#!/usr/bin/perl

####
#### This application is a CVS emulation layer for git.
#### It is intended for clients to connect over SSH.
#### See the documentation for more details.
####
#### Copyright The Open University UK - 2006.
####
#### Authors: Martyn Smith    <martyn@catalyst.net.nz>
####          Martin Langhoff <martin@catalyst.net.nz>
####
####
#### Released under the GNU Public License, version 2.
####
####

use strict;
use warnings;
use bytes;

use Fcntl;
use File::Temp qw/tempdir tempfile/;
use File::Basename;

my $log = GITCVS::log->new();
my $cfg;

my $DATE_LIST = {
    Jan => "01",
    Feb => "02",
    Mar => "03",
    Apr => "04",
    May => "05",
    Jun => "06",
    Jul => "07",
    Aug => "08",
    Sep => "09",
    Oct => "10",
    Nov => "11",
    Dec => "12",
};

# Enable autoflush for STDOUT (otherwise the whole thing falls apart)
$| = 1;

#### Definition and mappings of functions ####

my $methods = {
    'Root'            => \&req_Root,
    'Valid-responses' => \&req_Validresponses,
    'valid-requests'  => \&req_validrequests,
    'Directory'       => \&req_Directory,
    'Entry'           => \&req_Entry,
    'Modified'        => \&req_Modified,
    'Unchanged'       => \&req_Unchanged,
    'Questionable'    => \&req_Questionable,
    'Argument'        => \&req_Argument,
    'Argumentx'       => \&req_Argument,
    'expand-modules'  => \&req_expandmodules,
    'add'             => \&req_add,
    'remove'          => \&req_remove,
    'co'              => \&req_co,
    'update'          => \&req_update,
    'ci'              => \&req_ci,
    'diff'            => \&req_diff,
    'log'             => \&req_log,
    'rlog'            => \&req_log,
    'tag'             => \&req_CATCHALL,
    'status'          => \&req_status,
    'admin'           => \&req_CATCHALL,
    'history'         => \&req_CATCHALL,
    'watchers'        => \&req_CATCHALL,
    'editors'         => \&req_CATCHALL,
    'annotate'        => \&req_annotate,
    'Global_option'   => \&req_Globaloption,
    #'annotate'        => \&req_CATCHALL,
};

##############################################


# $state holds all the bits of information the clients sends us that could
# potentially be useful when it comes to actually _doing_ something.
my $state = { prependdir => '' };
$log->info("--------------- STARTING -----------------");

my $TEMP_DIR = tempdir( CLEANUP => 1 );
$log->debug("Temporary directory is '$TEMP_DIR'");

# if we are called with a pserver argument,
# deal with the authentication cat before entering the
# main loop
if (@ARGV && $ARGV[0] eq 'pserver') {
    my $line = <STDIN>; chomp $line;
    unless( $line eq 'BEGIN AUTH REQUEST') {
       die "E Do not understand $line - expecting BEGIN AUTH REQUEST\n";
    }
    $line = <STDIN>; chomp $line;
    req_Root('root', $line) # reuse Root
       or die "E Invalid root $line \n";
    $line = <STDIN>; chomp $line;
    unless ($line eq 'anonymous') {
       print "E Only anonymous user allowed via pserver\n";
       print "I HATE YOU\n";
    }
    $line = <STDIN>; chomp $line;    # validate the password?
    $line = <STDIN>; chomp $line;
    unless ($line eq 'END AUTH REQUEST') {
       die "E Do not understand $line -- expecting END AUTH REQUEST\n";
    }
    print "I LOVE YOU\n";
    # and now back to our regular programme...
}

# Keep going until the client closes the connection
while (<STDIN>)
{
    chomp;

    # Check to see if we've seen this method, and call appropriate function.
    if ( /^([\w-]+)(?:\s+(.*))?$/ and defined($methods->{$1}) )
    {
        # use the $methods hash to call the appropriate sub for this command
        #$log->info("Method : $1");
        &{$methods->{$1}}($1,$2);
    } else {
        # log fatal because we don't understand this function. If this happens
        # we're fairly screwed because we don't know if the client is expecting
        # a response. If it is, the client will hang, we'll hang, and the whole
        # thing will be custard.
        $log->fatal("Don't understand command $_\n");
        die("Unknown command $_");
    }
}

$log->debug("Processing time : user=" . (times)[0] . " system=" . (times)[1]);
$log->info("--------------- FINISH -----------------");

# Magic catchall method.
#    This is the method that will handle all commands we haven't yet
#    implemented. It simply sends a warning to the log file indicating a
#    command that hasn't been implemented has been invoked.
sub req_CATCHALL
{
    my ( $cmd, $data ) = @_;
    $log->warn("Unhandled command : req_$cmd : $data");
}


# Root pathname \n
#     Response expected: no. Tell the server which CVSROOT to use. Note that
#     pathname is a local directory and not a fully qualified CVSROOT variable.
#     pathname must already exist; if creating a new root, use the init
#     request, not Root. pathname does not include the hostname of the server,
#     how to access the server, etc.; by the time the CVS protocol is in use,
#     connection, authentication, etc., are already taken care of. The Root
#     request must be sent only once, and it must be sent before any requests
#     other than Valid-responses, valid-requests, UseUnchanged, Set or init.
sub req_Root
{
    my ( $cmd, $data ) = @_;
    $log->debug("req_Root : $data");

    $state->{CVSROOT} = $data;

    $ENV{GIT_DIR} = $state->{CVSROOT} . "/";
    unless (-d $ENV{GIT_DIR} && -e $ENV{GIT_DIR}.'HEAD') {
       print "E $ENV{GIT_DIR} does not seem to be a valid GIT repository\n";
        print "E \n";
        print "error 1 $ENV{GIT_DIR} is not a valid repository\n";
       return 0;
    }

    my @gitvars = `git-config -l`;
    if ($?) {
       print "E problems executing git-config on the server -- this is not a git repository or the PATH is not set correctly.\n";
        print "E \n";
        print "error 1 - problem executing git-config\n";
       return 0;
    }
    foreach my $line ( @gitvars )
    {
        next unless ( $line =~ /^(.*?)\.(.*?)=(.*)$/ );
        $cfg->{$1}{$2} = $3;
    }

    unless ( defined ( $cfg->{gitcvs}{enabled} ) and $cfg->{gitcvs}{enabled} =~ /^\s*(1|true|yes)\s*$/i )
    {
        print "E GITCVS emulation needs to be enabled on this repo\n";
        print "E the repo config file needs a [gitcvs] section added, and the parameter 'enabled' set to 1\n";
        print "E \n";
        print "error 1 GITCVS emulation disabled\n";
        return 0;
    }

    if ( defined ( $cfg->{gitcvs}{logfile} ) )
    {
        $log->setfile($cfg->{gitcvs}{logfile});
    } else {
        $log->nofile();
    }

    return 1;
}

# Global_option option \n
#     Response expected: no. Transmit one of the global options `-q', `-Q',
#     `-l', `-t', `-r', or `-n'. option must be one of those strings, no
#     variations (such as combining of options) are allowed. For graceful
#     handling of valid-requests, it is probably better to make new global
#     options separate requests, rather than trying to add them to this
#     request.
sub req_Globaloption
{
    my ( $cmd, $data ) = @_;
    $log->debug("req_Globaloption : $data");
    $state->{globaloptions}{$data} = 1;
}

# Valid-responses request-list \n
#     Response expected: no. Tell the server what responses the client will
#     accept. request-list is a space separated list of tokens.
sub req_Validresponses
{
    my ( $cmd, $data ) = @_;
    $log->debug("req_Validresponses : $data");

    # TODO : re-enable this, currently it's not particularly useful
    #$state->{validresponses} = [ split /\s+/, $data ];
}

