libbutl/manifest-serializer.bash.in


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# file      : libbutl/manifest-serializer.bash.in
# copyright : Copyright (c) 2014-2018 Code Synthesis Ltd
# license   : MIT; see accompanying LICENSE file

if [ "$butl_manifest_serializer" ]; then
  return 0
else
  butl_manifest_serializer=true
fi

@import libbutl/utility@

# Serialize the manifest reading the binary representation from stdin and
# writing to stdout.
#
# Normally you would use the start/finish functions below.
#
function butl_serialize_manifest ()
{
  local n v
  while IFS=: read -r -d '' n v; do
    printf "$n: $v\n"
  done
}

# Start the manifest serialization co-process setting the following "return"
# variables:
#
#   butl_manifest_serializer_ifd
#   butl_manifest_serializer_ofd
#   butl_manifest_serializer_pid
#
# If <file> is not specified, then write to stdout.
#
# The typical usage:
#
#   butl_manifest_serializer_start
#
#   fd="$butl_manifest_serializer_ifd"
#
#   printf ":1\0"             >&"$fd"
#   printf "name:foo\0"       >&"$fd"
#   printf "version:1.2.3\0"  >&"$fd"
#
#   butl_manifest_serializer_finish
#
function butl_manifest_serializer_start () # [<file>]
{
  if [ "$#" -gt 0 ]; then
    exec {butl_manifest_serializer_ofd}>"$1"
  else
    exec {butl_manifest_serializer_ofd}>&1
  fi

  # See notes in butl_manifest_parser_start() on bash co-process issues.
  #
  coproc { butl_serialize_manifest; } >&"$butl_manifest_serializer_ofd"
  butl_manifest_serializer_ifd="${COPROC[1]}"
  butl_manifest_serializer_pid="$COPROC_PID"
}

# Finish the manifest serialization co-process.
#
function butl_manifest_serializer_finish ()
{
  exec {butl_manifest_serializer_ifd}<&-
  wait "$butl_manifest_serializer_pid"
  exec {butl_manifest_serializer_ofd}<&-
}