Build: Add support for translated man pages using po4a.

The dependency on po4a is optional. It's never required to install
the translated man pages when xz is built from a release tarball.
If po4a is missing when building from xz.git, the translated man
pages won't be generated but otherwise the build will work normally.

The translations are only updated automatically by autogen.sh and
by "make mydist". This makes it easy to keep po4a as an optional
dependency and ensures that I won't forget to put updated
translations to a release tarball.

The translated man pages aren't installed if --disable-nls is used.

The installation of translated man pages abuses Automake internals
by calling "install-man" with redefined dist_man_MANS and man_MANS.
This makes the hairy script code slightly less hairy. If it breaks
some day, this code needs to be fixed; don't blame Automake developers.

Also, this adds more quotes to the existing shell script code in
the Makefile.am "-hook"s.

8 files changed, 197 insertions, 45 deletions

diff --git a/Makefile.am b/Makefile.am
index 16db5142..3a634991 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -47,6 +47,7 @@ dist_examplesold_DATA = \
 endif
 
 EXTRA_DIST = \
+	po4a \
 	extra \
 	dos \
 	windows \
@@ -99,8 +100,11 @@ dist-hook:
 	fi
 
 # This works with GNU tar and gives cleaner package than normal 'make dist'.
+# This also ensures that the man page translations are up to date (dist-hook
+# would be too late for that).
 mydist:
 	sh "$(srcdir)/src/liblzma/validate_map.sh"
+	cd "$(srcdir)/po4a" && sh update-po
 	VERSION=$(VERSION); \
 	if test -d "$(srcdir)/.git" && type git > /dev/null 2>&1; then \
 		SNAPSHOT=`cd "$(srcdir)" && git describe --abbrev=4 | cut -b2-`; \
diff --git a/autogen.sh b/autogen.sh
index f0195eca..fb8d983f 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -9,14 +9,16 @@
 #
 ###############################################################################
 
-# The result of using "autoreconf -fi" should be identical to using this
-# script. I'm leaving this script here just in case someone finds it useful.
-
 set -e -x
 