# valid-requests \n
#     Response expected: yes. Ask the server to send back a Valid-requests
#     response.
sub req_validrequests
{
    my ( $cmd, $data ) = @_;

    $log->debug("req_validrequests");

    $log->debug("SEND : Valid-requests " . join(" ",keys %$methods));
    $log->debug("SEND : ok");

    print "Valid-requests " . join(" ",keys %$methods) . "\n";
    print "ok\n";
}

# Directory local-directory \n
#     Additional data: repository \n. Response expected: no. Tell the server
#     what directory to use. The repository should be a directory name from a
#     previous server response. Note that this both gives a default for Entry
#     and Modified and also for ci and the other commands; normal usage is to
#     send Directory for each directory in which there will be an Entry or
#     Modified, and then a final Directory for the original directory, then the
#     command. The local-directory is relative to the top level at which the
#     command is occurring (i.e. the last Directory which is sent before the
#     command); to indicate that top level, `.' should be sent for
#     local-directory.
sub req_Directory
{
    my ( $cmd, $data ) = @_;

    my $repository = <STDIN>;
    chomp $repository;


    $state->{localdir} = $data;
    $state->{repository} = $repository;
    $state->{path} = $repository;
    $state->{path} =~ s/^$state->{CVSROOT}\///;
    $state->{module} = $1 if ($state->{path} =~ s/^(.*?)(\/|$)//);
    $state->{path} .= "/" if ( $state->{path} =~ /\S/ );

    $state->{directory} = $state->{localdir};
    $state->{directory} = "" if ( $state->{directory} eq "." );
    $state->{directory} .= "/" if ( $state->{directory} =~ /\S/ );

    if ( (not defined($state->{prependdir}) or $state->{prependdir} eq '') and $state->{localdir} eq "." and $state->{path} =~ /\S/ )
    {
        $log->info("Setting prepend to '$state->{path}'");
        $state->{prependdir} = $state->{path};
        foreach my $entry ( keys %{$state->{entries}} )
        {
            $state->{entries}{$state->{prependdir} . $entry} = $state->{entries}{$entry};
            delete $state->{entries}{$entry};
        }
    }

    if ( defined ( $state->{prependdir} ) )
    {
        $log->debug("Prepending '$state->{prependdir}' to state|directory");
        $state->{directory} = $state->{prependdir} . $state->{directory}
    }
    $log->debug("req_Directory : localdir=$data repository=$repository path=$state->{path} directory=$state->{directory} module=$state->{module}");
}

# Entry entry-line \n
#     Response expected: no. Tell the server what version of a file is on the
#     local machine. The name in entry-line is a name relative to the directory
#     most recently specified with Directory. If the user is operating on only
#     some files in a directory, Entry requests for only those files need be
#     included. If an Entry request is sent without Modified, Is-modified, or
#     Unchanged, it means the file is lost (does not exist in the working
#     directory). If both Entry and one of Modified, Is-modified, or Unchanged
#     are sent for the same file, Entry must be sent first. For a given file,
#     one can send Modified, Is-modified, or Unchanged, but not more than one
#     of these three.
sub req_Entry
{
    my ( $cmd, $data ) = @_;

    #$log->debug("req_Entry : $data");

    my @data = split(/\//, $data);

    $state->{entries}{$state->{directory}.$data[1]} = {
        revision    => $data[2],
        conflict    => $data[3],
        options     => $data[4],
        tag_or_date => $data[5],
    };

    $log->info("Received entry line '$data' => '" . $state->{directory} . $data[1] . "'");
}

# Questionable filename \n
#     Response expected: no. Additional data: no. Tell the server to check
#     whether filename should be ignored, and if not, next time the server
#     sends responses, send (in a M response) `?' followed by the directory and
#     filename. filename must not contain `/'; it needs to be a file in the
#     directory named by the most recent Directory request.
sub req_Questionable
{
    my ( $cmd, $data ) = @_;

    $log->debug("req_Questionable : $data");
    $state->{entries}{$state->{directory}.$data}{questionable} = 1;
}

# add \n
#     Response expected: yes. Add a file or directory. This uses any previous
#     Argument, Directory, Entry, or Modified requests, if they have been sent.
#     The last Directory sent specifies the working directory at the time of
#     the operation. To add a directory, send the directory to be added using
#     Directory and Argument requests.
sub req_add
{
    my ( $cmd, $data ) = @_;

    argsplit("add");

    my $addcount = 0;

    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        unless ( defined ( $state->{entries}{$filename}{modified_filename} ) )
        {
            print "E cvs add: nothing known about `$filename'\n";
            next;
        }
        # TODO : check we're not squashing an already existing file
        if ( defined ( $state->{entries}{$filename}{revision} ) )
        {
            print "E cvs add: `$filename' has already been entered\n";
            next;
        }

        my ( $filepart, $dirpart ) = filenamesplit($filename, 1);

        print "E cvs add: scheduling file `$filename' for addition\n";

        print "Checked-in $dirpart\n";
        print "$filename\n";
        my $kopts = kopts_from_path($filepart);
        print "/$filepart/0//$kopts/\n";

        $addcount++;
    }

    if ( $addcount == 1 )
    {
        print "E cvs add: use `cvs commit' to add this file permanently\n";
    }
    elsif ( $addcount > 1 )
    {
        print "E cvs add: use `cvs commit' to add these files permanently\n";
    }

    print "ok\n";
}

# remove \n
#     Response expected: yes. Remove a file. This uses any previous Argument,
#     Directory, Entry, or Modified requests, if they have been sent. The last
#     Directory sent specifies the working directory at the time of the
#     operation. Note that this request does not actually do anything to the
#     repository; the only effect of a successful remove request is to supply
#     the client with a new entries line containing `-' to indicate a removed
#     file. In fact, the client probably could perform this operation without
#     contacting the server, although using remove may cause the server to
#     perform a few more checks. The client sends a subsequent ci request to
#     actually record the removal in the repository.
sub req_remove
{
    my ( $cmd, $data ) = @_;

    argsplit("remove");

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    #$log->debug("add state : " . Dumper($state));

    my $rmcount = 0;

    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        if ( defined ( $state->{entries}{$filename}{unchanged} ) or defined ( $state->{entries}{$filename}{modified_filename} ) )
        {
            print "E cvs remove: file `$filename' still in working directory\n";
            next;
        }

        my $meta = $updater->getmeta($filename);
        my $wrev = revparse($filename);

        unless ( defined ( $wrev ) )
        {
            print "E cvs remove: nothing known about `$filename'\n";
            next;
        }

        if ( defined($wrev) and $wrev < 0 )
        {
            print "E cvs remove: file `$filename' already scheduled for removal\n";
            next;
        }

        unless ( $wrev == $meta->{revision} )
        {
            # TODO : not sure if the format of this message is quite correct.
            print "E cvs remove: Up to date check failed for `$filename'\n";
            next;
        }


        my ( $filepart, $dirpart ) = filenamesplit($filename, 1);

        print "E cvs remove: scheduling `$filename' for removal\n";

        print "Checked-in $dirpart\n";
        print "$filename\n";
        my $kopts = kopts_from_path($filepart);
        print "/$filepart/-1.$wrev//$kopts/\n";

        $rmcount++;
    }

    if ( $rmcount == 1 )
    {
        print "E cvs remove: use `cvs commit' to remove this file permanently\n";
    }
    elsif ( $rmcount > 1 )
    {
        print "E cvs remove: use `cvs commit' to remove these files permanently\n";
    }

    print "ok\n";
}

# Modified filename \n
#     Response expected: no. Additional data: mode, \n, file transmission. Send
#     the server a copy of one locally modified file. filename is a file within
#     the most recent directory sent with Directory; it must not contain `/'.
#     If the user is operating on only some files in a directory, only those
#     files need to be included. This can also be sent without Entry, if there
#     is no entry for the file.
sub req_Modified
{
    my ( $cmd, $data ) = @_;

    my $mode = <STDIN>;
    chomp $mode;
    my $size = <STDIN>;
    chomp $size;

