Andrew's git / gitweb.git / git-cvsexportcommit.perl
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git-cvsexportcommit.perlon commit git-svn: correctly handle packed-refs in refs/remotes/ (c53d696)
   1#!/usr/bin/perl -w
   2
   3# Known limitations:
   4# - does not propagate permissions
   5# - tells "ready for commit" even when things could not be completed
   6#   (not sure this is true anymore, more testing is needed)
   7# - does not handle whitespace in pathnames at all.
   8
   9use strict;
  10use Getopt::Std;
  11use File::Temp qw(tempdir);
  12use Data::Dumper;
  13use File::Basename qw(basename dirname);
  14
  15unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
  16    die "GIT_DIR is not defined or is unreadable";
  17}
  18
  19our ($opt_h, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m );
  20
  21getopts('hpvcfam:');
  22
  23$opt_h && usage();
  24
  25die "Need at least one commit identifier!" unless @ARGV;
  26
  27# setup a tempdir
  28our ($tmpdir, $tmpdirname) = tempdir('git-cvsapplycommit-XXXXXX',
  29                                     TMPDIR => 1,
  30                                     CLEANUP => 1);
  31
  32# resolve target commit
  33my $commit;
  34$commit = pop @ARGV;
  35$commit = safe_pipe_capture('git-rev-parse', '--verify', "$commit^0");
  36chomp $commit;
  37if ($?) {
  38    die "The commit reference $commit did not resolve!";
  39}
  40
  41# resolve what parent we want
  42my $parent;
  43if (@ARGV) {
  44    $parent = pop @ARGV;
  45    $parent =  safe_pipe_capture('git-rev-parse', '--verify', "$parent^0");
  46    chomp $parent;
  47    if ($?) {
  48        die "The parent reference did not resolve!";
  49    }
  50}
  51
  52# find parents from the commit itself
  53my @commit  = safe_pipe_capture('git-cat-file', 'commit', $commit);
  54my @parents;
  55my $committer;
  56my $author;
  57my $stage = 'headers'; # headers, msg
  58my $title;
  59my $msg = '';
  60
  61foreach my $line (@commit) {
  62    chomp $line;
  63    if ($stage eq 'headers' && $line eq '') {
  64        $stage = 'msg';
  65        next;
  66    }
  67
  68    if ($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 = $line;
  80        }
  81    }
  82}
  83
  84if ($parent) {
  85    my $found;
  86    # double check that it's a valid parent
  87    foreach my $p (@parents) {
  88        if ($p eq $parent) {
  89            $found = 1;
  90            last;
  91        }; # found it
  92    }
  93    die "Did not find $parent in the parents for this commit!" if !$found;
  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 $parent\n";
 103
 104# grab the commit message
 105open(MSG, ">.msg") or die "Cannot open .msg for writing";
 106if ($opt_m) {
 107    print MSG $opt_m;
 108}
 109print MSG $msg;
 110if ($opt_a) {
 111    print MSG "\n\nAuthor: $author\n";
 112    if ($author ne $committer) {
 113        print MSG "Committer: $committer\n";
 114    }
 115}
 116close MSG;
 117
 118my (@afiles, @dfiles, @mfiles, @dirs);
 119my %amodes;
 120my @files = safe_pipe_capture('git-diff-tree', '-r', $parent, $commit);
 121#print @files;
 122$? && die "Error in git-diff-tree";
 123foreach my $f (@files) {
 124    chomp $f;
 125    my @fields = split(m!\s+!, $f);
 126    if ($fields[4] eq 'A') {
 127        my $path = $fields[5];
 128        $amodes{$path} = $fields[1];
 129        push @afiles, $path;
 130        # add any needed parent directories
 131        $path = dirname $path;
 132        while (!-d $path and ! grep { $_ eq $path } @dirs) {
 133            unshift @dirs, $path;
 134            $path = dirname $path;
 135        }
 136    }
 137    if ($fields[4] eq 'M') {
 138        push @mfiles, $fields[5];
 139    }
