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

#!/usr/bin/perl -w

# Known limitations:
# - cannot add or remove binary files
# - does not propagate permissions
# - tells "ready for commit" even when things could not be completed
#   (eg addition of a binary file)

use strict;
use Getopt::Std;
use File::Temp qw(tempdir);
use Data::Dumper;
use File::Basename qw(basename dirname);

unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
    die "GIT_DIR is not defined or is unreadable";
}

our ($opt_h, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m );

getopts('hpvcfam:');

$opt_h && usage();

die "Need at least one commit identifier!" unless @ARGV;

# setup a tempdir
our ($tmpdir, $tmpdirname) = tempdir('git-cvsapplycommit-XXXXXX',
				     TMPDIR => 1,
				     CLEANUP => 1);

# 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 (\w{40})$/) { # 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;
	}
    }
}

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;
} 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];
    } else { # or perhaps not!
	die "This commit has more than one parent -- please name the parent you want to use explicitly";
    }
}

$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;

my (@afiles, @dfiles, @mfiles, @dirs);
my @files = safe_pipe_capture('git-diff-tree', '-r', $parent, $commit);
#print @files;
$? && die "Error in git-diff-tree";
foreach my $f (@files) {
    chomp $f;
    my @fields = split(m!\s+!, $f);
    if ($fields[4] eq 'A') {
        my $path = $fields[5];
	push @afiles, $path;
        # add any needed parent directories
	$path = dirname $path;
	while (!-d $path and ! grep { $_ eq $path } @dirs) {
	    unshift @dirs, $path;
	    $path = dirname $path;
	}
    }
    if ($fields[4] eq 'M') {
	push @mfiles, $fields[5];
    }
    if ($fields[4] eq 'R') {
	push @dfiles, $fields[5];
    }
}
$opt_v && print "The commit affects:\n ";
$opt_v && print join ("\n ", @afiles,@mfiles,@dfiles) . "\n\n";
undef @files; # don't need it anymore

# check that the files are clean and up to date according to cvs
my $dirty;
foreach my $d (@dirs) {
    if (-e $d) {
	$dirty = 1;
	warn "$d exists and is not a directory!\n";
    }
}
foreach my $f (@afiles) {
    # This should return only one value
    my @status = grep(m/^File/,  safe_pipe_capture('cvs', '-q', 'status' ,$f));
    if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
    if (-d dirname $f and $status[0] !~ m/Status: Unknown$/
	and $status[0] !~ m/^File: no file /) {
 	$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: $status[0]\n";
    }
}
foreach my $f (@mfiles, @dfiles) {
    # TODO:we need to handle removed in cvs
    my @status = grep(m/^File/,  safe_pipe_capture('cvs', '-q', 'status' ,$f));
    if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
    unless ($status[0] =~ m/Status: Up-to-date$/) {
	$dirty = 1;
	warn "File $f not up to date in your CVS checkout!\n";
    }
}
if ($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.";
    }
}

###
### NOTE: if you are planning to die() past this point
###       you MUST call cleanupcvs(@files) before die()
###


print "Creating new directories\n";
foreach my $d (@dirs) {
    unless (mkdir $d) {
        warn "Could not mkdir $d: $!";
	$dirty = 1;
    }
    `cvs add $d`;
    if ($?) {
	$dirty = 1;
	warn "Failed to cvs add directory $d -- you may need to do it manually";
    }
}

print "'Patching' binary files\n";

my @bfiles = grep(m/^Binary/, safe_pipe_capture('git-diff-tree', '-p', $parent, $commit));
@bfiles = map { chomp } @bfiles;
foreach my $f (@bfiles) {
    # check that the file in cvs matches the "old" file
    # extract the file to $tmpdir and compare with cmp
    my $tree = safe_pipe_capture('git-rev-parse', "$parent^{tree}");
    chomp $tree;
    my $blob = `git-ls-tree $tree "$f" | cut -f 1 | cut -d ' ' -f 3`;
    chomp $blob;
    `git-cat-file blob $blob > $tmpdir/blob`;
    if (system('cmp', '-s', $f, "$tmpdir/blob")) {
	warn "Binary file $f in CVS does not match parent.\n";
	$dirty = 1;
	next;
    }

