#!/usr/bin/env perl
#
-# Copyright © 2011 Nick Bowler
+# Copyright © 2011-2014, 2020-2023 Nick Bowler
#
# Prepare the Gnulib tree for inclusion into a non-recursive automake build.
+# While the output of gnulib-tool is "include"-able if the --makefile-name
+# option is used, it is still not suitable for non-recursive use for a couple
+# reasons; chief among them is that filenames are not relative to the top
+# source directory.
+#
+# This script postprocesses the gnulib-tool output to produce something
+# that is intended to be suitable for inclusion into such non-recursive
+# build environments. Since the integration involves both configure.ac
+# and Makefile.am, the output must be included into _both_. Supposing
+# the output is written to lib/gnulib.mk, you would add:
+#
+# m4_include([lib/gnulib.mk]) # to configure.ac, after any call to gl_INIT
+# include $(top_srcdir)/lib/gnulib.mk # to Makefile.am
+#
+# You must also arrange for the Gnulib-generated header files to be built
+# before the object files which depend on them; the most robust way to do
+# this is by explicit prerequisites, for example:
+#
+# bin_PROGRAMS = foo
+# $(foo_OBJECTS): $(gnulib_headers)
+#
+# The $(gnulib_headers) variable will expand to GNU-make order-only
+# prerequisites when available, avoiding spurious incremental rebuilds when
+# unused headers are changed. If this feature is not available, it will
+# expand to ordinary prerequisites. It is therefore only appropriate for
+# use in target prerequisites; the $(gnulib_raw_headers) variable may be
+# used in other contexts when only the list of header files is required.
+#
+# This script also provides machinery for Gnulib symbol renaming via the
+# glconfig.mk Makefile.am snippet; use of this feature is optional.
+#
+# Most of the specific transformations are documented below.
#
# License WTFPL2: Do What The Fuck You Want To Public License, version 2.
# This is free software: you are free to do what the fuck you want to.
# There is NO WARRANTY, to the extent permitted by law.
use strict;
-use List::Compare;
use Getopt::Long;
my $output = undef;
my $input = undef;
-my $m4output = undef;
-my $m4macro = "DX_FIX_GNULIB";
+
+my $use_libtool = undef;
+my $for_library = undef;
+
+my $line = 0;
Getopt::Long::Configure("gnu_getopt", "no_auto_abbrev");
GetOptions(
"o|output=s" => \$output,
"i|input=s" => \$input,
- "m|m4output=s" => \$m4output,
- "M|m4macro=s" => \$m4macro,
+ "library" => sub { $for_library = 1; },
+ "program" => sub { $for_library = 0; },
);
open STDOUT, ">", $output or die "$output: $!\n" if (defined $output);
open STDIN, "<", $input or die "$input: $!\n" if (defined $input);
my $printed_header = 0;
-my (%allvars, %sourcevars);
my @cleanfiles;
+# Hashes to record make variables used in the automake source. The allvars
+# hash contains variables actually assigned in the Makefile, sourcevars
+# contains variables used as filenames. Keys are the variable name, and
+# the value is always set to 1.
+my (%allvars, %sourcevars);
+
+# Collected names of subdirectories that may need to be created at build time.
+# The keys are directory names, the values are targets.
+my %gl_dirstamps;
+
+# State to drop MKDIR_P lines that have been replaced by dirstamps.
+my ($have_dirstamp) = (0);
+
sub drop {
undef $_;
next;
# Do nothing. Generic transformation will take care of
# $(srcdir) and $(builddir).
} elsif ($word =~ /^[[:word:].+\/-]+$/) {
- # Fix up things that look like filenames.
- $word = "lib/$word";
+ # Mangle the filename. Assume that all relevant files start
+ # with a non-dot (so we don't transform suffix rules) and
+ # contain at least one dot (so we don't transform phony rules).
