mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-24 23:06:16 +02:00
377 lines
12 KiB
Perl
Executable file
377 lines
12 KiB
Perl
Executable file
#! @perl@ -w @perlFlags@
|
||
|
||
use strict;
|
||
use Nix::Config;
|
||
use Nix::Manifest;
|
||
use Nix::Store;
|
||
use Nix::Utils;
|
||
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;
|
||
|
||
# ‘--insecure’ is fine because Nix verifies the hash of the result.
|
||
my $curl = "$Nix::Config::curl --fail --location --insecure";
|
||
|
||
|
||
# Open the manifest cache and update it if necessary.
|
||
my $dbh = updateManifestDB();
|
||
exit 0 unless defined $dbh; # exit if there are no manifests
|
||
print "\n";
|
||
|
||
|
||
# $hashCache->{$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 ($ARGV[0] eq "--query") {
|
||
|
||
while (<STDIN>) {
|
||
chomp;
|
||
my ($cmd, @args) = split " ", $_;
|
||
|
||
if ($cmd eq "have") {
|
||
foreach my $storePath (@args) {
|
||
print "$storePath\n" if scalar @{$dbh->selectcol_arrayref("select 1 from NARs where storePath = ?", {}, $storePath)} > 0;
|
||
}
|
||
print "\n";
|
||
}
|
||
|
||
elsif ($cmd eq "info") {
|
||
foreach my $storePath (@args) {
|
||
|
||
my $infos = $dbh->selectall_arrayref(
|
||
"select * from NARs where storePath = ?",
|
||
{ Slice => {} }, $storePath);
|
||
|
||
next unless scalar @{$infos} > 0;
|
||
my $info = @{$infos}[0];
|
||
|
||
print "$storePath\n";
|
||
print "$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";
|
||
}
|
||
|
||
print "\n";
|
||
}
|
||
|
||
else { die "unknown command `$cmd'"; }
|
||
}
|
||
|
||
exit 0;
|
||
}
|
||
|
||
elsif ($ARGV[0] ne "--substitute") {
|
||
die;
|
||
}
|
||
|
||
|
||
die unless scalar @ARGV == 3;
|
||
my $targetPath = $ARGV[1];
|
||
my $destPath = $ARGV[2];
|
||
$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 "$$ get $targetPath $date\n";
|
||
|
||
print STDERR "\n*** Trying to download/patch `$targetPath'\n";
|
||
|
||
|
||
# Compute the shortest path.
|
||
my @path = computeSmallestDownload $targetPath;
|
||
die "don't know how to produce $targetPath\n" if scalar @path == 0;
|
||
|
||
|
||
# We don't need the manifest anymore, so close it as an optimisation:
|
||
# if we still have SQLite locks blocking other processes (we
|
||
# shouldn't), this gets rid of them.
|
||
$dbh->disconnect;
|
||
|
||
|
||
# Traverse the shortest path, perform the actions described by the
|
||
# edges.
|
||
my $curStep = 1;
|
||
my $maxStep = scalar @path;
|
||
|
||
my $finalNarHash;
|
||
|
||
while (scalar @path > 0) {
|
||
my $edge = pop @path;
|
||
my $u = $edge->{start};
|
||
my $v = $edge->{end};
|
||
|
||
print STDERR "\n*** Step $curStep/$maxStep: ";
|
||
|
||
if ($edge->{type} eq "present") {
|
||
print STDERR "using already present path `$v'\n";
|
||
print LOGFILE "$$ 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 "$$ patch $patch->{url} $patch->{size} $patch->{baseHash} $u $v\n";
|
||
|
||
# Download the patch.
|
||
print STDERR " downloading patch...\n";
|
||
my $patchPath = "$tmpDir/patch";
|
||
checkURL $patch->{url};
|
||
system("$curl '$patch->{url}' -o $patchPath") == 0
|
||
or die "cannot download patch `$patch->{url}'\n";
|
||
|
||
# Apply the patch to the NAR archive produced in step 1 (for
|
||
# the already present path) or a later step (for patch sequences).
|
||
print STDERR " applying patch...\n";
|
||
system("$Nix::Config::libexecDir/bspatch $tmpNar $tmpNar2 $patchPath") == 0
|
||
or die "cannot apply patch `$patchPath' to $tmpNar\n";
|
||
|
||
if ($curStep < $maxStep) {
|
||
# The archive will be used as the base of the next patch.
|
||
rename "$tmpNar2", "$tmpNar" or die "cannot rename NAR archive: $!";
|
||
} else {
|
||
# This was the last patch. Unpack the final NAR archive
|
||
# into the target path.
|
||
print STDERR " unpacking patched archive...\n";
|
||
system("$Nix::Config::binDir/nix-store --restore $destPath < $tmpNar2") == 0
|
||
or die "cannot unpack $tmpNar2 to `$v'\n";
|
||
}
|
||
|
||
$finalNarHash = $patch->{narHash};
|
||
}
|
||
|
||
elsif ($edge->{type} eq "narfile") {
|
||
my $narFile = $edge->{info};
|
||
print STDERR "downloading `$narFile->{url}' to `$v'\n";
|
||
|
||
my $size = $narFile->{size} || -1;
|
||
print LOGFILE "$$ narfile $narFile->{url} $size $v\n";
|
||
|
||
checkURL $narFile->{url};
|
||
|
||
my $decompressor =
|
||
$narFile->{compressionType} eq "bzip2" ? "| $Nix::Config::bzip2 -d" :
|
||
$narFile->{compressionType} eq "xz" ? "| $Nix::Config::xz -d" :
|
||
$narFile->{compressionType} eq "none" ? "" :
|
||
die "unknown compression type `$narFile->{compressionType}'";
|
||
|
||
if ($curStep < $maxStep) {
|
||
# The archive will be used a base to a patch.
|
||
system("$curl '$narFile->{url}' $decompressor > $tmpNar") == 0
|
||
or die "cannot download and unpack `$narFile->{url}' to `$v'\n";
|
||
} else {
|
||
# Unpack the archive to the target path.
|
||
system("$curl '$narFile->{url}' $decompressor | $Nix::Config::binDir/nix-store --restore '$destPath'") == 0
|
||
or die "cannot download and unpack `$narFile->{url}' to `$v'\n";
|
||
}
|
||
|
||
$finalNarHash = $narFile->{narHash};
|
||
}
|
||
|
||
$curStep++;
|
||
}
|
||
|
||
|
||
# Tell Nix about the expected hash so it can verify it.
|
||
die "cannot check integrity of the downloaded path since its hash is not known\n"
|
||
unless defined $finalNarHash;
|
||
print "$finalNarHash\n";
|
||
|
||
|
||
print STDERR "\n";
|
||
print LOGFILE "$$ success\n";
|
||
close LOGFILE;
|