#!/usr/bin/perl
use 5.008;
use strict;
use warnings;
use Getopt::Std;
use File::Temp qw(tempdir);
use Data::Dumper;
use File::Basename qw(basename dirname);
use File::Spec;
use Git;
our ($opt_h, $opt_P, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m, $opt_d, $opt_u, $opt_w, $opt_W, $opt_k);
getopts('uhPpvcfkam:d:w:W');
$opt_h && usage();
die "Need at least one commit identifier!" unless @ARGV;
# Get git-config settings
my $repo = Git->repository();
$opt_w = $repo->config('cvsexportcommit.cvsdir') unless defined $opt_w;
my $tmpdir = File::Temp::tempdir(CLEANUP => 1);
my $hash_algo = $repo->config('extensions.objectformat') || 'sha1';
my $hexsz = $hash_algo eq 'sha256' ? 64 : 40;
if ($opt_w || $opt_W) {
# Remember where GIT_DIR is before changing to CVS checkout
unless ($ENV{GIT_DIR}) {
# No GIT_DIR set. Figure it out for ourselves
my $gd =`git rev-parse --git-dir`;
chomp($gd);
$ENV{GIT_DIR} = $gd;
}
# On MSYS, convert a Windows-style path to an MSYS-style path
# so that rel2abs() below works correctly.
if ($^O eq 'msys') {
$ENV{GIT_DIR} =~ s#^([[:alpha:]]):/#/$1/#;
}
# Make sure GIT_DIR is absolute
$ENV{GIT_DIR} = File::Spec->rel2abs($ENV{GIT_DIR});
}
if ($opt_w) {
if (! -d $opt_w."/CVS" ) {
die "$opt_w is not a CVS checkout";
}
chdir $opt_w or die "Cannot change to CVS checkout at $opt_w";
}
unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
die "GIT_DIR is not defined or is unreadable";
}
my @cvs;
if ($opt_d) {
@cvs = ('cvs', '-d', $opt_d);
} else {
@cvs = ('cvs');
}
# resolve target commit
my $commit;
$commit = pop @ARGV;
$commit = safe_pipe_capture('git', 'rev-parse', '--verify', "$commit^0");
chomp $commit;
if ($?) {
die "The commit reference $commit did not resolve!";
}
# resolve what parent we want
my $parent;
if (@ARGV) {
$parent = pop @ARGV;
$parent = safe_pipe_capture('git', 'rev-parse', '--verify', "$parent^0");
chomp $parent;
if ($?) {
die "The parent reference did not resolve!";
}
}
# find parents from the commit itself
my @commit = safe_pipe_capture('git', 'cat-file', 'commit', $commit);
my @parents;
my $committer;
my $author;
my $stage = 'headers'; # headers, msg
my $title;
my $msg = '';
foreach my $line (@commit) {
chomp $line;
if ($stage eq 'headers' && $line eq '') {
$stage = 'msg';
next;
}
if ($stage eq 'headers') {
if ($line =~ m/^parent ([0-9a-f]{$hexsz})$/) { # found a parent
push @parents, $1;
} elsif ($line =~ m/^author (.+) \d+ [-+]\d+$/) {
$author = $1;
} elsif ($line =~ m/^committer (.+) \d+ [-+]\d+$/) {
$committer = $1;
}
} else {
$msg .= $line . "\n";
unless ($title) {
$title = $line;
}
}
}
my $noparent = "0" x $hexsz;
if ($parent) {
my $found;
# double check that it's a valid parent
foreach my $p (@parents) {
if ($p eq $parent) {
$found = 1;
last;
}; # found it
}
die "Did not find $parent in the parents for this commit!" if !$found and !$opt_P;
} else { # we don't have a parent from the cmdline...
if (@parents == 1) { # it's safe to get it from the commit
$parent = $parents[0];
} elsif (@parents == 0) { # there is no parent
$parent = $noparent;
} else { # cannot choose automatically from multiple parents
die "This commit has more than one parent -- please name the parent you want to use explicitly";
}
}
my $go_back_to = 0;
if ($opt_W) {
$opt_v && print "Resetting to $parent\n";
$go_back_to = `git symbolic-ref HEAD 2> /dev/null ||
git rev-parse HEAD` || die "Could not determine current branch";
system("git checkout -q $parent^0") && die "Could not check out $parent^0";
}
$opt_v && print "Applying to CVS commit $commit from parent $parent\n";
# grab the commit message
open(MSG, ">.msg") or die "Cannot open .msg for writing";
if ($opt_m) {
print MSG $opt_m;
}
print MSG $msg;
if ($opt_a) {
print MSG "\n\nAuthor: $author\n";
if ($author ne $committer) {
print MSG "Committer: $committer\n";
}
}
close MSG;
if ($parent eq $noparent) {
`git diff-tree --binary -p --root $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
} else {
`git diff-tree --binary -p $parent $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