+ $word = "lib/$word" if ($word =~ /^[^.]+\./);
} else {
- print STDERR "$0: warning: unrecognized source file: $word\n";
+ print STDERR "$0:$line: warning: unrecognized source file: $word\n";
}
return "$word";
sub mangle_variable {
my $raw = shift;
- $raw =~ /([^=]+=)[[:space:]]*(.*)/;
+ $raw =~ /([^=]+=)[[:space:]]*(.*)/s;
my ($left, @right) = ($1, split(/[[:space:]]+/, $2));
return join(" ", ($left, map(mangle_file($_), @right))) . "\n";
sub mangle_target {
my $raw = shift;
- $raw =~ /([^:]+):[[:space:]]*(.*)/;
+ $raw =~ /([^:]+):[[:space:]]*(.*)/s;
my @left = split(/[[:space:]]+/, $1);
my @right = split(/[[:space:]]+/, $2);
@left = map(mangle_file($_), @left);
@right = map(mangle_file($_), @right);
- return join(" ", @left) . ": " . join(" ", @right) . "\n";
+ my @dirstamps = get_dirstamps(@left);
+
+ return join(" ", @left) . ": " . join(" ", @dirstamps, @right) . "\n";
+}
+
+sub get_dirstamps {
+ my %h;
+
+ foreach (@_) {
+ next unless $_[0] =~ m|^(lib(/.*)?)/[^/]*$|;
+
+ $h{$gl_dirstamps{$1} = "$1/\$(am__dirstamp)"} = 1;
+ }
+
+ return keys %h;
}
while (<STDIN>) {
+ $line++;
+
+ # Combine line splices.
+ while (s/\\$//) {
+ $line++;
+ $_ = $_ . <STDIN>
+ }
+
next if (/^#/);
if (!$printed_header) {
print "# Postprocessed by ", basename($0), "\n\n";
print <<'EOF';
+# BEGIN AUTOMAKE/M4 POLYGLOT \
+m4_unquote(m4_argn([2], [
+.PHONY: # Automake code follows
+
# This trick should define gnulib_orderonly to | iff we're using GNU make.
-gnulib_have_orderonly = $(findstring order-only,$(.FEATURES))
+gnulib_make_features = $(.FEATURES)
+gnulib_have_orderonly = $(findstring order-only,${gnulib_make_features})
gnulib_orderonly = $(gnulib_have_orderonly:order-only=|)
-gnulib_core_headers = $(gnulib_orderonly)
-gnulib_src_headers = $(gnulib_core_headers)
-gnulib_headers = $(gnulib_src_headers)
+gnulib_core_headers =
+gnulib_raw_headers = $(gnulib_core_headers)
+gnulib_headers = $(gnulib_orderonly) $(gnulib_raw_headers)
+
+# Oddly, gnulib tries to add to MOSTLYCLEANDIRS (which is *not* an automake
+# variable) without defining it.
+MOSTLYCLEANDIRS =
EOF
$printed_header = 1;
drop;
}
+ # Locate the libgnu definition to determine whether or not the user is
+ # using libtool mode in gnulib-tool. Default to program mode if they
+ # are not, which will avoid pulling in the glsym dependencies.
+ #
+ # Convert noinst to EXTRA, that way libgnu will not be built unless
+ # something actually depends on it (which is typically the case).
+ if (/^noinst_LIBRARIES.*libgnu.a/) {
+ s/^noinst/EXTRA/;
+ $for_library = 0 unless defined $for_library;
+ $use_libtool = 0;
+ }
+ if (/^noinst_LTLIBRARIES.*libgnu.la/) {
+ s/^noinst/EXTRA/;
+ $for_library = 1 unless defined $for_library;
+ $use_libtool = 1;
+ }
+
# For some reason, gnulib-tool adds core dumps to "make mostlyclean".
# Since these files are (hopefully!) not created by make, they should
# not be cleaned.
# useful for non-recursive builds. Strip them out.
drop if (/^(AM_CPPFLAGS|AM_CFLAGS)/);
+ # We don't care about upstream warning flags that just result in adding
+ # massive amounts of additional build rules for no reason.
