Andrew's git - gitweb.git/blob

   1#!/usr/bin/env perl
   2# Copyright (c) 2009, 2010 David Aguilar
   3#
   4# This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
   5# git-difftool--helper script.
   6#
   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.
  10#
  11# Any arguments that are unknown to this script are forwarded to 'git diff'.
  12
  13use 5.008;
  14use strict;
  15use warnings;
  16use Cwd qw(abs_path);
  17use File::Basename qw(dirname);
  18
  19require Git;
  20
  21my $DIR = abs_path(dirname($0));
  22
  23
  24sub usage
  25{
  26        print << 'USAGE';
  27usage: git difftool [-t|--tool=<tool>] [-x|--extcmd=<cmd>]
  28                    [-y|--no-prompt]   [-g|--gui]
  29                    ['git diff' options]
  30USAGE
  31        exit 1;
  32}
  33
  34sub setup_environment
  35{
  36        $ENV{PATH} = "$DIR:$ENV{PATH}";
  37        $ENV{GIT_PAGER} = '';
  38        $ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
  39}
  40
  41sub exe
  42{
  43        my $exe = shift;
  44        if ($^O eq 'MSWin32' || $^O eq 'msys') {
  45                return "$exe.exe";
  46        }
  47        return $exe;
  48}
  49
  50sub generate_command
  51{
  52        my @command = (exe('git'), 'diff');
  53        my $skip_next = 0;
  54        my $idx = -1;
  55        for my $arg (@ARGV) {
  56                $idx++;
  57                if ($skip_next) {
  58                        $skip_next = 0;
  59                        next;
  60                }
  61                if ($arg eq '-t' || $arg eq '--tool') {
  62                        usage() if $#ARGV <= $idx;
  63                        $ENV{GIT_DIFF_TOOL} = $ARGV[$idx + 1];
  64                        $skip_next = 1;
  65                        next;
  66                }
  67                if ($arg =~ /^--tool=/) {
  68                        $ENV{GIT_DIFF_TOOL} = substr($arg, 7);
  69                        next;
  70                }
  71                if ($arg eq '-x' || $arg eq '--extcmd') {
  72                        usage() if $#ARGV <= $idx;
  73                        $ENV{GIT_DIFFTOOL_EXTCMD} = $ARGV[$idx + 1];
  74                        $skip_next = 1;
  75                        next;
  76                }
  77                if ($arg =~ /^--extcmd=/) {
  78                        $ENV{GIT_DIFFTOOL_EXTCMD} = substr($arg, 9);
  79                        next;
  80                }
  81                if ($arg eq '-g' || $arg eq '--gui') {
  82                        eval {
  83                                my $tool = Git::command_oneline('config',
  84                                                                'diff.guitool');
  85                                if (length($tool)) {
  86                                        $ENV{GIT_DIFF_TOOL} = $tool;
  87                                }
  88                        };
  89                        next;
  90                }
  91                if ($arg eq '-y' || $arg eq '--no-prompt') {
  92                        $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
  93                        delete $ENV{GIT_DIFFTOOL_PROMPT};
  94                        next;
  95                }
  96                if ($arg eq '--prompt') {
  97                        $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
  98                        delete $ENV{GIT_DIFFTOOL_NO_PROMPT};
  99                        next;
 100                }
 101                if ($arg eq '-h' || $arg eq '--help') {
 102                        usage();
 103                }
 104                push @command, $arg;
 105        }
 106        return @command
 107}
 108
 109setup_environment();
 110
 111# ActiveState Perl for Win32 does not implement POSIX semantics of
 112# exec* system call. It just spawns the given executable and finishes
 113# the starting program, exiting with code 0.
 114# system will at least catch the errors returned by git diff,
 115# allowing the caller of git difftool better handling of failures.
 116my $rc = system(generate_command());
 117exit($rc | ($rc >> 8));