#
# usages:
# .../dgit-repos-push-receiver SUITES KEYRING-AUTH-SPEC DGIT-REPOS-DIR --ssh
-# .../dgit-repos-push-receiver SUITES KEYRING-AUTH-SPEC DGIT-REPOS-DIR PACKAGE
# internal usage:
# .../dgit-repos-push-receiver --pre-receive-hook PACKAGE
#
# - make a hardlink clone of the destination repo
# - provide the destination with a stunt pre-receive hook
# - run actual git-receive-pack with that new destination
-# as a result of this the stunt pre-receive hook runs; it does this
+# as a result of this the stunt pre-receive hook runs; it does this:
# + understand what refs we are allegedly updating and
# check some correspondences:
# * we are updating only refs/tags/debian/* and refs/dgit/*
# * and only one of each
# * and the tag does not already exist
# and
-# * recovering the suite name from the destination refs/dgit/ ref
+# * recover the suite name from the destination refs/dgit/ ref
# + disassemble the signed tag into its various fields and signature
# including:
# * parsing the first line of the tag message to recover
# - we use the prospective new destination repo instead of the
# actual new destination repo (since the latter doesn't exist)
# - we set up a post-receive hook as well, which
-# + checks that exactly two refs were updated
# + touches a stamp file
-# - after git-receive-pack exits, we rename the prospective
-# destination repo into place
+# - after git-receive-pack exits, we
+# + check that the prospective repo contains a tag and head
+# + rename the prospective destination repo into place
#
# Cleanup strategy:
# - We are crash-only
use POSIX;
use Fcntl qw(:flock);
+use File::Path qw(rmtree);
our $package_re = '[0-9a-z][-+.0-9a-z]+';
+our $func;
our $dgitrepos;
our $pkg;
+our $suitesfile;
+our $realdestrepo;
our $destrepo;
our $workrepo;
our @keyrings;
+our @lockfhs;
+
+#----- utilities -----
sub acquirelock ($$) {
my ($lock, $must) = @_;
+ my $fh;
for (;;) {
- my $fh = new IO::File, ">", $lock or die "open $lock: $!";
+ close $fh if $fh;
+ $fh = new IO::File, ">", $lock or die "open $lock: $!";
my $ok = flock $fh, $must ? LOCK_EX : (LOCK_EX|LOCK_NB);
if (!$ok) {
- return unless $must;
+ return undef unless $must;
die "flock $lock: $!";
}
if (!stat $lock) {
my $want = (stat _)[1];
stat $fh or die $!;
my $got = (stat _)[1];
- return $fh if $got == $want;
+ last if $got == $want;
+ }
+ return $fh;
+}
+
+sub acquiretree ($$) {
+ my ($tree, $must) = @_;
+ my $fh = acquirelock("$tree.lock", $must);
+ if ($fh) {
+ push @lockfhs, $fh;
+ rmtree $tree;
}
+ return $fh;
+}
+
+sub reject ($) {
+ die "dgit-repos-server: reject: $_[0]\n";
+}
+
+#----- git-receive-pack -----
+
+sub fixmissing__git_receive_pack () {
+ $destrepo = "$dgitrepos/_tmp/${pkg}_prospective";
+ acquiretree($destrepo, 1);
+ my $r = system qw(cp -a --), "$dgitrepos/_template", "$destrepo";
+ !$r or die "create new repo failed failed: $r $!";
}
sub makeworkingclone () {
$workrepo = "$dgitrepos/_tmp/${pkg}_incoming$$";
- my $lock = "$workrepo.lock";
- my $lockfh = acquirelock($lock, 1);
- if (!stat $destrepo) {
- $! == ENOENT or die "stat dest repo $destrepo: $!";
- mkdir $workrepo or die "create work repo $workrepo: $!";
- runcmd qw(git init --bare), $workrepo;
- } else {
- runcmd qw(git clone -l -q --mirror), $destrepo, $workrepo;
- }
+ acquiretree($workrepo, 1);
+ runcmd qw(git clone -l -q --mirror), $destrepo, $workrepo;
}
sub setupstunthook () {
$ENV{'DGIT_RPR_DEST'}= $destrepo;
}
+sub maybeinstallprospective () {
+ return if $destrepo eq $realdestrepo;
+
+ my $child = open SR, "-|";
+ defined $child or die $!;
+ if (!$child) {
+ chdir $destrepo or die $!;
