taskd/taskd.pl

   1 #!/usr/bin/perl
   2 #
   3 # taskd - Clone repositories on request
   4 #
   5 # taskd is Girocco mirroring servant; it processes requests for clones
   6 # of given URLs received over its socket.
   7 #
   8 # When a request is received, new process is spawned that sets up
   9 # the repository and reports further progress
  10 # to .clonelog within the repository. In case the clone fails,
  11 # .clone_failed is touched and .clone_in_progress is removed.
  12
  13 # Protocol:
  14 # Alice sets up repository and touches .cloning
  15 # Alice opens connection to Bob
  16 # Alice sends project name through the connection
  17 # Bob opens the repository and sends back 0 if ok, error code otherwise
  18 # Bob closes connection
  19 # Alice polls .clonelog in case of 0.
  20 # If Alice reads "@OVER@" from .clonelog, it stops polling.
  21
  22 # Based on perlipc example.
  23
  24 use strict;
  25 use warnings;
  26
  27 use Girocco::Config;
  28 use Girocco::Project;
  29 use Socket;
  30
  31 $| = 1;
  32
  33 sub logmsg { print '['.(scalar localtime)."] $0 $$: @_\n" }
  34
  35 my $NAME = $Girocco::Config::chroot.'/etc/taskd.socket';
  36 my $uaddr = sockaddr_un($NAME);
  37
  38 socket(Server, PF_UNIX, SOCK_STREAM, 0) or die "socket: $!";
  39 unlink($NAME);
  40 bind(Server, $uaddr) or die "bind: $!";
  41 listen(Server, SOMAXCONN) or die "listen: $!";
  42 if ($Girocco::Config::owning_group) {
  43         chmod 0664, $NAME or die "chmod: $!";
  44         my $gid = scalar(getgrnam($Girocco::Config::owning_group));
  45         chown(-1, $gid, $NAME) or die "chgrp $gid: $!";
  46 } else {
  47         chmod 0666, $NAME or die "chmod: $!";
  48 }
  49
  50
  51 use POSIX ":sys_wait_h";
  52 sub REAPER {
  53         my $child;
  54         my $waitedpid;
  55         while (($waitedpid = waitpid(-1, WNOHANG)) > 0) {
  56                 logmsg "reaped $waitedpid" . ($? ? " with exit $?" : '');
  57         }
  58         $SIG{CHLD} = \&REAPER;  # loathe sysV
  59 }
  60
  61 $SIG{CHLD} = \&REAPER;  # Apollo 440
  62
  63 sub spawn {
  64         my $coderef = shift;
  65
  66         my $pid = fork;
  67         if (not defined $pid) {
  68                 logmsg "cannot fork: $!";
  69                 return;
  70         } elsif ($pid) {
  71                 logmsg "begat $pid";
  72                 return; # I'm the parent
  73         }
  74
  75         open STDIN, "<&Client" or die "can't dup client to stdin";
  76         open STDOUT, ">&Client" or die "can't dup client to stdout";
  77         exit &$coderef();
  78 }
  79
  80 sub clone {
  81         my ($name) = @_;
  82         Girocco::Project::does_exist($name) or die "won't clone non-existing project $name";
  83         print STDERR "cloning $name\n";
  84         open STDOUT, ">".$Girocco::Config::reporoot."/".$name.".git/.clonelog" or die "cannot open clonelog: $!";
  85         open STDERR, ">&STDOUT";
  86         open STDIN, "</dev/null";
  87         exec $Girocco::Config::basedir.'/taskd/clone.sh', "$name.git" or die "exec failed: $!";
  88 }
  89
  90 while (1) {
  91         unless (accept(Client, Server)) {
  92                 logmsg "accept failed: $!";
  93                 next;
  94         }
  95         logmsg "connection on $NAME";
  96         spawn sub {
  97                 my $inp = <>;
  98                 chomp $inp;
  99                 my ($cmd, $arg) = $inp =~ /^([a-zA-Z0-9-]+)\s+(.*)$/;
 100                 if ($cmd eq 'clone') {
 101                         clone($arg);
 102                 } else {
 103                         die "unknown command: $cmd";
 104                 }
 105         };
 106         close Client;
 107         sleep 1;
 108 }