[thirdparty/git.git] / git-difftool.perl

#!/usr/bin/perl
# Copyright (c) 2009, 2010 David Aguilar
# Copyright (c) 2012 Tim Henigan
#
# This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
# git-difftool--helper script.
#
# This script exports GIT_EXTERNAL_DIFF and GIT_PAGER for use by git.
# The GIT_DIFF* variables are exported for use by git-difftool--helper.
#
# Any arguments that are unknown to this script are forwarded to 'git diff'.

use 5.008;
use strict;
use warnings;
use Error qw(:try);
use File::Basename qw(dirname);
use File::Copy;
use File::Find;
use File::stat;
use File::Path qw(mkpath rmtree);
use File::Temp qw(tempdir);
use Getopt::Long qw(:config pass_through);
use Git;

sub usage
{
	my $exitcode = shift;
	print << 'USAGE';
usage: git difftool [-t|--tool=<tool>] [--tool-help]
                    [-x|--extcmd=<cmd>]
                    [-g|--gui] [--no-gui]
                    [--prompt] [-y|--no-prompt]
                    [-d|--dir-diff]
                    ['git diff' options]
USAGE
	exit($exitcode);
}

sub find_worktree
{
	# Git->repository->wc_path() does not honor changes to the working
	# tree location made by $ENV{GIT_WORK_TREE} or the 'core.worktree'
	# config variable.
	return Git::command_oneline('rev-parse', '--show-toplevel');
}

sub print_tool_help
{
	my $cmd = 'TOOL_MODE=diff';
	$cmd .= ' && . "$(git --exec-path)/git-mergetool--lib"';
	$cmd .= ' && show_tool_help';

	# See the comment at the bottom of file_diff() for the reason behind
	# using system() followed by exit() instead of exec().
	my $rc = system('sh', '-c', $cmd);
	exit($rc | ($rc >> 8));
}

sub exit_cleanup
{
	my ($tmpdir, $status) = @_;
	my $errno = $!;
	rmtree($tmpdir);
	if ($status and $errno) {
		my ($package, $file, $line) = caller();
		warn "$file line $line: $errno\n";
	}
	exit($status | ($status >> 8));
}

sub use_wt_file
{
	my ($repo, $workdir, $file, $sha1) = @_;
	my $null_sha1 = '0' x 40;

	if (! -e "$workdir/$file") {
		# If the file doesn't exist in the working tree, we cannot
		# use it.
		return (0, $null_sha1);
	}

	my $wt_sha1 = $repo->command_oneline('hash-object', "$workdir/$file");
	my $use = ($sha1 eq $null_sha1) || ($sha1 eq $wt_sha1);
	return ($use, $wt_sha1);
}

sub changed_files
{
	my ($repo_path, $index, $worktree) = @_;
	$ENV{GIT_INDEX_FILE} = $index;
	$ENV{GIT_WORK_TREE} = $worktree;
	my $must_unset_git_dir = 0;
	if (not defined($ENV{GIT_DIR})) {
		$must_unset_git_dir = 1;
		$ENV{GIT_DIR} = $repo_path;
	}

	my @refreshargs = qw/update-index --really-refresh -q --unmerged/;
	my @gitargs = qw/diff-files --name-only -z/;
	try {
		Git::command_oneline(@refreshargs);
	} catch Git::Error::Command with {};

	my $line = Git::command_oneline(@gitargs);
	my @files;
	if (defined $line) {
		@files = split('\0', $line);
	} else {
		@files = ();
	}

	delete($ENV{GIT_INDEX_FILE});
	delete($ENV{GIT_WORK_TREE});
	delete($ENV{GIT_DIR}) if ($must_unset_git_dir);

	return map { $_ => 1 } @files;
}

sub setup_dir_diff
{
	my ($repo, $workdir, $symlinks) = @_;

	# Run the diff; exit immediately if no diff found
	# 'Repository' and 'WorkingCopy' must be explicitly set to insure that
	# if $GIT_DIR and $GIT_WORK_TREE are set in ENV, they are actually used
	# by Git->repository->command*.
	my $repo_path = $repo->repo_path();
	my %repo_args = (Repository => $repo_path, WorkingCopy => $workdir);
	my $diffrepo = Git->repository(%repo_args);

	my @gitargs = ('diff', '--raw', '--no-abbrev', '-z', @ARGV);
	my $diffrtn = $diffrepo->command_oneline(@gitargs);
	exit(0) unless defined($diffrtn);

