contrib/dockerlib.sh

repoview: fix corrupted hiddencache crash Mercurial (issue5042)

Before this patch if the hiddencache existed but was empty, it would crash
mercurial. This patch adds exception handling when reading the hiddencache to
avoid the issue.
When encountering a corrupted cache file we print a devel warning. There would
be no point in issuing a normal warning as the user wouldn't be able to do
anything about the situation.

The warning looks like:

devel-warn: corrupted hidden cache, removing it at: /path/to/repoview.py

#!/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; }
  $DOCKER version | grep -Eq "^Client( version)?:" || { echo "Error: unexpected output from \"$DOCKER version\""; exit 1; }
  $DOCKER version | grep -Eq "^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
    if [ $(uname) = "Darwin" ] ; then
        # The builder is using boot2docker on OS X, so we're going to
        # *guess* the uid of the user inside the VM that is actually
        # running docker. This is *very likely* to fail at some point.
        echo RUN useradd $DBUILDUSER -u 1000
    else
        echo RUN groupadd $DBUILDUSER -g `id -g` -o
        echo RUN useradd $DBUILDUSER -u `id -u` -g $DBUILDUSER -o
    fi
  ) | $DOCKER build --tag $CONTAINER -
}