From: Ben Peart <benpeart@xxxxxxxxxxxxx> Signed-off-by: Ben Peart <benpeart@xxxxxxxxxxxxx> Signed-off-by: Christian Couder <chriscool@xxxxxxxxxxxxx> --- contrib/long-running-read-object/example.pl | 114 ++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 contrib/long-running-read-object/example.pl diff --git a/contrib/long-running-read-object/example.pl b/contrib/long-running-read-object/example.pl new file mode 100644 index 0000000000..6587333b87 --- /dev/null +++ b/contrib/long-running-read-object/example.pl @@ -0,0 +1,114 @@ +#!/usr/bin/perl +# +# Example implementation for the Git read-object protocol version 1 +# See Documentation/technical/read-object-protocol.txt +# +# Allows you to test the ability for blobs to be pulled from a host git repo +# "on demand." Called when git needs a blob it couldn't find locally due to +# a lazy clone that only cloned the commits and trees. +# +# A lazy clone can be simulated via the following commands from the host repo +# you wish to create a lazy clone of: +# +# cd /host_repo +# git rev-parse HEAD +# git init /guest_repo +# git cat-file --batch-check --batch-all-objects | grep -v 'blob' | +# cut -d' ' -f1 | git pack-objects /e/guest_repo/.git/objects/pack/noblobs +# cd /guest_repo +# git config core.virtualizeobjects true +# git reset --hard <sha from rev-parse call above> +# +# Please note, this sample is a minimal skeleton. No proper error handling +# was implemented. +# + +use strict; +use warnings; + +# +# Point $DIR to the folder where your host git repo is located so we can pull +# missing objects from it +# +my $DIR = "/host_repo/.git/"; + +sub packet_bin_read { + my $buffer; + my $bytes_read = read STDIN, $buffer, 4; + if ( $bytes_read == 0 ) { + + # EOF - Git stopped talking to us! + exit(); + } + elsif ( $bytes_read != 4 ) { + die "invalid packet: '$buffer'"; + } + my $pkt_size = hex($buffer); + if ( $pkt_size == 0 ) { + return ( 1, "" ); + } + elsif ( $pkt_size > 4 ) { + my $content_size = $pkt_size - 4; + $bytes_read = read STDIN, $buffer, $content_size; + if ( $bytes_read != $content_size ) { + die "invalid packet ($content_size bytes expected; $bytes_read bytes read)"; + } + return ( 0, $buffer ); + } + else { + die "invalid packet size: $pkt_size"; + } +} + +sub packet_txt_read { + my ( $res, $buf ) = packet_bin_read(); + unless ( $buf =~ s/\n$// ) { + die "A non-binary line MUST be terminated by an LF."; + } + return ( $res, $buf ); +} + +sub packet_bin_write { + my $buf = shift; + print STDOUT sprintf( "%04x", length($buf) + 4 ); + print STDOUT $buf; + STDOUT->flush(); +} + +sub packet_txt_write { + packet_bin_write( $_[0] . "\n" ); +} + +sub packet_flush { + print STDOUT sprintf( "%04x", 0 ); + STDOUT->flush(); +} + +( packet_txt_read() eq ( 0, "git-read-object-client" ) ) || die "bad initialize"; +( packet_txt_read() eq ( 0, "version=1" ) ) || die "bad version"; +( packet_bin_read() eq ( 1, "" ) ) || die "bad version end"; + +packet_txt_write("git-read-object-server"); +packet_txt_write("version=1"); +packet_flush(); + +( packet_txt_read() eq ( 0, "capability=get" ) ) || die "bad capability"; +( packet_bin_read() eq ( 1, "" ) ) || die "bad capability end"; + +packet_txt_write("capability=get"); +packet_flush(); + +while (1) { + my ($command) = packet_txt_read() =~ /^command=([^=]+)$/; + + if ( $command eq "get" ) { + my ($sha1) = packet_txt_read() =~ /^sha1=([0-9a-f]{40})$/; + packet_bin_read(); + + system ('git --git-dir="' . $DIR . '" cat-file blob ' . $sha1 . ' | git -c core.virtualizeobjects=false hash-object -w --stdin >/dev/null 2>&1'); + packet_txt_write(($?) ? "status=error" : "status=success"); + packet_flush(); + } else { + die "bad command '$command'"; + } +} -- 2.13.1.565.gbfcd7a9048