Refactor the build system. Avoid recursive make.

This looks like a lot, but more things should "just work".

We have `make dist` now!

8 files changed, 373 insertions, 326 deletions

diff --git a/src/lib/Makefile b/src/lib/Makefile
index 97b30eb..f9ec1e8 100644
--- a/src/lib/Makefile
+++ b/src/lib/Makefile
@@ -1,17 +1,17 @@
-copy_files = common.sh.in
-libexecs = $(filter-out librelib,$(progs))
-# include common.sh in libs explicitly, because it might not exist yet
-# when the wildcard is performed
-libs = $(sort $(wildcard *.sh) common.sh conf.sh)
+include $(dir $(lastword $(MAKEFILE_LIST)))/../../config.mk
+include $(topsrcdir)/automake.head.mk
 
-include ../../common.mk
+install-libs += common.sh conf.sh
+devtools-files = common.sh.in
 
 # Build ##############################################################
 
-common.sh: %: %.in %.top Makefile
-	@echo "GEN $@"
+$(outdir)/conf.sh: $(var)sysconfdir $(var)pkgconfdir
+
+$(outdir)/common.sh: $(outdir)/%: $(srcdir)/%.in $(srcdir)/%.head $(srcdir)/%.tail $(outdir)/Makefile
+	@echo "OUT $@"
 	@{ \
-	cat '$*.top' && \
+	cat '$(<D)/$*.head' && \
 	echo && \
 	sed -r \
 		-e '/encoding problem/d;/LANG=/d' \
@@ -19,21 +19,27 @@ common.sh: %: %.in %.top Makefile
 		-e 's/gettext /_l _ /g' \
 		-e "s/^(\s+)(msg|error) '/\1_l \2 '/" \
 		-e 's|lock\(\)\s*\{|lock()\n{|' \
-		'$*.in' && \
+		'$(<D)/$*.in' && \
 	echo && \
-	cat '$*.bottom' && \
+	cat '$(<D)/$*.tail' && \
 	:; } > '$@'
 
 # Translate ##########################################################
 
-LIBREXGETTEXT_FLAGS += --simple=_l:2
-
-libreblacklist.pot: libreblacklist librexgettext
-	{ \
+$(outdir)/blacklist.sh.pot: $(srcdir)/blacklist.sh $(srcdir)/librexgettext
+	@echo "OUT $@"
+	@{ \
 		sed -n '/^# Usage:/,/()/{ /^#/ { =; p; } }' $< | \
 			sed -r -e 's/^# (.*)/msgid "\1"\nmsgstr ""\n/' \
-			       -e 's/^[0-9]*$$/#. embedded usage text\n#: $<:&/'; \
-		./librexgettext $<; \
-	} | $(pofmt) > $@
+			       -e 's/^[0-9]*$$/#. embedded usage text\n#: $<:&/' && \
+		$(<D)/librexgettext --simple=_l:2 $< && \
+	:; } | $(pofmt) > $@
+$(outdir)/common.sh.pot    : LIBREXGETTEXT_FLAGS += --simple=_l:2
+$(outdir)/conf.sh.pot      : LIBREXGETTEXT_FLAGS += --simple=_l:2
+$(outdir)/librelib.pot     : LIBREXGETTEXT_FLAGS += --simple=_l:2
+$(outdir)/messages.sh.pot  : LIBREXGETTEXT_FLAGS += --simple=_l:2
+$(outdir)/librexgettext.pot: LIBREXGETTEXT_FLAGS += --simple=errusage
+
+######################################################################
 