	# Build index info for left and right sides of the diff
	my $submodule_mode = '160000';
	my $symlink_mode = '120000';
	my $null_mode = '0' x 6;
	my $null_sha1 = '0' x 40;
	my $lindex = '';
	my $rindex = '';
	my $wtindex = '';
	my %submodule;
	my %symlink;
	my @working_tree = ();
	my @rawdiff = split('\0', $diffrtn);

	my $i = 0;
	while ($i < $#rawdiff) {
		if ($rawdiff[$i] =~ /^::/) {
			warn << 'EOF';
Combined diff formats ('-c' and '--cc') are not supported in
directory diff mode ('-d' and '--dir-diff').
EOF
			exit(1);
		}

		my ($lmode, $rmode, $lsha1, $rsha1, $status) =
			split(' ', substr($rawdiff[$i], 1));
		my $src_path = $rawdiff[$i + 1];
		my $dst_path;

		if ($status =~ /^[CR]/) {
			$dst_path = $rawdiff[$i + 2];
			$i += 3;
		} else {
			$dst_path = $src_path;
			$i += 2;
		}

		if ($lmode eq $submodule_mode or $rmode eq $submodule_mode) {
			$submodule{$src_path}{left} = $lsha1;
			if ($lsha1 ne $rsha1) {
				$submodule{$dst_path}{right} = $rsha1;
			} else {
				$submodule{$dst_path}{right} = "$rsha1-dirty";
			}
			next;
		}

		if ($lmode eq $symlink_mode) {
			$symlink{$src_path}{left} =
				$diffrepo->command_oneline('show', "$lsha1");
		}

		if ($rmode eq $symlink_mode) {
			$symlink{$dst_path}{right} =
				$diffrepo->command_oneline('show', "$rsha1");
		}

		if ($lmode ne $null_mode and $status !~ /^C/) {
			$lindex .= "$lmode $lsha1\t$src_path\0";
		}

		if ($rmode ne $null_mode) {
			my ($use, $wt_sha1) = use_wt_file($repo, $workdir,
							  $dst_path, $rsha1);
			if ($use) {
				push @working_tree, $dst_path;
				$wtindex .= "$rmode $wt_sha1\t$dst_path\0";
			} else {
				$rindex .= "$rmode $rsha1\t$dst_path\0";
			}
		}
	}

	# Setup temp directories
	my $tmpdir = tempdir('git-difftool.XXXXX', CLEANUP => 0, TMPDIR => 1);
	my $ldir = "$tmpdir/left";
	my $rdir = "$tmpdir/right";
	mkpath($ldir) or exit_cleanup($tmpdir, 1);
	mkpath($rdir) or exit_cleanup($tmpdir, 1);

	# If $GIT_DIR is not set prior to calling 'git update-index' and
	# 'git checkout-index', then those commands will fail if difftool
	# is called from a directory other than the repo root.
	my $must_unset_git_dir = 0;
	if (not defined($ENV{GIT_DIR})) {
		$must_unset_git_dir = 1;
		$ENV{GIT_DIR} = $repo_path;
	}

	# Populate the left and right directories based on each index file
	my ($inpipe, $ctx);
	$ENV{GIT_INDEX_FILE} = "$tmpdir/lindex";
	($inpipe, $ctx) =
		$repo->command_input_pipe(qw(update-index -z --index-info));
	print($inpipe $lindex);
	$repo->command_close_pipe($inpipe, $ctx);

	my $rc = system('git', 'checkout-index', '--all', "--prefix=$ldir/");
	exit_cleanup($tmpdir, $rc) if $rc != 0;

	$ENV{GIT_INDEX_FILE} = "$tmpdir/rindex";
	($inpipe, $ctx) =
		$repo->command_input_pipe(qw(update-index -z --index-info));
	print($inpipe $rindex);
	$repo->command_close_pipe($inpipe, $ctx);

	$rc = system('git', 'checkout-index', '--all', "--prefix=$rdir/");
	exit_cleanup($tmpdir, $rc) if $rc != 0;

	$ENV{GIT_INDEX_FILE} = "$tmpdir/wtindex";
	($inpipe, $ctx) =
		$repo->command_input_pipe(qw(update-index --info-only -z --index-info));
	print($inpipe $wtindex);
	$repo->command_close_pipe($inpipe, $ctx);

	# If $GIT_DIR was explicitly set just for the update/checkout
	# commands, then it should be unset before continuing.
	delete($ENV{GIT_DIR}) if ($must_unset_git_dir);
	delete($ENV{GIT_INDEX_FILE});

	# Changes in the working tree need special treatment since they are
	# not part of the index. Remove any trailing slash from $workdir
	# before starting to avoid double slashes in symlink targets.
	$workdir =~ s|/$||;
	for my $file (@working_tree) {
		my $dir = dirname($file);
		unless (-d "$rdir/$dir") {
			mkpath("$rdir/$dir") or
			exit_cleanup($tmpdir, 1);
		}
		if ($symlinks) {
			symlink("$workdir/$file", "$rdir/$file") or
			exit_cleanup($tmpdir, 1);
		} else {
			copy("$workdir/$file", "$rdir/$file") or
			exit_cleanup($tmpdir, 1);

			my $mode = stat("$workdir/$file")->mode;
			chmod($mode, "$rdir/$file") or
			exit_cleanup($tmpdir, 1);
		}
	}