    # Grab config information
    my $blocksize = 8192;
    my $bytesleft = $size;
    my $tmp;

    # Get a filehandle/name to write it to
    my ( $fh, $filename ) = tempfile( DIR => $TEMP_DIR );

    # Loop over file data writing out to temporary file.
    while ( $bytesleft )
    {
        $blocksize = $bytesleft if ( $bytesleft < $blocksize );
        read STDIN, $tmp, $blocksize;
        print $fh $tmp;
        $bytesleft -= $blocksize;
    }

    close $fh;

    # Ensure we have something sensible for the file mode
    if ( $mode =~ /u=(\w+)/ )
    {
        $mode = $1;
    } else {
        $mode = "rw";
    }

    # Save the file data in $state
    $state->{entries}{$state->{directory}.$data}{modified_filename} = $filename;
    $state->{entries}{$state->{directory}.$data}{modified_mode} = $mode;
    $state->{entries}{$state->{directory}.$data}{modified_hash} = `git-hash-object $filename`;
    $state->{entries}{$state->{directory}.$data}{modified_hash} =~ s/\s.*$//s;

    #$log->debug("req_Modified : file=$data mode=$mode size=$size");
}

# Unchanged filename \n
#     Response expected: no. Tell the server that filename has not been
#     modified in the checked out directory. The filename is a file within the
#     most recent directory sent with Directory; it must not contain `/'.
sub req_Unchanged
{
    my ( $cmd, $data ) = @_;

    $state->{entries}{$state->{directory}.$data}{unchanged} = 1;

    #$log->debug("req_Unchanged : $data");
}

# Argument text \n
#     Response expected: no. Save argument for use in a subsequent command.
#     Arguments accumulate until an argument-using command is given, at which
#     point they are forgotten.
# Argumentx text \n
#     Response expected: no. Append \n followed by text to the current argument
#     being saved.
sub req_Argument
{
    my ( $cmd, $data ) = @_;

    # Argumentx means: append to last Argument (with a newline in front)

    $log->debug("$cmd : $data");

    if ( $cmd eq 'Argumentx') {
        ${$state->{arguments}}[$#{$state->{arguments}}] .= "\n" . $data;
    } else {
        push @{$state->{arguments}}, $data;
    }
}

# expand-modules \n
#     Response expected: yes. Expand the modules which are specified in the
#     arguments. Returns the data in Module-expansion responses. Note that the
#     server can assume that this is checkout or export, not rtag or rdiff; the
#     latter do not access the working directory and thus have no need to
#     expand modules on the client side. Expand may not be the best word for
#     what this request does. It does not necessarily tell you all the files
#     contained in a module, for example. Basically it is a way of telling you
#     which working directories the server needs to know about in order to
#     handle a checkout of the specified modules. For example, suppose that the
#     server has a module defined by
#   aliasmodule -a 1dir
#     That is, one can check out aliasmodule and it will take 1dir in the
#     repository and check it out to 1dir in the working directory. Now suppose
#     the client already has this module checked out and is planning on using
#     the co request to update it. Without using expand-modules, the client
#     would have two bad choices: it could either send information about all
#     working directories under the current directory, which could be
#     unnecessarily slow, or it could be ignorant of the fact that aliasmodule
#     stands for 1dir, and neglect to send information for 1dir, which would
#     lead to incorrect operation. With expand-modules, the client would first
#     ask for the module to be expanded:
sub req_expandmodules
{
    my ( $cmd, $data ) = @_;

    argsplit();

    $log->debug("req_expandmodules : " . ( defined($data) ? $data : "[NULL]" ) );

    unless ( ref $state->{arguments} eq "ARRAY" )
    {
        print "ok\n";
        return;
    }

    foreach my $module ( @{$state->{arguments}} )
    {
        $log->debug("SEND : Module-expansion $module");
        print "Module-expansion $module\n";
    }

    print "ok\n";
    statecleanup();
}

# co \n
#     Response expected: yes. Get files from the repository. This uses any
#     previous Argument, Directory, Entry, or Modified requests, if they have
#     been sent. Arguments to this command are module names; the client cannot
#     know what directories they correspond to except by (1) just sending the
#     co request, and then seeing what directory names the server sends back in
#     its responses, and (2) the expand-modules request.
sub req_co
{
    my ( $cmd, $data ) = @_;

    argsplit("co");

    my $module = $state->{args}[0];
    my $checkout_path = $module;

    # use the user specified directory if we're given it
    $checkout_path = $state->{opt}{d} if ( exists ( $state->{opt}{d} ) );

    $log->debug("req_co : " . ( defined($data) ? $data : "[NULL]" ) );

    $log->info("Checking out module '$module' ($state->{CVSROOT}) to '$checkout_path'");

    $ENV{GIT_DIR} = $state->{CVSROOT} . "/";

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $module, $log);
    $updater->update();

    $checkout_path =~ s|/$||; # get rid of trailing slashes

    # Eclipse seems to need the Clear-sticky command
    # to prepare the 'Entries' file for the new directory.
    print "Clear-sticky $checkout_path/\n";
    print $state->{CVSROOT} . "/$module/\n";
    print "Clear-static-directory $checkout_path/\n";
    print $state->{CVSROOT} . "/$module/\n";
    print "Clear-sticky $checkout_path/\n"; # yes, twice
    print $state->{CVSROOT} . "/$module/\n";
    print "Template $checkout_path/\n";
    print $state->{CVSROOT} . "/$module/\n";
    print "0\n";

    # instruct the client that we're checking out to $checkout_path
    print "E cvs checkout: Updating $checkout_path\n";

    my %seendirs = ();
    my $lastdir ='';

    # recursive
    sub prepdir {
       my ($dir, $repodir, $remotedir, $seendirs) = @_;
       my $parent = dirname($dir);
       $dir       =~ s|/+$||;
       $repodir   =~ s|/+$||;
       $remotedir =~ s|/+$||;
       $parent    =~ s|/+$||;
       $log->debug("announcedir $dir, $repodir, $remotedir" );

       if ($parent eq '.' || $parent eq './') {
           $parent = '';
       }
       # recurse to announce unseen parents first
       if (length($parent) && !exists($seendirs->{$parent})) {
           prepdir($parent, $repodir, $remotedir, $seendirs);
       }
       # Announce that we are going to modify at the parent level
       if ($parent) {
           print "E cvs checkout: Updating $remotedir/$parent\n";
       } else {
           print "E cvs checkout: Updating $remotedir\n";
       }
       print "Clear-sticky $remotedir/$parent/\n";
       print "$repodir/$parent/\n";

       print "Clear-static-directory $remotedir/$dir/\n";
       print "$repodir/$dir/\n";
       print "Clear-sticky $remotedir/$parent/\n"; # yes, twice
       print "$repodir/$parent/\n";
       print "Template $remotedir/$dir/\n";
       print "$repodir/$dir/\n";
       print "0\n";

       $seendirs->{$dir} = 1;
    }

    foreach my $git ( @{$updater->gethead} )
    {
        # Don't want to check out deleted files
        next if ( $git->{filehash} eq "deleted" );

        ( $git->{name}, $git->{dir} ) = filenamesplit($git->{name});

       if (length($git->{dir}) && $git->{dir} ne './'
           && $git->{dir} ne $lastdir ) {
           unless (exists($seendirs{$git->{dir}})) {
               prepdir($git->{dir}, $state->{CVSROOT} . "/$module/",
                       $checkout_path, \%seendirs);
               $lastdir = $git->{dir};
               $seendirs{$git->{dir}} = 1;
           }
           print "E cvs checkout: Updating /$checkout_path/$git->{dir}\n";
       }

