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 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 [-t|--tool=<tool>] [-x|--extcmd=<cmd>]
  27                    [-y|--no-prompt]   [-g|--gui]
  28                    ['git diff' options]
  29USAGE
  30        exit 1;
  31}
  32
  33sub setup_environment
  34{
  35        $ENV{PATH} = "$DIR:$ENV{PATH}";
  36        $ENV{GIT_PAGER} = '';
  37        $ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
  38}
  39
  40sub exe
  41{
  42        my $exe = shift;
  43        if ($^O eq 'MSWin32' || $^O eq 'msys') {
  44                return "$exe.exe";
  45        }
  46        return $exe;
  47}
  48
  49sub generate_command
  50{
  51        my @command = (exe('git'), 'diff');
  52        my $skip_next = 0;
  53        my $idx = -1;
  54        for my $arg (@ARGV) {
  55                $idx++;
  56                if ($skip_next) {
  57                        $skip_next = 0;
  58                        next;
  59                }
  60                if ($arg eq '-t' || $arg eq '--tool') {
  61                        usage() if $#ARGV <= $idx;
  62                        $ENV{GIT_DIFF_TOOL} = $ARGV[$idx + 1];
  63                        $skip_next = 1;
  64                        next;
  65                }
  66                if ($arg =~ /^--tool=/) {
  67                        $ENV{GIT_DIFF_TOOL} = substr($arg, 7);
  68                        next;
  69                }
  70                if ($arg eq '-x' || $arg eq '--extcmd') {
  71                        usage() if $#ARGV <= $idx;
  72                        $ENV{GIT_DIFFTOOL_EXTCMD} = $ARGV[$idx + 1];
  73                        $skip_next = 1;
  74                        next;
  75                }
  76                if ($arg =~ /^--extcmd=/) {
  77                        $ENV{GIT_DIFFTOOL_EXTCMD} = substr($arg, 9);
  78                        next;
  79                }
  80                if ($arg eq '-g' || $arg eq '--gui') {
  81                        eval {
  82                                my $tool = Git::command_oneline('config',
  83                                                                'diff.guitool');
  84                                if (length($tool)) {
  85                                        $ENV{GIT_DIFF_TOOL} = $tool;
  86                                }
  87                        };
  88                        next;
  89                }
  90                if ($arg eq '-y' || $arg eq '--no-prompt') {
  91                        $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
  92                        delete $ENV{GIT_DIFFTOOL_PROMPT};
  93                        next;
  94                }
  95                if ($arg eq '--prompt') {
  96                        $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
  97                        delete $ENV{GIT_DIFFTOOL_NO_PROMPT};
  98                        next;
  99                }
 100                if ($arg eq '-h' || $arg eq '--help') {
 101                        usage();
 102                }
 103                push @command, $arg;
 104        }
 105        return @command
 106}
 107
 108setup_environment();
 109
 110# ActiveState Perl for Win32 does not implement POSIX semantics of
 111# exec* system call. It just spawns the given executable and finishes
 112# the starting program, exiting with code 0.
 113# system will at least catch the errors returned by git diff,
 114# allowing the caller of git difftool better handling of failures.
 115my $rc = system(generate_command());
 116exit($rc | ($rc >> 8));