	# Changes to submodules require special treatment. This loop writes a
	# temporary file to both the left and right directories to show the
	# change in the recorded SHA1 for the submodule.
	for my $path (keys %submodule) {
		my $ok;
		if (defined($submodule{$path}{left})) {
			$ok = write_to_file("$ldir/$path",
				"Subproject commit $submodule{$path}{left}");
		}
		if (defined($submodule{$path}{right})) {
			$ok = write_to_file("$rdir/$path",
				"Subproject commit $submodule{$path}{right}");
		}
		exit_cleanup($tmpdir, 1) if not $ok;
	}

	# Symbolic links require special treatment. The standard "git diff"
	# shows only the link itself, not the contents of the link target.
	# This loop replicates that behavior.
	for my $path (keys %symlink) {
		my $ok;
		if (defined($symlink{$path}{left})) {
			$ok = write_to_file("$ldir/$path",
					$symlink{$path}{left});
		}
		if (defined($symlink{$path}{right})) {
			$ok = write_to_file("$rdir/$path",
					$symlink{$path}{right});
		}
		exit_cleanup($tmpdir, 1) if not $ok;
	}

	return ($ldir, $rdir, $tmpdir, @working_tree);
}

sub write_to_file
{
	my $path = shift;
	my $value = shift;

	# Make sure the path to the file exists
	my $dir = dirname($path);
	unless (-d "$dir") {
		mkpath("$dir") or return 0;
	}

	# If the file already exists in that location, delete it.  This
	# is required in the case of symbolic links.
	unlink($path);

	open(my $fh, '>', $path) or return 0;
	print($fh $value);
	close($fh);

	return 1;
}

sub main
{
	# parse command-line options. all unrecognized options and arguments
	# are passed through to the 'git diff' command.
	my %opts = (
		difftool_cmd => undef,
		dirdiff => undef,
		extcmd => undef,
		gui => undef,
		help => undef,
		prompt => undef,
		symlinks => $^O ne 'cygwin' &&
				$^O ne 'MSWin32' && $^O ne 'msys',
		tool_help => undef,
	);
	GetOptions('g|gui!' => \$opts{gui},
		'd|dir-diff' => \$opts{dirdiff},
		'h' => \$opts{help},
		'prompt!' => \$opts{prompt},
		'y' => sub { $opts{prompt} = 0; },
		'symlinks' => \$opts{symlinks},
		'no-symlinks' => sub { $opts{symlinks} = 0; },
		't|tool:s' => \$opts{difftool_cmd},
		'tool-help' => \$opts{tool_help},
		'x|extcmd:s' => \$opts{extcmd});

	if (defined($opts{help})) {
		usage(0);
	}
	if (defined($opts{tool_help})) {
		print_tool_help();
	}
	if (defined($opts{difftool_cmd})) {
		if (length($opts{difftool_cmd}) > 0) {
			$ENV{GIT_DIFF_TOOL} = $opts{difftool_cmd};
		} else {
			print "No <tool> given for --tool=<tool>\n";
			usage(1);
		}
	}
	if (defined($opts{extcmd})) {
		if (length($opts{extcmd}) > 0) {
			$ENV{GIT_DIFFTOOL_EXTCMD} = $opts{extcmd};
		} else {
			print "No <cmd> given for --extcmd=<cmd>\n";
			usage(1);
		}
	}
	if ($opts{gui}) {
		my $guitool = Git::config('diff.guitool');
		if (defined($guitool) && length($guitool) > 0) {
			$ENV{GIT_DIFF_TOOL} = $guitool;
		}
	}

	# In directory diff mode, 'git-difftool--helper' is called once
	# to compare the a/b directories.  In file diff mode, 'git diff'
	# will invoke a separate instance of 'git-difftool--helper' for
	# each file that changed.
	if (defined($opts{dirdiff})) {
		dir_diff($opts{extcmd}, $opts{symlinks});
	} else {
		file_diff($opts{prompt});
	}
}

sub dir_diff
{
	my ($extcmd, $symlinks) = @_;
	my $rc;
	my $error = 0;
	my $repo = Git->repository();
	my $workdir = find_worktree();
	my ($a, $b, $tmpdir, @worktree) =
		setup_dir_diff($repo, $workdir, $symlinks);

	if (defined($extcmd)) {
		$rc = system($extcmd, $a, $b);
	} else {
		$ENV{GIT_DIFFTOOL_DIRDIFF} = 'true';
		$rc = system('git', 'difftool--helper', $a, $b);
	}
	# If the diff including working copy files and those
	# files were modified during the diff, then the changes
	# should be copied back to the working tree.
	# Do not copy back files when symlinks are used and the
	# external tool did not replace the original link with a file.
	#
	# These hashes are loaded lazily since they aren't needed
	# in the common case of --symlinks and the difftool updating
	# files through the symlink.
	my %wt_modified;
	my %tmp_modified;
	my $indices_loaded = 0;

	for my $file (@worktree) {
		next if $symlinks && -l "$b/$file";
		next if ! -f "$b/$file";

		if (!$indices_loaded) {
			%wt_modified = changed_files($repo->repo_path(),
				"$tmpdir/wtindex", "$workdir");
			%tmp_modified = changed_files($repo->repo_path(),
				"$tmpdir/wtindex", "$b");
			$indices_loaded = 1;
		}

