Add a library of useful shell functions. There are functions for

logging, backslash quoting, and two queue implementations: one entirely
in memory and one using a file.

1 files changed, 329 insertions, 0 deletions

diff --git a/mk/scripts/shell-lib b/mk/scripts/shell-lib
new file mode 100644
index 00000000000..6a7f53aaef4
--- /dev/null
+++ b/mk/scripts/shell-lib
@@ -0,0 +1,329 @@
+# $NetBSD: shell-lib,v 1.1 2004/09/06 18:33:23 jlam Exp $
+#
+# Copyright (c) 2004 The NetBSD Foundation, Inc.
+# All rights reserved.
+#
+# This code is derived from software contributed to The NetBSD Foundation
+# by Johnny C. Lam.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+# 3. All advertising materials mentioning features or use of this software
+#    must display the following acknowledgement:
+#        This product includes software developed by the NetBSD
+#        Foundation, Inc. and its contributors.
+# 4. Neither the name of The NetBSD Foundation nor the names of its
+#    contributors may be used to endorse or promote products derived
+#    from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+######################################################################
+# msg_log logfile msg
+#	Output msg to logfile.  If logfile is "stdout" or "stderr"
+#	then output to there instead.
+######################################################################
+msg_log()
+{
+	: ${echo=echo}
+
+	_msg_log="$1"; shift
+	case $_msg_log in
+	stdout)	$echo "$@" ;;
+	stderr)	$echo "$@" 1>&2 ;;
+	*)	$echo "$@" >> $_msg_log ;;
+	esac
+}
+
+######################################################################
+# die msg
+#	Output $msg to stderr, and exit with a positive error code.
+######################################################################
+die()
+{
+	msg_log stderr "$@"
+	exit 1
+}
+
+######################################################################
+# check_prog var prog ...
+#	If $var is empty or unset, then set it to the path of one of
+#	the program names in the list.
+######################################################################
+check_prog()
+{
+	: ${test=test}
+
+	_ckp_var="$1"; shift
+
+	eval _ckp_tmp=\"\$$_ckp_var\"
+	if $test "x$_ckp_tmp" != "x"; then
+		return 0
+	fi
+
+	for _ckp_prog do
+		_ckp_IFS="${IFS}"; IFS=":"
+		for _ckp_dir in ${PATH}; do
+			if $test -x "$_ckp_dir/$_ckp_prog"; then
+				eval $_ckp_var=\""$_ckp_dir/$_ckp_prog"\"
+				return 1
+			fi
+		done
+		IFS="${_ckp_IFS}"
+	done
+
+	die "$_ckp_var could not be set."
+}
+
+######################################################################
+# shquote arg
+#	Returns a backslashed and quoted version of arg in $shquoted.
+######################################################################
+shquote()
+{
+	: ${echo=echo}
+	: ${sed=sed}
+
+	_shq_arg=$1
+	_shq_sed="$sed -e 1s/^X//"
+	_shq_sed_quote_subst='s/\([\`\"$\\]\)/\\\1/g'
+	case $_shq_arg in
+	*[\`\"\$\\]*)
+		shquoted=`$echo "X$_shq_arg" | $_shq_sed -e "$_shq_sed_quote_subst"`
+		;;
+	*)
+		shquoted="$_shq_arg"
+		;;
+	esac
+	case $shquoted in
+	*[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
+		shquoted="\"$shquoted\""
+		;;
+	esac
+}
+
+######################################################################
+######################################################################
+###
+### Queue routines.  The queue is implemented as a set of variables
+### that is unique to each queue name, thus the use of multiple queues
+### is allowed.
+###
+######################################################################
+######################################################################
+
+######################################################################
+# init_queue name
+#	Initialize the named queue.
+######################################################################
+init_queue()
+{
+	_qname="$1"
+	eval "_q${_qname}head=1111111111"
+	eval "_q${_qname}tail=1111111111"
+}
+
+######################################################################
+# append_queue name item ...
+#	Append items onto the end of the named queue in FIFO order.
+######################################################################
+append_queue()
+{
+	: ${test=test}
+
+	_qname="$1"; shift
+	while $test $# -gt 0; do
+		eval "_qtail=\"\$_q${_qname}tail\""
+		eval "_q${_qname}${_qtail}=\"\${1}\""
+		case $_qtail in
+		*000000000)	_qtail=${_qtail%000000000}1 ;;
+		*)		_qtail=${_qtail}0 ;;
+		esac
+		eval "_q${_qname}tail=\"\${_qtail}\""
+		shift
+	done
+}
+
+######################################################################
+# prepend_queue name item ...
