diff options
Diffstat (limited to 'scripts/nix-prefetch-url.in')
| -rw-r--r-- | scripts/nix-prefetch-url.in | 63 |
1 files changed, 31 insertions, 32 deletions
diff --git a/scripts/nix-prefetch-url.in b/scripts/nix-prefetch-url.in index 615383833..5f6ea4c0d 100644 --- a/scripts/nix-prefetch-url.in +++ b/scripts/nix-prefetch-url.in @@ -1,7 +1,7 @@ #! @shell@ -e url=$1 -hash=$2 +expHash=$2 hashType=$NIX_HASH_ALGO if test -z "$hashType"; then @@ -14,55 +14,54 @@ if test "$hashType" != "md5"; then fi if test -z "$url"; then - echo "syntax: nix-prefetch-url URL" >&2 + echo "syntax: nix-prefetch-url URL [EXPECTED-HASH]" >&2 exit 1 fi -# Determine the hash, unless it was given. -if test -z "$hash"; then +name=$(basename "$url") +if test -z "$name"; then echo "invalid url"; exit 1; fi - # !!! race - tmpPath1=@storedir@/nix-prefetch-url-$$ - # Test whether we have write permission in the store. If not, - # fetch to /tmp and don't copy to the store. This is a hack to - # make this script at least work somewhat in setuid installations. - if ! touch $tmpPath1 2> /dev/null; then - echo "(cannot write to the store, result won't be cached)" >&2 - dummyMode=1 - tmpPath1=/tmp/nix-prefetch-url-$$ # !!! security? +# 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=$expHash +fi + + +# If we don't know the hash or a file with that hash doesn't exist, +# download the file and add it to the store. +if test -z "$finalPath"; then + + tmpPath=/tmp/nix-prefetch-url-$$ # !!! security? + tmpFile=$tmpPath/$name + mkdir $tmpPath # Perform the download. - @curl@ --fail --location --max-redirs 20 "$url" > $tmpPath1 + @curl@ --fail --location --max-redirs 20 "$url" > $tmpFile # Compute the hash. - hash=$(@bindir@/nix-hash --type "$hashType" $hashFormat --flat $tmpPath1) + hash=$(@bindir@/nix-hash --type "$hashType" $hashFormat --flat $tmpFile) if ! test -n "$QUIET"; then echo "hash is $hash" >&2; fi - # Rename it so that the fetchurl builder can find it. - if test "$dummyMode" != 1; then - tmpPath2=@storedir@/nix-prefetch-url-$hash - test -e $tmpPath2 || mv $tmpPath1 $tmpPath2 # !!! race - fi + # Add the downloaded file to the Nix store. + finalPath=$(@bindir@/nix-store --add-fixed "$hashType" $tmpFile) + if test -n "$tmpPath"; then rm -rf $tmpPath || true; fi + + if test -n "$expHash" -a "$expHash" != "$hash"; then + echo "hash mismatch for URL \`$url'" + exit 1 + fi fi -# Create a Nix expression that does a fetchurl. -storeExpr=$( \ - echo "(import @datadir@/nix/corepkgs/fetchurl) \ - {url = $url; outputHashAlgo = \"$hashType\"; outputHash = \"$hash\"; system = \"@system@\";}" \ - | @bindir@/nix-instantiate -) -# Realise it. -finalPath=$(@bindir@/nix-store -r $storeExpr) - if ! test -n "$QUIET"; then echo "path is $finalPath" >&2; fi -if test -n "$tmpPath1" -o -n "$tmpPath2"; then - rm -rf $tmpPath1 $tmpPath2 || true -fi - echo $hash if test -n "$PRINT_PATH"; then |