		if (exists $wt_modified{$file} and exists $tmp_modified{$file}) {
			my $errmsg = "warning: Both files modified: ";
			$errmsg .= "'$workdir/$file' and '$b/$file'.\n";
			$errmsg .= "warning: Working tree file has been left.\n";
			$errmsg .= "warning:\n";
			warn $errmsg;
			$error = 1;
		} elsif (exists $tmp_modified{$file}) {
			my $mode = stat("$b/$file")->mode;
			copy("$b/$file", "$workdir/$file") or
			exit_cleanup($tmpdir, 1);

			chmod($mode, "$workdir/$file") or
			exit_cleanup($tmpdir, 1);
		}
	}
	if ($error) {
		warn "warning: Temporary files exist in '$tmpdir'.\n";
		warn "warning: You may want to cleanup or recover these.\n";
		exit(1);
	} else {
		exit_cleanup($tmpdir, $rc);
	}
}

sub file_diff
{
	my ($prompt) = @_;

	if (defined($prompt)) {
		if ($prompt) {
			$ENV{GIT_DIFFTOOL_PROMPT} = 'true';
		} else {
			$ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
		}
	}

	$ENV{GIT_PAGER} = '';
	$ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';

	# ActiveState Perl for Win32 does not implement POSIX semantics of
	# exec* system call. It just spawns the given executable and finishes
	# the starting program, exiting with code 0.
	# system will at least catch the errors returned by git diff,
	# allowing the caller of git difftool better handling of failures.
	my $rc = system('git', 'diff', @ARGV);
	exit($rc | ($rc >> 8));
}