        # modification time of this file
        print "Mod-time $git->{modified}\n";

        # print some information to the client
        if ( defined ( $git->{dir} ) and $git->{dir} ne "./" )
        {
            print "M U $checkout_path/$git->{dir}$git->{name}\n";
        } else {
            print "M U $checkout_path/$git->{name}\n";
        }

       # instruct client we're sending a file to put in this path
       print "Created $checkout_path/" . ( defined ( $git->{dir} ) and $git->{dir} ne "./" ? $git->{dir} . "/" : "" ) . "\n";

       print $state->{CVSROOT} . "/$module/" . ( defined ( $git->{dir} ) and $git->{dir} ne "./" ? $git->{dir} . "/" : "" ) . "$git->{name}\n";

        # this is an "entries" line
        my $kopts = kopts_from_path($git->{name});
        print "/$git->{name}/1.$git->{revision}//$kopts/\n";
        # permissions
        print "u=$git->{mode},g=$git->{mode},o=$git->{mode}\n";

        # transmit file
        transmitfile($git->{filehash});
    }

    print "ok\n";

    statecleanup();
}

# update \n
#     Response expected: yes. Actually do a cvs update command. This uses any
#     previous Argument, Directory, Entry, or Modified requests, if they have
#     been sent. The last Directory sent specifies the working directory at the
#     time of the operation. The -I option is not used--files which the client
#     can decide whether to ignore are not mentioned and the client sends the
#     Questionable request for others.
sub req_update
{
    my ( $cmd, $data ) = @_;

    $log->debug("req_update : " . ( defined($data) ? $data : "[NULL]" ));

    argsplit("update");

    #
    # It may just be a client exploring the available heads/modules
    # in that case, list them as top level directories and leave it
    # at that. Eclipse uses this technique to offer you a list of
    # projects (heads in this case) to checkout.
    #
    if ($state->{module} eq '') {
        print "E cvs update: Updating .\n";
	opendir HEADS, $state->{CVSROOT} . '/refs/heads';
	while (my $head = readdir(HEADS)) {
	    if (-f $state->{CVSROOT} . '/refs/heads/' . $head) {
	        print "E cvs update: New directory `$head'\n";
	    }
	}
	closedir HEADS;
	print "ok\n";
	return 1;
    }


    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);

    $updater->update();

    argsfromdir($updater);

    #$log->debug("update state : " . Dumper($state));

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        $log->debug("Processing file $filename");

        # if we have a -C we should pretend we never saw modified stuff
        if ( exists ( $state->{opt}{C} ) )
        {
            delete $state->{entries}{$filename}{modified_hash};
            delete $state->{entries}{$filename}{modified_filename};
            $state->{entries}{$filename}{unchanged} = 1;
        }

        my $meta;
        if ( defined($state->{opt}{r}) and $state->{opt}{r} =~ /^1\.(\d+)/ )
        {
            $meta = $updater->getmeta($filename, $1);
        } else {
            $meta = $updater->getmeta($filename);
        }

	if ( ! defined $meta )
	{
	    $meta = {
	        name => $filename,
	        revision => 0,
	        filehash => 'added'
	    };
	}

        my $oldmeta = $meta;

        my $wrev = revparse($filename);

        # If the working copy is an old revision, lets get that version too for comparison.
        if ( defined($wrev) and $wrev != $meta->{revision} )
        {
            $oldmeta = $updater->getmeta($filename, $wrev);
        }

        #$log->debug("Target revision is $meta->{revision}, current working revision is $wrev");

        # Files are up to date if the working copy and repo copy have the same revision,
        # and the working copy is unmodified _and_ the user hasn't specified -C
        next if ( defined ( $wrev )
                  and defined($meta->{revision})
                  and $wrev == $meta->{revision}
                  and $state->{entries}{$filename}{unchanged}
                  and not exists ( $state->{opt}{C} ) );

        # If the working copy and repo copy have the same revision,
        # but the working copy is modified, tell the client it's modified
        if ( defined ( $wrev )
             and defined($meta->{revision})
             and $wrev == $meta->{revision}
             and defined($state->{entries}{$filename}{modified_hash})
             and not exists ( $state->{opt}{C} ) )
        {
            $log->info("Tell the client the file is modified");
            print "MT text M \n";
            print "MT fname $filename\n";
            print "MT newline\n";
            next;
        }

        if ( $meta->{filehash} eq "deleted" )
        {
            my ( $filepart, $dirpart ) = filenamesplit($filename,1);

            $log->info("Removing '$filename' from working copy (no longer in the repo)");

            print "E cvs update: `$filename' is no longer in the repository\n";
            # Don't want to actually _DO_ the update if -n specified
            unless ( $state->{globaloptions}{-n} ) {
		print "Removed $dirpart\n";
		print "$filepart\n";
	    }
        }
        elsif ( not defined ( $state->{entries}{$filename}{modified_hash} )
		or $state->{entries}{$filename}{modified_hash} eq $oldmeta->{filehash}
		or $meta->{filehash} eq 'added' )
        {
            # normal update, just send the new revision (either U=Update,
            # or A=Add, or R=Remove)
	    if ( defined($wrev) && $wrev < 0 )
	    {
	        $log->info("Tell the client the file is scheduled for removal");
		print "MT text R \n";
                print "MT fname $filename\n";
                print "MT newline\n";
		next;
	    }
	    elsif ( (!defined($wrev) || $wrev == 0) && (!defined($meta->{revision}) || $meta->{revision} == 0) )
	    {
	        $log->info("Tell the client the file is scheduled for addition");
		print "MT text A \n";
                print "MT fname $filename\n";
                print "MT newline\n";
		next;

	    }
	    else {
                $log->info("Updating '$filename' to ".$meta->{revision});
                print "MT +updated\n";
                print "MT text U \n";
                print "MT fname $filename\n";
                print "MT newline\n";
		print "MT -updated\n";
	    }

            my ( $filepart, $dirpart ) = filenamesplit($filename,1);

	    # Don't want to actually _DO_ the update if -n specified
	    unless ( $state->{globaloptions}{-n} )
	    {
		if ( defined ( $wrev ) )
		{
		    # instruct client we're sending a file to put in this path as a replacement
		    print "Update-existing $dirpart\n";
		    $log->debug("Updating existing file 'Update-existing $dirpart'");
		} else {
		    # instruct client we're sending a file to put in this path as a new file
		    print "Clear-static-directory $dirpart\n";
		    print $state->{CVSROOT} . "/$state->{module}/$dirpart\n";
		    print "Clear-sticky $dirpart\n";
		    print $state->{CVSROOT} . "/$state->{module}/$dirpart\n";

		    $log->debug("Creating new file 'Created $dirpart'");
		    print "Created $dirpart\n";
		}
		print $state->{CVSROOT} . "/$state->{module}/$filename\n";

		# this is an "entries" line
		my $kopts = kopts_from_path($filepart);
		$log->debug("/$filepart/1.$meta->{revision}//$kopts/");
		print "/$filepart/1.$meta->{revision}//$kopts/\n";

		# permissions
		$log->debug("SEND : u=$meta->{mode},g=$meta->{mode},o=$meta->{mode}");
		print "u=$meta->{mode},g=$meta->{mode},o=$meta->{mode}\n";

		# transmit file
		transmitfile($meta->{filehash});
	    }
        } else {
            $log->info("Updating '$filename'");
            my ( $filepart, $dirpart ) = filenamesplit($meta->{name},1);

            my $dir = tempdir( DIR => $TEMP_DIR, CLEANUP => 1 ) . "/";

            chdir $dir;
            my $file_local = $filepart . ".mine";
            system("ln","-s",$state->{entries}{$filename}{modified_filename}, $file_local);
            my $file_old = $filepart . "." . $oldmeta->{revision};
            transmitfile($oldmeta->{filehash}, $file_old);
            my $file_new = $filepart . "." . $meta->{revision};
            transmitfile($meta->{filehash}, $file_new);