-librexgettext.pot: LIBREXGETTEXT_FLAGS += --simple=errusage
+include $(topsrcdir)/automake.tail.mk
diff --git a/src/lib/blacklist.sh b/src/lib/blacklist.sh
new file mode 100644
index 0000000..0a3cc39
--- /dev/null
+++ b/src/lib/blacklist.sh
@@ -0,0 +1,96 @@
+#!/usr/bin/env bash
+# This may be included with or without `set -euE`
+
+# Copyright (C) 2013-2014, 2016 Luke Shumaker <lukeshu@sbcglobal.net>
+#
+# License: GNU GPLv2+
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# make sure XDG_CACHE_HOME is set
+. "$(librelib conf)"
+
+# Usage: blacklist-normalize <$file
+# Normalizes the syntax of the blacklist on stdin.
+blacklist-normalize() {
+	sed -e '/^#/d' -e 's/^[^:]*$/&::/' -e 's/^[^:]*:[^:]*$/&:/'
+}
+
+# Usage: blacklist-cat
+# Prints the blacklist.
+# Uses the cache, but downloads it if it doesn't exist.  Also normalizes the blacklist for easier parsing.
+blacklist-cat() {
+	local file="$XDG_CACHE_HOME/libretools/blacklist.txt"
+	if ! [[ -e $file ]]; then
+		# exit on failure, whether set -e or not
+		blacklist-update || return $?
+	fi
+	blacklist-normalize < "$file"
+}
+
+# Usage: blacklist-update
+# Updates (or creates) the cached copy of the blacklist.
+blacklist-update() (
+	. libremessages
+	load_files libretools || return 1
+	check_vars libretools BLACKLIST || return 1
+
+	local remote_blacklist="$BLACKLIST"
+	local local_blacklist="$XDG_CACHE_HOME/libretools/blacklist.txt"
+
+	_l stat_busy "Downloading blacklist of proprietary software packages"
+
+	mkdir -p "${local_blacklist%/*}"
+	if wget -N -q -O "${local_blacklist}.part" "$remote_blacklist" 2>/dev/null; then
+		stat_done
+		mv -f "${local_blacklist}.part" "$local_blacklist"
+	else
+		stat_done
+		rm "${local_blacklist}.part"
+		if [[ -e "$local_blacklist" ]]; then
+			_l warning "Using local copy of blacklist"
+		else
+			_l error "Download failed, exiting"
+			return 1
+		fi
+
+	fi
+)
+
+# Usage: blacklist-cat | blacklist-lookup $pkgname
+# Filters to obtain the line for $pkgname from the blacklist on stdin.
+# Exits successfully whether a line is found or not.
+blacklist-lookup() {
+	local pkg=$1
+	# we accept that $pkg contains no regex-nes
+	blacklist-normalize | grep "^$pkg:" || true
+}
+
+# Usage: blacklist-cat | blacklist-get-pkg
+# Prints only the package name field of the blacklist line(s) on stdin.
+blacklist-get-pkg() {
+	blacklist-normalize | cut -d: -f1
+}
+
+# Usage: blacklist-cat | blacklist-get-rep
+# Prints only the replacement package field of the blacklist line(s) on stdin.
+blacklist-get-rep() {
+	blacklist-normalize | cut -d: -f2
+}
+
+# Usage: blacklist-cat | blacklist-get-reason
+# Prints only the reason field of the blacklist line(s) on stdin.
+blacklist-get-reason() {
+	blacklist-normalize | cut -d: -f3-
+}
diff --git a/src/lib/common.sh.top b/src/lib/common.sh.head
index 23bfeb8..23bfeb8 100644
--- a/src/lib/common.sh.top