+ exec qw(git show-ref);
+ die $!;
+ }
+ my %got = qw(tag 0 head 0);
+ while (<SR>) {
+ chomp or die;
+ s/^\S*[1-9a-f]\S* (\S+)$/$1/ or die;
+ my $wh =
+ m{^refs/tags/} ? 'tag' :
+ m{^refs/dgit/} ? 'head' :
+ die;
+ die if $got{$wh}++;
+ }
+ die if grep { !$_ } values %got;
+ $!=0; $?=0; close SR or die "$? $!";
+
+ rename $destrepo, $realdestrepo or die $!;
+ remove "$destrepo.lock" or die $!;
+}
+
+sub main__git_receive_pack () {
+ makeworkingclone();
+ setupstunthook();
+ runcmd qw(git receive-pack), $destdir;
+ maybeinstallprospective();
+}
+
#----- stunt post-receive hook -----
our ($tagname, $tagval, $suite, $oldcommit, $commit);
reject "key not found in keyrings";
}
+sub checksuite () {
+ open SUITES, "<", $suitesfile or die $!;
+ while (<SUITES>) {
+ chomp;
+ next unless m/\S/;
+ next if m/^\#/;
+ s/\s+$//;
+ return if $_ eq $suite;
+ }
+ die $! if SUITES->error;
+ reject "unknown suite";
+}
+
sub checks () {
-fixme check the suite against the approved list
+ checksuite();
tagh1('type') eq 'commit' or die;
tagh1('object') eq $commit or die;
tagh1('tag') eq $tagname or die;
#----- arg parsing and main program -----
-sub parseargs () {
+sub argval () {
+ die unless @ARGV;
+ my $v = shift @ARGV;
+ die if $v =~ m/^-/;
+ return $v;
+}
+
+sub parseargsdispatch () {
die unless @ARGV;
if ($ARGV[0] eq '--pre-receive-hook') {
shift @ARGV;
@ARGV == 1 or die;
$pkg = shift @ARGV;
+ defined($suitesfile = $ENV{'DGIT_RPR_SUITES'}) or die;
defined($workrepo = $ENV{'DGIT_RPR_WORK'}) or die;
defined($destrepo = $ENV{'DGIT_RPR_DEST'}) or die;
defined($keyrings = $ENV{'DGIT_RPR_KEYRINGS'}) or die $!;
exit 0;
}
- die unless @ARGV>=3;
-
- die if $ARGV[0] =~ m/^-/;
- $suitesfile = shift @ARGV;
-
- die if $ARGV[0] =~ m/^-/;
- $ENV{'DGIT_RPR_KEYRINGS'} = shift @ARGV;
-
- die if $ARGV[0] =~ m/^-/;
- $dgitrepos = shift @ARGV;
-
- die unless @ARGV;
- if ($ARGV[0] != m/^-/) {
- @ARGV == 1 or die;
- $pkg = shift @ARGV;
- } elsif ($ARGV[0] eq '--ssh') {
- shift @ARGV;
- !@ARGV or die;
- my $cmd = $ENV{'SSH_ORIGINAL_COMMAND'};
- $cmd =~ m{
- ^
- (?:\S*/)?
- (git-receive-pack|git-upload-pack)
- \s+
- (?:\S*/)?
- ($package_re)\.git
- $
- }ox
- or die "requested command $cmd not understood";
- $method = $1;
- $pkg = $2;
- my $func = $method;
- $func =~ y/-/_/;
- $func = $main::{"main__$func"};
- &$func;
+ $ENV{'DGIT_RPR_SUITES'} = argval();
+ $ENV{'DGIT_RPR_KEYRINGS'} = argval();
+ $dgitrepos = argval();
+
+ die unless @ARGV==1 && $ARGV[0] eq '--ssh';
+
+ my $cmd = $ENV{'SSH_ORIGINAL_COMMAND'};
+ $cmd =~ m{
+ ^
+ (?:\S*/)?
+ ([-0-9a-z]+)
+ \s+
+ (?:\S*/)?
+ ($package_re)\.git
+ $
+ }ox
+ or reject "command string not understood";
+ $method = $1;
+ $pkg = $2;
+ $realdestrepo = "$dgitrepos/$pkg.git";
+
+ my $funcn = $method;
+ $funcn =~ y/-/_/;
+ my $mainfunc = $main::{"main__$funcn"};
+
+ reject "unknown method" unless $mainfunc;
+
+ if (stat $realdestrepo) {
+ $destrepo = $realdestrepo;
} else {
- die;
+ $! == ENOENT or die "stat dest repo $destrepo: $!";
+ my $fixfunc = $main::{"fixmissing__$funcn"};
+ &$fixfunc;
}
- $destrepo = "$dgitrepos/$pkg.git";
+ &$mainfunc;
}
-sub main__git_receive_pack () {
- parseargs();
-fixme check method;
- makeworkingclone();
- setupstunthook();
- runcmd qw(git receive-pack), $destdir;
+sub unlockall () {
+ while (my $fh = pop $lockfhs) { close $fh; }
+}
+
+sub cleanup () {
+ unlockall();
+ chdir "$dgitrepos/_tmp" or die $!;
+ foreach my $lock (<*.lock>) {
+ my $tree = $lf;
+ $tree =~ s/\.lock$//;
+ next unless acquiretree($tree, 0);
+ remove $lock or warn $!;
+ unlockall();
+ }
}
+
+parseargsdispatch();
+cleanup();
~ianmdlvl / dgit.git / commitdiff