG ;;
@@ -595,6 +617,7 @@
                 n) NAME=$OPTARG ;;
                 u) UTSNAME=$OPTARG ;;
                 a) ARCH=$OPTARG ;;
+                           C) CUSTOMURL=$OPTARG;;
                p) GUESTROOTPASS=$OPTARG ;;
                q) QUIET=Yes ;;
                 \?) ;;

[globalcitizen]

While I support the feature request this patchfile won't apply cleanly to the latest code on git. If you can supply the same changes as a pull request against the current codebase, I will happily apply it for you.