    # replace with the new file
     `git-cat-file blob $blob > $f`;

    # TODO: something smart with file modes

}
if ($dirty) {
    cleanupcvs(@files);
    die "Exiting: Binary files in CVS do not match parent";
}

## apply non-binary changes
my $fuzz = $opt_p ? 0 : 2;

print "Patching non-binary files\n";
print `(git-diff-tree -p $parent -p $commit | patch -p1 -F $fuzz ) 2>&1`;

my $dirtypatch = 0;
if (($? >> 8) == 2) {
    cleanupcvs(@files);
    die "Exiting: Patch reported serious trouble -- you will have to apply this patch manually";
} elsif (($? >> 8) == 1) { # some hunks failed to apply
    $dirtypatch = 1;
}

foreach my $f (@afiles) {
    system('cvs', 'add', $f);
    if ($?) {
	$dirty = 1;
	warn "Failed to cvs add $f -- you may need to do it manually";
    }
}

foreach my $f (@dfiles) {
    system('cvs', 'rm', '-f', $f);
    if ($?) {
	$dirty = 1;
	warn "Failed to cvs rm -f $f -- you may need to do it manually";
    }
}

print "Commit to CVS\n";
print "Patch: $title\n";
my $commitfiles = join(' ', @afiles, @mfiles, @dfiles);
my $cmd = "cvs commit -F .msg $commitfiles";

if ($dirtypatch) {
    print "NOTE: One or more hunks failed to apply cleanly.\n";
    print "Resolve the conflicts and then commit using:\n";
    print "\n    $cmd\n\n";
    exit(1);
}


if ($opt_c) {
    print "Autocommit\n  $cmd\n";
    print safe_pipe_capture('cvs', 'commit', '-F', '.msg', @afiles, @mfiles, @dfiles);
    if ($?) {
	cleanupcvs(@files);
	die "Exiting: The commit did not succeed";
    }
    print "Committed successfully to CVS\n";
} else {
    print "Ready for you to commit, just run:\n\n   $cmd\n";
}
sub usage {
	print STDERR <<END;
Usage: GIT_DIR=/path/to/.git ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-m msgprefix] [ parent ] commit
END
	exit(1);
}

# ensure cvs is clean before we die
sub cleanupcvs {
    my @files = @_;
    foreach my $f (@files) {
	system('cvs', '-q', 'update', '-C', $f);
	if ($?) {
	    warn "Warning! Failed to cleanup state of $f\n";
	}
    }
}

