Write a library to handle control file fields.

1 files changed, 110 insertions, 0 deletions

diff --git a/lib/controlfields b/lib/controlfields
new file mode 100644
index 0000000..7eda765
--- /dev/null
+++ b/lib/controlfields
@@ -0,0 +1,110 @@
+#! /bin/sh
+#
+# opkhelper
+# lib/controlfields
+# Functions for parsing control fields.
+#
+# Copyright (C) 2012 Patrick "P. J." McDermott
+#
+# This program 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 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Gets a simple control field.
+# Parameters:
+#   package name (if omitted, source package control file is read)
+#   field name
+# Output:
+#   field value
+# Return value:
+#   0 on success
+#   1 on missing field
+#   255 on invalid invocation
+#oh_get_simple_field()
+#{
+#	case ${#} in
+#		1)
+#			_control=../control
+#			_field=${1}
+#			;;
+#		2)
+#			_control=../${1}.pkg/control
+#			_field=${2}
+#			;;
+#		*)
+#			return 255
+#			;;
+#	esac
+#
+#	_value=`sed -n "s/^${_field}:[[:space:]]*\([[:space:]]\)[[:space:]]*$/\\1/p"
+#		${_control}`
+#
+#	[ -z "${_value}" ] && return 1
+#	echo "${_value}"
+#	return 0
+#}
+
+# Gets a folded or multiline control field.
+# Parameters:
+#   package name (if omitted, source package control file is read)
+#   field name
+# Output:
+#   field value
+# Return value:
+#   0 on success
+#   1 on missing field
+#   255 on invalid invocation
+#oh_get_folded_multiline_field()
+oh_get_field()
+{
+	case ${#} in
+		1)
+			_control=../control
+			_field=${1}
+			;;
+		2)
+			_control=../${1}.pkg/control
+			_field=${2}
+			;;
+		*)
+			return 255
+			;;
+	esac
+
+	# Force the 'read' utility to read until a line break character.
+	_OLDIFS="${IFS}"
+	IFS='
+'
+
+	# Parse the control file.
+	_value=''
+	while read -r _line; do
+		if [ -z ${_value} ]; then
+			_value=$(echo "${_line}" | sed -n
+			"s/^${_field}:[[:space:]]*\([[:space:]]\)[[:space:]]*$/\\1/p")
+		else
+			if echo "${_line}" | grep '^ ' > /dev/null; then
+				_value="${_value}
+${_line}"
+			else
+				break
+			fi
+		fi
+	done < ${_control}
+
+	# Reset the IFS.
+	IFS="${_OLDIFS}"
+
+	[ -z "${_value}" ] && return 1
+	echo "${_value}"
+	return 0
+}