388 lines
12 KiB
Perl
Executable File
388 lines
12 KiB
Perl
Executable File
#! @perl@ -w @perlFlags@
|
|
|
|
use strict;
|
|
use Nix::Config;
|
|
use Nix::Manifest;
|
|
use Nix::Store;
|
|
use POSIX qw(strftime);
|
|
use File::Temp qw(tempdir);
|
|
|
|
STDOUT->autoflush(1);
|
|
|
|
my $logFile = "$Nix::Config::logDir/downloads";
|
|
|
|
# For queries, skip expensive calls to nix-hash etc. We're just
|
|
# estimating the expected download size.
|
|
my $fast = 1;
|
|
|
|
|
|
# Open the manifest cache and update it if necessary.
|
|
my $dbh = updateManifestDB();
|
|
|
|
|
|
# $hashCache->{$algo}->{$path} yields the $algo-hash of $path.
|
|
my $hashCache;
|
|
|
|
|
|
sub parseHash {
|
|
my $hash = shift;
|
|
if ($hash =~ /^(.+):(.+)$/) {
|
|
return ($1, $2);
|
|
} else {
|
|
return ("md5", $hash);
|
|
}
|
|
}
|
|
|
|
|
|
# Compute the most efficient sequence of downloads to produce the
|
|
# given path.
|
|
sub computeSmallestDownload {
|
|
my $targetPath = shift;
|
|
|
|
# Build a graph of all store paths that might contribute to the
|
|
# construction of $targetPath, and the special node "start". The
|
|
# edges are either patch operations, or downloads of full NAR
|
|
# files. The latter edges only occur between "start" and a store
|
|
# path.
|
|
my %graph;
|
|
|
|
$graph{"start"} = {d => 0, pred => undef, edges => []};
|
|
|
|
my @queue = ();
|
|
my $queueFront = 0;
|
|
my %done;
|
|
|
|
sub addNode {
|
|
my $graph = shift;
|
|
my $u = shift;
|
|
$$graph{$u} = {d => 999999999999, pred => undef, edges => []}
|
|
unless defined $$graph{$u};
|
|
}
|
|
|
|
sub addEdge {
|
|
my $graph = shift;
|
|
my $u = shift;
|
|
my $v = shift;
|
|
my $w = shift;
|
|
my $type = shift;
|
|
my $info = shift;
|
|
addNode $graph, $u;
|
|
push @{$$graph{$u}->{edges}},
|
|
{weight => $w, start => $u, end => $v, type => $type, info => $info};
|
|
my $n = scalar @{$$graph{$u}->{edges}};
|
|
}
|
|
|
|
push @queue, $targetPath;
|
|
|
|
while ($queueFront < scalar @queue) {
|
|
my $u = $queue[$queueFront++];
|
|
next if defined $done{$u};
|
|
$done{$u} = 1;
|
|
|
|
addNode \%graph, $u;
|
|
|
|
# If the path already exists, it has distance 0 from the
|
|
# "start" node.
|
|
if (isValidPath($u)) {
|
|
addEdge \%graph, "start", $u, 0, "present", undef;
|
|
}
|
|
|
|
else {
|
|
|
|
# Add patch edges.
|
|
my $patchList = $dbh->selectall_arrayref(
|
|
"select * from Patches where storePath = ?",
|
|
{ Slice => {} }, $u);
|
|
|
|
foreach my $patch (@{$patchList}) {
|
|
if (isValidPath($patch->{basePath})) {
|
|
my ($baseHashAlgo, $baseHash) = parseHash $patch->{baseHash};
|
|
|
|
my $hash = $hashCache->{$baseHashAlgo}->{$patch->{basePath}};
|
|
if (!defined $hash) {
|
|
$hash = $fast && $baseHashAlgo eq "sha256"
|
|
? queryPathHash($patch->{basePath})
|
|
: hashPath($baseHashAlgo, $baseHashAlgo ne "md5", $patch->{basePath});
|
|
$hash =~ s/.*://;
|
|
$hashCache->{$baseHashAlgo}->{$patch->{basePath}} = $hash;
|
|
}
|
|
|
|
next if $hash ne $baseHash;
|
|
}
|
|
push @queue, $patch->{basePath};
|
|
addEdge \%graph, $patch->{basePath}, $u, $patch->{size}, "patch", $patch;
|
|
}
|
|
|
|
# Add NAR file edges to the start node.
|
|
my $narFileList = $dbh->selectall_arrayref(
|
|
"select * from NARs where storePath = ?",
|
|
{ Slice => {} }, $u);
|
|
|
|
foreach my $narFile (@{$narFileList}) {
|
|
# !!! how to handle files whose size is not known in advance?
|
|
# For now, assume some arbitrary size (1 GB).
|
|
# This has the side-effect of preferring non-Hydra downloads.
|
|
addEdge \%graph, "start", $u, ($narFile->{size} || 1000000000), "narfile", $narFile;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
