diff options
Diffstat (limited to 'scripts/nix-prefetch-url.in')
| -rwxr-xr-x | scripts/nix-prefetch-url.in | 233 |
1 files changed, 98 insertions, 135 deletions
diff --git a/scripts/nix-prefetch-url.in b/scripts/nix-prefetch-url.in index 45bad75f3e9f..eea2b814b733 100755 --- a/scripts/nix-prefetch-url.in +++ b/scripts/nix-prefetch-url.in @@ -1,165 +1,128 @@ -#! @shell@ -e - -url=$1 -expHash=$2 - -binDir=@bindir@ -if [ -n "$NIX_BIN_DIR" ]; then binDir="$NIX_BIN_DIR"; fi +#! @perl@ -w @perlFlags@ + +use strict; +use File::Basename; +use File::Temp qw(tempdir); +use File::stat; +use Nix::Store; +use Nix::Config; + +my $url = shift; +my $expHash = shift; +my $hashType = $ENV{'NIX_HASH_ALGO'} || "sha256"; +my $cacheDir = $ENV{'NIX_DOWNLOAD_CACHE'}; + +if (!defined $url || $url eq "") { + print STDERR <<EOF +Usage: nix-prefetch-url URL [EXPECTED-HASH] +EOF + ; + exit 1; +} -# needed to make it work on NixOS -export PATH=$PATH:@coreutils@ +sub writeFile { + my ($fn, $s) = @_; + open TMP, ">$fn" or die; + print TMP "$s" or die; + close TMP or die; +} -hashType=$NIX_HASH_ALGO -if test -z "$hashType"; then - hashType=sha256 -fi +sub readFile { + local $/ = undef; + my ($fn) = @_; + open TMP, "<$fn" or die; + my $s = <TMP>; + close TMP or die; + return $s; +} -hashFormat= -if test "$hashType" != "md5"; then - hashFormat=--base32 -fi +my $tmpDir = tempdir("nix-prefetch-url.XXXXXX", CLEANUP => 1, TMPDIR => 1) + or die "cannot create a temporary directory"; -if test -z "$url"; then - echo "syntax: nix-prefetch-url URL [EXPECTED-HASH]" >&2 - exit 1 -fi +# 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 = $expanded[0]; +} # Handle escaped characters in the URI. `+', `=' and `?' are the only # characters that are valid in Nix store path names but have a special # meaning in URIs. -name=$(basename "$url" | @sed@ -e 's/%2b/+/g' -e 's/%3d/=/g' -e 's/%3f/\?/g') -if test -z "$name"; then echo "invalid url"; exit 1; fi +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 $hash; # If the hash was given, a file with that hash may already be in the # store. -if test -n "$expHash"; then - finalPath=$($binDir/nix-store --print-fixed-path "$hashType" "$expHash" "$name") - if ! $bindir/nix-store --check-validity "$finalPath" 2> /dev/null; then - finalPath= - fi - hash=$expHash -fi - - -mkTempDir() { - if test -n "$tmpPath"; then return; fi - local i=0 - while true; do - if test -z "$TMPDIR"; then TMPDIR=/tmp; fi - tmpPath=$TMPDIR/nix-prefetch-url-$$-$i - if mkdir "$tmpPath"; then break; fi - # !!! to bad we can't check for ENOENT in mkdir, so this check - # is slightly racy (it bombs out if somebody just removed - # $tmpPath...). - if ! test -e "$tmpPath"; then exit 1; fi - i=$((i + 1)) - done - trap removeTempDir EXIT SIGINT SIGQUIT +if (defined $expHash) { + $finalPath = makeFixedOutputPath(0, $hashType, $expHash, $name); + if (isValidPath($finalPath)) { $hash = $expHash; } else { $finalPath = undef; } } -removeTempDir() { - if test -n "$tmpPath"; then - rm -rf "$tmpPath" || true - fi -} - - -doDownload() { - @curl@ $cacheFlags --fail --location --max-redirs 20 --disable-epsv \ - --cookie-jar $tmpPath/cookies "$url" -o $tmpFile -} - - -# Hack to support the mirror:// scheme from Nixpkgs. -if test "${url:0:9}" = "mirror://"; then - if test -z "$NIXPKGS_ALL"; then - echo "Resolving mirror:// URLs requires Nixpkgs. Please point \$NIXPKGS_ALL at a Nixpkgs tree." >&2 - exit 1 - fi - - mkTempDir - nix-build "$NIXPKGS_ALL" -A resolveMirrorURLs --argstr url "$url" -o $tmpPath/urls > /dev/null - - expanded=($(cat $tmpPath/urls)) - if test "${#expanded[*]}" = 0; then - echo "$0: cannot resolve $url." >&2 - exit 1 - fi - - echo "$url expands to ${expanded[*]} (using ${expanded[0]})" >&2 - url="${expanded[0]}" -fi - - # 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 test -z "$finalPath"; then - - mkTempDir - tmpFile=$tmpPath/$name +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 $url. The caching of # the file *contents* is done in Nix store, where it can be # garbage-collected independently. - if test -n "$NIX_DOWNLOAD_CACHE"; then - echo -n "$url" > $tmpPath/url - urlHash=$($binDir/nix-hash --type sha256 --base32 --flat $tmpPath/url) - echo "$url" > "$NIX_DOWNLOAD_CACHE/$urlHash.url" - cachedHashFN="$NIX_DOWNLOAD_CACHE/$urlHash.$hashType" - cachedTimestampFN="$NIX_DOWNLOAD_CACHE/$urlHash.stamp" - cacheFlags="--remote-time" - if test -e "$cachedTimestampFN" -a -e "$cachedHashFN"; then - # Only download the file if it is newer than the cached version. - cacheFlags="$cacheFlags --time-cond $cachedTimestampFN" - fi - fi - + my ($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. - doDownload + 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 test -n "$NIX_DOWNLOAD_CACHE" -a ! -e $tmpFile; then + if (defined $cacheDir && ! -e $tmpFile) { # Curl didn't create $tmpFile, so apparently there's no newer # file on the server. - hash=$(cat $cachedHashFN) - finalPath=$($binDir/nix-store --print-fixed-path "$hashType" "$hash" "$name") - if ! $binDir/nix-store --check-validity "$finalPath" 2> /dev/null; then - echo "cached contents of \`$url' disappeared, redownloading..." >&2 - finalPath= - cacheFlags="--remote-time" - doDownload - fi - fi - - if test -z "$finalPath"; then - + $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 $finalPath) { + # Compute the hash. - hash=$($binDir/nix-hash --type "$hashType" $hashFormat --flat $tmpFile) - if ! test -n "$QUIET"; then echo "hash is $hash" >&2; fi - - if test -n "$NIX_DOWNLOAD_CACHE"; then - echo $hash > $cachedHashFN - touch -r $tmpFile $cachedTimestampFN - fi - + $hash = hashFile($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, $cachedTimestampFN) or die; + } + # Add the downloaded file to the Nix store. - finalPath=$($binDir/nix-store --add-fixed "$hashType" $tmpFile) - - if test -n "$expHash" -a "$expHash" != "$hash"; then - echo "hash mismatch for URL \`$url'" >&2 - exit 1 - fi - - fi -fi + $finalPath = addToStore($tmpFile, 0, $hashType); + } + die "$0: hash mismatch for ‘$url’\n" if defined $expHash && $expHash ne $hash; +} -if ! test -n "$QUIET"; then echo "path is $finalPath" >&2; fi - -echo $hash - -if test -n "$PRINT_PATH"; then - echo $finalPath -fi +print STDERR "path is ‘$finalPath’\n" unless $ENV{'QUIET'}; +print "$hash\n"; +print "$finalPath\n" if $ENV{'PRINT_PATH'}; |