+# The following six lines are almost identical to "autoreconf -fi" but faster.
 ${AUTOPOINT:-autopoint} -f
 ${LIBTOOLIZE:-libtoolize} -c -f || glibtoolize -c -f
 ${ACLOCAL:-aclocal} -I m4
 ${AUTOCONF:-autoconf}
 ${AUTOHEADER:-autoheader}
 ${AUTOMAKE:-automake} -acf --foreign
+
+# Generate the translated man pages if the "po4a" tool is available.
+# This is *NOT* done by "autoreconf -fi" or when "make" is run.
+cd po4a && sh update-po
diff --git a/po4a/.gitignore b/po4a/.gitignore
new file mode 100644
index 00000000..5bcfa04b
--- /dev/null
+++ b/po4a/.gitignore
@@ -0,0 +1,2 @@
+/man
+/xz-man.pot
diff --git a/po4a/po4a.conf b/po4a/po4a.conf
new file mode 100644
index 00000000..41a90fc2
--- /dev/null
+++ b/po4a/po4a.conf
@@ -0,0 +1,14 @@
+# To add a new language, add it to po4a_langs and run "update-po"
+# to get a new .po file. After translating the .po file, run
+# "update-po" again to generate the translated man pages.
+
+[po4a_langs]
+[po4a_paths] xz-man.pot $lang:$lang.po
+
+[type: man] ../src/xz/xz.1              $lang:man/$lang/xz.1
+[type: man] ../src/xzdec/xzdec.1        $lang:man/$lang/xzdec.1
+[type: man] ../src/lzmainfo/lzmainfo.1  $lang:man/$lang/lzmainfo.1
+[type: man] ../src/scripts/xzdiff.1     $lang:man/$lang/xzdiff.1
+[type: man] ../src/scripts/xzgrep.1     $lang:man/$lang/xzgrep.1
+[type: man] ../src/scripts/xzless.1     $lang:man/$lang/xzless.1
+[type: man] ../src/scripts/xzmore.1     $lang:man/$lang/xzmore.1
diff --git a/po4a/update-po b/po4a/update-po
new file mode 100755
index 00000000..c07af928
--- /dev/null
+++ b/po4a/update-po
@@ -0,0 +1,45 @@
+#!/bin/sh
+#
+#############################################################################
+#
+# Updates xz-man.pot and the *.po files, and generates translated man pages.
+# These are done using the program po4a. If po4a is missing, it is still
+# possible to build the package without translated man pages.
+#
+#############################################################################
+#
+# Author: Lasse Collin
+#
+# This file has been put into the public domain.
+# You can do whatever you want with this file.
+#
+#############################################################################
+
+if type po4a > /dev/null 2>&1; then
+	:
+else
+	echo "po4a/update-po: The program 'po4a' was not found." >&2
+	echo "po4a/update-po: Translated man pages were not generated." >&2
+	exit 1
+fi
+
+if test ! -f po4a.conf; then
+	cd `dirname "$0"` || exit 1
+	if test ! -f po4a.conf; then
+		echo "update-po: Error: Cannot find po4a.conf." >&2
+		exit 1
+	fi
+fi
+
+PACKAGE_VERSION=`cd .. && sh build-aux/version.sh` || exit 1
+
+# Using --force to get up-to-date version numbers in the output files
+# when nothing else has changed. This makes it slower but it's fine
+# as long as this isn't run every time when "make" is run at the
+# top level directory. (po4a isn't super-fast even without --force).
+set -x
+po4a --force --verbose \
+	--package-name="XZ Utils" \
+	--package-version="$PACKAGE_VERSION" \
+	--copyright-holder="This file is put in the public domain." \
+	po4a.conf
diff --git a/src/scripts/Makefile.am b/src/scripts/Makefile.am
index 29bdbcd7..fe5742d0 100644
--- a/src/scripts/Makefile.am
+++ b/src/scripts/Makefile.am
@@ -25,31 +25,65 @@ links += \
 endif
 
 install-exec-hook:
-	cd $(DESTDIR)$(bindir) && \
+	cd "$(DESTDIR)$(bindir)" && \
 	for pair in $(links); do \
 		target=`echo $$pair | sed 's/-.*$$//' | sed '$(transform)'` && \
 		link=`echo $$pair | sed 's/^.*-//' | sed '$(transform)'` && \
-		rm -f $$link && \
-		$(LN_S) $$target $$link; \
+		rm -f "$$link" && \
+		$(LN_S) "$$target" "$$link"; \
 	done
 
+# The installation of translated man pages abuses Automake internals
+# by calling "install-man" with redefined dist_man_MANS and man_MANS.
+# If this breaks some day, don't blame Automake developers.
 install-data-hook:
-	cd $(DESTDIR)$(mandir)/man1 && \
-	for pair in $(links); do \
-		target=`echo $$pair | sed 's/-.*$$//' | sed '$(transform)'` && \
-		link=`echo $$pair | sed 's/^.*-//' | sed '$(transform)'` && \
-		rm -f $$link.1 && \
-		$(LN_S) $$target.1 $$link.1; \
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
+	for lang in $$languages; do \
+		mans= ; \
+		for man in $(dist_man_MANS); do \
+			man="$(top_srcdir)/po4a/man/$$lang/$$man" ; \
+			if test -f "$$man"; then \
+				mans="$$mans $$man"; \
+			fi; \
+		done; \
+		$(MAKE) dist_man_MANS="$$mans" man_MANS= \
+				mandir="$(mandir)/$$lang" install-man; \
+	done; \
+	for lang in . $$languages; do \
+		for pair in $(links); do \
+			target=`echo $$pair | sed 's/-.*$$//' \
+					| sed '$(transform)'` && \
+			link=`echo $$pair | sed 's/^.*-//' \
+					| sed '$(transform)'` && \
+			man1dir="$(DESTDIR)$(mandir)/$$lang/man1" && \
+			if test -f "$$man1dir/$$target.1"; then ( \
+				cd "$$man1dir" && \
+				rm -f "$$link.1" && \
+				$(LN_S) "$$target.1" "$$link.1" \
+			); fi; \
+		done; \
 	done
 
