#!/usr/bin/perl -w
#
# git caching proxy
-#
+
# usage: run it on some port, and then clone or fetch
# "git://<realhost>:<realport>/<real-git-url>[ <options>]"
# where <real-git-url> is http://<host>/... or git://<host>/...
# fetch=try use what is in the cache if the fetch/clone fails
# timeout=<seconds> length of time to allow for fetch/clone
+# git-cache-proxy is free software; you can redistribute it and/or
+# modify them under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 3, or (at
+# your option) any later version.
+#
+# git-cache-proxy is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, consult the Free Software Foundation's
+# website at www.fsf.org, or the GNU Project website at www.gnu.org.
+#
+# (Some code taken from userv-utils's git-daemon.in and git-service.in
+# which were written by Tony Finch <dot@dotat.at> and subsequently
+# heavily modified by Ian Jackson <ijackson@chiark.greenend.org.uk>
+# and were released under CC0 1.0. The whole program is now GPLv3+.)
+
use strict;
use warnings;
use Socket;
use Sys::Syslog;
use Fcntl qw(:flock SEEK_SET);
+use File::Path qw(remove_tree);
our $us = 'git-cache-proxy';
+
+#---------- error handling and logging ----------
+
+# This is a bit fiddly, because we want to catch errors sent to stderr
+# and dump them to syslog if we can, but only if we are running as an
+# inetd service.
+
our $log; # filehandle (ref), or "1" meaning syslog
-BEGIN {
- open STDERR, ">/dev/null" or exit 255;
- open TEMPERR, "+>", undef or exit 255;
- open STDERR, ">&TEMPERR" or exit 255;
+sub ntoa {
+ my $sockaddr = shift;
+ return ('(local)') unless defined $sockaddr;
+ my ($port,$addr) = sockaddr_in $sockaddr;
+ $addr = inet_ntoa $addr;
+ return ("[$addr]:$port",$addr,$port);
+}
- sub ntoa {
- my $sockaddr = shift;
- return ('(local)') unless defined $sockaddr;
- my ($port,$addr) = sockaddr_in $sockaddr;
- $addr = inet_ntoa $addr;
- return ("[$addr]:$port",$addr,$port);
- }
+our ($client) = ntoa getpeername STDIN;
+our ($server) = ntoa getsockname STDIN;
- our ($client,$client_addr,$client_port) = ntoa getpeername STDIN;
- our ($server,$server_addr,$server_port) = ntoa getsockname STDIN;
+sub ensurelog () {
+ return if $log;
+ openlog $us, qw(pid), 'daemon';
+ $log = 1;
+}
- sub ensurelog () {
- return if $log;
- openlog $us, qw(pid), 'daemon';
- $log = 1;
+sub logm ($$) {
+ my ($pri, $msg) = @_;
+ if ($client eq '(local)') {
+ print STDERR "$us: $pri: $msg\n" or die $!;
+ exit 1;
}
-
- sub logm ($$) {
- my ($pri, $msg) = @_;
- ensurelog();
- my $mainmsg = sprintf "%s-%s: %s", $server, $client, $msg;
- if (ref $log) {
- my $wholemsg = sprintf("%s [%d] %s: %s\n",
- strftime("%Y-%m-%d %H:%M:%S Z", gmtime),
- $$,
- $pri,
- $mainmsg);
- print $log $wholemsg;
- } else {
- syslog $pri, $mainmsg;
- }
+ ensurelog();
+ my $mainmsg = sprintf "%s-%s: %s", $server, $client, $msg;
+ if (ref $log) {
+ my $wholemsg = sprintf("%s [%d] %s: %s\n",
+ strftime("%Y-%m-%d %H:%M:%S Z", gmtime),
+ $$,
+ $pri,
+ $mainmsg);
+ print $log $wholemsg;
+ } else {
+ syslog $pri, $mainmsg;
}
+}
+
+if ($client ne '(local)') {
+ open STDERR, ">/dev/null" or exit 255;
+ open TEMPERR, "+>", undef or exit 255;
+ open STDERR, ">&TEMPERR" or exit 255;
+}
- END {
+END {
+ if ($client ne '(local)') {
if ($?) { logm 'crit', "crashing ($?)"; }
seek TEMPERR, 0, SEEK_SET;
while (<TEMPERR>) {
chomp;
logm 'crit', $_;
}
- exit $?;
}
+ exit $?;
}
-our $fetchtimeout = 1800;
-our $maxfetchtimeout = 3600;
-
sub fail ($) {
my ($msg) = @_;
