Andrew's git - gitweb.git/blob

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