 uninstall-hook:
-	cd $(DESTDIR)$(bindir) && \
+	cd "$(DESTDIR)$(bindir)" && \
 	for pair in $(links); do \
 		link=`echo $$pair | sed 's/^.*-//' | sed '$(transform)'` && \
-		rm -f $$link; \
+		rm -f "$$link"; \
 	done
-	cd $(DESTDIR)$(mandir)/man1 && \
-	for pair in $(links); do \
-		link=`echo $$pair | sed 's/^.*-//' | sed '$(transform)'` && \
-		rm -f $$link.1; \
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
+	for lang in . $$languages; do \
+		for pair in $(links); do \
+			target=`echo $$pair | sed 's/-.*$$//' \
+					| sed '$(transform)'` && \
+			link=`echo $$pair | sed 's/^.*-//' \
+					| sed '$(transform)'` && \
+			rm -f "$(DESTDIR)$(mandir)/$$lang/man1/$$target.1" \
+				"$(DESTDIR)$(mandir)/$$lang/man1/$$link.1"; \
+		done; \
 	done
diff --git a/src/xz/Makefile.am b/src/xz/Makefile.am
index 0890aad7..4bc64f36 100644
--- a/src/xz/Makefile.am
+++ b/src/xz/Makefile.am
@@ -81,31 +81,53 @@ xzlinks += lzma unlzma lzcat
 endif
 
 install-exec-hook:
-	cd $(DESTDIR)$(bindir) && \
+	cd "$(DESTDIR)$(bindir)" && \
 	target=`echo xz | sed '$(transform)'`$(EXEEXT) && \
 	for name in $(xzlinks); do \
 		link=`echo $$name | sed '$(transform)'`$(LN_EXEEXT) && \
-		rm -f $$link && \
-		$(LN_S) $$target $$link; \
+		rm -f "$$link" && \
+		$(LN_S) "$$target" "$$link"; \
 	done
 
+# The installation of translated man pages abuses Automake internals
+# by calling "install-man" with redefined dist_man_MANS and man_MANS.
+# If this breaks some day, don't blame Automake developers.
 install-data-hook:
-	cd $(DESTDIR)$(mandir)/man1 && \
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
 	target=`echo xz | sed '$(transform)'` && \
-	for name in $(xzlinks); do \
-		link=`echo $$name | sed '$(transform)'` && \
-		rm -f $$link.1 && \
-		$(LN_S) $$target.1 $$link.1; \
+	for lang in . $$languages; do \
+		man="$(top_srcdir)/po4a/man/$$lang/xz.1" ; \
+		if test -f "$$man"; then \
+			$(MAKE) dist_man_MANS="$$man" man_MANS= \
+				mandir="$(mandir)/$$lang" install-man; \
+		fi; \
+		man1dir="$(DESTDIR)$(mandir)/$$lang/man1" && \
+		if test -f "$$man1dir/$$target.1"; then ( \
+			cd "$$man1dir" && \
+			for name in $(xzlinks); do \
+				link=`echo $$name | sed '$(transform)'` && \
+				rm -f "$$link.1" && \
+				$(LN_S) "$$target.1" "$$link.1"; \
+			done \
+		); fi; \
 	done
 