+++ b/src/lib/common.sh.head
diff --git a/src/lib/common.sh.bottom b/src/lib/common.sh.tail
index e133fad..e133fad 100644
--- a/src/lib/common.sh.bottom
+++ b/src/lib/common.sh.tail
diff --git a/src/lib/libreblacklist b/src/lib/libreblacklist
index 1e5a467..6c354fe 100755
--- a/src/lib/libreblacklist
+++ b/src/lib/libreblacklist
@@ -1,8 +1,5 @@
 #!/usr/bin/env bash
-# This may be included with or without `set -euE`
-# When run directly, it does `set -euE`
-
-# Copyright (C) 2013-2014 Luke Shumaker <lukeshu@sbcglobal.net>
+# Copyright (C) 2013-2014, 2016 Luke Shumaker <lukeshu@sbcglobal.net>
 #
 # License: GNU GPLv2+
 #
@@ -19,88 +16,17 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# make sure XDG_CACHE_HOME is set
-. "$(librelib conf)"
-
-# Usage: blacklist-normalize <$file
-# Normalizes the syntax of the blacklist on stdin.
-blacklist-normalize() {
-	sed -e '/^#/d' -e 's/^[^:]*$/&::/' -e 's/^[^:]*:[^:]*$/&:/'
-}
-
-# Usage: blacklist-cat
-# Prints the blacklist.
-# Uses the cache, but downloads it if it doesn't exist.  Also normalizes the blacklist for easier parsing.
-blacklist-cat() {
-	local file="$XDG_CACHE_HOME/libretools/blacklist.txt"
-	if ! [[ -e $file ]]; then
-		# exit on failure, whether set -e or not
-		blacklist-update || return $?
-	fi
-	blacklist-normalize < "$file"
-}
-
-# Usage: blacklist-update
-# Updates (or creates) the cached copy of the blacklist.
-blacklist-update() (
-	. libremessages
-	load_files libretools || return 1
-	check_vars libretools BLACKLIST || return 1
-
-	local remote_blacklist="$BLACKLIST"
-	local local_blacklist="$XDG_CACHE_HOME/libretools/blacklist.txt"
-
-	_l stat_busy "Downloading blacklist of proprietary software packages"
-
-	mkdir -p "${local_blacklist%/*}"
-	if wget -N -q -O "${local_blacklist}.part" "$remote_blacklist" 2>/dev/null; then
-		stat_done
-		mv -f "${local_blacklist}.part" "$local_blacklist"
-	else
-		stat_done
-		rm "${local_blacklist}.part"
-		if [[ -e "$local_blacklist" ]]; then
-			_l warning "Using local copy of blacklist"
-		else
-			_l error "Download failed, exiting"
-			return 1
-		fi
-
-	fi
-)
-
-# Usage: blacklist-cat | blacklist-lookup $pkgname
-# Filters to obtain the line for $pkgname from the blacklist on stdin.
-# Exits successfully whether a line is found or not.
-blacklist-lookup() {
-	local pkg=$1
-	# we accept that $pkg contains no regex-nes
-	blacklist-normalize | grep "^$pkg:" || true
-}
-
-# Usage: blacklist-cat | blacklist-get-pkg
-# Prints only the package name field of the blacklist line(s) on stdin.
-blacklist-get-pkg() {
-	blacklist-normalize | cut -d: -f1
-}
-
-# Usage: blacklist-cat | blacklist-get-rep
-# Prints only the replacement package field of the blacklist line(s) on stdin.
-blacklist-get-rep() {
-	blacklist-normalize | cut -d: -f2
-}
+if [[ "${0##*/}" != libreblacklist ]]; then
+	. "$(librelib blacklist)"
+else
+	set -euE
 
