3 # Copyright © 2011-2014 Nick Bowler
5 # Prepare the Gnulib tree for inclusion into a non-recursive automake build.
6 # While the output of gnulib-tool is "include"-able if the --makefile-name
7 # option is used, it is still not suitable for non-recursive use for a couple
8 # reasons; chief among them is that filenames are not relative to the top
11 # This script postprocesses the gnulib-tool output to produce something that
12 # is intended to be suitable for inclusion into such non-recursive build
13 # environments. Since the integration involves both configure.ac and
14 # Makefile.am, the output must be included into _both_. Supposing the output
15 # is written to lib/gnulib.mk, you would add:
17 # m4_include([lib/gnulib.mk]) # to configure.ac, after any call to gl_INIT
18 # include $(top_srcdir)/lib/gnulib.mk # to Makefile.am
20 # You must also arrange for the Gnulib-generated header files to be built
21 # before the object files which depend on them; the most robust way to do this
22 # is by explicit prerequisites, for example:
25 # $(foo_OBJECTS): $(gnulib_headers)
27 # The $(gnulib_headers) variable will expand to GNU-make order-only
28 # prerequisites when available, avoiding spurious incremental rebuilds when
29 # unused headers are changed. If this feature is not available, it will
30 # expand to ordinary prerequisites. It is therefore only appropriate for use
31 # in target prerequisites; the $(gnulib_raw_headers) variable may be used in
32 # other contexts when only the list of header files is required.
34 # This script also provides machinery for Gnulib symbol renaming via the
35 # glconfig.mk Makefile.am snippet; use of this feature is optional.
37 # Most of the specific transformations are documented below.
39 # License WTFPL2: Do What The Fuck You Want To Public License, version 2.
40 # This is free software: you are free to do what the fuck you want to.
41 # There is NO WARRANTY, to the extent permitted by law.
51 Getopt::Long::Configure("gnu_getopt", "no_auto_abbrev");
53 "o|output=s" => \$output,
54 "i|input=s" => \$input,
57 open STDOUT, ">", $output or die "$output: $!\n" if (defined $output);
58 open STDIN, "<", $input or die "$input: $!\n" if (defined $input);
60 my $printed_header = 0;
63 # Hashes to record make variables used in the automake source. The allvars
64 # hash contains variables actually assigned in the Makefile, sourcevars
65 # contains variables used as filenames. Keys are the variable name, and
66 # the value is always set to 1.
67 my (%allvars, %sourcevars);
76 $file =~ m|(?:.+/)?([^/]+)/?|;
83 if ($word =~ /^\$\(([[:word:].]+)\)$/) {
84 # Don't touch variables now, but record them for later.
86 } elsif ($word =~ /^\$\((?:top_)?(?:srcdir|builddir)\)/) {
87 # Do nothing. Generic transformation will take care of
88 # $(srcdir) and $(builddir).
89 } elsif ($word =~ /^[[:word:].+\/-]+$/) {
90 # Mangle the filename. Assume that all relevant files start
91 # with a non-dot (so we don't transform suffix rules) and
92 # contain at least one dot (so we don't transform phony rules).
93 $word = "lib/$word" if ($word =~ /^[^.]+\./);
95 print STDERR "$0:$line: warning: unrecognized source file: $word\n";
101 sub mangle_variable {
104 $raw =~ /([^=]+=)[[:space:]]*(.*)/s;
105 my ($left, @right) = ($1, split(/[[:space:]]+/, $2));
107 return join(" ", ($left, map(mangle_file($_), @right))) . "\n";
113 $raw =~ /([^:]+):[[:space:]]*(.*)/s;
114 my @left = split(/[[:space:]]+/, $1);
115 my @right = split(/[[:space:]]+/, $2);
117 @left = map(mangle_file($_), @left);
118 @right = map(mangle_file($_), @right);
120 return join(" ", @left) . ": " . join(" ", @right) . "\n";
126 # Combine line splices.
134 if (!$printed_header) {
135 print "# Postprocessed by ", basename($0), "\n\n";
137 # BEGIN AUTOMAKE/M4 POLYGLOT \
138 m4_unquote(m4_argn([2], [
139 .PHONY: # Automake code follows
141 # This trick should define gnulib_orderonly to | iff we're using GNU make.
142 gnulib_make_features = $(.FEATURES)
143 gnulib_have_orderonly = $(findstring order-only,$(gnulib_make_features))
144 gnulib_orderonly = $(gnulib_have_orderonly:order-only=|)
145 gnulib_core_headers =
146 gnulib_raw_headers = $(gnulib_core_headers)
147 gnulib_headers = $(gnulib_orderonly) $(gnulib_raw_headers)
149 # Oddly, gnulib tries to add to MOSTLYCLEANDIRS (which is *not* an automake
150 # variable) without defining it.
