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Diffstat (limited to 'perl/Git/SVN/Fetcher.pm')
| -rw-r--r-- | perl/Git/SVN/Fetcher.pm | 622 |
1 files changed, 622 insertions, 0 deletions
diff --git a/perl/Git/SVN/Fetcher.pm b/perl/Git/SVN/Fetcher.pm new file mode 100644 index 0000000..968309e --- /dev/null +++ b/perl/Git/SVN/Fetcher.pm @@ -0,0 +1,622 @@ +package Git::SVN::Fetcher; +use vars qw/@ISA $_ignore_regex $_include_regex $_preserve_empty_dirs + $_placeholder_filename @deleted_gpath %added_placeholder + $repo_id/; +use strict; +use warnings $ENV{GIT_PERL_FATAL_WARNINGS} ? qw(FATAL all) : (); +use SVN::Delta; +use Carp qw/croak/; +use File::Basename qw/dirname/; +use Git qw/command command_oneline command_noisy command_output_pipe + command_input_pipe command_close_pipe + command_bidi_pipe command_close_bidi_pipe + get_record/; +BEGIN { + @ISA = qw(SVN::Delta::Editor); +} + +# file baton members: path, mode_a, mode_b, pool, fh, blob, base +sub new { + my ($class, $git_svn, $switch_path) = @_; + my $self = SVN::Delta::Editor->new; + bless $self, $class; + if (exists $git_svn->{last_commit}) { + $self->{c} = $git_svn->{last_commit}; + $self->{empty_symlinks} = + _mark_empty_symlinks($git_svn, $switch_path); + } + + # some options are read globally, but can be overridden locally + # per [svn-remote "..."] section. Command-line options will *NOT* + # override options set in an [svn-remote "..."] section + $repo_id = $git_svn->{repo_id}; + my $k = "svn-remote.$repo_id.ignore-paths"; + my $v = eval { command_oneline('config', '--get', $k) }; + $self->{ignore_regex} = $v; + + $k = "svn-remote.$repo_id.include-paths"; + $v = eval { command_oneline('config', '--get', $k) }; + $self->{include_regex} = $v; + + $k = "svn-remote.$repo_id.preserve-empty-dirs"; + $v = eval { command_oneline('config', '--get', '--bool', $k) }; + if ($v && $v eq 'true') { + $_preserve_empty_dirs = 1; + $k = "svn-remote.$repo_id.placeholder-filename"; + $v = eval { command_oneline('config', '--get', $k) }; + $_placeholder_filename = $v; + } + + # Load the list of placeholder files added during previous invocations. + $k = "svn-remote.$repo_id.added-placeholder"; + $v = eval { command_oneline('config', '--get-all', $k) }; + if ($_preserve_empty_dirs && $v) { + # command() prints errors to stderr, so we only call it if + # command_oneline() succeeded. + my @v = command('config', '--get-all', $k); + $added_placeholder{ dirname($_) } = $_ foreach @v; + } + + $self->{empty} = {}; + $self->{dir_prop} = {}; + $self->{file_prop} = {}; + $self->{absent_dir} = {}; + $self->{absent_file} = {}; + require Git::IndexInfo; + $self->{gii} = $git_svn->tmp_index_do(sub { Git::IndexInfo->new }); + $self->{pathnameencoding} = Git::config('svn.pathnameencoding'); + $self; +} + +# this uses the Ra object, so it must be called before do_{switch,update}, +# not inside them (when the Git::SVN::Fetcher object is passed) to +# do_{switch,update} +sub _mark_empty_symlinks { + my ($git_svn, $switch_path) = @_; + my $bool = Git::config_bool('svn.brokenSymlinkWorkaround'); + return {} if (!defined($bool)) || (defined($bool) && ! $bool); + + my %ret; + my ($rev, $cmt) = $git_svn->last_rev_commit; + return {} unless ($rev && $cmt); + + # allow the warning to be printed for each revision we fetch to + # ensure the user sees it. The user can also disable the workaround + # on the repository even while git svn is running and the next + # revision fetched will skip this expensive function. + my $printed_warning; + chomp(my $empty_blob = `git hash-object -t blob --stdin < /dev/null`); + my ($ls, $ctx) = command_output_pipe(qw/ls-tree -r -z/, $cmt); + my $pfx = defined($switch_path) ? $switch_path : $git_svn->path; + $pfx .