 uninstall-hook:
-	cd $(DESTDIR)$(bindir) && \
+	cd "$(DESTDIR)$(bindir)" && \
 	for name in $(xzlinks); do \
 		link=`echo $$name | sed '$(transform)'`$(LN_EXEEXT) && \
-		rm -f $$link; \
+		rm -f "$$link"; \
 	done
-	cd $(DESTDIR)$(mandir)/man1 && \
-	for name in $(xzlinks); do \
-		link=`echo $$name | sed '$(transform)'` && \
-		rm -f $$link.1; \
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
+	for lang in . $$languages; do \
+		for name in xz $(xzlinks); do \
+			name=`echo $$name | sed '$(transform)'` && \
+			rm -f "$(DESTDIR)$(mandir)/$$lang/man1/$$name.1"; \
+		done; \
 	done
diff --git a/src/xzdec/Makefile.am b/src/xzdec/Makefile.am
index 5ff8e373..90f1e922 100644
--- a/src/xzdec/Makefile.am
+++ b/src/xzdec/Makefile.am
@@ -50,6 +50,7 @@ lzmadec_LDADD = $(xzdec_LDADD)
 
 
 bin_PROGRAMS =
+lzmadecmanlink =
 
 if COND_XZDEC
 bin_PROGRAMS += xzdec
@@ -60,23 +61,51 @@ if COND_LZMADEC
 bin_PROGRAMS += lzmadec
 
 # Create the symlink lzmadec.1->xzdec.1 only if xzdec.1 was installed.
-# This is better than creating a dangling symlink, especially
-# because creating the link may fail due to the directory being missing.
-#
-# FIXME: The correct solution would be to install xzdec.1 as lzmadec.1
-# but I don't know what is the sane way to do it and since this is a bit
-# unusual situation anyway, it's not that important.
+# This is better than creating a dangling symlink. The correct solution
+# would be to install xzdec.1 as lzmadec.1 but this code is already too
+# complicated so I won't do it. Installing only lzmadec is a bit unusual
+# situation anyway so it's not that important.
 if COND_XZDEC
+lzmadecmanlink += lzmadec
+endif
+endif
+
+if COND_XZDEC
+# The installation of translated man pages abuses Automake internals
+# by calling "install-man" with redefined dist_man_MANS and man_MANS.
+# If this breaks some day, don't blame Automake developers.
 install-data-hook:
-	cd $(DESTDIR)$(mandir)/man1 && \
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
 	target=`echo xzdec | sed '$(transform)'` && \
 	link=`echo lzmadec | sed '$(transform)'` && \
-	rm -f $$link.1 && \
-	$(LN_S) $$target.1 $$link.1
+	for lang in . $$languages; do \
+		man="$(top_srcdir)/po4a/man/$$lang/xzdec.1" ; \
+		if test -f "$$man"; then \
+			$(MAKE) dist_man_MANS="$$man" man_MANS= \
+				mandir="$(mandir)/$$lang" install-man; \
+		fi; \
+		man1dir="$(DESTDIR)$(mandir)/$$lang/man1" && \
+		if test -f "$$man1dir/$$target.1"; then \
+			if test -n "$(lzmadecmanlink)"; then ( \
+				cd "$$man1dir" && \
+				rm -f "$$link.1" && \
+				$(LN_S) "$$target.1" "$$link.1" \
+			); fi; \
+		fi; \
+	done
 
 uninstall-hook:
-	cd $(DESTDIR)$(mandir)/man1 && \
-	link=`echo lzmadec | sed '$(transform)'` && \
-	rm -f $$link.1
-endif
+	languages= ; \
+	if test "$(USE_NLS)" = yes && test -d "$(top_srcdir)/po4a/man"; then \
+		languages=`ls "$(top_srcdir)/po4a/man"`; \
+	fi; \
+	for lang in . $$languages; do \
+		for name in xzdec $(lzmadecmanlink); do \
+			name=`echo $$name | sed '$(transform)'` && \
+			rm -f "$(DESTDIR)$(mandir)/$$lang/man1/$$name.1"; \
+		done; \
+	done
 endif