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Diffstat (limited to 'git-difftool.perl')
| -rwxr-xr-x | git-difftool.perl | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/git-difftool.perl b/git-difftool.perl new file mode 100755 index 0000000000..ae1e0525d8 --- /dev/null +++ b/git-difftool.perl @@ -0,0 +1,361 @@ +#!/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 File::Basename qw(dirname); +use File::Copy; +use File::Find; +use File::stat; +use File::Path qw(mkpath); +use File::Temp qw(tempdir); +use Getopt::Long qw(:config pass_through); +use Git; + +my @tools; +my @working_tree; +my $rc; +my $repo = Git->repository(); +my $repo_path = $repo->repo_path(); + +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. + my $worktree; + my $env_worktree = $ENV{GIT_WORK_TREE}; + my $core_worktree = Git::config('core.worktree'); + + if (defined($env_worktree) and (length($env_worktree) > 0)) { + $worktree = $env_worktree; + } elsif (defined($core_worktree) and (length($core_worktree) > 0)) { + $worktree = $core_worktree; + } else { + $worktree = $repo->wc_path(); + } + + return $worktree; +} + +my $workdir = find_worktree(); + +sub filter_tool_scripts +{ + if (-d $_) { + if ($_ ne ".") { + # Ignore files in subdirectories + $File::Find::prune = 1; + } + } else { + if ((-f $_) && ($_ ne "defaults")) { + push(@tools, $_); + } + } +} + +sub print_tool_help +{ + my ($cmd, @found, @notfound); + my $gitpath = Git::exec_path(); + + find(\&filter_tool_scripts, "$gitpath/mergetools"); + + foreach my $tool (@tools) { + $cmd = "TOOL_MODE=diff"; + $cmd .= ' && . "$(git --exec-path)/git-mergetool--lib"'; + $cmd .= " && get_merge_tool_path $tool >/dev/null 2>&1"; + $cmd .= " && can_diff >/dev/null 2>&1"; + if (system('sh', '-c', $cmd) == 0) { + push(@found, $tool); + } else { + push(@notfound, $tool); + } + } + + print "'git difftool --tool=<tool>' may be set to one of the following:\n"; + print "\t$_\n" for (sort(@found)); + + print "\nThe following tools are valid, but not currently available:\n"; + print "\t$_\n" for (sort(@notfound)); + + print "\nNOTE: Some of the tools listed above only work in a windowed\n"; + print "environment. If run in a terminal-only session, they will fail.\n"; + + exit(0); +} + +sub setup_dir_diff +{ + # 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 $diffrepo = Git->repository(Repository => $repo_path, WorkingCopy => $workdir); + my $diffrtn = $diffrepo->command_oneline('diff', '--raw', '--no-abbrev', '-z', @ARGV); + exit(0) if (length($diffrtn) == 0); + + # Setup temp directories + my $tmpdir = tempdir('git-diffall.XXXXX', CLEANUP => 1, TMPDIR => 1); + my $ldir = "$tmpdir/left"; + my $rdir = "$tmpdir/right"; + mkpath($ldir) or die $!; + mkpath($rdir) or die $!; + + # 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 %submodule; + my %symlink; + my @rawdiff = split('\0', $diffrtn); + + my $i = 0; + while ($i < $#rawdiff) { + if ($rawdiff[$i] =~ /^::/) { + print "Combined diff formats ('-c' and '--cc') are not supported in directory diff mode.\n"; + exit(1); + } + + my ($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 $null_mode) { + if ($rsha1 ne $null_sha1) { + $rindex .= "$rmode $rsha1\t$dst_path\0"; + } else { + push(@working_tree, $dst_path); + } + } + } + + # 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); + $rc = system('git', 'checkout-index', '--all', "--prefix=$ldir/"); + exit($rc | ($rc >> 8)) 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($rc | ($rc >> 8)) if ($rc != 0); + + # 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 + for my $file (@working_tree) { + my $dir = dirname($file); + unless (-d "$rdir/$dir") { + mkpath("$rdir/$dir") or die $!; + } + copy("$workdir/$file", "$rdir/$file") or die $!; + chmod(stat("$workdir/$file")->mode, "$rdir/$file") or die $!; + } + + # 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 $path (keys %submodule) { + if (defined($submodule{$path}{left})) { + write_to_file("$ldir/$path", "Subproject commit $submodule{$path}{left}"); + } + if (defined($submodule{$path}{right})) { + write_to_file("$rdir/$path", "Subproject commit $submodule{$path}{right}"); + } + } + + # 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 $path (keys %symlink) { + if (defined($symlink{$path}{left})) { + write_to_file("$ldir/$path", $symlink{$path}{left}); + } + if (defined($symlink{$path}{right})) { + write_to_file("$rdir/$path", $symlink{$path}{right}); + } + } + + return ($ldir, $rdir); +} + +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 die $!; + } + + # If the file already exists in that location, delete it. This + # is required in the case of symbolic links. + unlink("$path"); + + open(my $fh, '>', "$path") or die $!; + print($fh $value); + close($fh); +} + +# parse command-line options. all unrecognized options and arguments +# are passed through to the 'git diff' command. +my ($difftool_cmd, $dirdiff, $extcmd, $gui, $help, $prompt, $tool_help); +GetOptions('g|gui!' => \$gui, + 'd|dir-diff' => \$dirdiff, + 'h' => \$help, + 'prompt!' => \$prompt, + 'y' => sub { $prompt = 0; }, + 't|tool:s' => \$difftool_cmd, + 'tool-help' => \$tool_help, + 'x|extcmd:s' => \$extcmd); + +if (defined($help)) { + usage(0); +} +if (defined($tool_help)) { + print_tool_help(); +} +if (defined($difftool_cmd)) { + if (length($difftool_cmd) > 0) { + $ENV{GIT_DIFF_TOOL} = $difftool_cmd; + } else { + print "No <tool> given for --tool=<tool>\n"; + usage(1); + } +} +if (defined($extcmd)) { + if (length($extcmd) > 0) { + $ENV{GIT_DIFFTOOL_EXTCMD} = $extcmd; + } else { + print "No <cmd> given for --extcmd=<cmd>\n"; + usage(1); + } +} +if ($gui) { + my $guitool = ''; + $guitool = Git::config('diff.guitool'); + if (length($guitool) > 0) { + $ENV{GIT_DIFF_TOOL} = $guitool; + } +} + +# In directory diff mode, 'git-difftool--helper' is called once +# to compare the a/b directories. In file diff mode, 'git diff' +# will invoke a separate instance of 'git-difftool--helper' for +# each file that changed. +if (defined($dirdiff)) { + my ($a, $b) = setup_dir_diff(); + if (defined($extcmd)) { + $rc = system($extcmd, $a, $b); + } else { + $ENV{GIT_DIFFTOOL_DIRDIFF} = 'true'; + $rc = system('git', 'difftool--helper', $a, $b); + } + + exit($rc | ($rc >> 8)) if ($rc != 0); + + # 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 + for my $file (@working_tree) { + copy("$b/$file", "$workdir/$file") or die $!; + chmod(stat("$b/$file")->mode, "$workdir/$file") or die $!; + } +} else { + if (defined($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)); +} |