logm 'err', $msg;
exit 0;
}
+#---------- argument parsing ----------
+
+our $housekeepingthreshdays = 1;
+our $treeexpiredays = 21;
+our $fetchtimeout = 1800;
+our $maxfetchtimeout = 3600;
our $cachedir = '/var/cache/git-cache-proxy';
for (;;) {
!@ARGV or fail "bad usage: no non-option arguments permitted";
-chdir $cachedir or fail "chdir $cachedir: $!";
+#---------- main program ----------
-our ($service,$specpath,$spechost);
+chdir $cachedir or fail "chdir $cachedir: $!";
-$SIG{ALRM} = sub { fail "timeout" };
-alarm 30;
+our ($service,$specpath,$spechost,$subdir);
+our ($tmpd,$gitd,$lock);
+our ($fetch,$url);
sub xread {
my $length = shift;
my $buffer = "";
while ($length > length $buffer) {
my $ret = sysread STDIN, $buffer, $length, length $buffer;
- fail "Expected $length bytes, got ".length $buffer
+ fail "expected $length bytes, got ".length $buffer
if defined $ret and $ret == 0;
fail "read: $!" if not defined $ret and $! != EINTR and $! != EAGAIN;
}
return $buffer;
}
-my $hex_len = xread 4;
-fail "Bad hex in packet length" unless $hex_len =~ m|^[0-9a-fA-F]{4}$|;
-my $line = xread -4 + hex $hex_len;
-unless (($service,$specpath,$spechost) = $line =~
- m|^(git-[a-z-]+) /*([!-~ ]+)\0host=([!-~]+)\0$|) {
- $line =~ s|[^ -~]+| |g;
- gitfail "unknown/unsupported instruction `$line'"
+
+sub servinfo ($) {
+ my ($msg) = @_;
+ logm 'info', "service `$specpath': $msg";
}
-alarm 0;
-
-$service eq 'git-upload-pack'
- or gitfail "unknown/unsupported service `$service'";
-
-my $fetch = 2; # 0:don't; 1:try; 2:force
-my $url = $specpath;
-
-while ($url =~ s#\s+(\[)([^][{}]+)\]$## ||
- $url =~ s#\s+(\{)([^][{}]+)\}$##) {
- $_ = $2;
- my $must = $1 eq '{';
- if (m/^fetch=try$/) {
- $fetch = 1;
- } elsif (m/^fetch=no$/) {
- $fetch = 0;
- } elsif (m/^fetch=must$/) {
- $fetch = 2; # the default
- } elsif (m/^timeout=(\d+)$/) {
- $fetchtimeout = $1 <= $maxfetchtimeout ? $1 : $maxfetchtimeout;
- } elsif ($must) {
- gitfail "unknown/unsupported option `$_'";
+sub readcommand () {
+ $SIG{ALRM} = sub { fail "timeout" };
+ alarm 30;
+
+ my $hex_len = xread 4;
+ fail "Bad hex in packet length" unless $hex_len =~ m|^[0-9a-fA-F]{4}$|;
+ my $line = xread -4 + hex $hex_len;
+ unless (($service,$specpath,$spechost) = $line =~
+ m|^(git-[a-z-]+) /*([!-~ ]+)\0host=([!-~]+)\0$|) {
+ $line =~ s|[^ -~]+| |g;
+ gitfail "unknown/unsupported instruction `$line'"
+ }
+
+ alarm 0;
+
+ $service eq 'git-upload-pack'
+ or gitfail "unknown/unsupported service `$service'";
+
+ $fetch = 2; # 0:don't; 1:try; 2:force
+ $url = $specpath;
+
+ while ($url =~ s#\s+(\[)([^][{}]+)\]$## ||
+ $url =~ s#\s+(\{)([^][{}]+)\}$##) {
+ $_ = $2;
+ my $must = $1 eq '{';
+ if (m/^fetch=try$/) {
+ $fetch = 1;
+ } elsif (m/^fetch=no$/) {
+ $fetch = 0;
+ } elsif (m/^fetch=must$/) {
+ $fetch = 2; # the default
+ } elsif (m/^timeout=(\d+)$/) {
+ $fetchtimeout = $1 <= $maxfetchtimeout ? $1 : $maxfetchtimeout;
+ } elsif ($must) {
+ gitfail "unknown/unsupported option `$_'";
+ }
}
-}
-$url =~ m{^(?:https?|git)://[-.0-9a-z]+/}
- or gitfail "unknown/unsupported url scheme or format `$url'";
+ $url =~ m{^(?:https?|git)://[-.0-9a-z]+/}
+ or gitfail "unknown/unsupported url scheme or format `$url'";
-our $subdir = $url;
-$subdir =~ s|\\|\\\\|g;
-$subdir =~ s|,|\\,|g;
-$subdir =~ s|/|,|g;
+ $subdir = $url;
+ $subdir =~ s|\\|\\\\|g;
+ $subdir =~ s|,|\\,|g;
+ $subdir =~ s|/|,|g;
-logm 'info', "$specpath locking";
+ $tmpd= "$subdir\\.tmp";
+ $gitd= "$subdir\\.git";
+ $lock = "$subdir\\.lock";
-my $tmpd= "$subdir\\.tmp";
