From 1896ef8419a2d9e222e0467e42b3792a9983fc14 Mon Sep 17 00:00:00 2001
From: Tom Tromey <tromey@redhat.com>
Date: Wed, 10 Jul 2002 05:36:46 +0000
Subject: [PATCH] 	For PR automake/286: 	* automake.texi (Tags):
 Document ctags. 	* automake.in (handle_tags): Handle ctags. 	*
 lib/am/tags.am (CTAGS): New macro. 	(CTAGSFLAGS): Likewise. 
 (ctags): New target. 	(distclean-tags): Remove `tags'.

---
 ChangeLog      |  8 ++++++++
 automake.in    | 16 +++++++++++++++-
 automake.texi  |  6 ++++++
 lib/am/tags.am | 35 +++++++++++++++++++++++++++++++++--
 4 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index fa0b212..81663d3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2002-07-09  Tom Tromey  <tromey@redhat.com>
 
+	For PR automake/286:
+	* automake.texi (Tags): Document ctags.
+	* automake.in (handle_tags): Handle ctags.
+	* lib/am/tags.am (CTAGS): New macro.
+	(CTAGSFLAGS): Likewise.
+	(ctags): New target.
+	(distclean-tags): Remove `tags'.
+
 	* lib/am/depend2.am: Reworked syntax to avoid parsing problem.
 
 	* lib/am/depend2.am: Search in srcdir and builddir for %SOURCE%
diff --git a/automake.in b/automake.in
index 7a1af9b..753e9a1 100755
--- a/automake.in
+++ b/automake.in
@@ -3720,6 +3720,7 @@ sub handle_data
 sub handle_tags
 {
     my @tag_deps = ();
+    my @ctag_deps = ();
     if (variable_defined ('SUBDIRS'))
     {
 	$output_rules .= ("tags-recursive:\n"
@@ -3731,6 +3732,16 @@ sub handle_tags
 			  . "\tdone\n");
 	push (@tag_deps, 'tags-recursive');
 	&depend ('.PHONY', 'tags-recursive');
+
+	$output_rules .= ("ctags-recursive:\n"
+			  . "\tlist=\'\$(SUBDIRS)\'; for subdir in \$\$list; do \\\n"
+			  # Never fail here if a subdir fails; it
+			  # isn't important.
+			  . "\t  test \"\$\$subdir\" = . || (cd \$\$subdir"
+			  . " && \$(MAKE) \$(AM_MAKEFLAGS) ctags); \\\n"
+			  . "\tdone\n");
+	push (@ctag_deps, 'ctags-recursive');
+	&depend ('.PHONY', 'ctags-recursive');
     }
 
     if (&saw_sources_p (1)
@@ -3751,7 +3762,8 @@ sub handle_tags
 	}
 	$output_rules .= &file_contents ('tags',
 					 ('CONFIG' => "@config",
-					  'DIRS'   => "@tag_deps"));
+					  'TAGSDIRS'   => "@tag_deps",
+					  'CTAGSDIRS'  => "@ctag_deps"));
 	&examine_variable ('TAGS_DEPENDENCIES');
     }
     elsif (reject_var ('TAGS_DEPENDENCIES',
@@ -3765,6 +3777,8 @@ sub handle_tags
 	# Otherwise, it would be possible for a top-level "make TAGS"
 	# to fail because some subdirectory failed.
 	$output_rules .= "tags: TAGS\nTAGS:\n\n";
+	# Ditto ctags.
+	$output_rules .= "ctags: CTAGS\nCTAGS:\n\n";
     }
 }
 
diff --git a/automake.texi b/automake.texi
index 06c355a..9990aad 100644
--- a/automake.texi
+++ b/automake.texi
@@ -4323,6 +4323,12 @@ want to set @samp{TAGS_DEPENDENCIES}.  The contents of this variable
 are added directly to the dependencies for the @code{tags} target.
 @vindex TAGS_DEPENDENCIES
 
+Automake also generates a @code{ctags} target which can be used to
+build @command{vi}-style @file{tags} files.  The variable @code{CTAGS}
+is the name of the program to invoke (by default @samp{ctags});
+@code{CTAGSFLAGS} can be used by the user to pass additional flags,
+and @code{AM_CTAGSFLAGS} can be used by the @file{Makefile.am}.
+
 Automake will also generate an @code{ID} target which will run
 @code{mkid} on the source.  This is only supported on a
 directory-by-directory basis.
diff --git a/lib/am/tags.am b/lib/am/tags.am
index f961a18..b34641d 100644
--- a/lib/am/tags.am
+++ b/lib/am/tags.am
@@ -44,7 +44,7 @@ ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
 ETAGS = etags
 ETAGSFLAGS =
 
-TAGS: %DIRS% $(HEADERS) $(SOURCES) %CONFIG% $(TAGS_DEPENDENCIES) \
+TAGS: %TAGSDIRS% $(HEADERS) $(SOURCES) %CONFIG% $(TAGS_DEPENDENCIES) \
 		$(TAGS_FILES) $(LISP)
 	tags=; \
 	here=`pwd`; \
@@ -70,6 +70,37 @@ TAGS: %DIRS% $(HEADERS) $(SOURCES) %CONFIG% $(TAGS_DEPENDENCIES) \
 	     $$tags $$unique
 
 
+## ------------- ##
+## vi-style tags ##
+## ------------- ##
+
+CTAGS = ctags
+CTAGSFLAGS =
+
+.PHONY: CTAGS ctags
+ctags: CTAGS
+
+## We have a dummy name here because `tags' has already been in use
+## for a long time to mean Emacs-style tags.  Oops.  This means the
+## dependencies here are useless.
+CTAGS: %CTAGSDIRS% $(HEADERS) $(SOURCES) %CONFIG% $(TAGS_DEPENDENCIES) \
+		$(TAGS_FILES) $(LISP)
+	tags=; \
+	here=`pwd`; \
+## Make sure the list of sources is unique.
+	list='$(SOURCES) $(HEADERS) %CONFIG% $(LISP) $(TAGS_FILES)'; \
+	unique=`for i in $$list; do \
+## Handle VPATH correctly.
+	    if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
+	  done | \
+	  $(AWK) '    { files[$$0] = 1; } \
+	       END { for (i in files) print i; }'`; \
+## Make sure we have something to run ctags on.
+	test -z "$(CTAGS_ARGS)$$tags$$unique" \
+	  || $(CTAGS) $(CTAGSFLAGS) $(AM_CTAGSFLAGS) $(CTAGS_ARGS) \
+	     $$tags $$unique
+
+
 ## --------------- ##
 ## `Global' tags.  ##
 ## --------------- ##
@@ -88,4 +119,4 @@ GTAGS:
 .PHONY distclean-am: distclean-tags
 
 distclean-tags:
-	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH
+	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
-- 
2.7.4