f1678851de954dd93ab0e2fc7912813ad5f09960
   1#
   2# Example implementation for the Git filter protocol version 2
   3# See Documentation/gitattributes.txt, section "Filter Protocol"
   4#
   5# The first argument defines a debug log file that the script write to.
   6# All remaining arguments define a list of supported protocol
   7# capabilities ("clean", "smudge", etc).
   8#
   9# This implementation supports special test cases:
  10# (1) If data with the pathname "clean-write-fail.r" is processed with
  11#     a "clean" operation then the write operation will die.
  12# (2) If data with the pathname "smudge-write-fail.r" is processed with
  13#     a "smudge" operation then the write operation will die.
  14# (3) If data with the pathname "error.r" is processed with any
  15#     operation then the filter signals that it cannot or does not want
  16#     to process the file.
  17# (4) If data with the pathname "abort.r" is processed with any
  18#     operation then the filter signals that it cannot or does not want
  19#     to process the file and any file after that is processed with the
  20#     same command.
  21# (5) If data with a pathname that is a key in the DELAY hash is
  22#     requested (e.g. "test-delay10.a") then the filter responds with
  23#     a "delay" status and sets the "requested" field in the DELAY hash.
  24#     The filter will signal the availability of this object after
  25#     "count" (field in DELAY hash) "list_available_blobs" commands.
  26# (6) If data with the pathname "missing-delay.a" is processed that the
  27#     filter will drop the path from the "list_available_blobs" response.
  28# (7) If data with the pathname "invalid-delay.a" is processed that the
  29#     filter will add the path "unfiltered" which was not delayed before
  30#     to the "list_available_blobs" response.
  31#
  32
  33use 5.008;
  34use lib (split(/:/, $ENV{GITPERLLIB}));
  35use strict;
  36use warnings;
  37use IO::File;
  38use Git::Packet;
  39
  40my $MAX_PACKET_CONTENT_SIZE = 65516;
  41my $log_file                = shift @ARGV;
  42my @capabilities            = @ARGV;
  43
  44open my $debug, ">>", $log_file or die "cannot open log file: $!";
  45
  46my %DELAY = (
  47        'test-delay10.a' => { "requested" => 0, "count" => 1 },
  48        'test-delay11.a' => { "requested" => 0, "count" => 1 },
  49        'test-delay20.a' => { "requested" => 0, "count" => 2 },
  50        'test-delay10.b' => { "requested" => 0, "count" => 1 },
  51        'missing-delay.a' => { "requested" => 0, "count" => 1 },
  52        'invalid-delay.a' => { "requested" => 0, "count" => 1 },
  53);
  54
  55sub rot13 {
  56        my $str = shift;
  57        $str =~ y/A-Za-z/N-ZA-Mn-za-m/;
  58        return $str;
  59}
  60
  61print $debug "START\n";
  62$debug->flush();
  63
  64packet_initialize("git-filter", 2);
  65
  66my %remote_caps = packet_read_and_check_capabilities("clean", "smudge", "delay");
  67packet_check_and_write_capabilities(\%remote_caps, @capabilities);
  68
  69print $debug "init handshake complete\n";
  70$debug->flush();
  71
  72while (1) {
  73        my ( $res, $command ) = packet_key_val_read("command");
  74        if ( $res == -1 ) {
  75                print $debug "STOP\n";
  76                exit();
  77        }
  78        print $debug "IN: $command";
  79        $debug->flush();
  80
  81        if ( $command eq "list_available_blobs" ) {
  82                # Flush
  83                packet_compare_lists([1, ""], packet_bin_read()) ||
  84                        die "bad list_available_blobs end";
  85
  86                foreach my $pathname ( sort keys %DELAY ) {
  87                        if ( $DELAY{$pathname}{"requested"} >= 1 ) {
  88                                $DELAY{$pathname}{"count"} = $DELAY{$pathname}{"count"} - 1;
  89                                if ( $pathname eq "invalid-delay.a" ) {
  90                                        # Send Git a pathname that was not delayed earlier
  91                                        packet_txt_write("pathname=unfiltered");
  92                                }
  93                                if ( $pathname eq "missing-delay.a" ) {
  94                                        # Do not signal Git that this file is available
  95                                } elsif ( $DELAY{$pathname}{"count"} == 0 ) {
  96                                        print $debug " $pathname";
  97                                        packet_txt_write("pathname=$pathname");
  98                                }
  99                        }
 100                }
 101
 102                packet_flush();
 103
 104                print $debug " [OK]\n";
 105                $debug->flush();
 106                packet_txt_write("status=success");
 107                packet_flush();
 108        } else {
 109                my ( $res, $pathname ) = packet_key_val_read("pathname");
 110                if ( $res == -1 ) {