+#	Prepend items to the head of the named queue in LIFO order.
+######################################################################
+prepend_queue()
+{
+	: ${test=test}
+
+	_qname="$1"; shift
+	while $test $# -gt 0; do
+		eval "_qhead=\"\$_q${_qname}head\""
+		case $_qhead in
+		*1)	_qhead=${_qhead%1}000000000 ;;
+		*)	_qhead=${_qhead%0} ;;
+		esac
+		eval "_q${_qname}${_qhead}=\"\${1}\""
+		eval "_q${_qname}head=\"\${_qhead}\""
+		shift
+	done
+}
+
+######################################################################
+# head_queue name var
+#	Return the head of the named queue in $var.
+######################################################################
+head_queue()
+{
+	_qname="$1"; shift
+	eval "_qhead=\"\$_q${_qname}head\""
+	eval "${1}=\"\$_q${_qname}${_qhead}\""
+}
+
+######################################################################
+# pop_queue name var
+#	Pop off the head of the named queue and return it in $var.
+######################################################################
+pop_queue()
+{
+	_qname="$1"; shift
+	head_queue $_qname $1
+	case $_qhead in
+	*000000000)	_qhead=${_qhead%000000000}1 ;;
+	*)		_qhead=${_qhead}0 ;;
+	esac
+	eval "_q${_qname}head=\"\${_qhead}\""
+}
+
+######################################################################
+# queue_is_empty name
+#	Return 0 if the named queue is empty and 1 otherwise.
+######################################################################
+queue_is_empty()
+{
+	: ${test=test}
+
+	_qname="$1"
+	eval "_qhead=\"\$_q${_qname}head\""
+	eval "_qtail=\"\$_q${_qname}tail\""
+	$test "$_qhead" = "$_qtail"
+	return $?
+}
+
+######################################################################
+######################################################################
+###
+### File queue routines.  The file queue is implemented as a file
+### whose lines represent the queue elements.  The file queue name
+### is simply the file used for the queue, thus the use of multiple
+### queues is allowed.
+###
+######################################################################
+######################################################################
+
+######################################################################
+# init_fqueue name
+#	Initialize the named file queue.
+######################################################################
+init_fqueue()
+{
+	_fqname="$1"
+	: > "$_fqname"
+}
+
+######################################################################
+# append_fqueue name item ...
+#	Append items onto the end of the named file queue in FIFO order.
+######################################################################
+append_fqueue()
+{
+	: ${echo=echo}
+	: ${test=test}
+
+	_fqname="$1"; shift
+	while $test $# -gt 0; do
+		$echo "$1" >> "$_fqname"
+		shift
+	done
+}
+
+######################################################################
+# prepend_fqueue name item ...
+#	Prepend items to the head of the named file queue in LIFO order.
+######################################################################
+prepend_fqueue()
+{
+	: ${cat=cat}
+	: ${echo=echo}
+	: ${mv=mv}
+
+	_fqname="$1"; shift
+	_fqtmpfile="$_fqname.$$"
+	init_queue _fqtmpqueue
+	prepend_queue _fqtmpqueue "$@"
+	while ! queue_is_empty _fqtmpqueue; do
+		pop_queue _fqtmpqueue _fqelt
+		$echo "$_fqelt" >> "$_fqtmpfile"
+	done
+	$cat "$_fqname" >> "$_fqtmpfile"
+	$mv -f "$_fqtmpfile" "$_fqname"
+}
+
+######################################################################
+# head_fqueue name var
+#	Return the head of the named file queue in $var.
+######################################################################
+head_fqueue()
+{
+	: ${head=head}
+
+	_fqname="$1"; shift
+	_tmp=`$head -n 1 "$_fqname"`
+	eval "${1}=\"\$_tmp\""
+}
+
+######################################################################
+# pop_fqueue name var
+#	Pop off the head of the named file queue and return it in $var.
+######################################################################
+pop_fqueue()
+{
+	: ${mv=mv}
+	: ${sed=sed}
+
+	_fqname="$1"; shift
+	_fqtmpfile="$_fqname.$$"
+	head_fqueue "$_fqname" $1
+	$sed "1,1d" "$_fqname" >> "$_fqtmpfile"
+	$mv -f "$_fqtmpfile" "$_fqname"
+}
+
+######################################################################
+# fqueue_is_empty name
+#	Return 0 if the named file queue is empty and >0 otherwise.
+######################################################################
+fqueue_is_empty()
+{
+	: ${test=test}
+	: ${wc=wc}
+
+	_fqname="$1"
+	if $test -f "$_fqname"; then
+		_fqlines=`$wc -l < "$_fqname"`
+		return $_fqlines
+	else
+		return 1
+	fi
+}