main();
Commit	Line	Data
7e0abcec	1	#!/usr/bin/perl
f47f1e2c	2	# Copyright (c) 2009, 2010 David Aguilar
7e0abcec	3	# Copyright (c) 2012 Tim Henigan
5c38ea31 DA	4	#
5c38ea31 DA	5	# This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
a904392e DA	6	# git-difftool--helper script.
	7	#
	8	# This script exports GIT_EXTERNAL_DIFF and GIT_PAGER for use by git.
7e0abcec	9	# The GIT_DIFF* variables are exported for use by git-difftool--helper.
a904392e	10	#
5c38ea31 DA	11	# Any arguments that are unknown to this script are forwarded to 'git diff'.
5c38ea31 DA	12
d48b2841	13	use 5.008;
5c38ea31 DA	14	use strict;
5c38ea31 DA	15	use warnings;
67aa147a	16	use Error qw(:try);
7c7584b9	17	use File::Basename qw(dirname);
7e0abcec	18	use File::Copy;
7c7584b9	19	use File::Find;
7e0abcec	20	use File::stat;
ceb1497a	21	use File::Path qw(mkpath rmtree);
7e0abcec	22	use File::Temp qw(tempdir);
3f94ff75 TH	23	use Getopt::Long qw(:config pass_through);
3f94ff75 TH	24	use Git;
5c38ea31 DA	25
	26	sub usage
	27	{
28360769	28	my $exitcode = shift;
5c38ea31	29	print << 'USAGE';
bf73fc21	30	usage: git difftool [-t\|--tool=<tool>] [--tool-help]
85089604 TH	31	[-x\|--extcmd=<cmd>]
85089604 TH	32	[-g\|--gui] [--no-gui]
3f94ff75	33	[--prompt] [-y\|--no-prompt]
7e0abcec	34	[-d\|--dir-diff]
f47f1e2c	35	['git diff' options]
5c38ea31	36	USAGE
28360769	37	exit($exitcode);
5c38ea31 DA	38	}
5c38ea31 DA	39
7e0abcec TH	40	sub find_worktree
	41	{
	42	# Git->repository->wc_path() does not honor changes to the working
	43	# tree location made by $ENV{GIT_WORK_TREE} or the 'core.worktree'
	44	# config variable.
94eaa806	45	return Git::command_oneline('rev-parse', '--show-toplevel');
7e0abcec TH	46	}
7e0abcec TH	47
bf73fc21 TH	48	sub print_tool_help
bf73fc21 TH	49	{
abaf175c JK	50	my $cmd = 'TOOL_MODE=diff';
	51	$cmd .= ' && . "$(git --exec-path)/git-mergetool--lib"';
	52	$cmd .= ' && show_tool_help';
	53
	54	# See the comment at the bottom of file_diff() for the reason behind
	55	# using system() followed by exit() instead of exec().
	56	my $rc = system('sh', '-c', $cmd);
	57	exit($rc \| ($rc >> 8));
bf73fc21 TH	58	}
bf73fc21 TH	59
ceb1497a DA	60	sub exit_cleanup
	61	{
	62	my ($tmpdir, $status) = @_;
	63	my $errno = $!;
	64	rmtree($tmpdir);
	65	if ($status and $errno) {
	66	my ($package, $file, $line) = caller();
	67	warn "$file line $line: $errno\n";
	68	}
	69	exit($status \| ($status >> 8));
	70	}
	71
02c56314 JK	72	sub use_wt_file
02c56314 JK	73	{
32eaf1de	74	my ($repo, $workdir, $file, $sha1) = @_;
02c56314 JK	75	my $null_sha1 = '0' x 40;
02c56314 JK	76
1f197a1d JK	77	if (! -e "$workdir/$file") {
	78	# If the file doesn't exist in the working tree, we cannot
	79	# use it.
	80	return (0, $null_sha1);
	81	}
	82
02c56314	83	my $wt_sha1 = $repo->command_oneline('hash-object', "$workdir/$file");
67aa147a JK	84	my $use = ($sha1 eq $null_sha1) \|\| ($sha1 eq $wt_sha1);
	85	return ($use, $wt_sha1);
	86	}
	87
	88	sub changed_files
	89	{
	90	my ($repo_path, $index, $worktree) = @_;
	91	$ENV{GIT_INDEX_FILE} = $index;
	92	$ENV{GIT_WORK_TREE} = $worktree;
	93	my $must_unset_git_dir = 0;
	94	if (not defined($ENV{GIT_DIR})) {
	95	$must_unset_git_dir = 1;
	96	$ENV{GIT_DIR} = $repo_path;
	97	}
	98
	99	my @refreshargs = qw/update-index --really-refresh -q --unmerged/;
	100	my @gitargs = qw/diff-files --name-only -z/;
	101	try {
	102	Git::command_oneline(@refreshargs);
	103	} catch Git::Error::Command with {};
	104
	105	my $line = Git::command_oneline(@gitargs);
	106	my @files;
	107	if (defined $line) {
	108	@files = split('\0', $line);
	109	} else {
	110	@files = ();
	111	}
	112
	113	delete($ENV{GIT_INDEX_FILE});
	114	delete($ENV{GIT_WORK_TREE});
	115	delete($ENV{GIT_DIR}) if ($must_unset_git_dir);
	116
	117	return map { $_ => 1 } @files;
02c56314 JK	118	}
02c56314 JK	119
7e0abcec TH	120	sub setup_dir_diff
7e0abcec TH	121	{
1f229345	122	my ($repo, $workdir, $symlinks) = @_;
75cd7583	123
7e0abcec TH	124	# Run the diff; exit immediately if no diff found
	125	# 'Repository' and 'WorkingCopy' must be explicitly set to insure that
	126	# if $GIT_DIR and $GIT_WORK_TREE are set in ENV, they are actually used
	127	# by Git->repository->command*.
75cd7583	128	my $repo_path = $repo->repo_path();
a4cd5be3 DA	129	my %repo_args = (Repository => $repo_path, WorkingCopy => $workdir);