 111                        die "unexpected EOF while expecting pathname";
 112                }
 113                print $debug " $pathname";
 114                $debug->flush();
 115
 116                # Read until flush
 117                my ( $done, $buffer ) = packet_txt_read();
 118                while ( $buffer ne '' ) {
 119                        if ( $buffer eq "can-delay=1" ) {
 120                                if ( exists $DELAY{$pathname} and $DELAY{$pathname}{"requested"} == 0 ) {
 121                                        $DELAY{$pathname}{"requested"} = 1;
 122                                }
 123                        } else {
 124                                die "Unknown message '$buffer'";
 125                        }
 126
 127                        ( $done, $buffer ) = packet_txt_read();
 128                }
 129                if ( $done == -1 ) {
 130                        die "unexpected EOF after pathname '$pathname'";
 131                }
 132
 133                my $input = "";
 134                {
 135                        binmode(STDIN);
 136                        my $buffer;
 137                        my $done = 0;
 138                        while ( !$done ) {
 139                                ( $done, $buffer ) = packet_bin_read();
 140                                $input .= $buffer;
 141                        }
 142                        if ( $done == -1 ) {
 143                                die "unexpected EOF while reading input for '$pathname'";
 144                        }                       
 145                        print $debug " " . length($input) . " [OK] -- ";
 146                        $debug->flush();
 147                }
 148
 149                my $output;
 150                if ( exists $DELAY{$pathname} and exists $DELAY{$pathname}{"output"} ) {
 151                        $output = $DELAY{$pathname}{"output"}
 152                } elsif ( $pathname eq "error.r" or $pathname eq "abort.r" ) {
 153                        $output = "";
 154                } elsif ( $command eq "clean" and grep( /^clean$/, @capabilities ) ) {
 155                        $output = rot13($input);
 156                } elsif ( $command eq "smudge" and grep( /^smudge$/, @capabilities ) ) {
 157                        $output = rot13($input);
 158                } else {
 159                        die "bad command '$command'";
 160                }
 161
 162                if ( $pathname eq "error.r" ) {
 163                        print $debug "[ERROR]\n";
 164                        $debug->flush();
 165                        packet_txt_write("status=error");
 166                        packet_flush();
 167                } elsif ( $pathname eq "abort.r" ) {
 168                        print $debug "[ABORT]\n";
 169                        $debug->flush();
 170                        packet_txt_write("status=abort");
 171                        packet_flush();
 172                } elsif ( $command eq "smudge" and
 173                        exists $DELAY{$pathname} and
 174                        $DELAY{$pathname}{"requested"} == 1 ) {
 175                        print $debug "[DELAYED]\n";
 176                        $debug->flush();
 177                        packet_txt_write("status=delayed");
 178                        packet_flush();
 179                        $DELAY{$pathname}{"requested"} = 2;
 180                        $DELAY{$pathname}{"output"} = $output;
 181                } else {
 182                        packet_txt_write("status=success");
 183                        packet_flush();
 184
 185                        if ( $pathname eq "${command}-write-fail.r" ) {
 186                                print $debug "[WRITE FAIL]\n";
 187                                $debug->flush();
 188                                die "${command} write error";
 189                        }
 190
 191                        print $debug "OUT: " . length($output) . " ";
 192                        $debug->flush();
 193
 194                        while ( length($output) > 0 ) {
 195                                my $packet = substr( $output, 0, $MAX_PACKET_CONTENT_SIZE );
 196                                packet_bin_write($packet);
 197                                # dots represent the number of packets
 198                                print $debug ".";
 199                                if ( length($output) > $MAX_PACKET_CONTENT_SIZE ) {
 200                                        $output = substr( $output, $MAX_PACKET_CONTENT_SIZE );
 201                                } else {
 202                                        $output = "";
 203                                }
 204                        }
 205                        packet_flush();
 206                        print $debug " [OK]\n";
 207                        $debug->flush();
 208                        packet_flush();
 209                }
 210        }
 211}