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        my $prompt = '';
  56        for my $arg (@ARGV) {
  57                $idx++;
  58                if ($skip_next) {
  59                        $skip_next = 0;
  60                        next;
  61                }
  62                if ($arg eq '-t' || $arg eq '--tool') {
  63                        usage() if $#ARGV <= $idx;
  64                        $ENV{GIT_DIFF_TOOL} = $ARGV[$idx + 1];
  65                        $skip_next = 1;
  66                        next;
  67                }
  68                if ($arg =~ /^--tool=/) {
  69                        $ENV{GIT_DIFF_TOOL} = substr($arg, 7);
  70                        next;
  71                }
  72                if ($arg eq '-x' || $arg eq '--extcmd') {
  73                        usage() if $#ARGV <= $idx;
  74                        $ENV{GIT_DIFFTOOL_EXTCMD} = $ARGV[$idx + 1];
  75                        $skip_next = 1;
  76                        next;
  77                }
  78                if ($arg =~ /^--extcmd=/) {
  79                        $ENV{GIT_DIFFTOOL_EXTCMD} = substr($arg, 9);
  80                        next;
  81                }
  82                if ($arg eq '-g' || $arg eq '--gui') {
  83                        eval {
  84                                my $tool = Git::command_oneline('config',
  85                                                                'diff.guitool');
  86                                if (length($tool)) {
  87                                        $ENV{GIT_DIFF_TOOL} = $tool;
  88                                }
  89                        };
  90                        next;
  91                }
  92                if ($arg eq '-y' || $arg eq '--no-prompt') {
  93                        $prompt = 'no';
  94                        next;
  95                }
  96                if ($arg eq '--prompt') {
  97                        $prompt = 'yes';
  98                        next;
  99                }
 100                if ($arg eq '-h' || $arg eq '--help') {
 101                        usage();
 102                }
 103                push @command, $arg;
 104        }
 105        if ($prompt eq 'yes') {
 106                $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
 107        } elsif ($prompt eq 'no') {
 108                $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
 109        }
 110        return @command
 111}
 112
 113setup_environment();
 114
 115# ActiveState Perl for Win32 does not implement POSIX semantics of
 116# exec* system call. It just spawns the given executable and finishes
 117# the starting program, exiting with code 0.
 118# system will at least catch the errors returned by git diff,
 119# allowing the caller of git difftool better handling of failures.
 120my $rc = system(generate_command());
 121exit($rc | ($rc >> 8));