	130	my $diffrepo = Git->repository(%repo_args);
	131
	132	my @gitargs = ('diff', '--raw', '--no-abbrev', '-z', @ARGV);
	133	my $diffrtn = $diffrepo->command_oneline(@gitargs);
ed36e5bd	134	exit(0) unless defined($diffrtn);
7e0abcec	135
7e0abcec TH	136	# Build index info for left and right sides of the diff
	137	my $submodule_mode = '160000';
	138	my $symlink_mode = '120000';
	139	my $null_mode = '0' x 6;
	140	my $null_sha1 = '0' x 40;
	141	my $lindex = '';
	142	my $rindex = '';
67aa147a	143	my $wtindex = '';
7e0abcec TH	144	my %submodule;
7e0abcec TH	145	my %symlink;
75cd7583	146	my @working_tree = ();
7e0abcec TH	147	my @rawdiff = split('\0', $diffrtn);
	148
	149	my $i = 0;
	150	while ($i < $#rawdiff) {
	151	if ($rawdiff[$i] =~ /^::/) {
a4cd5be3 DA	152	warn << 'EOF';
	153	Combined diff formats ('-c' and '--cc') are not supported in
	154	directory diff mode ('-d' and '--dir-diff').
	155	EOF
7e0abcec TH	156	exit(1);
	157	}
	158
a4cd5be3 DA	159	my ($lmode, $rmode, $lsha1, $rsha1, $status) =
a4cd5be3 DA	160	split(' ', substr($rawdiff[$i], 1));
7e0abcec TH	161	my $src_path = $rawdiff[$i + 1];
	162	my $dst_path;
	163
	164	if ($status =~ /^[CR]/) {
	165	$dst_path = $rawdiff[$i + 2];
	166	$i += 3;
	167	} else {
	168	$dst_path = $src_path;
	169	$i += 2;
	170	}
	171
a4cd5be3	172	if ($lmode eq $submodule_mode or $rmode eq $submodule_mode) {
7e0abcec TH	173	$submodule{$src_path}{left} = $lsha1;
	174	if ($lsha1 ne $rsha1) {
	175	$submodule{$dst_path}{right} = $rsha1;
	176	} else {
	177	$submodule{$dst_path}{right} = "$rsha1-dirty";
	178	}
	179	next;
	180	}
	181
	182	if ($lmode eq $symlink_mode) {
a4cd5be3 DA	183	$symlink{$src_path}{left} =
a4cd5be3 DA	184	$diffrepo->command_oneline('show', "$lsha1");
7e0abcec TH	185	}
	186
	187	if ($rmode eq $symlink_mode) {
a4cd5be3 DA	188	$symlink{$dst_path}{right} =
a4cd5be3 DA	189	$diffrepo->command_oneline('show', "$rsha1");
7e0abcec TH	190	}
7e0abcec TH	191
a4cd5be3	192	if ($lmode ne $null_mode and $status !~ /^C/) {
7e0abcec TH	193	$lindex .= "$lmode $lsha1\t$src_path\0";
	194	}
	195
	196	if ($rmode ne $null_mode) {
67aa147a	197	my ($use, $wt_sha1) = use_wt_file($repo, $workdir,
32eaf1de	198	$dst_path, $rsha1);
67aa147a JK	199	if ($use) {
	200	push @working_tree, $dst_path;
	201	$wtindex .= "$rmode $wt_sha1\t$dst_path\0";
02c56314 JK	202	} else {
02c56314 JK	203	$rindex .= "$rmode $rsha1\t$dst_path\0";
7e0abcec TH	204	}
	205	}
	206	}
	207
ceb1497a DA	208	# Setup temp directories
	209	my $tmpdir = tempdir('git-difftool.XXXXX', CLEANUP => 0, TMPDIR => 1);
	210	my $ldir = "$tmpdir/left";
	211	my $rdir = "$tmpdir/right";
	212	mkpath($ldir) or exit_cleanup($tmpdir, 1);
	213	mkpath($rdir) or exit_cleanup($tmpdir, 1);
	214
7e0abcec TH	215	# If $GIT_DIR is not set prior to calling 'git update-index' and
	216	# 'git checkout-index', then those commands will fail if difftool
	217	# is called from a directory other than the repo root.
	218	my $must_unset_git_dir = 0;
	219	if (not defined($ENV{GIT_DIR})) {
	220	$must_unset_git_dir = 1;
	221	$ENV{GIT_DIR} = $repo_path;
	222	}
	223
	224	# Populate the left and right directories based on each index file
	225	my ($inpipe, $ctx);
	226	$ENV{GIT_INDEX_FILE} = "$tmpdir/lindex";
a4cd5be3 DA	227	($inpipe, $ctx) =
a4cd5be3 DA	228	$repo->command_input_pipe(qw(update-index -z --index-info));
7e0abcec TH	229	print($inpipe $lindex);
7e0abcec TH	230	$repo->command_close_pipe($inpipe, $ctx);
ceb1497a	231
75cd7583	232	my $rc = system('git', 'checkout-index', '--all', "--prefix=$ldir/");
ceb1497a	233	exit_cleanup($tmpdir, $rc) if $rc != 0;
7e0abcec TH	234
7e0abcec TH	235	$ENV{GIT_INDEX_FILE} = "$tmpdir/rindex";
a4cd5be3 DA	236	($inpipe, $ctx) =
a4cd5be3 DA	237	$repo->command_input_pipe(qw(update-index -z --index-info));
7e0abcec TH	238	print($inpipe $rindex);
7e0abcec TH	239	$repo->command_close_pipe($inpipe, $ctx);
ceb1497a	240
7e0abcec	241	$rc = system('git', 'checkout-index', '--all', "--prefix=$rdir/");
ceb1497a	242	exit_cleanup($tmpdir, $rc) if $rc != 0;
7e0abcec	243
67aa147a JK	244	$ENV{GIT_INDEX_FILE} = "$tmpdir/wtindex";
	245	($inpipe, $ctx) =
	246	$repo->command_input_pipe(qw(update-index --info-only -z --index-info));
	247	print($inpipe $wtindex);
	248	$repo->command_close_pipe($inpipe, $ctx);
	249