            # we need to merge with the local changes ( M=successful merge, C=conflict merge )
            $log->info("Merging $file_local, $file_old, $file_new");
            print "M Merging differences between 1.$oldmeta->{revision} and 1.$meta->{revision} into $filename\n";

            $log->debug("Temporary directory for merge is $dir");

            my $return = system("git", "merge-file", $file_local, $file_old, $file_new);
            $return >>= 8;

            if ( $return == 0 )
            {
                $log->info("Merged successfully");
                print "M M $filename\n";
                $log->debug("Merged $dirpart");

                # Don't want to actually _DO_ the update if -n specified
                unless ( $state->{globaloptions}{-n} )
                {
                    print "Merged $dirpart\n";
                    $log->debug($state->{CVSROOT} . "/$state->{module}/$filename");
                    print $state->{CVSROOT} . "/$state->{module}/$filename\n";
                    my $kopts = kopts_from_path($filepart);
                    $log->debug("/$filepart/1.$meta->{revision}//$kopts/");
                    print "/$filepart/1.$meta->{revision}//$kopts/\n";
                }
            }
            elsif ( $return == 1 )
            {
                $log->info("Merged with conflicts");
                print "E cvs update: conflicts found in $filename\n";
                print "M C $filename\n";

                # Don't want to actually _DO_ the update if -n specified
                unless ( $state->{globaloptions}{-n} )
                {
                    print "Merged $dirpart\n";
                    print $state->{CVSROOT} . "/$state->{module}/$filename\n";
                    my $kopts = kopts_from_path($filepart);
                    print "/$filepart/1.$meta->{revision}/+/$kopts/\n";
                }
            }
            else
            {
                $log->warn("Merge failed");
                next;
            }

            # Don't want to actually _DO_ the update if -n specified
            unless ( $state->{globaloptions}{-n} )
            {
                # permissions
                $log->debug("SEND : u=$meta->{mode},g=$meta->{mode},o=$meta->{mode}");
                print "u=$meta->{mode},g=$meta->{mode},o=$meta->{mode}\n";

                # transmit file, format is single integer on a line by itself (file
                # size) followed by the file contents
                # TODO : we should copy files in blocks
                my $data = `cat $file_local`;
                $log->debug("File size : " . length($data));
                print length($data) . "\n";
                print $data;
            }

            chdir "/";
        }

    }

    print "ok\n";
}

sub req_ci
{
    my ( $cmd, $data ) = @_;

    argsplit("ci");

    #$log->debug("State : " . Dumper($state));

    $log->info("req_ci : " . ( defined($data) ? $data : "[NULL]" ));

    if ( @ARGV && $ARGV[0] eq 'pserver')
    {
        print "error 1 pserver access cannot commit\n";
        exit;
    }

    if ( -e $state->{CVSROOT} . "/index" )
    {
        $log->warn("file 'index' already exists in the git repository");
        print "error 1 Index already exists in git repo\n";
        exit;
    }

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    my $tmpdir = tempdir ( DIR => $TEMP_DIR );
    my ( undef, $file_index ) = tempfile ( DIR => $TEMP_DIR, OPEN => 0 );
    $log->info("Lockless commit start, basing commit on '$tmpdir', index file is '$file_index'");

    $ENV{GIT_DIR} = $state->{CVSROOT} . "/";
    $ENV{GIT_INDEX_FILE} = $file_index;

    # Remember where the head was at the beginning.
    my $parenthash = `git show-ref -s refs/heads/$state->{module}`;
    chomp $parenthash;
    if ($parenthash !~ /^[0-9a-f]{40}$/) {
	    print "error 1 pserver cannot find the current HEAD of module";
	    exit;
    }

    chdir $tmpdir;

    # populate the temporary index based
    system("git-read-tree", $parenthash);
    unless ($? == 0)
    {
	die "Error running git-read-tree $state->{module} $file_index $!";
    }
    $log->info("Created index '$file_index' with for head $state->{module} - exit status $?");

    my @committedfiles = ();
    my %oldmeta;

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        my $committedfile = $filename;
        $filename = filecleanup($filename);

        next unless ( exists $state->{entries}{$filename}{modified_filename} or not $state->{entries}{$filename}{unchanged} );

        my $meta = $updater->getmeta($filename);
	$oldmeta{$filename} = $meta;

        my $wrev = revparse($filename);

        my ( $filepart, $dirpart ) = filenamesplit($filename);

        # do a checkout of the file if it part of this tree
        if ($wrev) {
            system('git-checkout-index', '-f', '-u', $filename);
            unless ($? == 0) {
                die "Error running git-checkout-index -f -u $filename : $!";
            }
        }

        my $addflag = 0;
        my $rmflag = 0;
        $rmflag = 1 if ( defined($wrev) and $wrev < 0 );
        $addflag = 1 unless ( -e $filename );

        # Do up to date checking
        unless ( $addflag or $wrev == $meta->{revision} or ( $rmflag and -$wrev == $meta->{revision} ) )
        {
            # fail everything if an up to date check fails
            print "error 1 Up to date check failed for $filename\n";
            chdir "/";
            exit;
        }

        push @committedfiles, $committedfile;
        $log->info("Committing $filename");

        system("mkdir","-p",$dirpart) unless ( -d $dirpart );

        unless ( $rmflag )
        {
            $log->debug("rename $state->{entries}{$filename}{modified_filename} $filename");
            rename $state->{entries}{$filename}{modified_filename},$filename;

            # Calculate modes to remove
            my $invmode = "";
            foreach ( qw (r w x) ) { $invmode .= $_ unless ( $state->{entries}{$filename}{modified_mode} =~ /$_/ ); }

            $log->debug("chmod u+" . $state->{entries}{$filename}{modified_mode} . "-" . $invmode . " $filename");
            system("chmod","u+" .  $state->{entries}{$filename}{modified_mode} . "-" . $invmode, $filename);
        }

        if ( $rmflag )
        {
            $log->info("Removing file '$filename'");
            unlink($filename);
            system("git-update-index", "--remove", $filename);
        }
        elsif ( $addflag )
        {
            $log->info("Adding file '$filename'");
            system("git-update-index", "--add", $filename);
        } else {
            $log->info("Updating file '$filename'");
            system("git-update-index", $filename);
        }
    }

    unless ( scalar(@committedfiles) > 0 )
    {
        print "E No files to commit\n";
        print "ok\n";
        chdir "/";
        return;
    }

    my $treehash = `git-write-tree`;
    chomp $treehash;

    $log->debug("Treehash : $treehash, Parenthash : $parenthash");

    # write our commit message out if we have one ...
    my ( $msg_fh, $msg_filename ) = tempfile( DIR => $TEMP_DIR );
    print $msg_fh $state->{opt}{m};# if ( exists ( $state->{opt}{m} ) );
    print $msg_fh "\n\nvia git-CVS emulator\n";
    close $msg_fh;

    my $commithash = `git-commit-tree $treehash -p $parenthash < $msg_filename`;
    chomp($commithash);
    $log->info("Commit hash : $commithash");

    unless ( $commithash =~ /[a-zA-Z0-9]{40}/ )
    {
        $log->warn("Commit failed (Invalid commit hash)");
        print "error 1 Commit failed (unknown reason)\n";
        chdir "/";
        exit;
    }