# 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 $child, '-|') {
	@output = (<$child>);
	close $child or die join(' ',@_).": $! $?";
    } else {
	exec(@_) or die "$! $?"; # exec() can fail the executable can't be found
    }
    return wantarray ? @output : join('',@output);
}
Commit	Line	Data
5e0306ad ML	1	#!/usr/bin/perl -w
5e0306ad ML	2
0d71b31a YD	3	# Known limitations:
0d71b31a YD	4	# - cannot add or remove binary files
0d71b31a YD	5	# - does not propagate permissions
	6	# - tells "ready for commit" even when things could not be completed
	7	# (eg addition of a binary file)
	8
5e0306ad ML	9	use strict;
	10	use Getopt::Std;
	11	use File::Temp qw(tempdir);
	12	use Data::Dumper;
3f0f756b	13	use File::Basename qw(basename dirname);
5e0306ad ML	14
	15	unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
	16	die "GIT_DIR is not defined or is unreadable";
	17	}
	18
1b91abe3	19	our ($opt_h, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m );
5e0306ad	20
1b91abe3	21	getopts('hpvcfam:');
5e0306ad ML	22
	23	$opt_h && usage();
	24
	25	die "Need at least one commit identifier!" unless @ARGV;
	26
	27	# setup a tempdir
	28	our ($tmpdir, $tmpdirname) = tempdir('git-cvsapplycommit-XXXXXX',
	29	TMPDIR => 1,
	30	CLEANUP => 1);
	31
5e0306ad ML	32	# resolve target commit
	33	my $commit;
	34	$commit = pop @ARGV;
d41df15e	35	$commit = safe_pipe_capture('git-rev-parse', '--verify', "$commit^0");
5e0306ad ML	36	chomp $commit;
	37	if ($?) {
	38	die "The commit reference $commit did not resolve!";
	39	}
	40
	41	# resolve what parent we want
	42	my $parent;
	43	if (@ARGV) {
	44	$parent = pop @ARGV;
d41df15e	45	$parent = safe_pipe_capture('git-rev-parse', '--verify', "$parent^0");
5e0306ad ML	46	chomp $parent;
	47	if ($?) {
	48	die "The parent reference did not resolve!";
	49	}
	50	}
	51
	52	# find parents from the commit itself
d41df15e	53	my @commit = safe_pipe_capture('git-cat-file', 'commit', $commit);
5e0306ad	54	my @parents;
1b91abe3 ML	55	my $committer;
	56	my $author;
	57	my $stage = 'headers'; # headers, msg
	58	my $title;
	59	my $msg = '';
	60
	61	foreach my $line (@commit) {
	62	chomp $line;
	63	if ($stage eq 'headers' && $line eq '') {
	64	$stage = 'msg';
	65	next;
5e0306ad	66	}
1b91abe3 ML	67
	68	if ($stage eq 'headers') {
	69	if ($line =~ m/^parent (\w{40})$/) { # found a parent
	70	push @parents, $1;
	71	} elsif ($line =~ m/^author (.+) \d+ \+\d+$/) {
	72	$author = $1;
	73	} elsif ($line =~ m/^committer (.+) \d+ \+\d+$/) {
	74	$committer = $1;
	75	}
	76	} else {
	77	$msg .= $line . "\n";
	78	unless ($title) {
	79	$title = $line;
	80	}
5e0306ad ML	81	}
	82	}
	83
	84	if ($parent) {
135a522e	85	my $found;
5e0306ad ML	86	# double check that it's a valid parent
5e0306ad ML	87	foreach my $p (@parents) {
5e0306ad ML	88	if ($p eq $parent) {
	89	$found = 1;
	90	last;
	91	}; # found it
e09f5d7b	92	}
135a522e	93	die "Did not find $parent in the parents for this commit!" if !$found;
5e0306ad ML	94	} else { # we don't have a parent from the cmdline...
	95	if (@parents == 1) { # it's safe to get it from the commit
	96	$parent = $parents[0];
	97	} else { # or perhaps not!
	98	die "This commit has more than one parent -- please name the parent you want to use explicitly";
	99	}
	100	}
	101
	102	$opt_v && print "Applying to CVS commit $commit from parent $parent\n";
	103
	104	# grab the commit message
992793c8	105	open(MSG, ">.msg") or die "Cannot open .msg for writing";
