1#
2# Copyright (C) 2005 Nikolas Zimmermann <wildfox@kde.org>
3# Copyright (C) 2011 Google Inc.
4#
5# This library is free software; you can redistribute it and/or
6# modify it under the terms of the GNU Library General Public
7# License as published by the Free Software Foundation; either
8# version 2 of the License, or (at your option) any later version.
9#
10# This library is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13# Library General Public License for more details.
14#
15# You should have received a copy of the GNU Library General Public License
16# along with this library; see the file COPYING.LIB.  If not, write to
17# the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18# Boston, MA 02110-1301, USA.
19#
20
21use strict;
22use warnings;
23
24use Config;
25use IPC::Open2;
26use IPC::Open3;
27
28BEGIN {
29   use Exporter   ();
30   our ($VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS);
31   $VERSION     = 1.00;
32   @ISA         = qw(Exporter);
33   @EXPORT      = qw(&applyPreprocessor);
34   %EXPORT_TAGS = ( );
35   @EXPORT_OK   = ();
36}
37
38# Returns an array of lines.
39sub applyPreprocessor
40{
41    my $fileName = shift;
42    my $defines = shift;
43    my $preprocessor = shift;
44
45    my @args = ();
46    if (!$preprocessor) {
47        require Config;
48        if ($ENV{CC}) {
49            $preprocessor = $ENV{CC};
50        } elsif (($Config::Config{'osname'}) =~ /solaris/i) {
51            $preprocessor = "/usr/sfw/bin/gcc";
52        } elsif (-x "/usr/bin/clang") {
53            $preprocessor = "/usr/bin/clang";
54        } else {
55            $preprocessor = "/usr/bin/gcc";
56        }
57        push(@args, qw(-E -P -x c++));
58    }
59
60    # Remove double quotations from $defines and extract macros.
61    # For example, if $defines is ' "A=1" "B=1" C=1 ""    D  ',
62    # then it is converted into four macros -DA=1, -DB=1, -DC=1 and -DD.
63    $defines =~ s/\"//g;
64    my @macros = grep { $_ } split(/\s+/, $defines); # grep skips empty macros.
65    @macros = map { "-D$_" } @macros;
66
67    my $pid = 0;
68    if ($Config{osname} eq "cygwin" || $Config{osname} eq 'MSWin32') {
69        # This call can fail if Windows rebases cygwin, so retry a few times until it succeeds.
70        for (my $tries = 0; !$pid && ($tries < 20); $tries++) {
71            eval {
72                # Suppress STDERR so that if we're using cl.exe, the output
73                # name isn't needlessly echoed.
74                use Symbol 'gensym'; my $err = gensym;
75                $pid = open3(\*PP_IN, \*PP_OUT, $err, split(' ', $preprocessor), @args, @macros, $fileName);
76                1;
77            } or do {
78                sleep 1;
79            }
80        };
81    } else {
82        $pid = open2(\*PP_OUT, \*PP_IN, split(' ', $preprocessor), @args, @macros, $fileName);
83    }
84    close PP_IN;
85    my @documentContent = <PP_OUT>;
86    close PP_OUT;
87    waitpid($pid, 0);
88    return @documentContent;
89}
90
911;
92