summaryrefslogtreecommitdiff
path: root/git-cvsexportcommit.perl
blob: 7074b0c21b14b0ff358b7ddc9f2b0076fb7ffca4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
#!/usr/bin/perl -w

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

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 );

getopt('hpvc');

$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;
$commit = `git-rev-parse --verify "$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;
    $parent =  `git-rev-parse --verify "$parent"^0"`;
    chomp $parent;
    if ($?) {
	die "The parent reference did not resolve!";
    }
}

# find parents from the commit itself
my @commit  = `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!";
s    }
} 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
`git-cat-file commit $commit | sed -e '1,/^\$/d' > .msg`;
$? && die "Error extraction the commit message";

my (@afiles, @dfiles, @mfiles);
my @files = `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') {
	push @afiles, $fields[5];
    }
    if ($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 $f (@afiles, @mfiles, @dfiles) {
    # TODO:we need to handle removed in cvs and/or new (from git) 
    my $status = `cvs -q status "$f" | grep '^File: '`;

    unless ($status =~ m/Status: Up-to-date$/) {
	$dirty = 1;
	warn "File $f not up to date in your CVS checkout!\n";
    }
}
if ($dirty) {
    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 "'Patching' binary files\n";

my @bfiles = `git-diff-tree -p $parent $commit | grep '^Binary'`;
@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 = `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`;
    `cmp -q $f $tmpdir/blob`;
    if ($?) {
	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) {
    `cvs add $f`;
    if ($?) {
	$dirty = 1;
	warn "Failed to cvs add $f -- you may need to do it manually";
    }
}

foreach my $f (@dfiles) {
    `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;
}


if ($opt_c) {
    print "Autocommit\n  $cmd\n";
    print `cvs commit -F .msg $commitfiles 2>&1`;
    if ($?) {
	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/.gi ${\basename $0}      # fetch/update GIT from CVS
       [-h] [-p] [ parent ] commit
END
	exit(1);
}

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