1b91abe3 ML	106	if ($opt_m) {
	107	print MSG $opt_m;
	108	}
	109	print MSG $msg;
	110	if ($opt_a) {
	111	print MSG "\n\nAuthor: $author\n";
	112	if ($author ne $committer) {
	113	print MSG "Committer: $committer\n";
	114	}
	115	}
992793c8 ML	116	close MSG;
992793c8 ML	117
3f0f756b	118	my (@afiles, @dfiles, @mfiles, @dirs);
d41df15e	119	my @files = safe_pipe_capture('git-diff-tree', '-r', $parent, $commit);
992793c8	120	#print @files;
5e0306ad ML	121	$? && die "Error in git-diff-tree";
	122	foreach my $f (@files) {
	123	chomp $f;
d41df15e	124	my @fields = split(m!\s+!, $f);
5e0306ad	125	if ($fields[4] eq 'A') {
3f0f756b YD	126	my $path = $fields[5];
	127	push @afiles, $path;
	128	# add any needed parent directories
	129	$path = dirname $path;
	130	while (!-d $path and ! grep { $_ eq $path } @dirs) {
	131	unshift @dirs, $path;
	132	$path = dirname $path;
	133	}
5e0306ad ML	134	}
	135	if ($fields[4] eq 'M') {
	136	push @mfiles, $fields[5];
	137	}
	138	if ($fields[4] eq 'R') {
	139	push @dfiles, $fields[5];
	140	}
	141	}
	142	$opt_v && print "The commit affects:\n ";
	143	$opt_v && print join ("\n ", @afiles,@mfiles,@dfiles) . "\n\n";
	144	undef @files; # don't need it anymore
	145
	146	# check that the files are clean and up to date according to cvs
	147	my $dirty;
3f0f756b YD	148	foreach my $d (@dirs) {
	149	if (-e $d) {
	150	$dirty = 1;
	151	warn "$d exists and is not a directory!\n";
	152	}
	153	}
576cfc86	154	foreach my $f (@afiles) {
d41df15e ML	155	# This should return only one value
	156	my @status = grep(m/^File/, safe_pipe_capture('cvs', '-q', 'status' ,$f));
	157	if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
3f0f756b YD	158	if (-d dirname $f and $status[0] !~ m/Status: Unknown$/
3f0f756b YD	159	and $status[0] !~ m/^File: no file /) {
d41df15e	160	$dirty = 1;
992793c8	161	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";
e9687515	162	warn "Status was: $status[0]\n";
576cfc86 YD	163	}
	164	}
	165	foreach my $f (@mfiles, @dfiles) {
	166	# TODO:we need to handle removed in cvs
d41df15e ML	167	my @status = grep(m/^File/, safe_pipe_capture('cvs', '-q', 'status' ,$f));
	168	if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
	169	unless ($status[0] =~ m/Status: Up-to-date$/) {
5e0306ad ML	170	$dirty = 1;
	171	warn "File $f not up to date in your CVS checkout!\n";
	172	}
	173	}
	174	if ($dirty) {
992793c8 ML	175	if ($opt_f) { warn "The tree is not clean -- forced merge\n";
	176	$dirty = 0;
	177	} else {
	178	die "Exiting: your CVS tree is not clean for this merge.";
	179	}
5e0306ad ML	180	}
	181
	182	###
	183	### NOTE: if you are planning to die() past this point
	184	### you MUST call cleanupcvs(@files) before die()
	185	###
	186
	187
3f0f756b YD	188	print "Creating new directories\n";
	189	foreach my $d (@dirs) {
	190	unless (mkdir $d) {
	191	warn "Could not mkdir $d: $!";
	192	$dirty = 1;
	193	}
	194	`cvs add $d`;
	195	if ($?) {
	196	$dirty = 1;
	197	warn "Failed to cvs add directory $d -- you may need to do it manually";
	198	}
	199	}
	200
5e0306ad ML	201	print "'Patching' binary files\n";
5e0306ad ML	202
d41df15e	203	my @bfiles = grep(m/^Binary/, safe_pipe_capture('git-diff-tree', '-p', $parent, $commit));
5e0306ad ML	204	@bfiles = map { chomp } @bfiles;
	205	foreach my $f (@bfiles) {
	206	# check that the file in cvs matches the "old" file
82e5a82f	207	# extract the file to $tmpdir and compare with cmp
