[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_m );

getopts('hpvcfm:');

$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);

print Dumper(@ARGV);
# 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;
foreach my $p (@commit) {
    if ($p =~ m/^$/) { # end of commit headers, we're done
	last;
    }
    if ($p =~ m/^parent (\w{40})$/) { # found a parent
	push @parents, $1;
    }
}

if ($parent) {
    # double check that it's a valid parent
    foreach my $p (@parents) {
	my $found;
	if ($p eq $parent) {
	    $found = 1;
	    last;
	}; # found it
	die "Did not find $parent in the parents for this commit!";
    }
} 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";
print MSG $opt_m;
close MSG;

`git-cat-file commit $commit | sed -e '1,/^\$/d' >> .msg`;
$? && die "Error extracting the commit message";

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