-# Usage: blacklist-cat | blacklist-get-reason
-# Prints only the reason field of the blacklist line(s) on stdin.
-blacklist-get-reason() {
-	blacklist-normalize | cut -d: -f3-
-}
+	lib_file="$(librelib blacklist)"
+	. "$lib_file"
 
-if [[ "${0##*/}" == libreblacklist ]]; then
-	set -euE
 	usage-outside() {
-		sed -n '/^# Usage:/,/()/p' "$0" |
-		tr '\n' '\r' | sed 's/\s*()\s*[{(]/\n/g'
+		sed -n '/^# Usage:/,/()/p' "$lib_file" |
+		    tr '\n' '\r' | sed 's/\s*()\s*[{(]/\n/g'
 	}
 	# The output format of this is:
 	#  - The first line is "Usage:"
@@ -110,6 +36,7 @@ if [[ "${0##*/}" == libreblacklist ]]; then
 	usage-inside() {
 		sed 's/\r/\n/g'<<<"$1"|sed -e '/^$/d' -e 's/^# //'
 	}
+
 	usage() {
 		export TEXTDOMAIN='librelib'
 		export TEXTDOMAINDIR='/usr/share/locale'
@@ -120,33 +47,37 @@ if [[ "${0##*/}" == libreblacklist ]]; then
 			echo
 			print "Commands:"
 			usage-outside | while read -r sec; do sec="$(usage-inside "$sec")"
-				cmd=$(<<<"$sec" sed -n '$s/^blacklist-//p')
-				desc="$(_ "$(sed -n 2p <<<"$sec")")"
-				flag "$cmd" "${desc//blacklist-/${0##*/} }"
+							      cmd=$(<<<"$sec" sed -n '$s/^blacklist-//p')
+							      desc="$(_ "$(sed -n 2p <<<"$sec")")"
+							      flag "$cmd" "${desc//blacklist-/${0##*/} }"
 			done
 		else
 			usage-outside | while read -r sec; do sec="$(usage-inside "$sec")"
-				cmd=$(<<<"$sec" sed -n '$s/^blacklist-//p')
-				if [[ "$cmd" == "$1" ]]; then
-					<<<"$sec" sed '$d' |
-					while read -r line; do print "$line"; done |
-					sed "s/blacklist-/${0##*/} /g" |
-					fmt -us
-					return 0
-				fi
+							      cmd=$(<<<"$sec" sed -n '$s/^blacklist-//p')
+							      if [[ "$cmd" == "$1" ]]; then
+								      <<<"$sec" sed '$d' |
+									  while read -r line; do print "$line"; done |
+									  sed "s/blacklist-/${0##*/} /g" |
+									  fmt -us
+								      return 0
+							      fi
 			done
 		fi
 	}
 
-	if [[ $# -eq 0 ]]; then
-		usage >&2
-		exit 1
-	fi
-	_blacklist_cmd=$1
-	shift
-	if [[ $_blacklist_cmd == -h ]]; then
-		usage "$@"
-	else
-		"blacklist-$_blacklist_cmd" "$@"
-	fi
+	main() {
+		if [[ $# -eq 0 ]]; then
+			usage >&2
+			exit 1
+		fi
+		_blacklist_cmd=$1
+		shift
+		if [[ $_blacklist_cmd == -h ]]; then
+			usage "$@"
+		else
+			"blacklist-$_blacklist_cmd" "$@"
+		fi
+	}
+
+	main "$@"
 fi
diff --git a/src/lib/librelib.7.ronn b/src/lib/librelib.7.ronn
index 31fb65f..33b0c55 100644
--- a/src/lib/librelib.7.ronn
+++ b/src/lib/librelib.7.ronn
@@ -11,8 +11,7 @@ There are three parts to librelib:
 
  1. The `librelib`(1) executable.
  2. The non-executable libraries installed in `/usr/lib/libretools`
- 3. The executable libraries installed in both `/usr/bin` and
-    `/usr/lib/libretools`.
+ 3. The executable libraries installed in `/usr/bin`
 
