dockerlib: extract initcontainer() method

This helps contain all the logic around creating containers.

contrib/dockerlib.sh

@@ -1,19 +1,35 b''
 #!/bin/sh -eu
 
 # This function exists to set up the DOCKER variable and verify that
 # it's the binary we expect. It also verifies that the docker service
 # is running on the system and we can talk to it.
 function checkdocker() {
   if which docker.io >> /dev/null 2>&1 ; then
     DOCKER=docker.io
   elif which docker >> /dev/null 2>&1 ; then
     DOCKER=docker
   else
     echo "Error: docker must be installed"
     exit 1
   fi
 
   $DOCKER -h 2> /dev/null | grep -q Jansens && { echo "Error: $DOCKER is the Docking System Tray - install docker.io instead"; exit 1; }
   $DOCKER version | grep -q "^Client version:" || { echo "Error: unexpected output from \"$DOCKER version\""; exit 1; }
   $DOCKER version | grep -q "^Server version:" || { echo "Error: could not get docker server version - check it is running and your permissions"; exit 1; }
 }
+
+# Construct a container and leave its name in $CONTAINER for future use.
+function initcontainer() {
+  [ "$1" ] || { echo "Error: platform name must be specified"; exit 1; }
+
+  DFILE="$ROOTDIR/contrib/docker/$1"
+  [ -f "$DFILE" ] || { echo "Error: docker file $DFILE not found"; exit 1; }
+
+  CONTAINER="hg-dockerrpm-$1"
+  DBUILDUSER=build
+  (
+    cat $DFILE
+    echo RUN groupadd $DBUILDUSER -g `id -g`
+    echo RUN useradd $DBUILDUSER -u `id -u` -g $DBUILDUSER
+  ) | $DOCKER build --tag $CONTAINER -
+}

contrib/dockerrpm

@@ -1,48 +1,37 b''
 #!/bin/bash -e
 
 . $(dirname $0)/dockerlib.sh
 
 BUILDDIR=$(dirname $0)
-ROOTDIR=$(cd $BUILDDIR/..; pwd)
+export ROOTDIR=$(cd $BUILDDIR/..; pwd)
 
 checkdocker
 
 PLATFORM="$1"
-[ "$PLATFORM" ] || { echo "Error: platform name must be specified"; exit 1; }
 shift # extra params are passed to buildrpm
 
-DFILE="$ROOTDIR/contrib/docker/$PLATFORM"
-[ -f "$DFILE" ] || { echo "Error: docker file $DFILE not found"; exit 1; }
-
-CONTAINER="hg-dockerrpm-$PLATFORM"
-
-DBUILDUSER=build
-(
-cat $DFILE
-echo RUN groupadd $DBUILDUSER -g `id -g`
-echo RUN useradd $DBUILDUSER -u `id -u` -g $DBUILDUSER
-) | $DOCKER build --tag $CONTAINER -
+initcontainer $PLATFORM
 
 RPMBUILDDIR=$ROOTDIR/packages/$PLATFORM
 contrib/buildrpm --rpmbuilddir $RPMBUILDDIR --prepare $*
 
 DSHARED=/mnt/shared
 $DOCKER run -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
     rpmbuild --define "_topdir $DSHARED" -ba $DSHARED/SPECS/mercurial.spec --clean
 
 $DOCKER run -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
     createrepo $DSHARED
 
 cat << EOF > $RPMBUILDDIR/mercurial.repo
 # Place this file in /etc/yum.repos.d/mercurial.repo
 [mercurial]
 name=Mercurial packages for $PLATFORM
 # baseurl=file://$RPMBUILDDIR/
 baseurl=http://hg.example.com/build/$PLATFORM/
 skip_if_unavailable=True
 gpgcheck=0
 enabled=1
 EOF
 
 echo
 echo "Build complete - results can be found in $RPMBUILDDIR"