7e0abcec TH	250	# If $GIT_DIR was explicitly set just for the update/checkout
	251	# commands, then it should be unset before continuing.
	252	delete($ENV{GIT_DIR}) if ($must_unset_git_dir);
	253	delete($ENV{GIT_INDEX_FILE});
	254
	255	# Changes in the working tree need special treatment since they are
e0976dcf JK	256	# not part of the index. Remove any trailing slash from $workdir
	257	# before starting to avoid double slashes in symlink targets.
	258	$workdir =~ s\|/$\|\|;
7e0abcec TH	259	for my $file (@working_tree) {
	260	my $dir = dirname($file);
	261	unless (-d "$rdir/$dir") {
ceb1497a DA	262	mkpath("$rdir/$dir") or
ceb1497a DA	263	exit_cleanup($tmpdir, 1);
7e0abcec	264	}
1f229345	265	if ($symlinks) {
ceb1497a DA	266	symlink("$workdir/$file", "$rdir/$file") or
ceb1497a DA	267	exit_cleanup($tmpdir, 1);
1f229345	268	} else {
ceb1497a DA	269	copy("$workdir/$file", "$rdir/$file") or
	270	exit_cleanup($tmpdir, 1);
	271
1f229345	272	my $mode = stat("$workdir/$file")->mode;
ceb1497a DA	273	chmod($mode, "$rdir/$file") or
ceb1497a DA	274	exit_cleanup($tmpdir, 1);
1f229345	275	}
7e0abcec TH	276	}
	277
	278	# Changes to submodules require special treatment. This loop writes a
	279	# temporary file to both the left and right directories to show the
	280	# change in the recorded SHA1 for the submodule.
	281	for my $path (keys %submodule) {
ceb1497a	282	my $ok;
7e0abcec	283	if (defined($submodule{$path}{left})) {
ceb1497a DA	284	$ok = write_to_file("$ldir/$path",
ceb1497a DA	285	"Subproject commit $submodule{$path}{left}");
7e0abcec TH	286	}
7e0abcec TH	287	if (defined($submodule{$path}{right})) {
ceb1497a DA	288	$ok = write_to_file("$rdir/$path",
ceb1497a DA	289	"Subproject commit $submodule{$path}{right}");
7e0abcec	290	}
ceb1497a	291	exit_cleanup($tmpdir, 1) if not $ok;
7e0abcec TH	292	}
	293
	294	# Symbolic links require special treatment. The standard "git diff"
	295	# shows only the link itself, not the contents of the link target.
	296	# This loop replicates that behavior.
	297	for my $path (keys %symlink) {
ceb1497a	298	my $ok;
7e0abcec	299	if (defined($symlink{$path}{left})) {
ceb1497a DA	300	$ok = write_to_file("$ldir/$path",
ceb1497a DA	301	$symlink{$path}{left});
7e0abcec TH	302	}
7e0abcec TH	303	if (defined($symlink{$path}{right})) {
ceb1497a DA	304	$ok = write_to_file("$rdir/$path",
ceb1497a DA	305	$symlink{$path}{right});
7e0abcec	306	}
ceb1497a	307	exit_cleanup($tmpdir, 1) if not $ok;
7e0abcec TH	308	}
7e0abcec TH	309
ceb1497a	310	return ($ldir, $rdir, $tmpdir, @working_tree);
7e0abcec TH	311	}
	312
	313	sub write_to_file
	314	{
	315	my $path = shift;
	316	my $value = shift;
	317
	318	# Make sure the path to the file exists
	319	my $dir = dirname($path);
	320	unless (-d "$dir") {
ceb1497a	321	mkpath("$dir") or return 0;
7e0abcec TH	322	}
	323
	324	# If the file already exists in that location, delete it. This
	325	# is required in the case of symbolic links.
ceb1497a	326	unlink($path);
7e0abcec	327
ceb1497a	328	open(my $fh, '>', $path) or return 0;
7e0abcec TH	329	print($fh $value);
7e0abcec TH	330	close($fh);
ceb1497a DA	331
ceb1497a DA	332	return 1;
7e0abcec TH	333	}
7e0abcec TH	334
75cd7583 DA	335	sub main
	336	{
	337	# parse command-line options. all unrecognized options and arguments
	338	# are passed through to the 'git diff' command.
c9bdd505 DA	339	my %opts = (
	340	difftool_cmd => undef,
	341	dirdiff => undef,
	342	extcmd => undef,
	343	gui => undef,
	344	help => undef,
	345	prompt => undef,
190f5475 DA	346	symlinks => $^O ne 'cygwin' &&
190f5475 DA	347	$^O ne 'MSWin32' && $^O ne 'msys',
c9bdd505 DA	348	tool_help => undef,
	349	);
	350	GetOptions('g\|gui!' => \$opts{gui},
	351	'd\|dir-diff' => \$opts{dirdiff},
	352	'h' => \$opts{help},
	353	'prompt!' => \$opts{prompt},
	354	'y' => sub { $opts{prompt} = 0; },
1f229345 DA	355	'symlinks' => \$opts{symlinks},
1f229345 DA	356	'no-symlinks' => sub { $opts{symlinks} = 0; },
c9bdd505 DA	357	't\|tool:s' => \$opts{difftool_cmd},
	358	'tool-help' => \$opts{tool_help},
	359	'x\|extcmd:s' => \$opts{extcmd});
	360
	361	if (defined($opts{help})) {
75cd7583	362	usage(0);
5c38ea31	363	}
c9bdd505	364	if (defined($opts{tool_help})) {
75cd7583	365	print_tool_help();
3f94ff75	366	}
c9bdd505 DA	367	if (defined($opts{difftool_cmd})) {
	368	if (length($opts{difftool_cmd}) > 0) {