	# Check that this is allowed, just as we would with a receive-pack
	my @cmd = ( $ENV{GIT_DIR}.'hooks/update', "refs/heads/$state->{module}",
			$parenthash, $commithash );
	if( -x $cmd[0] ) {
		unless( system( @cmd ) == 0 )
		{
			$log->warn("Commit failed (update hook declined to update ref)");
			print "error 1 Commit failed (update hook declined)\n";
			chdir "/";
			exit;
		}
	}

	if (system(qw(git update-ref -m), "cvsserver ci",
			"refs/heads/$state->{module}", $commithash, $parenthash)) {
		$log->warn("update-ref for $state->{module} failed.");
		print "error 1 Cannot commit -- update first\n";
		exit;
	}

    $updater->update();

    # foreach file specified on the command line ...
    foreach my $filename ( @committedfiles )
    {
        $filename = filecleanup($filename);

        my $meta = $updater->getmeta($filename);
	unless (defined $meta->{revision}) {
	  $meta->{revision} = 1;
	}

        my ( $filepart, $dirpart ) = filenamesplit($filename, 1);

        $log->debug("Checked-in $dirpart : $filename");

	print "M $state->{CVSROOT}/$state->{module}/$filename,v  <--  $dirpart$filepart\n";
        if ( defined $meta->{filehash} && $meta->{filehash} eq "deleted" )
        {
            print "M new revision: delete; previous revision: 1.$oldmeta{$filename}{revision}\n";
            print "Remove-entry $dirpart\n";
            print "$filename\n";
        } else {
            if ($meta->{revision} == 1) {
	        print "M initial revision: 1.1\n";
            } else {
	        print "M new revision: 1.$meta->{revision}; previous revision: 1.$oldmeta{$filename}{revision}\n";
            }
            print "Checked-in $dirpart\n";
            print "$filename\n";
            my $kopts = kopts_from_path($filepart);
            print "/$filepart/1.$meta->{revision}//$kopts/\n";
        }
    }

    chdir "/";
    print "ok\n";
}

sub req_status
{
    my ( $cmd, $data ) = @_;

    argsplit("status");

    $log->info("req_status : " . ( defined($data) ? $data : "[NULL]" ));
    #$log->debug("status state : " . Dumper($state));

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    # if no files were specified, we need to work out what files we should be providing status on ...
    argsfromdir($updater);

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        my $meta = $updater->getmeta($filename);
        my $oldmeta = $meta;

        my $wrev = revparse($filename);

        # If the working copy is an old revision, lets get that version too for comparison.
        if ( defined($wrev) and $wrev != $meta->{revision} )
        {
            $oldmeta = $updater->getmeta($filename, $wrev);
        }

        # TODO : All possible statuses aren't yet implemented
        my $status;
        # Files are up to date if the working copy and repo copy have the same revision, and the working copy is unmodified
        $status = "Up-to-date" if ( defined ( $wrev ) and defined($meta->{revision}) and $wrev == $meta->{revision}
                                    and
                                    ( ( $state->{entries}{$filename}{unchanged} and ( not defined ( $state->{entries}{$filename}{conflict} ) or $state->{entries}{$filename}{conflict} !~ /^\+=/ ) )
                                      or ( defined($state->{entries}{$filename}{modified_hash}) and $state->{entries}{$filename}{modified_hash} eq $meta->{filehash} ) )
                                   );

        # Need checkout if the working copy has an older revision than the repo copy, and the working copy is unmodified
        $status ||= "Needs Checkout" if ( defined ( $wrev ) and defined ( $meta->{revision} ) and $meta->{revision} > $wrev
                                          and
                                          ( $state->{entries}{$filename}{unchanged}
                                            or ( defined($state->{entries}{$filename}{modified_hash}) and $state->{entries}{$filename}{modified_hash} eq $oldmeta->{filehash} ) )
                                        );

        # Need checkout if it exists in the repo but doesn't have a working copy
        $status ||= "Needs Checkout" if ( not defined ( $wrev ) and defined ( $meta->{revision} ) );

        # Locally modified if working copy and repo copy have the same revision but there are local changes
        $status ||= "Locally Modified" if ( defined ( $wrev ) and defined($meta->{revision}) and $wrev == $meta->{revision} and $state->{entries}{$filename}{modified_filename} );

        # Needs Merge if working copy revision is less than repo copy and there are local changes
        $status ||= "Needs Merge" if ( defined ( $wrev ) and defined ( $meta->{revision} ) and $meta->{revision} > $wrev and $state->{entries}{$filename}{modified_filename} );

        $status ||= "Locally Added" if ( defined ( $state->{entries}{$filename}{revision} ) and not defined ( $meta->{revision} ) );
        $status ||= "Locally Removed" if ( defined ( $wrev ) and defined ( $meta->{revision} ) and -$wrev == $meta->{revision} );
        $status ||= "Unresolved Conflict" if ( defined ( $state->{entries}{$filename}{conflict} ) and $state->{entries}{$filename}{conflict} =~ /^\+=/ );
        $status ||= "File had conflicts on merge" if ( 0 );

        $status ||= "Unknown";

        print "M ===================================================================\n";
        print "M File: $filename\tStatus: $status\n";
        if ( defined($state->{entries}{$filename}{revision}) )
        {
            print "M Working revision:\t" . $state->{entries}{$filename}{revision} . "\n";
        } else {
            print "M Working revision:\tNo entry for $filename\n";
        }
        if ( defined($meta->{revision}) )
        {
            print "M Repository revision:\t1." . $meta->{revision} . "\t$state->{CVSROOT}/$state->{module}/$filename,v\n";
            print "M Sticky Tag:\t\t(none)\n";
            print "M Sticky Date:\t\t(none)\n";
            print "M Sticky Options:\t\t(none)\n";
        } else {
            print "M Repository revision:\tNo revision control file\n";
        }
        print "M\n";
    }

    print "ok\n";
}

sub req_diff
{
    my ( $cmd, $data ) = @_;

    argsplit("diff");

    $log->debug("req_diff : " . ( defined($data) ? $data : "[NULL]" ));
    #$log->debug("status state : " . Dumper($state));

    my ($revision1, $revision2);
    if ( defined ( $state->{opt}{r} ) and ref $state->{opt}{r} eq "ARRAY" )
    {
        $revision1 = $state->{opt}{r}[0];
        $revision2 = $state->{opt}{r}[1];
    } else {
        $revision1 = $state->{opt}{r};
    }

    $revision1 =~ s/^1\.// if ( defined ( $revision1 ) );
    $revision2 =~ s/^1\.// if ( defined ( $revision2 ) );

    $log->debug("Diffing revisions " . ( defined($revision1) ? $revision1 : "[NULL]" ) . " and " . ( defined($revision2) ? $revision2 : "[NULL]" ) );

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    # if no files were specified, we need to work out what files we should be providing status on ...
    argsfromdir($updater);

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        my ( $fh, $file1, $file2, $meta1, $meta2, $filediff );

        my $wrev = revparse($filename);

        # We need _something_ to diff against
        next unless ( defined ( $wrev ) );

        # if we have a -r switch, use it
        if ( defined ( $revision1 ) )
        {
            ( undef, $file1 ) = tempfile( DIR => $TEMP_DIR, OPEN => 0 );
            $meta1 = $updater->getmeta($filename, $revision1);
            unless ( defined ( $meta1 ) and $meta1->{filehash} ne "deleted" )
            {
                print "E File $filename at revision 1.$revision1 doesn't exist\n";
                next;
            }
            transmitfile($meta1->{filehash}, $file1);
        }
        # otherwise we just use the working copy revision
        else
        {
            ( undef, $file1 ) = tempfile( DIR => $TEMP_DIR, OPEN => 0 );
            $meta1 = $updater->getmeta($filename, $wrev);
            transmitfile($meta1->{filehash}, $file1);
        }

