#! /bin/sh
### -*-sh-*-
###
### Make autoconf-like substitutions in files
###
### (c) 2008 Mark Wooding
###

###----- Licensing notice ---------------------------------------------------
###
### This file is part of the Common Files Distribution (`common').
###
### `Common' is free software; you can redistribute it and/or modify
### it under the terms of the GNU General Public License as published by
### the Free Software Foundation; either version 2 of the License, or
### (at your option) any later version.
###
### `Common' is distributed in the hope that it will be useful,
### but WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
### GNU General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with `common'; if not, write to the Free Software Foundation,
### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

set -e
VERSION="@VERSION@"

###--------------------------------------------------------------------------
### Parse command line arguments.

while [ $# -gt 0 ]; do
  case $1 in
    -h | --h | --he | --hel | --help)
      cat <<EOF
Usage: confsubst FILE TAG=VALUE...

Replaces occurrences of @TAG@ in FILE with VALUE, and writes the result to
standard output.
EOF
      exit 0
      ;;
    -v | --v | --ve | --ver | --vers | --versi | --versio | --version)
      echo "confsubst: Common Files Distribution version $VERSION"
      exit 0
      ;;
    --)
      shift
      break
      ;;
    -)
      break
      ;;
    -*)
      echo "confsubst: unknown option \`$1'" >&2
      exit 1
      ;;
    *)
      break
      ;;
  esac
  shift
done

if [ $# -lt 1 ]; then
  echo >&2 "Usage: confsubst FILE TAG=VALUE..."
  exit 1
fi
file=$1; shift

###--------------------------------------------------------------------------
### Main code.

subst=""
for fixup; do
  case "$fixup" in
    *?=*?) ;;
    *) echo >&2 "$0: bad substitution: $fixup"; exit 1 ;;
  esac
  tag=$(echo "$fixup" | sed 's/=.*$//') && \
  value=$(echo "$fixup" | sed 's/^[^=]*=//') && \
  subst="$subst s@$tag@$valueg;"
done

sed "$subst" $file || exit $?

###----- That's all, folks --------------------------------------------------