 The `librelib` executable isn't very exciting, it just finds the
 libraries installed in `/usr/lib/libretools`.  Think of it as a sort
diff --git a/src/lib/libremessages b/src/lib/libremessages
index 528d9b6..647204a 100755
--- a/src/lib/libremessages
+++ b/src/lib/libremessages
@@ -1,19 +1,5 @@
 #!/usr/bin/env bash
-# This may be included with or without `set -euE`
-# When run directly, it does `set -euE`
-
-# Copyright (C) 2011 Joshua Ismael Haase Hernández (xihh) <hahj87@gmail.com>
-# Copyright (C) 2012 Nicolás Reynolds <fauno@parabola.nu>
-# Copyright (C) 2012-2014 Luke Shumaker <lukeshu@sbcglobal.net>
-
-# For just the setup_traps() function:
-#   Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>
-#   Copyright (C) 2006-2010 Pacman Development Team <pacman-dev@archlinux.org>
-#   Copyright (C) 2005 Aurelien Foret <orelien@chez.com>
-#   Copyright (C) 2005 Christian Hamar <krics@linuxforum.hu>
-#   Copyright (C) 2006 Alex Smith <alex@alex-smith.me.uk>
-#   Copyright (C) 2006 Andras Voroskoi <voroskoi@frugalware.org>
-#   Copyright (C) 2006 Miklos Vajna <vmiklos@frugalware.org>
+# Copyright (C) 2012-2014, 2016 Luke Shumaker <lukeshu@sbcglobal.net>
 #
 # License: GNU GPLv2+
 #
@@ -30,189 +16,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-################################################################################
-# Inherit most functions from devtools                                         #
-################################################################################
-
-. "$(librelib common.sh)"
-
-################################################################################
-# Own functions                                                                #
-################################################################################
-
-# Usage: panic
-#
-# For programming errors, bails immediately with little fanfare.
-panic() {
-	echo "$(_l _ 'panic: malformed call to internal function')" >&2
-	exit 1
-}
-
-# Usage: print MESG [ARGS...]
-#
-# Like printf, but gettext-aware, and prints a trailing newline
-print() {
-	[[ $# -ge 1 ]] || panic
-	local mesg="$(_ "$1")"
-	shift
-	printf -- "$mesg\n" "$@"
-}
-
-# Usage: whitespace_collapse <<<STRING
-#
-# Collapses whitespace on stadard I/O, similar to HTML whitespace
-# collapsing, with the exception that it puts two spaces between
-# sentences.  It considers newline, tab, and space to be whitespace.
-whitespace_collapse() {
-	[[ $# == 0 ]] || panic
-
-	tr '\n' '\r' | sed -r \
-			   -e 's/\r/  /g' -e 's/\t/ /g' \
-			   -e 's/(^|[^.!? ]) +/\1 /g' -e 's/([.!?])  +/\1  /g'
-}
-
-
-# Usage: prose MESG [ARGS...]
-#
-# Do HTML-style whitespace collapsing on the first argument, translate
-# it (gettext), then word-wrap it to 75 columns.  This is useful for
-# printing a paragraph of prose in --help text.
-prose() {
-	[[ $# -ge 1 ]] || panic
-	local mesg="$(_ "$(whitespace_collapse <<<"$1")")"; shift
-	printf -- "$mesg" "$@" | fmt -u
-}
-
-# Usage: bullet MESG [ARGS...]
-# Like prose, but print a bullet "-" before the first line, and indent the
-# remaining lines.
-bullet() {
-	[[ $# -ge 1 ]] || panic
-	local mesg="$(_ "$(whitespace_collapse <<<"$1")")"; shift
-	# Wrap the text to 71 columns; 75 (the default) minus a 4 column indent
-	printf -- "$mesg" "$@" | fmt -u -w 71 | sed -e '1s/^/  - /' -e '2,$s/^/    /'
-}
-
-# Usage: flag FLAG DESCRIPTION [FLAG2 DESCRIPTION2...]