= '/' if length($pfx); + while (defined($_ = get_record($ls, "\0"))) { + s/\A100644 blob $empty_blob\t//o or next; + unless ($printed_warning) { + print STDERR "Scanning for empty symlinks, ", + "this may take a while if you have ", + "many empty files\n", + "You may disable this with `", + "git config svn.brokenSymlinkWorkaround ", + "false'.\n", + "This may be done in a different ", + "terminal without restarting ", + "git svn\n"; + $printed_warning = 1; + } + my $path = $_; + my (undef, $props) = + $git_svn->ra->get_file($pfx.$path, $rev, undef); + if ($props->{'svn:special'}) { + $ret{$path} = 1; + } + } + command_close_pipe($ls, $ctx); + \%ret; +} + +# returns true if a given path is inside a ".git" directory +sub in_dot_git { + $_[0] =~ m{(?:^|/)\.git(?:/|$)}; +} + +# return value: 0 -- don't ignore, 1 -- ignore +# This will also check whether the path is explicitly included +sub is_path_ignored { + my ($self, $path) = @_; + return 1 if in_dot_git($path); + return 1 if defined($self->{ignore_regex}) && + $path =~ m!$self->{ignore_regex}!; + return 0 if defined($self->{include_regex}) && + $path =~ m!$self->{include_regex}!; + return 0 if defined($_include_regex) && + $path =~ m!$_include_regex!; + return 1 if defined($self->{include_regex}); + return 1 if defined($_include_regex); + return 0 unless defined($_ignore_regex); + return 1 if $path =~ m!$_ignore_regex!o; + return 0; +} + +sub set_path_strip { + my ($self, $path) = @_; + $self->{path_strip} = qr/^\Q$path\E(\/|$)/ if length $path; +} + +sub open_root { + { path => '' }; +} + +sub open_directory { + my ($self, $path, $pb, $rev) = @_; + { path => $path }; +} + +sub git_path { + my ($self, $path) = @_; + if (my $enc = $self->{pathnameencoding}) { + require Encode; + Encode::from_to($path, 'UTF-8', $enc); + } + if ($self->{path_strip}) { + $path =~ s!$self->{path_strip}!! or + die "Failed to strip path '$path' ($self->{path_strip})\n"; + } + $path; +} + +sub delete_entry { + my ($self, $path, $rev, $pb) = @_; + return undef if $self->is_path_ignored($path); + + my $gpath = $self->git_path($path); + return undef if ($gpath eq ''); + + # remove entire directories. + my ($tree) = (command('ls-tree', '-z', $self->{c}, "./$gpath") + =~ /\A040000 tree ($::oid)\t\Q$gpath\E\0/); + if ($tree) { + my ($ls, $ctx) = command_output_pipe(qw/ls-tree + -r --name-only -z/, + $tree); + while (defined($_ = get_record($ls, "\0"))) { + my $rmpath = "$gpath/$_"; + $self->{gii}->remove($rmpath); + print "\tD\t$rmpath\n" unless $::_q; + } + print "\tD\t$gpath/\n" unless $::_q; + command_close_pipe($ls, $ctx); + } else { + $self->{gii}->remove($gpath); + print "\tD\t$gpath\n" unless $::_q; + } + # Don't add to @deleted_gpath if we're deleting a placeholder file. + push @deleted_gpath, $gpath unless $added_placeholder{dirname($path)}; + $self->{empty}->{$path} = 0; + undef; +} + +sub open_file { + my ($self, $path, $pb, $rev) = @_; + my ($mode, $blob); + + goto out if $self->is_path_ignored($path); + + my $gpath = $self->git_path($path); + ($mode, $blob) = (command('ls-tree', '-z', $self->{c}, "./$gpath") + =~ /\A(\d{6}) blob ($::oid)\t\Q$gpath\E\0/); + unless (defined $mode && defined $blob) { + die "$path was not found in commit $self->{c} (r$rev)\n"; + } + if ($mode eq '100644' && $self->{empty_symlinks}->{$path}) { + $mode = '120000'; + } +out: + { path => $path, mode_a => $mode, mode_b => $mode, blob => $blob, + pool => SVN::Pool->new, action => 'M' }; +} + +sub add_file { + my ($self, $path, $pb, $cp_path, $cp_rev) = @_; + my $mode; + + if (!