launchpad-reviewers team mailing list archive

[Scott Moser <smoser@xxxxxxxxxx>]

Scott Moser has proposed merging lp:~smoser/maas/packaging.1231693-2 into lp:~maas-maintainers/maas/packaging.

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)
Related bugs:
  Bug #1231693 in MAAS: "maas-dhcp backport does not start on precise"
  https://bugs.launchpad.net/maas/+bug/1231693

For more details, see:
https://code.launchpad.net/~smoser/maas/packaging.1231693-2/+merge/188967

One of these 2 branches can be chosen.  Either
a. 
https://code.launchpad.net/~smoser/maas/packaging.1231693-2/+merge/188967
or
https://code.launchpad.net/~smoser/maas/packaging.1231693/+merge/188932

I'm really OK with either.  One is more complex but supports more scenarios (this one)
the other is a simpler upstart job that only supports one version of isc-dhcp (quantal-saucy version).

-- 
https://code.launchpad.net/~smoser/maas/packaging.1231693-2/+merge/188967
Your team Launchpad code reviewers is requested to review the proposed merge of lp:~smoser/maas/packaging.1231693-2 into lp:~maas-maintainers/maas/packaging.

=== modified file 'debian/control'
--- debian/control	2013-10-02 19:37:31 +0000
+++ debian/control	2013-10-03 00:44:27 +0000
@@ -249,7 +249,7 @@
 
 Package: maas-dhcp
 Architecture: all
-Depends: isc-dhcp-server, ${misc:Depends}
+Depends: isc-dhcp-server (>= 4.2.4), ${misc:Depends}
 Breaks: maas-dhcp (<= 0.1+bzr777+dfsg-0ubuntu1)
 Replaces: maas-dhcp (<= 0.1+bzr777+dfsg-0ubuntu1)
 Description: Ubuntu MAAS Server - DHCP Configuration (meta-package)

=== modified file 'debian/maas-dhcp.maas-dhcp-server.upstart'
--- debian/maas-dhcp.maas-dhcp-server.upstart	2013-05-21 13:17:57 +0000
+++ debian/maas-dhcp.maas-dhcp-server.upstart	2013-10-03 00:44:27 +0000
@@ -5,9 +5,7 @@
 stop on runlevel [!2345]
 
 env CONFIG_FILE=/etc/maas/dhcpd.conf
-env PID_DIR=/run/maas/dhcp
 env PID_FILE=/run/maas/dhcp/dhcpd.pid
-env LEASES_DIR=/var/lib/maas/dhcp
 env LEASES_FILE=/var/lib/maas/dhcp/dhcpd.leases
 
 # This is where we write what interfaces dhcpd should listen on.
@@ -37,32 +35,64 @@
 
 respawn
 script
-    RELEASE=`lsb_release --codename --short`
+    dhcpd_bugmode() {
+        # bug 1231988 and bug 1231693 have more information.
+        # return one of 'precise', or 'quantal'
+        # indicating if isc-dhcp behaves like it did on precise,
+        # like on quantal (through saucy at least)
+
+        local dver=""
+        # first figure out what the version is
+        dver=$(dpkg-query --showformat '${Version}\n' \
+                   --show isc-dhcp-server 2>/dev/null) || :
+        if [ -z "$dver" ]; then
+            # dpkg query failed. try --version
+            dver=$(dhcpd --version 2>&1) && dver=${dver#isc-dhcpd-} &&
+                 [ "${dver#[456]}" != "${dver}" ] || dver=""
+        fi
+
+        if [ -z "$dver" ]; then
+            echo "FAIL: could not get dhcpd version!"
+            exit 1
+        fi
+
+        # precise shipped 4.1, quantal shipped 4.2.4
+        if dpkg --compare-versions "$dver" lt 4.2.4; then
+            BUGMODE="precise"
+        else
+            BUGMODE="quantal"
+        fi
+    }
+
     INTERFACES=`cat "${INTERFACES_FILE}"`
 
-    # Allow dhcp server to write lease and pid file.
-    mkdir -p $PID_DIR
-    chown dhcpd:dhcpd $PID_DIR
-
-    # As of Quantal, the leases file must be owned by root:root (even though
-    # the daemon will run under an unprivileged user).
-    # In Precise, ownership was supposed to be dhcpd:dhcpd.
-    mkdir -p $LEASES_DIR
-    if [ "$RELEASE" = "precise" ]; then
-        owner_group="dhcpd:dhcpd"
-        dhcpd_owner_opts=""
+    PID_D=${PID_FILE%/*}
+    LEASES_D=${LEASES_FILE%/*}
+
+    # we operate on leases~ only if it exists
+    LEASES_TILDA="${LEASES_FILE}~"
+    [ -e "$LEASES_TILDA" ] || LEASES_TILDA=""
+
+    mkdir -p $PID_D $LEASES_D
+    chown dhcpd:dhcpd $PID_D
+
+    touch $LEASES_FILE
+
+    dhcpd_bugmode
+    if [ "$BUGMODE" = "precise" ]; then
+        # the daemon runs as dhcpd even without -user and -group opts
+        chown dhcpd:dhcpd $LEASES_D $LEASES_TILDA $LEASES_FILE
+        USER_GROUP_OPTS=""
+    elif [ "$BUGMODE" = "quantal" ]; then
+        # bug 1231988 is present
+        chown root:root   $LEASES_D $LEASES_TILDA $LEASES_FILE
+        USER_GROUP_OPTS="-u dhcpd -g dhcpd"
     else
-        owner_group="root:root"
-        dhcpd_owner_opts="-user dhcpd -group dhcpd"
+        echo "FAIL: unknown dhcpd_bugmode '$BUGMODE'"
+        exit 1
     fi
-    chown $owner_group $LEASES_DIR
-    [ -e $LEASES_FILE ] || touch $LEASES_FILE
-    for LFILE in $LEASES_FILE $LEASES_FILE~; do
-        if [ -e $LFILE ]; then
-            chown $owner_group $LFILE
-            chmod a+r $LFILE
-        fi
-    done
-
-    exec /usr/sbin/dhcpd ${dhcpd_owner_opts} -f -q -4 -pf $PID_FILE -cf $CONFIG_FILE -lf $LEASES_FILE $INTERFACES
+
+    exec /usr/sbin/dhcpd $USER_GROUP_OPTS -f -q -4 -pf $PID_FILE \
+        -cf $CONFIG_FILE -lf $LEASES_FILE $INTERFACES
+
 end script