	369	$ENV{GIT_DIFF_TOOL} = $opts{difftool_cmd};
75cd7583 DA	370	} else {
	371	print "No <tool> given for --tool=<tool>\n";
	372	usage(1);
	373	}
	374	}
c9bdd505 DA	375	if (defined($opts{extcmd})) {
	376	if (length($opts{extcmd}) > 0) {
	377	$ENV{GIT_DIFFTOOL_EXTCMD} = $opts{extcmd};
75cd7583 DA	378	} else {
	379	print "No <cmd> given for --extcmd=<cmd>\n";
	380	usage(1);
	381	}
	382	}
c9bdd505 DA	383	if ($opts{gui}) {
c9bdd505 DA	384	my $guitool = Git::config('diff.guitool');
af14b5cf	385	if (defined($guitool) && length($guitool) > 0) {
75cd7583 DA	386	$ENV{GIT_DIFF_TOOL} = $guitool;
	387	}
	388	}
	389
	390	# In directory diff mode, 'git-difftool--helper' is called once
	391	# to compare the a/b directories. In file diff mode, 'git diff'
	392	# will invoke a separate instance of 'git-difftool--helper' for
	393	# each file that changed.
c9bdd505	394	if (defined($opts{dirdiff})) {
1f229345	395	dir_diff($opts{extcmd}, $opts{symlinks});
75cd7583	396	} else {
c9bdd505	397	file_diff($opts{prompt});
3f94ff75 TH	398	}
3f94ff75 TH	399	}
7e0abcec	400
75cd7583 DA	401	sub dir_diff
75cd7583 DA	402	{
1f229345	403	my ($extcmd, $symlinks) = @_;
75cd7583	404	my $rc;
ceb1497a	405	my $error = 0;
75cd7583	406	my $repo = Git->repository();
94eaa806	407	my $workdir = find_worktree();
ceb1497a DA	408	my ($a, $b, $tmpdir, @worktree) =
	409	setup_dir_diff($repo, $workdir, $symlinks);
	410
7e0abcec TH	411	if (defined($extcmd)) {
7e0abcec TH	412	$rc = system($extcmd, $a, $b);
3f94ff75	413	} else {
7e0abcec TH	414	$ENV{GIT_DIFFTOOL_DIRDIFF} = 'true';
7e0abcec TH	415	$rc = system('git', 'difftool--helper', $a, $b);
d531174f	416	}
7e0abcec TH	417	# If the diff including working copy files and those
7e0abcec TH	418	# files were modified during the diff, then the changes
1f229345 DA	419	# should be copied back to the working tree.
	420	# Do not copy back files when symlinks are used and the
	421	# external tool did not replace the original link with a file.
67aa147a JK	422	#
	423	# These hashes are loaded lazily since they aren't needed
	424	# in the common case of --symlinks and the difftool updating
	425	# files through the symlink.
	426	my %wt_modified;
	427	my %tmp_modified;
	428	my $indices_loaded = 0;
	429
1f229345 DA	430	for my $file (@worktree) {
1f229345 DA	431	next if $symlinks && -l "$b/$file";
283abb2c DA	432	next if ! -f "$b/$file";
283abb2c DA	433
67aa147a JK	434	if (!$indices_loaded) {
	435	%wt_modified = changed_files($repo->repo_path(),
	436	"$tmpdir/wtindex", "$workdir");
	437	%tmp_modified = changed_files($repo->repo_path(),
	438	"$tmpdir/wtindex", "$b");
	439	$indices_loaded = 1;
	440	}
	441
	442	if (exists $wt_modified{$file} and exists $tmp_modified{$file}) {
	443	my $errmsg = "warning: Both files modified: ";
	444	$errmsg .= "'$workdir/$file' and '$b/$file'.\n";
	445	$errmsg .= "warning: Working tree file has been left.\n";
	446	$errmsg .= "warning:\n";
283abb2c	447	warn $errmsg;
ceb1497a	448	$error = 1;
67aa147a	449	} elsif (exists $tmp_modified{$file}) {
1f229345	450	my $mode = stat("$b/$file")->mode;
ceb1497a DA	451	copy("$b/$file", "$workdir/$file") or
	452	exit_cleanup($tmpdir, 1);
	453
	454	chmod($mode, "$workdir/$file") or
	455	exit_cleanup($tmpdir, 1);
05df5326	456	}
7e0abcec	457	}
ceb1497a DA	458	if ($error) {
	459	warn "warning: Temporary files exist in '$tmpdir'.\n";
	460	warn "warning: You may want to cleanup or recover these.\n";
	461	exit(1);
	462	} else {
	463	exit_cleanup($tmpdir, $rc);
	464	}
75cd7583 DA	465	}
	466
	467	sub file_diff
	468	{
	469	my ($prompt) = @_;
	470
7e0abcec TH	471	if (defined($prompt)) {
	472	if ($prompt) {
	473	$ENV{GIT_DIFFTOOL_PROMPT} = 'true';
	474	} else {
	475	$ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
	476	}
	477	}
	478
	479	$ENV{GIT_PAGER} = '';
	480	$ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
	481
	482	# ActiveState Perl for Win32 does not implement POSIX semantics of
	483	# exec* system call. It just spawns the given executable and finishes
	484	# the starting program, exiting with code 0.
	485	# system will at least catch the errors returned by git diff,
	486	# allowing the caller of git difftool better handling of failures.
	487	my $rc = system('git', 'diff', @ARGV);
	488	exit($rc \| ($rc >> 8));
	489	}
75cd7583 DA	490
75cd7583 DA	491	main();