        # if we have a second -r switch, use it too
        if ( defined ( $revision2 ) )
        {
            ( undef, $file2 ) = tempfile( DIR => $TEMP_DIR, OPEN => 0 );
            $meta2 = $updater->getmeta($filename, $revision2);

            unless ( defined ( $meta2 ) and $meta2->{filehash} ne "deleted" )
            {
                print "E File $filename at revision 1.$revision2 doesn't exist\n";
                next;
            }

            transmitfile($meta2->{filehash}, $file2);
        }
        # otherwise we just use the working copy
        else
        {
            $file2 = $state->{entries}{$filename}{modified_filename};
        }

        # if we have been given -r, and we don't have a $file2 yet, lets get one
        if ( defined ( $revision1 ) and not defined ( $file2 ) )
        {
            ( undef, $file2 ) = tempfile( DIR => $TEMP_DIR, OPEN => 0 );
            $meta2 = $updater->getmeta($filename, $wrev);
            transmitfile($meta2->{filehash}, $file2);
        }

        # We need to have retrieved something useful
        next unless ( defined ( $meta1 ) );

        # Files to date if the working copy and repo copy have the same revision, and the working copy is unmodified
        next if ( not defined ( $meta2 ) and $wrev == $meta1->{revision}
                  and
                   ( ( $state->{entries}{$filename}{unchanged} and ( not defined ( $state->{entries}{$filename}{conflict} ) or $state->{entries}{$filename}{conflict} !~ /^\+=/ ) )
                     or ( defined($state->{entries}{$filename}{modified_hash}) and $state->{entries}{$filename}{modified_hash} eq $meta1->{filehash} ) )
                  );

        # Apparently we only show diffs for locally modified files
        next unless ( defined($meta2) or defined ( $state->{entries}{$filename}{modified_filename} ) );

        print "M Index: $filename\n";
        print "M ===================================================================\n";
        print "M RCS file: $state->{CVSROOT}/$state->{module}/$filename,v\n";
        print "M retrieving revision 1.$meta1->{revision}\n" if ( defined ( $meta1 ) );
        print "M retrieving revision 1.$meta2->{revision}\n" if ( defined ( $meta2 ) );
        print "M diff ";
        foreach my $opt ( keys %{$state->{opt}} )
        {
            if ( ref $state->{opt}{$opt} eq "ARRAY" )
            {
                foreach my $value ( @{$state->{opt}{$opt}} )
                {
                    print "-$opt $value ";
                }
            } else {
                print "-$opt ";
                print "$state->{opt}{$opt} " if ( defined ( $state->{opt}{$opt} ) );
            }
        }
        print "$filename\n";

        $log->info("Diffing $filename -r $meta1->{revision} -r " . ( $meta2->{revision} or "workingcopy" ));

        ( $fh, $filediff ) = tempfile ( DIR => $TEMP_DIR );

        if ( exists $state->{opt}{u} )
        {
            system("diff -u -L '$filename revision 1.$meta1->{revision}' -L '$filename " . ( defined($meta2->{revision}) ? "revision 1.$meta2->{revision}" : "working copy" ) . "' $file1 $file2 > $filediff");
        } else {
            system("diff $file1 $file2 > $filediff");
        }

        while ( <$fh> )
        {
            print "M $_";
        }
        close $fh;
    }

    print "ok\n";
}

sub req_log
{
    my ( $cmd, $data ) = @_;

    argsplit("log");

    $log->debug("req_log : " . ( defined($data) ? $data : "[NULL]" ));
    #$log->debug("log state : " . Dumper($state));

    my ( $minrev, $maxrev );
    if ( defined ( $state->{opt}{r} ) and $state->{opt}{r} =~ /([\d.]+)?(::?)([\d.]+)?/ )
    {
        my $control = $2;
        $minrev = $1;
        $maxrev = $3;
        $minrev =~ s/^1\.// if ( defined ( $minrev ) );
        $maxrev =~ s/^1\.// if ( defined ( $maxrev ) );
        $minrev++ if ( defined($minrev) and $control eq "::" );
    }

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    # if no files were specified, we need to work out what files we should be providing status on ...
    argsfromdir($updater);

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        my $headmeta = $updater->getmeta($filename);

        my $revisions = $updater->getlog($filename);
        my $totalrevisions = scalar(@$revisions);

        if ( defined ( $minrev ) )
        {
            $log->debug("Removing revisions less than $minrev");
            while ( scalar(@$revisions) > 0 and $revisions->[-1]{revision} < $minrev )
            {
                pop @$revisions;
            }
        }
        if ( defined ( $maxrev ) )
        {
            $log->debug("Removing revisions greater than $maxrev");
            while ( scalar(@$revisions) > 0 and $revisions->[0]{revision} > $maxrev )
            {
                shift @$revisions;
            }
        }

        next unless ( scalar(@$revisions) );

        print "M \n";
        print "M RCS file: $state->{CVSROOT}/$state->{module}/$filename,v\n";
        print "M Working file: $filename\n";
        print "M head: 1.$headmeta->{revision}\n";
        print "M branch:\n";
        print "M locks: strict\n";
        print "M access list:\n";
        print "M symbolic names:\n";
        print "M keyword substitution: kv\n";
        print "M total revisions: $totalrevisions;\tselected revisions: " . scalar(@$revisions) . "\n";
        print "M description:\n";

        foreach my $revision ( @$revisions )
        {
            print "M ----------------------------\n";
            print "M revision 1.$revision->{revision}\n";
            # reformat the date for log output
            $revision->{modified} = sprintf('%04d/%02d/%02d %s', $3, $DATE_LIST->{$2}, $1, $4 ) if ( $revision->{modified} =~ /(\d+)\s+(\w+)\s+(\d+)\s+(\S+)/ and defined($DATE_LIST->{$2}) );
            $revision->{author} =~ s/\s+.*//;
            $revision->{author} =~ s/^(.{8}).*/$1/;
            print "M date: $revision->{modified};  author: $revision->{author};  state: " . ( $revision->{filehash} eq "deleted" ? "dead" : "Exp" ) . ";  lines: +2 -3\n";
            my $commitmessage = $updater->commitmessage($revision->{commithash});
            $commitmessage =~ s/^/M /mg;
            print $commitmessage . "\n";
        }
        print "M =============================================================================\n";
    }

    print "ok\n";
}

sub req_annotate
{
    my ( $cmd, $data ) = @_;

    argsplit("annotate");

    $log->info("req_annotate : " . ( defined($data) ? $data : "[NULL]" ));
    #$log->debug("status state : " . Dumper($state));

    # Grab a handle to the SQLite db and do any necessary updates
    my $updater = GITCVS::updater->new($state->{CVSROOT}, $state->{module}, $log);
    $updater->update();

    # if no files were specified, we need to work out what files we should be providing annotate on ...
    argsfromdir($updater);

    # we'll need a temporary checkout dir
    my $tmpdir = tempdir ( DIR => $TEMP_DIR );
    my ( undef, $file_index ) = tempfile ( DIR => $TEMP_DIR, OPEN => 0 );
    $log->info("Temp checkoutdir creation successful, basing annotate session work on '$tmpdir', index file is '$file_index'");

    $ENV{GIT_DIR} = $state->{CVSROOT} . "/";
    $ENV{GIT_INDEX_FILE} = $file_index;

    chdir $tmpdir;

    # foreach file specified on the command line ...
    foreach my $filename ( @{$state->{args}} )
    {
        $filename = filecleanup($filename);

        my $meta = $updater->getmeta($filename);

        next unless ( $meta->{revision} );

	# get all the commits that this file was in
	# in dense format -- aka skip dead revisions
        my $revisions   = $updater->gethistorydense($filename);
	my $lastseenin  = $revisions->[0][2];

	# populate the temporary index based on the latest commit were we saw
	# the file -- but do it cheaply without checking out any files
	# TODO: if we got a revision from the client, use that instead
	# to look up the commithash in sqlite (still good to default to
	# the current head as we do now)
	system("git-read-tree", $lastseenin);
	unless ($? == 0)
	{
	    die "Error running git-read-tree $lastseenin $file_index $!";
	}
	$log->info("Created index '$file_index' with commit $lastseenin - exit status $?");