-my $gitd= "$subdir\\.git";
-my $lock = "$subdir\\.lock";
+ servinfo "locking";
+}
-for (;;) {
+sub clonefetch () {
open LOCK, "+>", $lock or fail "open/create $lock: $!";
flock LOCK, LOCK_EX or fail "lock exclusive $lock: $!";
- my $exists = stat $gitd;
- $exists or $!==ENOENT or fail "stat $gitd: $!";
+ my $exists = lstat $gitd;
+ $exists or $!==ENOENT or fail "lstat $gitd: $!";
our $fetchfail = '';
if (!$exists) {
system qw(rm -rf --), $tmpd;
@cmd = (qw(git clone -q --mirror), $url, $tmpd);
- logm 'info', "$specpath cloning @cmd";
+ servinfo "cloning";
} else {
@cmd = (qw(git remote update --prune));
- logm 'info', "$specpath fetching @cmd";
+ servinfo "fetching";
}
my $cmd = "@cmd[0..1]";
my $timedout = 0;
{
local $SIG{ALRM} = sub {
- logm 'info', "$specpath fetch/clone timeout";
+ servinfo "fetch/clone timeout";
$timedout=1; kill 9, -$child;
};
-logm 'info', "timeout=$fetchtimeout";
alarm($fetchtimeout);
$!=0; { local $/=undef; $fetcherr = <FETCHERR>; }
!FETCHERR->error or fail "read pipe from fetch/clone: $!";
if ($fetch >= 2) {
gitfail $fetchfail;
} else {
- logm 'info', "$specpath fetch/clone failed: $fetchfail";
+ servinfo "fetch/clone failed: $fetchfail";
}
}
gitfail "no cached data, and not cloned: $fetchfail";
}
- logm 'info', "$specpath sharing";
+ servinfo "sharing";
flock LOCK, LOCK_UN or fail "unlock $lock: $!";
flock LOCK, LOCK_SH or fail "lock shared $lock: $!";
# actually, just relocking as shared would have the same semantics
# but it's best to be explicit
if (chdir $gitd) {
- last;
+ return 1;
}
$!==ENOENT or fail "chdir $gitd: $!";
# Well, err, someone must have taken the lock in between
# and garbage collected it. How annoying.
+ return 0;
+}
+
+sub housekeeping () {
+ foreach $lock (<[a-z]*\\.lock>) {
+ if (!lstat $lock) {
+ $! == ENOENT or fail "housekeeping: $lock: lstat: $!";
+ next;
+ }
+ if (-M _ <= $treeexpiredays) {
+ logm 'debug', "housekeeping: $lock: not too old";
+ next;
+ }
+ my $subdir = $lock; $subdir =~ s/\\.lock$//;
+ my $ok = 1;
+ foreach my $suffix (qw(tmp git)) {
+ my $dir = "${subdir}\\.$suffix";
+ my $errs;
+ remove_tree($dir, { safe=>1, error=>\$errs });
+ $ok = 0 if @$errs;
+ foreach my $err (@$errs) {
+ logm 'warning', "problem deleting: $err[0]: $err[1]";
+ }
+ }
+ if ($ok) {
+
+
+sub housekeepingcheck ($$) {
+ my ($dofork, $force) = @_;
+ open HLOCK, "+>", "Housekeeping.lock"
+ or fail "open/create Housekeeping.lock: $!";
+ if (!$force) {
+ if (flock HLOCK, LOCK_EX|LOCK_NB) {
+ logm 'debug', "housekeeping lock taken, not running";
+ close HLOCK;
+ return 0;
+ }
+ }
+ if ($force) {
+ logm 'info', "housekeeping forced";
+ } elsif (!lstat "Housekeeping.stamp") {
+ $! == ENOENT or fail "lstat Housekeeping.stamp: $!";
+ logm 'info', "housekeeping stamp missing, will run";
+ } elsif (-M _ <= $housekeepingthreshdays) {
+ logm 'debug', "housekeeping done recently";
+ close HLOCK;
+ return 0;
+ }
+ if ($dofork) {
+ my $child = fork;
+ defined $child or fail "fork for housekeeping: $!";
+ if (!$child) {
+ housekeeping();
+ exit 0;
+ }
+ return 1;
+ } else {
+ housekeeping();
+ return 1;
+ }
+}
+
+sub runcommand () {
+ servinfo "servicing";
+ exec qw(git-upload-pack --strict --timeout=1000 .)
+ or fail "exec git-upload-pack: $!";
+}
+
+sub daemonservice () {
+ readcommand();
+ while (!clonefetch()) { }
+ runcommand();
}
-logm 'info', "$specpath servicing";
-exec qw(git-upload-pack --strict --timeout=1000 .)
- or fail "exec git-upload-pack: $!";
+daemonservice();
~ian / chiark-utils.git / blobdiff