+ if (/_CFLAGS/) {
+ s/ *\$\(GL_CFLAG_GNULIB_WARNINGS\)// if /_CFLAGS\s*=/;
+ }
+
+ # Drop superfluous CFLAGS assignments (which may be created by above
+ # transformation).
+ drop if /_CFLAGS\s*=\s*\$\(AM_CFLAGS\)\s*$/;
+
+ # Library dependencies are added automatically to libgnu.la by
+ # gnulib-tool. Unfortunately, this means that everything linking
+ # against libgnu.la is forced to pull in the same deps, even if they're
+ # unneeded. Furthermore, a libtool linker flag reordering bug prevents
+ # --as-needed from stripping out the useless deps, so it's better to
+ # handle them all manually.
+ drop if (/LDFLAGS/);
+
+ # Current uses of SUFFIXES in gnulib are pointless since Automake will
+ # figure it out all on its own. Strip it out.
+ drop if (/SUFFIXES/);
+
# Rewrite automake hook targets to be more generic.
if (s/^(.*)-local:/\1-gnulib:/) {
print ".PHONY: $1-gnulib\n";
print "$1-local: $1-gnulib\n";
s/$1-generic//;
-
- # Don't let these targets get confused with filenames below.
- next;
}
# We need to mangle filenames in make variables; prepending a lib/ on
if (/^([[:word:]]+)[[:space:]]*\+?=/) {
$allvars{$1} = 1;
- if (/_SOURCES|CLEANFILES|EXTRA_DIST|[[:upper:]]+_H/) {
+ if ($1 =~ /(_SOURCES|CLEANFILES|EXTRA_DIST|[[:upper:]]+_H)$/) {
$_ = mangle_variable($_);
}
}
# Targets are similar to variables: the target and its dependencies
# need to be mangled.
- if (/:/) {
+ if (/^([^\t:]*):/) {
$_ = mangle_target($_);
+ $have_dirstamp = /am__dirstamp/;
}
+ # MKDIR_P commands need to be fixed up; in principle Gnulib could also
+ # be patched here to use $(@D) instead (and thus automatically benefit
+ # from the target being fixed up), but this will do for now.
+ s/^(\t.*\$\(MKDIR_P\)) ([[:alnum:]]+)$/\1 lib\/\2/;
+
# When using conditional-dependencies, *CLEANFILES can end up
# depending on the configuration. This means that "make distclean"
# may not actually delete everything if the configuration changes
# after building the package. Stash all the variables for later so
# they can be moved outside of any conditional.
- if (/CLEANFILES/) {
+ if (/(CLEANFILES|CLEANDIRS)[[:space:]]*\+=/) {
push(@cleanfiles, $_);
drop;
}
- # Finally, references to $(srcdir) and $(builddir) need to be fixed up.
+ # Change t-$@ to $@-t as the former will break if $@ has a directory
+ # component.
+ s/t-\$@/\$\@-t/g;
+
+ # $(srcdir), $(builddir) and %reldir% need to be fixed up.
s:\$\(srcdir\):\$\(top_srcdir\)/lib:g;
s:\$\(builddir\):\$\(top_builddir\)/lib:g;
-} continue { print };
+ s:%reldir%:lib:g;
-print <<'EOF';
+ # If we installed a dirstamp prerequisite for this target, don't
+ # emit the mkdir line which creates the output directory.
+ if ($have_dirstamp && m|\$[({]MKDIR_P[})][ '"]*lib/|) {
+ drop unless s/^(\t\$[({](AM_V_GEN|gl_V_at)[})]).*/\1:/;
+ }
+ undef $have_dirstamp if /^\t/;
+} continue { s/(\n.)/\\\1/g; print; };
+
+# Define a bunch of fake programs which will ensure Automake produces the
+# necessary dirstamp rules, as unfortunately we cannot know in advance which
+# will be generated, and the usual Automake behaviour where generated rules
+# are suppressed by rules in Makefile.am doesn't actaully work for these.