# Run Dijkstra's shortest path algorithm to determine the shortest
|
|
# sequence of download and/or patch actions that will produce
|
|
# $targetPath.
|
|
|
|
my @todo = keys %graph;
|
|
|
|
while (scalar @todo > 0) {
|
|
|
|
# Remove the closest element from the todo list.
|
|
# !!! inefficient, use a priority queue
|
|
@todo = sort { -($graph{$a}->{d} <=> $graph{$b}->{d}) } @todo;
|
|
my $u = pop @todo;
|
|
|
|
my $u_ = $graph{$u};
|
|
|
|
foreach my $edge (@{$u_->{edges}}) {
|
|
my $v_ = $graph{$edge->{end}};
|
|
if ($v_->{d} > $u_->{d} + $edge->{weight}) {
|
|
$v_->{d} = $u_->{d} + $edge->{weight};
|
|
# Store the edge; to edge->start is actually the
|
|
# predecessor.
|
|
$v_->{pred} = $edge;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
# Retrieve the shortest path from "start" to $targetPath.
|
|
my @path = ();
|
|
my $cur = $targetPath;
|
|
return () unless defined $graph{$targetPath}->{pred};
|
|
while ($cur ne "start") {
|
|
push @path, $graph{$cur}->{pred};
|
|
$cur = $graph{$cur}->{pred}->{start};
|
|
}
|
|
|
|
return @path;
|
|
}
|
|
|
|
|
|
# Parse the arguments.
|
|
|
|
if ($ARGV[0] eq "--query") {
|
|
|
|
while (<STDIN>) {
|
|
my $cmd = $_; chomp $cmd;
|
|
|
|
if ($cmd eq "have") {
|
|
my $storePath = <STDIN>; chomp $storePath;
|
|
print STDOUT (
|
|
scalar @{$dbh->selectcol_arrayref("select 1 from NARs where storePath = ?", {}, $storePath)} > 0
|
|
? "1\n" : "0\n");
|
|
}
|
|
|
|
elsif ($cmd eq "info") {
|
|
my $storePath = <STDIN>; chomp $storePath;
|
|
|
|
my $infos = $dbh->selectall_arrayref(
|
|
"select * from NARs where storePath = ?",
|
|
{ Slice => {} }, $storePath);
|
|
|
|
my $info;
|
|
if (scalar @{$infos} > 0) {
|
|
$info = @{$infos}[0];
|
|
}
|
|
else {
|
|
print "0\n";
|
|
next; # not an error
|
|
}
|
|
|
|
print "1\n";
|
|
print "$info->{deriver}\n";
|
|
my @references = split " ", $info->{refs};
|
|
print scalar @references, "\n";
|
|
print "$_\n" foreach @references;
|
|
|
|
my @path = computeSmallestDownload $storePath;
|
|
|
|
my $downloadSize = 0;
|
|
while (scalar @path > 0) {
|
|
my $edge = pop @path;
|
|
my $u = $edge->{start};
|
|
my $v = $edge->{end};
|
|
if ($edge->{type} eq "patch") {
|
|
$downloadSize += $edge->{info}->{size} || 0;
|
|
}
|
|
elsif ($edge->{type} eq "narfile") {
|
|
$downloadSize += $edge->{info}->{size} || 0;
|
|
}
|
|
}
|
|
|
|
print "$downloadSize\n";
|
|
|
|
my $narSize = $info->{narSize} || 0;
|
|
print "$narSize\n";
|
|
}
|
|
|
|
else { die "unknown command `$cmd'"; }
|
|
}
|
|
|
|
exit 0;
|
|
}
|
|
|
|
elsif ($ARGV[0] ne "--substitute") {
|
|
die;
|
|
}
|
|
|
|
|
|
die unless scalar @ARGV == 2;
|
|
my $targetPath = $ARGV[1];
|
|
$fast = 0;
|
|
|
|
|
|
# Create a temporary directory.
|
|
my $tmpDir = tempdir("nix-download.XXXXXX", CLEANUP => 1, TMPDIR => 1)
|
|
or die "cannot create a temporary directory";
|
|
|
|
my $tmpNar = "$tmpDir/nar";
|
|
my $tmpNar2 = "$tmpDir/nar2";
|
|
|
|
|
|
open LOGFILE, ">>$logFile" or die "cannot open log file $logFile";
|
|
|
|
my $date = strftime ("%F %H:%M:%S UTC", gmtime (time));
|
|
print LOGFILE "$$ get $targetPath $date\n";
|
|
|
|
print STDERR "\n*** Trying to download/patch `$targetPath'\n";
|
|
|
|
|
|
# Compute the shortest path.
|
|
my @path = computeSmallestDownload $targetPath;
|
|
die "don't know how to produce $targetPath\n" if scalar @path == 0;
|
|
|
|
|
|
# We don't need the manifest anymore, so close it as an optimisation:
|
|
# if we still have SQLite locks blocking other processes (we
|
|
# shouldn't), this gets rid of them.
|
|
$dbh->disconnect;