}
## apply non-binary changes
# In pedantic mode require all lines of context to match. In normal
# mode, be compatible with diff/patch: assume 3 lines of context and
# require at least one line match, i.e. ignore at most 2 lines of
# context, like diff/patch do by default.
my $context = $opt_p ? '' : '-C1';
print "Checking if patch will apply\n";
my @stat;
open APPLY, "GIT_INDEX_FILE=$tmpdir/index git apply $context --summary --numstat<.cvsexportcommit.diff|" || die "cannot patch";
@stat=<APPLY>;
close APPLY || die "Cannot patch";
my (@bfiles,@files,@afiles,@dfiles);
chomp @stat;
foreach (@stat) {
push (@bfiles,$1) if m/^-\t-\t(.*)$/;
push (@files, $1) if m/^-\t-\t(.*)$/;
push (@files, $1) if m/^\d+\t\d+\t(.*)$/;
push (@afiles,$1) if m/^ create mode [0-7]+ (.*)$/;
push (@dfiles,$1) if m/^ delete mode [0-7]+ (.*)$/;
}
map { s/^"(.*)"$/$1/g } @bfiles,@files;
map { s/\\([0-7]{3})/sprintf('%c',oct $1)/eg } @bfiles,@files;
# check that the files are clean and up to date according to cvs
my $dirty;
my @dirs;
foreach my $p (@afiles) {
my $path = dirname $p;
while (!-d $path and ! grep { $_ eq $path } @dirs) {
unshift @dirs, $path;
$path = dirname $path;
}
}
# ... check dirs,
foreach my $d (@dirs) {
if (-e $d) {
$dirty = 1;
warn "$d exists and is not a directory!\n";
}
}
# ... query status of all files that we have a directory for and parse output of 'cvs status' to %cvsstat.
my @canstatusfiles;
foreach my $f (@files) {
my $path = dirname $f;
next if (grep { $_ eq $path } @dirs);
push @canstatusfiles, $f;
}
my %cvsstat;
if (@canstatusfiles) {
if ($opt_u) {
my @updated = xargs_safe_pipe_capture([@cvs, 'update'], @canstatusfiles);
print @updated;
}
# "cvs status" reorders the parameters, notably when there are multiple
# arguments with the same basename. So be precise here.
my %added = map { $_ => 1 } @afiles;
my %todo = map { $_ => 1 } @canstatusfiles;
while (%todo) {
my @canstatusfiles2 = ();
my %fullname = ();
foreach my $name (keys %todo) {
my $basename = basename($name);
# CVS reports files that don't exist in the current revision as
# "no file $basename" in its "status" output, so we should
# anticipate that. Totally unknown files will have a status
# "Unknown". However, if they exist in the Attic, their status
# will be "Up-to-date" (this means they were added once but have
# been removed).
$basename = "no file $basename" if $added{$basename};
$basename =~ s/^\s+//;
$basename =~ s/\s+$//;
if (!exists($fullname{$basename})) {
$fullname{$basename} = $name;
push (@canstatusfiles2, $name);
delete($todo{$name});
}
}
my @cvsoutput;
@cvsoutput = xargs_safe_pipe_capture([@cvs, 'status'], @canstatusfiles2);
foreach my $l (@cvsoutput) {
chomp $l;
next unless
my ($file, $status) = $l =~ /^File:\s+(.*\S)\s+Status: (.*)$/;
my $fullname = $fullname{$file};
print STDERR "Huh? Status '$status' reported for unexpected file '$file'\n"
unless defined $fullname;
# This response means the file does not exist except in
# CVS's attic, so set the status accordingly
$status = "In-attic"
if $file =~ /^no file /
&& $status eq 'Up-to-date';
$cvsstat{$fullname{$file}} = $status
if defined $fullname{$file};
}
}
}
# ... Validate that new files have the correct status
foreach my $f (@afiles) {
next unless defined(my $stat = $cvsstat{$f});
# This means the file has never been seen before
next if $stat eq 'Unknown';
# This means the file has been seen before but was removed
next if $stat eq 'In-attic';
$dirty = 1;
warn "File $f is already known in your CVS checkout -- perhaps it has been added by another user. Or this may indicate that it exists on a different branch. If this is the case, use -f to force the merge.\n";
warn "Status was: $cvsstat{$f}\n";
}
# ... validate known files.
foreach my $f (@files) {
next if grep { $_ eq $f } @afiles;
# TODO:we need to handle removed in cvs
unless (defined ($cvsstat{$f}) and $cvsstat{$f} eq "Up-to-date") {
$dirty = 1;
warn "File $f not up to date but has status '$cvsstat{$f}' in your CVS checkout!\n";