$self->is_path_ignored($path)) { + my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#); + delete $self->{empty}->{$dir}; + $mode = '100644'; + + if ($added_placeholder{$dir}) { + # Remove our placeholder file, if we created one. + delete_entry($self, $added_placeholder{$dir}) + unless $path eq $added_placeholder{$dir}; + delete $added_placeholder{$dir} + } + } + + { path => $path, mode_a => $mode, mode_b => $mode, + pool => SVN::Pool->new, action => 'A' }; +} + +sub add_directory { + my ($self, $path, $cp_path, $cp_rev) = @_; + goto out if $self->is_path_ignored($path); + my $gpath = $self->git_path($path); + if ($gpath eq '') { + my ($ls, $ctx) = command_output_pipe(qw/ls-tree + -r --name-only -z/, + $self->{c}); + while (defined($_ = get_record($ls, "\0"))) { + $self->{gii}->remove($_); + print "\tD\t$_\n" unless $::_q; + push @deleted_gpath, $gpath; + } + command_close_pipe($ls, $ctx); + $self->{empty}->{$path} = 0; + } + my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#); + delete $self->{empty}->{$dir}; + $self->{empty}->{$path} = 1; + + if ($added_placeholder{$dir}) { + # Remove our placeholder file, if we created one. + delete_entry($self, $added_placeholder{$dir}); + delete $added_placeholder{$dir} + } + +out: + { path => $path }; +} + +sub change_dir_prop { + my ($self, $db, $prop, $value) = @_; + return undef if $self->is_path_ignored($db->{path}); + $self->{dir_prop}->{$db->{path}} ||= {}; + $self->{dir_prop}->{$db->{path}}->{$prop} = $value; + undef; +} + +sub absent_directory { + my ($self, $path, $pb) = @_; + return undef if $self->is_path_ignored($path); + $self->{absent_dir}->{$pb->{path}} ||= []; + push @{$self->{absent_dir}->{$pb->{path}}}, $path; + undef; +} + +sub absent_file { + my ($self, $path, $pb) = @_; + return undef if $self->is_path_ignored($path); + $self->{absent_file}->{$pb->{path}} ||= []; + push @{$self->{absent_file}->{$pb->{path}}}, $path; + undef; +} + +sub change_file_prop { + my ($self, $fb, $prop, $value) = @_; + return undef if $self->is_path_ignored($fb->{path}); + if ($prop eq 'svn:executable') { + if ($fb->{mode_b} != 120000) { + $fb->{mode_b} = defined $value ? 100755 : 100644; + } + } elsif ($prop eq 'svn:special') { + $fb->{mode_b} = defined $value ? 120000 : 100644; + } else { + $self->{file_prop}->{$fb->{path}} ||= {}; + $self->{file_prop}->{$fb->{path}}->{$prop} = $value; + } + undef; +} + +sub apply_textdelta { + my ($self, $fb, $exp) = @_; + return undef if $self->is_path_ignored($fb->{path}); + my $suffix = 0; + ++$suffix while $::_repository->temp_is_locked("svn_delta_${$}_$suffix"); + my $fh = $::_repository->temp_acquire("svn_delta_${$}_$suffix"); + # $fh gets auto-closed() by SVN::TxDelta::apply(), + # (but $base does not,) so dup() it for reading in close_file + open my $dup, '<&', $fh or croak $!; + my $base = $::_repository->temp_acquire("git_blob_${$}_$suffix"); + # close_file may call temp_acquire on 'svn_hash', but because of the + # call chain, if the temp_acquire call from close_file ends up being the + # call that first creates the 'svn_hash' temp file, then the FileHandle + # that's created as a result will end up in an SVN::Pool that we clear + # in SVN::Ra::gs_fetch_loop_common. Avoid that by making sure the + # 'svn_hash' FileHandle is already created before close_file is called. + my $tmp_fh = $::_repository->temp_acquire('svn_hash'); + $::_repository->temp_release($tmp_fh, 1); + + if ($fb->{blob}) { + my ($base_is_link, $size); + + if ($fb->{mode_a} eq '120000' && + ! $self->{empty_symlinks}->{$fb->{path}}) { + print $base 'link ' or die "print $!