 140    if ($fields[4] eq 'D') {
 141        push @dfiles, $fields[5];
 142    }
 143}
 144my (@binfiles, @abfiles, @dbfiles, @bfiles, @mbfiles);
 145@binfiles = grep m/^Binary files/, safe_pipe_capture('git-diff-tree', '-p', $parent, $commit);
 146map { chomp } @binfiles;
 147@abfiles = grep s/^Binary files \/dev\/null and b\/(.*) differ$/$1/, @binfiles;
 148@dbfiles = grep s/^Binary files a\/(.*) and \/dev\/null differ$/$1/, @binfiles;
 149@mbfiles = grep s/^Binary files a\/(.*) and b\/(.*) differ$/$1/, @binfiles;
 150push @bfiles, @abfiles;
 151push @bfiles, @dbfiles;
 152push @bfiles, @mbfiles;
 153push @mfiles, @mbfiles;
 154
 155$opt_v && print "The commit affects:\n ";
 156$opt_v && print join ("\n ", @afiles,@mfiles,@dfiles) . "\n\n";
 157undef @files; # don't need it anymore
 158
 159# check that the files are clean and up to date according to cvs
 160my $dirty;
 161foreach my $d (@dirs) {
 162    if (-e $d) {
 163        $dirty = 1;
 164        warn "$d exists and is not a directory!\n";
 165    }
 166}
 167foreach my $f (@afiles) {
 168    # This should return only one value
 169    if ($f =~ m,(.*)/[^/]*$,) {
 170        my $p = $1;
 171        next if (grep { $_ eq $p } @dirs);
 172    }
 173    my @status = grep(m/^File/,  safe_pipe_capture('cvs', '-q', 'status' ,$f));
 174    if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
 175    if (-d dirname $f and $status[0] !~ m/Status: Unknown$/
 176        and $status[0] !~ m/^File: no file /) {
 177        $dirty = 1;
 178        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";
 179        warn "Status was: $status[0]\n";
 180    }
 181}
 182
 183foreach my $f (@mfiles, @dfiles) {
 184    # TODO:we need to handle removed in cvs
 185    my @status = grep(m/^File/,  safe_pipe_capture('cvs', '-q', 'status' ,$f));
 186    if (@status > 1) { warn 'Strange! cvs status returned more than one line?'};
 187    unless ($status[0] =~ m/Status: Up-to-date$/) {
 188        $dirty = 1;
 189        warn "File $f not up to date in your CVS checkout!\n";
 190    }
 191}
 192if ($dirty) {
 193    if ($opt_f) {       warn "The tree is not clean -- forced merge\n";
 194        $dirty = 0;
 195    } else {
 196        die "Exiting: your CVS tree is not clean for this merge.";
 197    }
 198}
 199
 200###
 201### NOTE: if you are planning to die() past this point
 202###       you MUST call cleanupcvs(@files) before die()
 203###
 204
 205
 206print "Creating new directories\n";
 207foreach my $d (@dirs) {
 208    unless (mkdir $d) {
 209        warn "Could not mkdir $d: $!";
 210        $dirty = 1;
 211    }
 212    `cvs add $d`;
 213    if ($?) {
 214        $dirty = 1;
 215        warn "Failed to cvs add directory $d -- you may need to do it manually";
 216    }
 217}
 218
 219print "'Patching' binary files\n";
 220
 221foreach my $f (@bfiles) {
 222    # check that the file in cvs matches the "old" file
 223    # extract the file to $tmpdir and compare with cmp
 224    if (not(grep { $_ eq $f } @afiles)) {
 225        my $tree = safe_pipe_capture('git-rev-parse', "$parent^{tree}");
 226        chomp $tree;
 227        my $blob = `git-ls-tree $tree "$f" | cut -f 1 | cut -d ' ' -f 3`;
 228        chomp $blob;
 229        `git-cat-file blob $blob > $tmpdir/blob`;
 230        if (system('cmp', '-s', $f, "$tmpdir/blob")) {
 231            warn "Binary file $f in CVS does not match parent.\n";
 232            if (not $opt_f) {
 233                $dirty = 1;
 234                next;
 235            }
 236        }
 237    }
 238    if (not(grep { $_ eq $f } @dfiles)) {
 239        my $tree = safe_pipe_capture('git-rev-parse', "$commit^{tree}");
 240        chomp $tree;
 241        my $blob = `git-ls-tree $tree "$f" | cut -f 1 | cut -d ' ' -f 3`;