d41df15e	208	my $tree = safe_pipe_capture('git-rev-parse', "$parent^{tree}");
5e0306ad ML	209	chomp $tree;
	210	my $blob = `git-ls-tree $tree "$f" \| cut -f 1 \| cut -d ' ' -f 3`;
	211	chomp $blob;
	212	`git-cat-file blob $blob > $tmpdir/blob`;
ff4a9ceb	213	if (system('cmp', '-s', $f, "$tmpdir/blob")) {
5e0306ad ML	214	warn "Binary file $f in CVS does not match parent.\n";
	215	$dirty = 1;
	216	next;
	217	}
	218
	219	# replace with the new file
	220	`git-cat-file blob $blob > $f`;
	221
	222	# TODO: something smart with file modes
	223
	224	}
	225	if ($dirty) {
	226	cleanupcvs(@files);
	227	die "Exiting: Binary files in CVS do not match parent";
	228	}
	229
	230	## apply non-binary changes
	231	my $fuzz = $opt_p ? 0 : 2;
	232
	233	print "Patching non-binary files\n";
	234	print `(git-diff-tree -p $parent -p $commit \| patch -p1 -F $fuzz ) 2>&1`;
	235
	236	my $dirtypatch = 0;
	237	if (($? >> 8) == 2) {
	238	cleanupcvs(@files);
	239	die "Exiting: Patch reported serious trouble -- you will have to apply this patch manually";
	240	} elsif (($? >> 8) == 1) { # some hunks failed to apply
	241	$dirtypatch = 1;
	242	}
	243
	244	foreach my $f (@afiles) {
d41df15e	245	system('cvs', 'add', $f);
5e0306ad ML	246	if ($?) {
	247	$dirty = 1;
	248	warn "Failed to cvs add $f -- you may need to do it manually";
	249	}
	250	}
	251
	252	foreach my $f (@dfiles) {
d41df15e	253	system('cvs', 'rm', '-f', $f);
5e0306ad ML	254	if ($?) {
	255	$dirty = 1;
	256	warn "Failed to cvs rm -f $f -- you may need to do it manually";
	257	}
	258	}
	259
	260	print "Commit to CVS\n";
1b91abe3	261	print "Patch: $title\n";
5e0306ad ML	262	my $commitfiles = join(' ', @afiles, @mfiles, @dfiles);
	263	my $cmd = "cvs commit -F .msg $commitfiles";
	264
	265	if ($dirtypatch) {
	266	print "NOTE: One or more hunks failed to apply cleanly.\n";
27dedf0c	267	print "Resolve the conflicts and then commit using:\n";
5e0306ad	268	print "\n $cmd\n\n";
27dedf0c	269	exit(1);
5e0306ad ML	270	}
	271
	272
	273	if ($opt_c) {
	274	print "Autocommit\n $cmd\n";
d41df15e	275	print safe_pipe_capture('cvs', 'commit', '-F', '.msg', @afiles, @mfiles, @dfiles);
5e0306ad ML	276	if ($?) {
	277	cleanupcvs(@files);
	278	die "Exiting: The commit did not succeed";
	279	}
	280	print "Committed successfully to CVS\n";
	281	} else {
	282	print "Ready for you to commit, just run:\n\n $cmd\n";
	283	}
	284	sub usage {
	285	print STDERR <<END;
992793c8	286	Usage: GIT_DIR=/path/to/.git ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-m msgprefix] [ parent ] commit
5e0306ad ML	287	END
	288	exit(1);
	289	}
	290
	291	# ensure cvs is clean before we die
	292	sub cleanupcvs {
	293	my @files = @_;
	294	foreach my $f (@files) {
d41df15e	295	system('cvs', '-q', 'update', '-C', $f);
5e0306ad ML	296	if ($?) {
	297	warn "Warning! Failed to cleanup state of $f\n";
	298	}
	299	}
	300	}
	301
82e5a82f	302	# An alternative to `command` that allows input to be passed as an array
d41df15e ML	303	# to work around shell problems with weird characters in arguments
	304	# if the exec returns non-zero we die
	305	sub safe_pipe_capture {
	306	my @output;
	307	if (my $pid = open my $child, '-\|') {
	308	@output = (<$child>);
	309	close $child or die join(' ',@_).": $! $?";
	310	} else {
	311	exec(@_) or die "$! $?"; # exec() can fail the executable can't be found
	312	}
	313	return wantarray ? @output : join('',@output);
	314	}