-#
-# Print a flag and description formatted for --help text.
-#
-#   ex: flag '-C <FILE>' 'Use this file instead of pacman.conf'
-#
-# The description is fed through gettext, the flag is not, so if part
-# of the flag needs to be translated, you must do that yourself:
-#
-#   ex: flag "-C <$(_ FILE)>" 'Use this file instead of pacman.conf'
-#
-# If you want to line-break the description in the source, so it isn't
-# crazy-long, feel free, it is reflowed/wrapped the same way as prose
-# and bullet.  If you pass in multiple flag/description pairs at once,
-# the descriptions are all alligned together.
-flag() {
-	[[ $# == $(($#/2*2)) ]] || panic
-	local args=("$@")
-
-	declare -i flaglen=0
-	while [[ $# -gt 0 ]]; do
-		if [[ $1 == *: ]]; then
-			shift 1
-		else
-			if [[ ${#1} -gt $flaglen ]]; then
-				flaglen=${#1}
-			fi
-			shift 2
-		fi
-	done
-	set -- "${args[@]}"
-
-	# Unless the $flaglen is extra-wide, the $desc should start at
-	# column 16 (that is two literal-tabs).  If $flaglen is wide,
-	# this should be increased in increments of 8 (that is, a
-	# literal-tab).  Everything should be wrapped to 75 columns.
-
-	# The printf-format we use has 4 spaces built into it (two at
-	# the beginning, and two for a seperator).  Therefore, the
-	# default indent is 16-4=12 columns.  And the width left for
-	# $desc is (75-4)-indent = 71-indent.
-
-	declare -i indent=12
-	while [[ $indent -lt $flaglen ]]; do
-		indent+=8
-	done
-	local fmt2 fmt1
-	fmt2="  %-${indent}s  %s\n"
-	printf -v fmt1 "  %-${indent}s  %%s\n" ''
-
-	while [[ $# -gt 0 ]]; do
-		if [[ $1 == *: ]]; then
-			printf -- ' %s\n' "$(_ "$1")"
-			shift
-		else
-			local flag=$1
-			local desc="$(_ "$(whitespace_collapse <<<"$2")")"
-			shift 2
-
-			local lines
-			IFS=$'\n' lines=($(fmt -u -w $((71-indent)) <<<"$desc"))
-			printf -- "$fmt2" "$flag" "${lines[0]}"
-			[[ ${#lines[@]} -lt 2 ]] || printf -- "$fmt1" "${lines[@]:1}"
-		fi
-	done
-}
-
-# Usage: term_title MESG [ARGS...]
-#
-# Sets the terminal title.
-term_title() {
-	[[ $# -ge 1 ]] || panic
-	local fmt=''
-	case "$TERM" in
-		screen|tmux) fmt='\ek%s\e\\';;
-		xterm*|rxvt*) fmt='\e]0;%s\a';;
-	esac
-	printf "$fmt" "$(printf -- "$@")"
-}
-
-# Usage: setup_traps [handler]
-#
-# Sets up traps on TERM, HUP, QUIT and INT signals, as well as the ERR
-# event, similar to makepkg.
-#
-# If `handler` is specified, instead of using the default handler
-# (which is good for most purposes), it will call the command handler
-# with the arguments:
-#
-#   ${handler} SIGNAL_NAME MESSAGE_FMT [MESSAGE_PARAMS...]
-#
-# where MESSAGE_* are printf-like stuff.
-#
-# This function is based on code from pacman:makepkg
-setup_traps() {
-	[[ $# -le 1 ]] || panic
-	if [[ $# == 1 ]]; then
-		eval "_libremessages_trap_exit() { $1 \"\$@\"; }"
-	else
-		_libremessages_trap_exit() {
-			local signal=$1; shift
-			echo
-			error "$@"
-			trap -- "$signal"
-			kill "-$signal" "$$"
-		}
-	fi
-	set -E
-	for signal in TERM HUP QUIT; do
-		trap "_libremessages_trap_exit $signal '%s signal caught. Exiting...' $signal" $signal
-	done
-	trap '_libremessages_trap_exit INT "Aborted by user! Exiting..."' INT
-	trap '_libremessages_trap_exit USR1 "An unknown error has occurred. Exiting..."' ERR
-}
-
-################################################################################
-# Run one of the defined functions if invoked directly                         #
