From a4f0365b2dfc95b60c42a702937fc801dcc8d81b Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Wed, 17 Nov 2010 17:41:59 +0000 Subject: [PATCH] * When checking whether a patch is applicable, for efficiency, use `nix-store -q --hash' to get the hash of the base path rather than `nix-hash'. However, only do this for estimating the size of a download, not for the actual substitution, because sometimes the contents of store paths are modified (which they shouldn't, of course). --- scripts/download-using-manifests.pl.in | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/scripts/download-using-manifests.pl.in b/scripts/download-using-manifests.pl.in index 7147090c4..c31a294e8 100644 --- a/scripts/download-using-manifests.pl.in +++ b/scripts/download-using-manifests.pl.in @@ -51,6 +51,7 @@ sub parseHash { # given path. sub computeSmallestDownload { my $targetPath = shift; + my $fast = shift; # Build a graph of all store paths that might contribute to the # construction of $targetPath, and the special node "start". The @@ -110,8 +111,11 @@ sub computeSmallestDownload { my ($baseHashAlgo, $baseHash) = parseHash $patch->{baseHash}; my $format = "--base32"; $format = "" if $baseHashAlgo eq "md5"; - my $hash = `$binDir/nix-hash --type '$baseHashAlgo' $format "$patch->{basePath}"`; + my $hash = $fast && $baseHashAlgo eq "sha256" + ? `$binDir/nix-store -q --hash "$patch->{basePath}"` + : `$binDir/nix-hash --type '$baseHashAlgo' $format "$patch->{basePath}"`; chomp $hash; + $hash =~ s/.*://; next if $hash ne $baseHash; } push @queue, $patch->{basePath}; @@ -203,7 +207,7 @@ if ($ARGV[0] eq "--query") { print scalar @references, "\n"; print "$_\n" foreach @references; - my @path = computeSmallestDownload $storePath; + my @path = computeSmallestDownload $storePath, 1; my $downloadSize = 0; while (scalar @path > 0) { @@ -269,7 +273,7 @@ foreach my $localPath (@{$localPathList}) { # Compute the shortest path. -my @path = computeSmallestDownload $targetPath; +my @path = computeSmallestDownload $targetPath, 0; die "don't know how to produce $targetPath\n" if scalar @path == 0;