xref: /openbsd-src/gnu/usr.bin/perl/cpan/ExtUtils-MakeMaker/lib/ExtUtils/Mkbootstrap.pm (revision a0747c9f67a4ae71ccb71e62a28d1ea19e06a63c)
1package ExtUtils::Mkbootstrap;
2
3# There's just too much Dynaloader incest here to turn on strict vars.
4use strict 'refs';
5
6our $VERSION = '7.44';
7$VERSION =~ tr/_//d;
8
9require Exporter;
10our @ISA = ('Exporter');
11our @EXPORT = ('&Mkbootstrap');
12
13use Config;
14
15our $Verbose = 0;
16
17
18sub Mkbootstrap {
19    my($baseext, @bsloadlibs)=@_;
20    @bsloadlibs = grep($_, @bsloadlibs); # strip empty libs
21
22    print "	bsloadlibs=@bsloadlibs\n" if $Verbose;
23
24    # We need DynaLoader here because we and/or the *_BS file may
25    # call dl_findfile(). We don't say `use' here because when
26    # first building perl extensions the DynaLoader will not have
27    # been built when MakeMaker gets first used.
28    require DynaLoader;
29
30    rename "$baseext.bs", "$baseext.bso"
31      if -s "$baseext.bs";
32
33    if (-f "${baseext}_BS"){
34	$_ = "${baseext}_BS";
35	package DynaLoader; # execute code as if in DynaLoader
36	local($osname, $dlsrc) = (); # avoid warnings
37	($osname, $dlsrc) = @Config::Config{qw(osname dlsrc)};
38	$bscode = "";
39	unshift @INC, ".";
40	require $_;
41	shift @INC;
42    }
43
44    if ($Config{'dlsrc'} =~ /^dl_dld/){
45	package DynaLoader;
46	push(@dl_resolve_using, dl_findfile('-lc'));
47    }
48
49    my(@all) = (@bsloadlibs, @DynaLoader::dl_resolve_using);
50    my($method) = '';
51    if (@all || (defined $DynaLoader::bscode && length $DynaLoader::bscode)){
52	open my $bs, ">", "$baseext.bs"
53		or die "Unable to open $baseext.bs: $!";
54	print "Writing $baseext.bs\n";
55	print "	containing: @all" if $Verbose;
56	print $bs "# $baseext DynaLoader bootstrap file for $^O architecture.\n";
57	print $bs "# Do not edit this file, changes will be lost.\n";
58	print $bs "# This file was automatically generated by the\n";
59	print $bs "# Mkbootstrap routine in ExtUtils::Mkbootstrap (v$VERSION).\n";
60	if (@all) {
61	    print $bs "\@DynaLoader::dl_resolve_using = ";
62	    # If @all contains names in the form -lxxx or -Lxxx then it's asking for
63	    # runtime library location so we automatically add a call to dl_findfile()
64	    if (" @all" =~ m/ -[lLR]/){
65		print $bs "  dl_findfile(qw(\n  @all\n  ));\n";
66	    } else {
67		print $bs "  qw(@all);\n";
68	    }
69	}
70	# write extra code if *_BS says so
71	print $bs $DynaLoader::bscode if $DynaLoader::bscode;
72	print $bs "\n1;\n";
73	close $bs;
74    }
75}
76
771;
78
79__END__
80
81=head1 NAME
82
83ExtUtils::Mkbootstrap - make a bootstrap file for use by DynaLoader
84
85=head1 SYNOPSIS
86
87  Mkbootstrap
88
89=head1 DESCRIPTION
90
91Mkbootstrap typically gets called from an extension Makefile.
92
93There is no C<*.bs> file supplied with the extension. Instead, there may
94be a C<*_BS> file which has code for the special cases, like posix for
95berkeley db on the NeXT.
96
97This file will get parsed, and produce a maybe empty
98C<@DynaLoader::dl_resolve_using> array for the current architecture.
99That will be extended by $BSLOADLIBS, which was computed by
100ExtUtils::Liblist::ext(). If this array still is empty, we do nothing,
101else we write a .bs file with an C<@DynaLoader::dl_resolve_using>
102array.
103
104The C<*_BS> file can put some code into the generated C<*.bs> file by
105placing it in C<$bscode>. This is a handy 'escape' mechanism that may
106prove useful in complex situations.
107
108If @DynaLoader::dl_resolve_using contains C<-L*> or C<-l*> entries then
109Mkbootstrap will automatically add a dl_findfile() call to the
110generated C<*.bs> file.
111
112=cut
113