-################################################################################
-
-if [[ "${0##*/}" == libremessages ]]; then
-	set -euE
-	"$@"
+if [[ "${0##*/}" != libremessages ]]; then
+        . "$(librelib messages)"
+else
+        set -euE
+        . "$(librelib messages)"
+        "$@"
 fi
diff --git a/src/lib/messages.sh b/src/lib/messages.sh
new file mode 100644
index 0000000..4b4897e
--- /dev/null
+++ b/src/lib/messages.sh
@@ -0,0 +1,208 @@
+#!/usr/bin/env bash
+# This may be included with or without `set -euE`
+
+# Copyright (C) 2011 Joshua Ismael Haase Hernández (xihh) <hahj87@gmail.com>
+# Copyright (C) 2012 Nicolás Reynolds <fauno@parabola.nu>
+# Copyright (C) 2012-2014, 2016 Luke Shumaker <lukeshu@sbcglobal.net>
+#
+# For just the setup_traps() function:
+#   Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>
+#   Copyright (C) 2006-2010 Pacman Development Team <pacman-dev@archlinux.org>
+#   Copyright (C) 2005 Aurelien Foret <orelien@chez.com>
+#   Copyright (C) 2005 Christian Hamar <krics@linuxforum.hu>
+#   Copyright (C) 2006 Alex Smith <alex@alex-smith.me.uk>
+#   Copyright (C) 2006 Andras Voroskoi <voroskoi@frugalware.org>
+#   Copyright (C) 2006 Miklos Vajna <vmiklos@frugalware.org>
+#
+# License: GNU GPLv2+
+#
+# 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 2 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/>.
+
+################################################################################
+# Inherit most functions from devtools                                         #
+################################################################################
+
+. "$(librelib common.sh)"
+
+################################################################################
+# Own functions                                                                #
+################################################################################
+
+# Usage: panic
+#
+# For programming errors, bails immediately with little fanfare.
+panic() {
+	echo "$(_l _ 'panic: malformed call to internal function')" >&2
+	exit 1
+}
+
+# Usage: print MESG [ARGS...]
+#
+# Like printf, but gettext-aware, and prints a trailing newline
+print() {
+	[[ $# -ge 1 ]] || panic
+	local mesg="$(_ "$1")"
+	shift
+	printf -- "$mesg\n" "$@"
+}
+
+# Usage: whitespace_collapse <<<STRING
+#
+# Collapses whitespace on stadard I/O, similar to HTML whitespace
+# collapsing, with the exception that it puts two spaces between
+# sentences.  It considers newline, tab, and space to be whitespace.
+whitespace_collapse() {
+	[[ $# == 0 ]] || panic
+
+	tr '\n' '\r' | sed -r \
+			   -e 's/\r/  /g' -e 's/\t/ /g' \
+			   -e 's/(^|[^.!? ]) +/\1 /g' -e 's/([.!?])  +/\1  /g'
+}
+
+
+# Usage: prose MESG [ARGS...]
+#
+# Do HTML-style whitespace collapsing on the first argument, translate
+# it (gettext), then word-wrap it to 75 columns.  This is useful for
+# printing a paragraph of prose in --help text.
+prose() {
+	[[ $# -ge 1 ]] || panic
+	local mesg="$(_ "$(whitespace_collapse <<<"$1")")"; shift
+	printf -- "$mesg" "$@" | fmt -u
+}
+
+# Usage: bullet MESG [ARGS...]
+# Like prose, but print a bullet "-" before the first line, and indent the
+# remaining lines.
+bullet() {
+	[[ $# -ge 1 ]] || panic
+	local mesg="$(_ "$(whitespace_collapse <<<"$1")")"; shift
+	# Wrap the text to 71 columns; 75 (the default) minus a 4 column indent
