Merge branch 'maint'
[git/spearce.git] / git-difftool.perl
blobba5e60a45e2c4a8b54e6a58e656b3978dcb45633
1 #!/usr/bin/env perl
2 # Copyright (c) 2009 David Aguilar
4 # This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
5 # git-difftool--helper script.
7 # This script exports GIT_EXTERNAL_DIFF and GIT_PAGER for use by git.
8 # GIT_DIFFTOOL_NO_PROMPT, GIT_DIFFTOOL_PROMPT, and GIT_DIFF_TOOL
9 # are exported for use by git-difftool--helper.
11 # Any arguments that are unknown to this script are forwarded to 'git diff'.
13 use strict;
14 use warnings;
15 use Cwd qw(abs_path);
16 use File::Basename qw(dirname);
18 my $DIR = abs_path(dirname($0));
21 sub usage
23 print << 'USAGE';
24 usage: git difftool [--tool=<tool>] [-y|--no-prompt] ["git diff" options]
25 USAGE
26 exit 1;
29 sub setup_environment
31 $ENV{PATH} = "$DIR:$ENV{PATH}";
32 $ENV{GIT_PAGER} = '';
33 $ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
36 sub exe
38 my $exe = shift;
39 if ($^O eq 'MSWin32' || $^O eq 'msys') {
40 return "$exe.exe";
42 return $exe;
45 sub generate_command
47 my @command = (exe('git'), 'diff');
48 my $skip_next = 0;
49 my $idx = -1;
50 for my $arg (@ARGV) {
51 $idx++;
52 if ($skip_next) {
53 $skip_next = 0;
54 next;
56 if ($arg eq '-t' || $arg eq '--tool') {
57 usage() if $#ARGV <= $idx;
58 $ENV{GIT_DIFF_TOOL} = $ARGV[$idx + 1];
59 $skip_next = 1;
60 next;
62 if ($arg =~ /^--tool=/) {
63 $ENV{GIT_DIFF_TOOL} = substr($arg, 7);
64 next;
66 if ($arg eq '-y' || $arg eq '--no-prompt') {
67 $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
68 delete $ENV{GIT_DIFFTOOL_PROMPT};
69 next;
71 if ($arg eq '--prompt') {
72 $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
73 delete $ENV{GIT_DIFFTOOL_NO_PROMPT};
74 next;
76 if ($arg eq '-h' || $arg eq '--help') {
77 usage();
79 push @command, $arg;
81 return @command
84 setup_environment();
86 # ActiveState Perl for Win32 does not implement POSIX semantics of
87 # exec* system call. It just spawns the given executable and finishes
88 # the starting program, exiting with code 0.
89 # system will at least catch the errors returned by git diff,
90 # allowing the caller of git difftool better handling of failures.
91 my $rc = system(generate_command());
92 exit($rc | ($rc >> 8));