+print <<EOF foreach (keys %gl_dirstamps);
+EXTRA_PROGRAMS += $_/gl-dirstamp
+${\(y|/|_|r)}_gl_dirstamp_SOURCES =
+EOF
+
+print <<'EOF' if ($use_libtool);
gnulib_lt_objects = $(libgnu_la_OBJECTS) $(gl_LTLIBOBJS)
-$(gnulib_lt_objects): $(gnulib_src_headers)
+gnulib_objects = $(gnulib_lt_objects)
+gnulib_all_symfiles = $(gnulib_lt_objects:.lo=.glsym)
+$(gnulib_objects): $(gnulib_headers)
EOF
+print <<'EOF' if (!$use_libtool);
+gnulib_objects = $(libgnu_a_OBJECTS) $(gl_LIBOBJS)
+gnulib_all_symfiles = $(gnulib_objects:.@OBJEXT@=.glsym)
+$(gnulib_objects): $(gnulib_headers)
+EOF
+
print @cleanfiles;
-# Some filenames are AC_SUBSTed by the Gnulib macros, and thus we need to
-# prepend lib/ if and only if they're not empty. Unfortunately, make is not
-# powerful to do this, so we need to put this transformation into configure
-# itself by defining a new autoconf macro.
-if (defined $m4output) {
- my $lc = List::Compare->new('-u', '-a', \%sourcevars, \%allvars);
- my @vars = $lc->get_unique;
-
- open(M4OUT, '>', $m4output) or die "$m4output: $!\n";
-
- print M4OUT <<EOF;
-dnl This file was generated by fix-gnulib.pl
-dnl
-dnl Usage: DX_FIX_GNULIB([symbol-prefix])
-dnl where symbol-prefix is the application-specific symbol prefix to apply
-dnl to Gnulib's symbols. Defaults to \${PACKAGE}__.
-dnl top-level source directory; e.g. lib.
-AC_DEFUN([$m4macro], [dnl
+print <<'EOF';
+if FALSE
+], [dnl M4 code follows
+
+AC_SUBST([GLSRC], [lib])
+AC_CONFIG_LIBOBJ_DIR([lib])
+
+AC_DEFUN_ONCE([DX_GLSYM_PREFIX],
+[AC_REQUIRE([DX_AUTOMAKE_COMPAT])AC_REQUIRE([DX_EXPORTED_SH])dnl
+AC_SUBST([GLSYM_PREFIX], [$1])dnl
+AC_SUBST([gnulib_symfiles], ['$(gnulib_all_symfiles)'])])
+EOF
+
+print <<'EOF' if ($for_library);
+AC_CONFIG_COMMANDS_PRE([DX_GLSYM_PREFIX([${PACKAGE}__])])
EOF
- print M4OUT <<'EOF';
-GLSRC=lib
-GLSYM_PREFIX='ifelse([$1], [], [${PACKAGE}__], [$1])'
-AC_SUBST([GLSRC])
-AC_SUBST([GLSYM_PREFIX])
+print <<'EOF';
m4_foreach([gl_objvar], [[gl_LIBOBJS], [gl_LTLIBOBJS]], [dnl
set x $gl_objvar; shift
gl_objvar=
done
])
EOF
- foreach (@vars) {
- print M4OUT "$_=\${$_:+lib/\$$_}\n";
- }
- print M4OUT "])\n";
- close M4OUT;
+# Some filenames are AC_SUBSTed by the Gnulib macros, and thus we need to
+# prepend lib/ if and only if they're not empty. Unfortunately, make is not
+# powerful to do this, so we need to put this transformation into configure
+# itself by defining a new autoconf macro.
+
+foreach (keys %sourcevars) {
+ print "$_=\${$_:+lib/\$$_}\n" unless $allvars{$_};
}
+
+print <<'EOF';
+], [
+endif
+# ]))dnl
+# END AUTOMAKE/M4 POLYGLOT
+EOF