\n"; + $base_is_link = 1; + } + retry: + $size = $::_repository->cat_blob($fb->{blob}, $base); + die "Failed to read object $fb->{blob}" if ($size < 0); + + if (defined $exp) { + seek $base, 0, 0 or croak $!; + my $got = ::md5sum($base); + if ($got ne $exp) { + my $err = "Checksum mismatch: ". + "$fb->{path} $fb->{blob}\n" . + "expected: $exp\n" . + " got: $got\n"; + if ($base_is_link) { + warn $err, + "Retrying... (possibly ", + "a bad symlink from SVN)\n"; + $::_repository->temp_reset($base); + $base_is_link = 0; + goto retry; + } + die $err; + } + } + } + seek $base, 0, 0 or croak $!; + $fb->{fh} = $fh; + $fb->{base} = $base; + [ SVN::TxDelta::apply($base, $dup, undef, $fb->{path}, $fb->{pool}) ]; +} + +sub close_file { + my ($self, $fb, $exp) = @_; + return undef if $self->is_path_ignored($fb->{path}); + + my $hash; + my $path = $self->git_path($fb->{path}); + if (my $fh = $fb->{fh}) { + if (defined $exp) { + seek($fh, 0, 0) or croak $!; + my $got = ::md5sum($fh); + if ($got ne $exp) { + die "Checksum mismatch: $path\n", + "expected: $exp\n got: $got\n"; + } + } + if ($fb->{mode_b} == 120000) { + sysseek($fh, 0, 0) or croak $!; + my $rd = sysread($fh, my $buf, 5); + + if (!defined $rd) { + croak "sysread: $!\n"; + } elsif ($rd == 0) { + warn "$path has mode 120000", + " but it points to nothing\n", + "converting to an empty file with mode", + " 100644\n"; + $fb->{mode_b} = '100644'; + } elsif ($buf ne 'link ') { + warn "$path has mode 120000", + " but is not a link\n"; + } else { + my $tmp_fh = $::_repository->temp_acquire( + 'svn_hash'); + my $res; + while ($res = sysread($fh, my $str, 1024)) { + my $out = syswrite($tmp_fh, $str, $res); + defined($out) && $out == $res + or croak("write ", + Git::temp_path($tmp_fh), + ": $!\n"); + } + defined $res or croak $!; + + ($fh, $tmp_fh) = ($tmp_fh, $fh); + Git::temp_release($tmp_fh, 1); + } + } + + $hash = $::_repository->hash_and_insert_object( + Git::temp_path($fh)); + $hash =~ /^$::oid$/ or die "not an object ID: $hash\n"; + + Git::temp_release($fb->{base}, 1); + Git::temp_release($fh, 1); + } else { + $hash = $fb->{blob} or die "no blob information\n"; + } + $fb->{pool}->clear; + $self->{gii}->update($fb->{mode_b}, $hash, $path) or croak $!; + print "\t$fb->{action}\t$path\n" if $fb->{action} && ! $::_q; + undef; +} + +sub abort_edit { + my $self = shift; + $self->{nr} = $self->{gii}->{nr}; + delete $self->{gii}; + $self->SUPER::abort_edit(@_); +} + +sub close_edit { + my $self = shift; + + if ($_preserve_empty_dirs) { + my @empty_dirs; + + # Any entry flagged as empty that also has an associated + # dir_prop represents a newly created empty directory. + foreach my $i (keys %{$self->{empty}}) { + push @empty_dirs, $i if exists $self->{dir_prop}->{$i}; + } + + # Search for directories that have become empty due subsequent + # file deletes. + push @empty_dirs, $self->find_empty_directories(); + + # Finally, add a placeholder file to each empty directory. + $self->add_placeholder_file($_) foreach (@empty_dirs); + + $self->stash_placeholder_list(); + } + + $self->{git_commit_ok} = 1; + $self->{nr} = $self->{gii}->{nr}; + delete $self->{gii}; + $self->SUPER::close_edit(@_); +} + +sub find_empty_directories { + my ($self) = @_; + my @empty_dirs; + my %dirs = map { dirname($_) => 1 } @deleted_gpath; + + foreach my $dir (sort keys %dirs) { + next if $dir eq "."; + + # If there have been any additions to this directory, there is + # no reason to check if it is empty. + my $skip_added = 0; + foreach my $t (qw/dir_prop file_prop/) { + foreach my $path (keys %{ $self->{$t} }) { + if (exists $self->{$t}->{dirname($path)}) { + $skip_added = 1; + last; + } + } + last if $skip_added; + } + next if $skip_added; + + # Use `git ls-tree` to get the filenames of this directory + # that existed prior to this particular commit. + my $ls = command('ls-tree', '-z', '--name-only', + $self->{c}, "$dir/"); + my %files = map { $_ => 1 } split(/\0/, $ls); + + # Remove the filenames that were deleted during this commit. + delete $files{$_} foreach (@deleted_gpath); + + # Report the directory if there