+	printf -- "$mesg" "$@" | fmt -u -w 71 | sed -e '1s/^/  - /' -e '2,$s/^/    /'
+}
+
+# Usage: flag FLAG DESCRIPTION [FLAG2 DESCRIPTION2...]
+#
+# Print a flag and description formatted for --help text.
+#
+#   ex: flag '-C <FILE>' 'Use this file instead of pacman.conf'
+#
+# The description is fed through gettext, the flag is not, so if part
+# of the flag needs to be translated, you must do that yourself:
+#
+#   ex: flag "-C <$(_ FILE)>" 'Use this file instead of pacman.conf'
+#
+# If you want to line-break the description in the source, so it isn't
+# crazy-long, feel free, it is reflowed/wrapped the same way as prose
+# and bullet.  If you pass in multiple flag/description pairs at once,
+# the descriptions are all alligned together.
+flag() {
+	[[ $# == $(($#/2*2)) ]] || panic
+	local args=("$@")
+
+	declare -i flaglen=0
+	while [[ $# -gt 0 ]]; do
+		if [[ $1 == *: ]]; then
+			shift 1
+		else
+			if [[ ${#1} -gt $flaglen ]]; then
+				flaglen=${#1}
+			fi
+			shift 2
+		fi
+	done
+	set -- "${args[@]}"
+
+	# Unless the $flaglen is extra-wide, the $desc should start at
+	# column 16 (that is two literal-tabs).  If $flaglen is wide,
+	# this should be increased in increments of 8 (that is, a
+	# literal-tab).  Everything should be wrapped to 75 columns.
+
+	# The printf-format we use has 4 spaces built into it (two at
+	# the beginning, and two for a seperator).  Therefore, the
+	# default indent is 16-4=12 columns.  And the width left for
+	# $desc is (75-4)-indent = 71-indent.
+
+	declare -i indent=12
+	while [[ $indent -lt $flaglen ]]; do
+		indent+=8
+	done
+	local fmt2 fmt1
+	fmt2="  %-${indent}s  %s\n"
+	printf -v fmt1 "  %-${indent}s  %%s\n" ''
+
+	while [[ $# -gt 0 ]]; do
+		if [[ $1 == *: ]]; then
+			printf -- ' %s\n' "$(_ "$1")"
+			shift
+		else
+			local flag=$1
+			local desc="$(_ "$(whitespace_collapse <<<"$2")")"
+			shift 2
+
+			local lines
+			IFS=$'\n' lines=($(fmt -u -w $((71-indent)) <<<"$desc"))
+			printf -- "$fmt2" "$flag" "${lines[0]}"
+			[[ ${#lines[@]} -lt 2 ]] || printf -- "$fmt1" "${lines[@]:1}"
+		fi
+	done
+}
+
+# Usage: term_title MESG [ARGS...]
+#
+# Sets the terminal title.
+term_title() {
+	[[ $# -ge 1 ]] || panic
+	local fmt=''
+	case "$TERM" in
+		screen|tmux) fmt='\ek%s\e\\';;
+		xterm*|rxvt*) fmt='\e]0;%s\a';;
+	esac
+	printf "$fmt" "$(printf -- "$@")"
+}
+
+# Usage: setup_traps [handler]
+#
+# Sets up traps on TERM, HUP, QUIT and INT signals, as well as the ERR
+# event, similar to makepkg.
+#
+# If `handler` is specified, instead of using the default handler
+# (which is good for most purposes), it will call the command handler
+# with the arguments:
+#
+#   ${handler} SIGNAL_NAME MESSAGE_FMT [MESSAGE_PARAMS...]
+#
+# where MESSAGE_* are printf-like stuff.
+#
+# This function is based on code from pacman:makepkg
+setup_traps() {
+	[[ $# -le 1 ]] || panic
+	if [[ $# == 1 ]]; then
+		eval "_libremessages_trap_exit() { $1 \"\$@\"; }"
+	else
+		_libremessages_trap_exit() {
+			local signal=$1; shift
+			echo
+			error "$@"
+			trap -- "$signal"
+			kill "-$signal" "$$"
+		}
+	fi
+	set -E
+	for signal in TERM HUP QUIT; do
+		trap "_libremessages_trap_exit $signal '%s signal caught. Exiting...' $signal" $signal
+	done
+	trap '_libremessages_trap_exit INT "Aborted by user! Exiting..."' INT
+	trap '_libremessages_trap_exit USR1 "An unknown error has occurred. Exiting..."' ERR
+}