aboutsummaryrefslogtreecommitdiff
path: root/git-cvsexportcommit.perl
blob: b6036bd4d305215b4a70b6fd0fe54d7607dbe068 (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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
#!/usr/bin/perl -w

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

our ($opt_h, $opt_P, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m, $opt_d, $opt_u, $opt_w);

getopts('uhPpvcfam:d:w:');

$opt_h && usage();

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

if ($opt_w) {
	# Remember where GIT_DIR is before changing to CVS checkout
	unless ($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;
	}
	# Make sure GIT_DIR is absolute
	$ENV{GIT_DIR} = File::Spec->rel2abs($ENV{GIT_DIR});

	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 (\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;
	}
    }
}

my $noparent = "0000000000000000000000000000000000000000";
if ($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";
    }
}

$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_DIR= 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);

	$basename = "no file " . $basename if (exists($added{$basename}));
	chomp($basename);

	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 $l;
        if ($l =~ /^File:\s+(.*\S)\s+Status: (.*)$/) {
	  if (!exists($fullname{$1})) {
	    print STDERR "Huh? Status reported for unexpected file '$1'\n";
	  } else {
	    $cvsstat{$fullname{$1}} = $2;
	  }
	}
      }
    }
}

# ... validate new files,
foreach my $f (@afiles) {
    if (defined ($cvsstat{$f}) and $cvsstat{$f} ne "Unknown") {
	$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{$f}' in your CVS checkout!\n";
    }
}
if ($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";
`GIT_DIR= 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\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");

# 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 ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-u] [-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 $child, '-|') {
	@output = (<$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;
}