Merge remote-tracking branch 'ko/maint' into jc/diff-index-quick-exit-early

* ko/maint: (4352 commits)
  git-submodule.sh: separate parens by a space to avoid confusing some shells
  Documentation/technical/api-diff.txt: correct name of diff_unmerge()
  read_gitfile_gently: use ssize_t to hold read result
  remove tests of always-false condition
  rerere.c: diagnose a corrupt MERGE_RR when hitting EOF between TAB and '\0'
  Git 1.7.5.3
  init/clone: remove short option -L and document --separate-git-dir
  do not read beyond end of malloc'd buffer
  git-svn: Fix git svn log --show-commit
  Git 1.7.5.2
  provide a copy of the LGPLv2.1
  test core.gitproxy configuration
  copy_gecos: fix not adding nlen to len when processing "&"
  Update draft release notes to 1.7.5.2
  Documentation/git-fsck.txt: fix typo: unreadable -> unreachable
  send-pack: avoid deadlock on git:// push with failed pack-objects
  connect: let callers know if connection is a socket
  connect: treat generic proxy processes like ssh processes
  sideband_demux(): fix decl-after-stmt
  t3503: test cherry picking and reverting root commits
  ...

Conflicts:
	diff.c

1 files changed, 35 insertions, 6 deletions

diff --git a/git-difftool.perl b/git-difftool.perl
index ba5e60a45e..ced1615e21 100755
--- a/git-difftool.perl
+++ b/git-difftool.perl
@@ -1,5 +1,5 @@
 #!/usr/bin/env perl
-# Copyright (c) 2009 David Aguilar
+# Copyright (c) 2009, 2010 David Aguilar
 #
 # This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
 # git-difftool--helper script.
@@ -10,18 +10,23 @@
 #
 # Any arguments that are unknown to this script are forwarded to 'git diff'.
 
+use 5.008;
 use strict;
 use warnings;
 use Cwd qw(abs_path);
 use File::Basename qw(dirname);
 
+require Git;
+
 my $DIR = abs_path(dirname($0));
 
 
 sub usage
 {
 	print << 'USAGE';
-usage: git difftool [--tool=<tool>] [-y|--no-prompt] ["git diff" options]
+usage: git difftool [-t|--tool=<tool>] [-x|--extcmd=<cmd>]
+                    [-y|--no-prompt]   [-g|--gui]
+                    ['git diff' options]
 USAGE
 	exit 1;
 }
@@ -47,6 +52,7 @@ sub generate_command
 	my @command = (exe('git'), 'diff');
 	my $skip_next = 0;
 	my $idx = -1;
+	my $prompt = '';
 	for my $arg (@ARGV) {
 		$idx++;
 		if ($skip_next) {
@@ -63,14 +69,32 @@ sub generate_command
 			$ENV{GIT_DIFF_TOOL} = substr($arg, 7);
 			next;
 		}
+		if ($arg eq '-x' || $arg eq '--extcmd') {
+			usage() if $#ARGV <= $idx;
+			$ENV{GIT_DIFFTOOL_EXTCMD} = $ARGV[$idx + 1];
+			$skip_next = 1;
+			next;
+		}
+		if ($arg =~ /^--extcmd=/) {
+			$ENV{GIT_DIFFTOOL_EXTCMD} = substr($arg, 9);
+			next;
+		}
+		if ($arg eq '-g' || $arg eq '--gui') {
+			eval {
+				my $tool = Git::command_oneline('config',
+				                                'diff.guitool');
+				if (length($tool)) {
+					$ENV{GIT_DIFF_TOOL} = $tool;
+				}
+			};
+			next;
+		}
 		if ($arg eq '-y' || $arg eq '--no-prompt') {
-			$ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
-			delete $ENV{GIT_DIFFTOOL_PROMPT};
+			$prompt = 'no';
 			next;
 		}
 		if ($arg eq '--prompt') {
-			$ENV{GIT_DIFFTOOL_PROMPT} = 'true';
-			delete $ENV{GIT_DIFFTOOL_NO_PROMPT};
+			$prompt = 'yes';
 			next;
 		}
 		if ($arg eq '-h' || $arg eq '--help') {
@@ -78,6 +102,11 @@ sub generate_command
 		}
 		push @command, $arg;
 	}
+	if ($prompt eq 'yes') {
+		$ENV{GIT_DIFFTOOL_PROMPT} = 'true';
+	} elsif ($prompt eq 'no') {
+		$ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
+	}
 	return @command
 }