        # do a checkout of the file
        system('git-checkout-index', '-f', '-u', $filename);
        unless ($? == 0) {
            die "Error running git-checkout-index -f -u $filename : $!";
        }

        $log->info("Annotate $filename");

        # Prepare a file with the commits from the linearized
        # history that annotate should know about. This prevents
        # git-jsannotate telling us about commits we are hiding
        # from the client.

        open(ANNOTATEHINTS, ">$tmpdir/.annotate_hints") or die "Error opening > $tmpdir/.annotate_hints $!";
        for (my $i=0; $i < @$revisions; $i++)
        {
            print ANNOTATEHINTS $revisions->[$i][2];
            if ($i+1 < @$revisions) { # have we got a parent?
                print ANNOTATEHINTS ' ' . $revisions->[$i+1][2];
            }
            print ANNOTATEHINTS "\n";
        }

        print ANNOTATEHINTS "\n";
        close ANNOTATEHINTS;

        my $annotatecmd = 'git-annotate';
        open(ANNOTATE, "-|", $annotatecmd, '-l', '-S', "$tmpdir/.annotate_hints", $filename)
	    or die "Error invoking $annotatecmd -l -S $tmpdir/.annotate_hints $filename : $!";
        my $metadata = {};
        print "E Annotations for $filename\n";
        print "E ***************\n";
        while ( <ANNOTATE> )
        {
            if (m/^([a-zA-Z0-9]{40})\t\([^\)]*\)(.*)$/i)
            {
                my $commithash = $1;
                my $data = $2;
                unless ( defined ( $metadata->{$commithash} ) )
                {
                    $metadata->{$commithash} = $updater->getmeta($filename, $commithash);
                    $metadata->{$commithash}{author} =~ s/\s+.*//;
                    $metadata->{$commithash}{author} =~ s/^(.{8}).*/$1/;
                    $metadata->{$commithash}{modified} = sprintf("%02d-%s-%02d", $1, $2, $3) if ( $metadata->{$commithash}{modified} =~ /^(\d+)\s(\w+)\s\d\d(\d\d)/ );
                }
                printf("M 1.%-5d      (%-8s %10s): %s\n",
                    $metadata->{$commithash}{revision},
                    $metadata->{$commithash}{author},
                    $metadata->{$commithash}{modified},
                    $data
                );
            } else {
                $log->warn("Error in annotate output! LINE: $_");
                print "E Annotate error \n";
                next;
            }
        }
        close ANNOTATE;
    }

    # done; get out of the tempdir
    chdir "/";

    print "ok\n";

}

# This method takes the state->{arguments} array and produces two new arrays.
# The first is $state->{args} which is everything before the '--' argument, and
# the second is $state->{files} which is everything after it.
sub argsplit
{
    return unless( defined($state->{arguments}) and ref $state->{arguments} eq "ARRAY" );

    my $type = shift;

    $state->{args} = [];
    $state->{files} = [];
    $state->{opt} = {};

    if ( defined($type) )
    {
        my $opt = {};
        $opt = { A => 0, N => 0, P => 0, R => 0, c => 0, f => 0, l => 0, n => 0, p => 0, s => 0, r => 1, D => 1, d => 1, k => 1, j => 1, } if ( $type eq "co" );
        $opt = { v => 0, l => 0, R => 0 } if ( $type eq "status" );
        $opt = { A => 0, P => 0, C => 0, d => 0, f => 0, l => 0, R => 0, p => 0, k => 1, r => 1, D => 1, j => 1, I => 1, W => 1 } if ( $type eq "update" );
        $opt = { l => 0, R => 0, k => 1, D => 1, D => 1, r => 2 } if ( $type eq "diff" );
        $opt = { c => 0, R => 0, l => 0, f => 0, F => 1, m => 1, r => 1 } if ( $type eq "ci" );
        $opt = { k => 1, m => 1 } if ( $type eq "add" );
        $opt = { f => 0, l => 0, R => 0 } if ( $type eq "remove" );
        $opt = { l => 0, b => 0, h => 0, R => 0, t => 0, N => 0, S => 0, r => 1, d => 1, s => 1, w => 1 } if ( $type eq "log" );


        while ( scalar ( @{$state->{arguments}} ) > 0 )
        {
            my $arg = shift @{$state->{arguments}};

            next if ( $arg eq "--" );
            next unless ( $arg =~ /\S/ );

            # if the argument looks like a switch
            if ( $arg =~ /^-(\w)(.*)/ )
            {
                # if it's a switch that takes an argument
                if ( $opt->{$1} )
                {
                    # If this switch has already been provided
                    if ( $opt->{$1} > 1 and exists ( $state->{opt}{$1} ) )
                    {
                        $state->{opt}{$1} = [ $state->{opt}{$1} ];
                        if ( length($2) > 0 )
                        {
                            push @{$state->{opt}{$1}},$2;
                        } else {
                            push @{$state->{opt}{$1}}, shift @{$state->{arguments}};
                        }
                    } else {
                        # if there's extra data in the arg, use that as the argument for the switch
                        if ( length($2) > 0 )
                        {
                            $state->{opt}{$1} = $2;
                        } else {
                            $state->{opt}{$1} = shift @{$state->{arguments}};
                        }
                    }
                } else {
                    $state->{opt}{$1} = undef;
                }
            }
            else
            {
                push @{$state->{args}}, $arg;
            }
        }
    }
    else
    {
        my $mode = 0;

        foreach my $value ( @{$state->{arguments}} )
        {
            if ( $value eq "--" )
            {
                $mode++;
                next;
            }
            push @{$state->{args}}, $value if ( $mode == 0 );
            push @{$state->{files}}, $value if ( $mode == 1 );
        }
    }
}

# This method uses $state->{directory} to populate $state->{args} with a list of filenames
sub argsfromdir
{
    my $updater = shift;

    $state->{args} = [] if ( scalar(@{$state->{args}}) == 1 and $state->{args}[0] eq "." );

    return if ( scalar ( @{$state->{args}} ) > 1 );

    my @gethead = @{$updater->gethead};

    # push added files
    foreach my $file (keys %{$state->{entries}}) {
	if ( exists $state->{entries}{$file}{revision} &&
		$state->{entries}{$file}{revision} == 0 )
	{
	    push @gethead, { name => $file, filehash => 'added' };
	}
    }

    if ( scalar(@{$state->{args}}) == 1 )
    {
        my $arg = $state->{args}[0];
        $arg .= $state->{prependdir} if ( defined ( $state->{prependdir} ) );

        $log->info("Only one arg specified, checking for directory expansion on '$arg'");

        foreach my $file ( @gethead )
        {
            next if ( $file->{filehash} eq "deleted" and not defined ( $state->{entries}{$file->{name}} ) );
            next unless ( $file->{name} =~ /^$arg\// or $file->{name} eq $arg  );
            push @{$state->{args}}, $file->{name};
        }

        shift @{$state->{args}} if ( scalar(@{$state->{args}}) > 1 );
    } else {
        $log->info("Only one arg specified, populating file list automatically");

        $state->{args} = [];

        foreach my $file ( @gethead )
        {
            next if ( $file->{filehash} eq "deleted" and not defined ( $state->{entries}{$file->{name}} ) );
            next unless ( $file->{name} =~ s/^$state->{prependdir}// );
            push @{$state->{args}}, $file->{name};
        }
    }
}

# This method cleans up the $state variable after a command that uses arguments has run
sub statecleanup
{
    $state->{files} = [];
    $state->{args} = [];
    $state->{arguments} = [];
    $state->{entries} = {};
}

sub revparse
{
    my $filename = shift;

    return un