|
|
|
|
|
|
# Traverse the shortest path, perform the actions described by the
|
|
# edges.
|
|
my $curStep = 1;
|
|
my $maxStep = scalar @path;
|
|
|
|
sub downloadFile {
|
|
my $url = shift;
|
|
$ENV{"PRINT_PATH"} = 1;
|
|
$ENV{"QUIET"} = 1;
|
|
my ($hash, $path) = `$Nix::Config::binDir/nix-prefetch-url '$url'`;
|
|
die "download of `$url' failed" . ($! ? ": $!" : "") . "\n" unless $? == 0;
|
|
chomp $path;
|
|
return $path;
|
|
}
|
|
|
|
my $finalNarHash;
|
|
|
|
while (scalar @path > 0) {
|
|
my $edge = pop @path;
|
|
my $u = $edge->{start};
|
|
my $v = $edge->{end};
|
|
|
|
print STDERR "\n*** Step $curStep/$maxStep: ";
|
|
|
|
if ($edge->{type} eq "present") {
|
|
print STDERR "using already present path `$v'\n";
|
|
print LOGFILE "$$ present $v\n";
|
|
|
|
if ($curStep < $maxStep) {
|
|
# Since this is not the last step, the path will be used
|
|
# as a base to one or more patches. So turn the base path
|
|
# into a NAR archive, to which we can apply the patch.
|
|
print STDERR " packing base path...\n";
|
|
system("$Nix::Config::binDir/nix-store --dump $v > $tmpNar") == 0
|
|
or die "cannot dump `$v'";
|
|
}
|
|
}
|
|
|
|
elsif ($edge->{type} eq "patch") {
|
|
my $patch = $edge->{info};
|
|
print STDERR "applying patch `$patch->{url}' to `$u' to create `$v'\n";
|
|
|
|
print LOGFILE "$$ patch $patch->{url} $patch->{size} $patch->{baseHash} $u $v\n";
|
|
|
|
# Download the patch.
|
|
print STDERR " downloading patch...\n";
|
|
my $patchPath = downloadFile "$patch->{url}";
|
|
|
|
# Apply the patch to the NAR archive produced in step 1 (for
|
|
# the already present path) or a later step (for patch sequences).
|
|
print STDERR " applying patch...\n";
|
|
system("$Nix::Config::libexecDir/bspatch $tmpNar $tmpNar2 $patchPath") == 0
|
|
or die "cannot apply patch `$patchPath' to $tmpNar";
|
|
|
|
if ($curStep < $maxStep) {
|
|
# The archive will be used as the base of the next patch.
|
|
rename "$tmpNar2", "$tmpNar" or die "cannot rename NAR archive: $!";
|
|
} else {
|
|
# This was the last patch. Unpack the final NAR archive
|
|
# into the target path.
|
|
print STDERR " unpacking patched archive...\n";
|
|
system("$Nix::Config::binDir/nix-store --restore $v < $tmpNar2") == 0
|
|
or die "cannot unpack $tmpNar2 into `$v'";
|
|
}
|
|
|
|
$finalNarHash = $patch->{narHash};
|
|
}
|
|
|
|
elsif ($edge->{type} eq "narfile") {
|
|
my $narFile = $edge->{info};
|
|
print STDERR "downloading `$narFile->{url}' into `$v'\n";
|
|
|
|
my $size = $narFile->{size} || -1;
|
|
print LOGFILE "$$ narfile $narFile->{url} $size $v\n";
|
|
|
|
# Download the archive.
|
|
print STDERR " downloading archive...\n";
|
|
my $narFilePath = downloadFile "$narFile->{url}";
|
|
|
|
if ($curStep < $maxStep) {
|
|
# The archive will be used a base to a patch.
|
|
system("$Nix::Config::bzip2 -d < '$narFilePath' > $tmpNar") == 0
|
|
or die "cannot unpack `$narFilePath' into `$v'";
|
|
} else {
|
|
# Unpack the archive into the target path.
|
|
print STDERR " unpacking archive...\n";
|
|
system("$Nix::Config::bzip2 -d < '$narFilePath' | $Nix::Config::binDir/nix-store --restore '$v'") == 0
|
|
or die "cannot unpack `$narFilePath' into `$v'";
|
|
}
|
|
|
|
$finalNarHash = $narFile->{narHash};
|
|
}
|
|
|
|
$curStep++;
|
|
}
|
|
|
|
|
|
# Make sure that the hash declared in the manifest matches what we
|
|
# downloaded and unpacked.
|
|
|
|
if (defined $finalNarHash) {
|
|
my ($hashAlgo, $hash) = parseHash $finalNarHash;
|
|
|
|
# The hash in the manifest can be either in base-16 or base-32.
|
|
# Handle both.
|
|
my $hash2 = hashPath($hashAlgo, $hashAlgo eq "sha256" && length($hash) != 64, $targetPath);
|
|
|
|
die "hash mismatch in downloaded path $targetPath; expected $hash, got $hash2\n"
|
|
if $hash ne $hash2;
|
|
} else {
|
|
die "cannot check integrity of the downloaded path since its hash is not known\n";
|
|
}
|
|
|
|
|
|
print STDERR "\n";
|
|
print LOGFILE "$$ success\n";
|
|
close LOGFILE;
|