}
# Depending on how your GIT tree got imported from CVS you may
# have a conflict between expanded keywords in your CVS tree and
# unexpanded keywords in the patch about to be applied.
if ($opt_k) {
my $orig_file ="$f.orig";
rename $f, $orig_file;
open(FILTER_IN, "<$orig_file") or die "Cannot open $orig_file\n";
open(FILTER_OUT, ">$f") or die "Cannot open $f\n";
while (<FILTER_IN>)
{
my $line = $_;
$line =~ s/\$([A-Z][a-z]+):[^\$]+\$/\$$1\$/g;
print FILTER_OUT $line;
}
close FILTER_IN;
close FILTER_OUT;
}
}
if ($dirty) {
if ($opt_f) { warn "The tree is not clean -- forced merge\n";
$dirty = 0;
} else {
die "Exiting: your CVS tree is not clean for this merge.";
}
}
print "Applying\n";
if ($opt_W) {
system("git checkout -q $commit^0") && die "cannot patch";
} else {
`GIT_INDEX_FILE=$tmpdir/index git apply $context --summary --numstat --apply <.cvsexportcommit.diff` || die "cannot patch";
}
print "Patch applied successfully. Adding new files and directories to CVS\n";
my $dirtypatch = 0;
#
# We have to add the directories in order otherwise we will have
# problems when we try and add the sub-directory of a directory we
# have not added yet.
#
# Luckily this is easy to deal with by sorting the directories and
# dealing with the shortest ones first.
#
@dirs = sort { length $a <=> length $b} @dirs;
foreach my $d (@dirs) {
if (system(@cvs,'add',$d)) {
$dirtypatch = 1;
warn "Failed to cvs add directory $d -- you may need to do it manually";
}
}
foreach my $f (@afiles) {
if (grep { $_ eq $f } @bfiles) {
system(@cvs, 'add','-kb',$f);
} else {
system(@cvs, 'add', $f);
}
if ($?) {
$dirtypatch = 1;
warn "Failed to cvs add $f -- you may need to do it manually";
}
}
foreach my $f (@dfiles) {
system(@cvs, 'rm', '-f', $f);
if ($?) {
$dirtypatch = 1;
warn "Failed to cvs rm -f $f -- you may need to do it manually";
}
}
print "Commit to CVS\n";
print "Patch title (first comment line): $title\n";
my @commitfiles = map { unless (m/\s/) { '\''.$_.'\''; } else { $_; }; } (@files);
my $cmd = join(' ', @cvs)." commit -F .msg @commitfiles";
if ($dirtypatch) {
print "NOTE: One or more hunks failed to apply cleanly.\n";
print "You'll need to apply the patch in .cvsexportcommit.diff manually\n";
print "using a patch program. After applying the patch and resolving the\n";
print "problems you may commit using:";
print "\n cd \"$opt_w\"" if $opt_w;
print "\n $cmd\n";
print "\n git checkout $go_back_to\n" if $go_back_to;
print "\n";
exit(1);
}
if ($opt_c) {
print "Autocommit\n $cmd\n";
print xargs_safe_pipe_capture([@cvs, 'commit', '-F', '.msg'], @files);
if ($?) {
die "Exiting: The commit did not succeed";
}
print "Committed successfully to CVS\n";
# clean up
unlink(".msg");
} else {
print "Ready for you to commit, just run:\n\n $cmd\n";
}
# clean up
unlink(".cvsexportcommit.diff");
if ($opt_W) {
system("git checkout $go_back_to") && die "cannot move back to $go_back_to";
if (!($go_back_to =~ /^[0-9a-fA-F]{$hexsz}$/)) {
system("git symbolic-ref HEAD $go_back_to") &&
die "cannot move back to $go_back_to";
}
}
# CVS version 1.11.x and 1.12.x sleeps the wrong way to ensure the timestamp
# used by CVS and the one set by subsequence file modifications are different.
# If they are not different CVS will not detect changes.
sleep(1);
sub usage {
print STDERR <<END;
usage: GIT_DIR=/path/to/.git git cvsexportcommit [-h] [-p] [-v] [-c] [-f] [-u] [-k] [-w cvsworkdir] [-m msgprefix] [ parent ] commit
END
exit(1);
}
# An alternative to `command` that allows input to be passed as an array
# to work around shell problems with weird characters in arguments
# if the exec returns non-zero we die
sub safe_pipe_capture {
my @output;
if (my $pid = open my $child, '-|') {
binmode($child, ":crlf");
@output = (<$child>);
close $child or die join(' ',@_).": $! $?";
} else {
exec(@_) or die "$! $?"; # exec() can fail the executable can't be found
}
return wantarray ? @output : join('',@output);
}
sub xargs_safe_pipe_capture {
my $MAX_ARG_LENGTH = 65536;
my $cmd = shift;
my @output;
my $output;
while(@_) {
my @args;
my $length = 0;
while(@_ && $length < $MAX_ARG_LENGTH) {
push @args, shift;
$length += length($args[$#args]);
}
if (wantarray) {
push @output, safe_pipe_capture(@$cmd, @args);
}
else {
$output .= safe_pipe_capture(@$cmd, @args);
}
}
return wantarray ? @output : $output;
}