 242        chomp $blob;
 243        # replace with the new file
 244        `git-cat-file blob $blob > $f`;
 245    }
 246
 247    # TODO: something smart with file modes
 248
 249}
 250if ($dirty) {
 251    cleanupcvs(@files);
 252    die "Exiting: Binary files in CVS do not match parent";
 253}
 254
 255## apply non-binary changes
 256my $fuzz = $opt_p ? 0 : 2;
 257
 258print "Patching non-binary files\n";
 259
 260if (scalar(@afiles)+scalar(@dfiles)+scalar(@mfiles) != scalar(@bfiles)) {
 261    print `(git-diff-tree -p $parent -p $commit | patch -p1 -F $fuzz ) 2>&1`;
 262}
 263
 264my $dirtypatch = 0;
 265if (($? >> 8) == 2) {
 266    cleanupcvs(@files);
 267    die "Exiting: Patch reported serious trouble -- you will have to apply this patch manually";
 268} elsif (($? >> 8) == 1) { # some hunks failed to apply
 269    $dirtypatch = 1;
 270}
 271
 272foreach my $f (@afiles) {
 273    set_new_file_permissions($f, $amodes{$f});
 274    if (grep { $_ eq $f } @bfiles) {
 275      system('cvs', 'add','-kb',$f);
 276    } else {
 277      system('cvs', 'add', $f);
 278    }
 279    if ($?) {
 280        $dirty = 1;
 281        warn "Failed to cvs add $f -- you may need to do it manually";
 282    }
 283}
 284
 285foreach my $f (@dfiles) {
 286    system('cvs', 'rm', '-f', $f);
 287    if ($?) {
 288        $dirty = 1;
 289        warn "Failed to cvs rm -f $f -- you may need to do it manually";
 290    }
 291}
 292
 293print "Commit to CVS\n";
 294print "Patch: $title\n";
 295my $commitfiles = join(' ', @afiles, @mfiles, @dfiles);
 296my $cmd = "cvs commit -F .msg $commitfiles";
 297
 298if ($dirtypatch) {
 299    print "NOTE: One or more hunks failed to apply cleanly.\n";
 300    print "Resolve the conflicts and then commit using:\n";
 301    print "\n    $cmd\n\n";
 302    exit(1);
 303}
 304
 305
 306if ($opt_c) {
 307    print "Autocommit\n  $cmd\n";
 308    print safe_pipe_capture('cvs', 'commit', '-F', '.msg', @afiles, @mfiles, @dfiles);
 309    if ($?) {
 310        cleanupcvs(@files);
 311        die "Exiting: The commit did not succeed";
 312    }
 313    print "Committed successfully to CVS\n";
 314} else {
 315    print "Ready for you to commit, just run:\n\n   $cmd\n";
 316}
 317sub usage {
 318        print STDERR <<END;
 319Usage: GIT_DIR=/path/to/.git ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-m msgprefix] [ parent ] commit
 320END
 321        exit(1);
 322}
 323
 324# ensure cvs is clean before we die
 325sub cleanupcvs {
 326    my @files = @_;
 327    foreach my $f (@files) {
 328        system('cvs', '-q', 'update', '-C', $f);
 329        if ($?) {
 330            warn "Warning! Failed to cleanup state of $f\n";
 331        }
 332    }
 333}
 334
 335# An alternative to `command` that allows input to be passed as an array
 336# to work around shell problems with weird characters in arguments
 337# if the exec returns non-zero we die
 338sub safe_pipe_capture {
 339    my @output;
 340    if (my $pid = open my $child, '-|') {
 341        @output = (<$child>);
 342        close $child or die join(' ',@_).": $! $?";
 343    } else {
 344        exec(@_) or die "$! $?"; # exec() can fail the executable can't be found
 345    }
 346    return wantarray ? @output : join('',@output);
 347}
 348
 349# For any file we want to add to cvs, we must first set its permissions
 350# properly, *before* the "cvs add ..." command.  Otherwise, it is impossible
 351# to change the permission of the file in the CVS repository using only cvs
 352# commands.  This should be fixed in cvs-1.12.14.
 353sub set_new_file_permissions {
 354    my ($file, $perm) = @_;
 355    chmod oct($perm), $file
 356      or die "failed to set permissions of \"$file\": $!\n";
 357}