mirror of
https://github.com/NixOS/nix.git
synced 2024-11-23 07:12:27 +00:00
133 lines
4.4 KiB
Plaintext
Executable File
133 lines
4.4 KiB
Plaintext
Executable File
#! @perl@ -w @perlFlags@
|
||
|
||
use utf8;
|
||
use strict;
|
||
use File::Basename;
|
||
use File::stat;
|
||
use Nix::Store;
|
||
use Nix::Config;
|
||
use Nix::Utils;
|
||
|
||
binmode STDERR, ":encoding(utf8)";
|
||
|
||
|
||
my $hashType = $ENV{'NIX_HASH_ALGO'} || "sha256"; # obsolete
|
||
my $cacheDir = $ENV{'NIX_DOWNLOAD_CACHE'};
|
||
|
||
my @args;
|
||
my $arg;
|
||
while ($arg = shift) {
|
||
if ($arg eq "--help") {
|
||
exec "man nix-prefetch-url" or die;
|
||
} elsif ($arg eq "--type") {
|
||
$hashType = shift;
|
||
die "$0: ‘$arg’ requires an argument\n" unless defined $hashType;
|
||
} elsif (substr($arg, 0, 1) eq "-") {
|
||
die "$0: unknown flag ‘$arg’\n";
|
||
} else {
|
||
push @args, $arg;
|
||
}
|
||
}
|
||
|
||
my $url = $args[0];
|
||
my $expHash = $args[1];
|
||
|
||
|
||
if (!defined $url || $url eq "") {
|
||
print STDERR <<EOF
|
||
Usage: nix-prefetch-url URL [EXPECTED-HASH]
|
||
EOF
|
||
;
|
||
exit 1;
|
||
}
|
||
|
||
my $tmpDir = mkTempDir("nix-prefetch-url");
|
||
|
||
# Hack to support the mirror:// scheme from Nixpkgs.
|
||
if ($url =~ /^mirror:\/\//) {
|
||
system("$Nix::Config::binDir/nix-build '<nixpkgs>' -A resolveMirrorURLs --argstr url '$url' -o $tmpDir/urls > /dev/null") == 0
|
||
or die "$0: nix-build failed; maybe \$NIX_PATH is not set properly\n";
|
||
my @expanded = split ' ', readFile("$tmpDir/urls");
|
||
die "$0: cannot resolve ‘$url’" unless scalar @expanded > 0;
|
||
print STDERR "$url expands to $expanded[0]\n";
|
||
$url = $expanded[0];
|
||
}
|
||
|
||
# Handle escaped characters in the URI. `+', `=' and `?' are the only
|
||
# characters that are valid in Nix store path names but have a special
|
||
# meaning in URIs.
|
||
my $name = basename $url;
|
||
die "cannot figure out file name for ‘$url’\n" if $name eq "";
|
||
$name =~ s/%2b/+/g;
|
||
$name =~ s/%3d/=/g;
|
||
$name =~ s/%3f/?/g;
|
||
|
||
my $finalPath;
|
||
my $hash;
|
||
|
||
# If the hash was given, a file with that hash may already be in the
|
||
# store.
|
||
if (defined $expHash) {
|
||
$finalPath = makeFixedOutputPath(0, $hashType, $expHash, $name);
|
||
if (isValidPath($finalPath)) { $hash = $expHash; } else { $finalPath = undef; }
|
||
}
|
||
|
||
# If we don't know the hash or a file with that hash doesn't exist,
|
||
# download the file and add it to the store.
|
||
if (!defined $finalPath) {
|
||
|
||
my $tmpFile = "$tmpDir/$name";
|
||
|
||
# Optionally do timestamp-based caching of the download.
|
||
# Actually, the only thing that we cache in $NIX_DOWNLOAD_CACHE is
|
||
# the hash and the timestamp of the file at $url. The caching of
|
||
# the file *contents* is done in Nix store, where it can be
|
||
# garbage-collected independently.
|
||
my ($cachedTimestampFN, $cachedHashFN, @cacheFlags);
|
||
if (defined $cacheDir) {
|
||
my $urlHash = hashString("sha256", 1, $url);
|
||
writeFile "$cacheDir/$urlHash.url", $url;
|
||
$cachedHashFN = "$cacheDir/$urlHash.$hashType";
|
||
$cachedTimestampFN = "$cacheDir/$urlHash.stamp";
|
||
@cacheFlags = ("--time-cond", $cachedTimestampFN) if -f $cachedHashFN && -f $cachedTimestampFN;
|
||
}
|
||
|
||
# Perform the download.
|
||
my @curlFlags = ("curl", $url, "-o", $tmpFile, "--fail", "--location", "--max-redirs", "20", "--disable-epsv", "--cookie-jar", "$tmpDir/cookies", "--remote-time", (split " ", ($ENV{NIX_CURL_FLAGS} || "")));
|
||
(system $Nix::Config::curl @curlFlags, @cacheFlags) == 0 or die "$0: download of ‘$url’ failed\n";
|
||
|
||
if (defined $cacheDir && ! -e $tmpFile) {
|
||
# Curl didn't create $tmpFile, so apparently there's no newer
|
||
# file on the server.
|
||
$hash = readFile $cachedHashFN or die;
|
||
$finalPath = makeFixedOutputPath(0, $hashType, $hash, $name);
|
||
unless (isValidPath $finalPath) {
|
||
print STDERR "cached contents of ‘$url’ disappeared, redownloading...\n";
|
||
$finalPath = undef;
|
||
(system $Nix::Config::curl @curlFlags) == 0 or die "$0: download of ‘$url’ failed\n";
|
||
}
|
||
}
|
||
|
||
if (!defined $finalPath) {
|
||
|
||
# Compute the hash.
|
||
$hash = hashFile($hashType, $hashType ne "md5", $tmpFile);
|
||
|
||
if (defined $cacheDir) {
|
||
writeFile $cachedHashFN, $hash;
|
||
my $st = stat($tmpFile) or die;
|
||
open STAMP, ">$cachedTimestampFN" or die; close STAMP;
|
||
utime($st->atime, $st->mtime, $cachedTimestampFN) or die;
|
||
}
|
||
|
||
# Add the downloaded file to the Nix store.
|
||
$finalPath = addToStore($tmpFile, 0, $hashType);
|
||
}
|
||
|
||
die "$0: hash mismatch for ‘$url’\n" if defined $expHash && $expHash ne $hash;
|
||
}
|
||
|
||
print STDERR "path is ‘$finalPath’\n" unless $ENV{'QUIET'};
|
||
print "$hash\n";
|
||
print "$finalPath\n" if $ENV{'PRINT_PATH'};
|