tvl-depot/scripts/nix-pull
2003-07-10 19:27:46 +00:00

73 lines
2 KiB
Perl

#! /usr/bin/perl -w
my $prefix = $ENV{"NIX"} || "/tmp/nix"; # !!! use prefix
my $etcdir = "$prefix/etc/nix";
my $tmpfile = "$prefix/var/nix/pull.tmp";
my $conffile = "$etcdir/prebuilts.conf";
my @subs;
open CONFFILE, "<$conffile";
while (<CONFFILE>) {
chomp;
if (/^\s*(\S+)\s*(\#.*)?$/) {
my $url = $1;
print "obtaining list of Nix archives at $url...\n";
system "wget '$url' -O '$tmpfile' 2> /dev/null"; # !!! escape
if ($?) { die "`wget' failed"; }
open INDEX, "<$tmpfile";
while (<INDEX>) {
# Get all links to prebuilts, that is, file names of the
# form foo-HASH-HASH.tar.bz2.
next unless (/HREF=\"([^\"]*)\"/);
my $fn = $1;
next if $fn =~ /\.\./;
next if $fn =~ /\//;
next unless $fn =~ /([0-9a-z]{32})-([0-9a-z]{32})\.nar/;
my $hash = $2;
print "registering $hash -> $url/$fn\n";
# Construct a Fix expression that fetches and unpacks a
# Nix archive from the network.
my $fetch =
"App(IncludeFix(\"fetchurl/fetchurl.fix\"), " .
"[(\"url\", \"$url/$fn\"), (\"hash\", \"\")])";
my $fixexpr =
"App(IncludeFix(\"nar/unnar.fix\"), " .
"[ (\"nar\", $fetch)" .
", (\"name\", \"fetched-$hash\")" .
"])";
my $fixfile = "/tmp/nix-pull-tmp.fix";
open FIX, ">$fixfile";
print FIX $fixexpr;
close FIX;
# Instantiate a Nix expression from the Fix expression.
my $nhash = `fix $fixfile`;
$? and die "instantiating Nix archive expression";
chomp $nhash;
die unless $nhash =~ /^([0-9a-z]{32})$/;
push @subs, $hash;
push @subs, $nhash;
}
close INDEX;
unlink $tmpfile;
}
}
system "nix --substitute @subs";
if ($?) { die "`nix --substitute' failed"; }