are no filenames left. + push @empty_dirs, $dir unless (scalar %files); + } + @empty_dirs; +} + +sub add_placeholder_file { + my ($self, $dir) = @_; + my $path = "$dir/$_placeholder_filename"; + my $gpath = $self->git_path($path); + + my $fh = $::_repository->temp_acquire($gpath); + my $hash = $::_repository->hash_and_insert_object(Git::temp_path($fh)); + Git::temp_release($fh, 1); + $self->{gii}->update('100644', $hash, $gpath) or croak $!; + + # The directory should no longer be considered empty. + delete $self->{empty}->{$dir} if exists $self->{empty}->{$dir}; + + # Keep track of any placeholder files we create. + $added_placeholder{$dir} = $path; +} + +sub stash_placeholder_list { + my ($self) = @_; + my $k = "svn-remote.$repo_id.added-placeholder"; + my $v = eval { command_oneline('config', '--get-all', $k) }; + command_noisy('config', '--unset-all', $k) if $v; + foreach (values %added_placeholder) { + command_noisy('config', '--add', $k, $_); + } +} + +1; +__END__ + +=head1 NAME + +Git::SVN::Fetcher - tree delta consumer for "git svn fetch" + +=head1 SYNOPSIS + + use SVN::Core; + use SVN::Ra; + use Git::SVN; + use Git::SVN::Fetcher; + use Git; + + my $gs = Git::SVN->find_by_url($url); + my $ra = SVN::Ra->new(url => $url); + my $editor = Git::SVN::Fetcher->new($gs); + my $reporter = $ra->do_update($SVN::Core::INVALID_REVNUM, '', + 1, $editor); + $reporter->set_path('', $old_rev, 0); + $reporter->finish_report; + my $tree = $gs->tmp_index_do(sub { command_oneline('write-tree') }); + + foreach my $path (keys %{$editor->{dir_prop}) { + my $props = $editor->{dir_prop}{$path}; + foreach my $prop (keys %$props) { + print "property $prop at $path changed to $props->{$prop}\n"; + } + } + foreach my $path (keys %{$editor->{empty}) { + my $action = $editor->{empty}{$path} ? 'added' : 'removed'; + print "empty directory $path $action\n"; + } + foreach my $path (keys %{$editor->{file_prop}) { ... } + foreach my $parent (keys %{$editor->{absent_dir}}) { + my @children = @{$editor->{abstent_dir}{$parent}}; + print "cannot fetch directory $parent/$_: not authorized?\n" + foreach @children; + } + foreach my $parent (keys %{$editor->{absent_file}) { ... } + +=head1 DESCRIPTION + +This is a subclass of C<SVN::Delta::Editor>, which means it implements +callbacks to act as a consumer of Subversion tree deltas. This +particular implementation of those callbacks is meant to store +information about the resulting content which B<git svn fetch> could +use to populate new commits and new entries for F<unhandled.log>. +More specifically: + +=over + +=item * Additions, removals, and modifications of files are propagated +to git-svn's index file F<$GIT_DIR/svn/$refname/index> using +B<git update-index>. + +=item * Changes in Subversion path properties are recorded in the +C<dir_prop> and C<file_prop> fields (which are hashes). + +=item * Addition and removal of empty directories are indicated by +entries with value 1 and 0 respectively in the C<empty> hash. + +=item * Paths that are present but cannot be conveyed (presumably due +to permissions) are recorded in the C<absent_file> and +C<absent_dirs> hashes. For each key, the corresponding value is +a list of paths under that directory that were present but +could not be conveyed. + +=back + +The interface is unstable. Do not use this module unless you are +developing git-svn. + +=head1 DEPENDENCIES + +L<SVN::Delta> from the Subversion perl bindings, +the core L<Carp> and L<File::Basename> modules, +and git's L<Git> helper module. + +C<Git::SVN::Fetcher> has not been tested using callers other than +B<git-svn> itself. + +=head1 SEE ALSO + +L<SVN::Delta>, +L<Git::SVN::Editor>. + +=head1 INCOMPATIBILITIES + +None reported. + +=head1 BUGS + +None. |