158 # For some reason, gnulib-tool adds core dumps to "make mostlyclean".
159 # Since these files are (hopefully!) not created by make, they should
161 drop if (/^MOSTLYCLEANFILES.*core/);
163 # Some modules set AM_CPPFLAGS/AM_CFLAGS/etc. in a manner that is not
164 # useful for non-recursive builds. Strip them out.
165 drop if (/^(AM_CPPFLAGS|AM_CFLAGS)/);
167 # Library dependencies are added automatically to libgnu.la by
168 # gnulib-tool. Unfortunately, this means that everything linking
169 # against libgnu.la is forced to pull in the same deps, even if they're
170 # unneeded. Furthermore, a libtool linker flag reordering bug prevents
171 # --as-needed from stripping out the useless deps, so it's better to
172 # handle them all manually.
175 # Current uses of SUFFIXES in gnulib are pointless since Automake will
176 # figure it out all on its own. Strip it out.
177 drop if (/SUFFIXES/);
179 # Rewrite automake hook targets to be more generic.
180 if (s/^(.*)-local:/\1-gnulib:/) {
181 print ".PHONY: $1-gnulib\n";
182 print "$1-local: $1-gnulib\n";
186 # We need to mangle filenames in make variables; prepending a lib/ on
187 # relative paths. The following should catch all variable assignments
188 # that need mangling.
189 if (/^([[:word:]]+)[[:space:]]*\+?=/) {
192 if (/_SOURCES|CLEANFILES|EXTRA_DIST|[[:upper:]]+_H/) {
193 $_ = mangle_variable($_);
197 # BUILT_SOURCES has similar problems to recursive make: inadequate
198 # dependencies lead to incorrect builds. Collect them into an
199 # ordinary variable so we can deal with them later.
200 s/BUILT_SOURCES/gnulib_core_headers/;
202 # Targets are similar to variables: the target and its dependencies
203 # need to be mangled.
205 $_ = mangle_target($_);
208 # MKDIR_P commands need to be fixed up; in principle Gnulib could also
209 # be patched here to use $(@D) instead (and thus automatically benefit
210 # from the target being fixed up), but this will do for now.
211 s/^(\t.*\$\(MKDIR_P\)) ([[:alnum:]]+)$/\1 lib\/\2/;
213 # When using conditional-dependencies, *CLEANFILES can end up
214 # depending on the configuration. This means that "make distclean"
215 # may not actually delete everything if the configuration changes
216 # after building the package. Stash all the variables for later so
217 # they can be moved outside of any conditional.
218 if (/(CLEANFILES|CLEANDIRS)[[:space:]]*\+=/) {
219 push(@cleanfiles, $_);
223 # Change t-$@ to $@-t as the former will break if $@ has a directory
227 # Finally, references to $(srcdir) and $(builddir) need to be fixed up.
228 s:\$\(srcdir\):\$\(top_srcdir\)/lib:g;
229 s:\$\(builddir\):\$\(top_builddir\)/lib:g;
230 } continue { s/(\n.)/\\\1/g; print; };
233 gnulib_lt_objects = $(libgnu_la_OBJECTS) $(gl_LTLIBOBJS)
234 $(gnulib_lt_objects): $(gnulib_headers)
240 ], [dnl M4 code follows
242 AC_SUBST([GLSRC], [lib])
243 AC_CONFIG_LIBOBJ_DIR([lib])
245 AC_DEFUN_ONCE([DX_GLSYM_PREFIX], [dnl
246 AC_REQUIRE([DX_EXPORTED_SH])
247 AC_SUBST([GLSYM_PREFIX], [$1])
249 AC_CONFIG_COMMANDS_PRE([DX_GLSYM_PREFIX([${PACKAGE}__])])
251 m4_foreach([gl_objvar], [[gl_LIBOBJS], [gl_LTLIBOBJS]], [dnl
252 set x $gl_objvar; shift
254 while test ${#} -gt 0; do
255 gl_objvar="$gl_objvar lib/${1}"; shift
260 # Some filenames are AC_SUBSTed by the Gnulib macros, and thus we need to
261 # prepend lib/ if and only if they're not empty. Unfortunately, make is not
262 # powerful to do this, so we need to put this transformation into configure
263 # itself by defining a new autoconf macro.
265 foreach (keys %sourcevars) {
266 print "$_=\${$_:+lib/\$$_}\n" unless $allvars{$_};
273 # END AUTOMAKE/M4 POLYGLOT