lix/perl/lib/Nix/CopyClosure.pm
Eelco Dolstra 56131a2709 Refactor
2014-07-24 12:24:25 +02:00

142 lines
4.8 KiB
Perl
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

package Nix::CopyClosure;
use strict;
use Nix::Config;
use Nix::Store;
use Nix::SSH;
use List::Util qw(sum);
use IPC::Open2;
sub copyToOpen {
my ($from, $to, $sshHost, $storePaths, $compressor, $decompressor,
$includeOutputs, $dryRun, $sign, $progressViewer, $useSubstitutes) = @_;
$useSubstitutes = 0 if $dryRun || !defined $useSubstitutes;
# Get the closure of this path.
my @closure = reverse(topoSortPaths(computeFSClosure(0, $includeOutputs,
map { followLinksToStorePath $_ } @{$storePaths})));
# Send the "query valid paths" command with the "lock" option
# enabled. This prevents a race where the remote host
# garbage-collect paths that are already there. Optionally, ask
# the remote host to substitute missing paths.
syswrite($to, pack("L<x4L<x4L<x4", 1, 1, $useSubstitutes)) or die;
writeStrings(\@closure, $to);
# Get back the set of paths that are already valid on the remote host.
my %present;
$present{$_} = 1 foreach readStrings($from);
my @missing = grep { !$present{$_} } @closure;
return if !@missing;
my $missingSize = 0;
$missingSize += (queryPathInfo($_, 1))[3] foreach @missing;
printf STDERR "copying %d missing paths (%.2f MiB) to $sshHost...\n",
scalar(@missing), $missingSize / (1024**2);
return if $dryRun;
# Send the "import paths" command.
syswrite($to, pack("L<x4", 4)) or die;
writeString($compressor, $to);
if ($compressor || $progressViewer) {
# Compute the size of the closure for the progress viewer.
$progressViewer = "$progressViewer -s $missingSize" if $progressViewer;
# Start the compressor and/or progress viewer in between us
# and the remote host.
my $to_;
my $pid2 = open2(">&" . fileno($to), $to_,
$progressViewer && $compressor ? "$progressViewer | $compressor" : $progressViewer || $compressor);
close $to;
exportPaths(fileno($to_), $sign, @missing);
close $to_;
waitpid $pid2, 0;
} else {
exportPaths(fileno($to), $sign, @missing);
}
readInt($from) == 1 or die "remote machine \`$sshHost' failed to import closure\n";
}
sub copyTo {
my ($sshHost, $sshOpts, $storePaths, $compressor, $decompressor,
$includeOutputs, $dryRun, $sign, $progressViewer, $useSubstitutes) = @_;
# Connect to the remote host.
my ($from, $to);
eval {
($from, $to) = connectToRemoteNix($sshHost, $sshOpts);
};
if ($@) {
chomp $@;
warn "$@; falling back to old closure copying method\n";
return oldCopyTo(@_);
}
copyToOpen($from, $to, $sshHost, $storePaths, $compressor, $decompressor,
$includeOutputs, $dryRun, $sign, $progressViewer, $useSubstitutes);
close $to;
}
# For backwards compatibility with Nix <= 1.7. Will be removed
# eventually.
sub oldCopyTo {
my ($sshHost, $sshOpts, $storePaths, $compressor, $decompressor,
$includeOutputs, $dryRun, $sign, $progressViewer, $useSubstitutes) = @_;
# Get the closure of this path.
my @closure = reverse(topoSortPaths(computeFSClosure(0, $includeOutputs,
map { followLinksToStorePath $_ } @{$storePaths})));
# Optionally use substitutes on the remote host.
if (!$dryRun && $useSubstitutes) {
system "ssh $sshHost @{$sshOpts} nix-store -r --ignore-unknown @closure";
# Ignore exit status because this is just an optimisation.
}
# Ask the remote host which paths are invalid. Because of limits
# to the command line length, do this in chunks. Eventually,
# we'll want to use --from-stdin, but we can't rely on the
# target having this option yet.
my @missing;
my $missingSize = 0;
while (scalar(@closure) > 0) {
my @ps = splice(@closure, 0, 1500);
open(READ, "set -f; ssh $sshHost @{$sshOpts} nix-store --check-validity --print-invalid @ps|");
while (<READ>) {
chomp;
push @missing, $_;
my ($deriver, $narHash, $time, $narSize, $refs) = queryPathInfo($_, 1);
$missingSize += $narSize;
}
close READ or die;
}
$compressor = "$compressor |" if $compressor ne "";
$decompressor = "$decompressor |" if $decompressor ne "";
$progressViewer = "$progressViewer -s $missingSize |" if $progressViewer ne "";
# Export the store paths and import them on the remote machine.
if (scalar @missing > 0) {
print STDERR "copying ", scalar @missing, " missing paths to $sshHost...\n";
unless ($dryRun) {
open SSH, "| $progressViewer $compressor ssh $sshHost @{$sshOpts} '$decompressor nix-store --import' > /dev/null" or die;
exportPaths(fileno(SSH), $sign, @missing);
close SSH or die "copying store paths to remote machine `$sshHost' failed: $?";
}
}
}
1;