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-rw-r--r--perl/lib/Nix/GeneratePatches.pm340
1 files changed, 0 insertions, 340 deletions
diff --git a/perl/lib/Nix/GeneratePatches.pm b/perl/lib/Nix/GeneratePatches.pm
deleted file mode 100644
index 612c8a3a15ba..000000000000
--- a/perl/lib/Nix/GeneratePatches.pm
+++ /dev/null
@@ -1,340 +0,0 @@
-package Nix::GeneratePatches;
-
-use strict;
-use File::Temp qw(tempdir);
-use File::stat;
-use Nix::Config;
-use Nix::Manifest;
-
-our @ISA = qw(Exporter);
-our @EXPORT = qw(generatePatches propagatePatches copyPatches);
-
-
-# Some patch generations options.
-
-# Max size of NAR archives to generate patches for.
-my $maxNarSize = $ENV{"NIX_MAX_NAR_SIZE"};
-$maxNarSize = 160 * 1024 * 1024 if !defined $maxNarSize;
-
-# If patch is bigger than this fraction of full archive, reject.
-my $maxPatchFraction = $ENV{"NIX_PATCH_FRACTION"};
-$maxPatchFraction = 0.60 if !defined $maxPatchFraction;
-
-my $timeLimit = $ENV{"NIX_BSDIFF_TIME_LIMIT"};
-$timeLimit = 180 if !defined $timeLimit;
-
-my $hashAlgo = "sha256";
-
-
-sub findOutputPaths {
-    my $narFiles = shift;
-
-    my %outPaths;
-    
-    foreach my $p (keys %{$narFiles}) {
-
-        # Ignore derivations.
-        next if ($p =~ /\.drv$/);
-        
-        # Ignore builders (too much ambiguity -- they're all called
-        # `builder.sh').
-        next if ($p =~ /\.sh$/);
-        next if ($p =~ /\.patch$/);
-        
-        # Don't bother including tar files etc.
-        next if ($p =~ /\.tar$/ || $p =~ /\.tar\.(gz|bz2|Z|lzma|xz)$/ || $p =~ /\.zip$/ || $p =~ /\.bin$/ || $p =~ /\.tgz$/ || $p =~ /\.rpm$/ || $p =~ /cvs-export$/ || $p =~ /fetchhg$/);
-
-        $outPaths{$p} = 1;
-    }
-
-    return %outPaths;
-}
-
-
-sub getNameVersion {
-    my $p = shift;
-    $p =~ /\/[0-9a-z]+((?:-[a-zA-Z][^\/-]*)+)([^\/]*)$/;
-    my $name = $1;
-    my $version = $2;
-    return undef unless defined $name && defined $version;
-    $name =~ s/^-//;
-    $version =~ s/^-//;
-    return ($name, $version);
-}
-
-
-# A quick hack to get a measure of the `distance' between two
-# versions: it's just the position of the first character that differs
-# (or 999 if they are the same).
-sub versionDiff {
-    my $s = shift;
-    my $t = shift;
-    my $i;
-    return 999 if $s eq $t;
-    for ($i = 0; $i < length $s; $i++) {
-        return $i if $i >= length $t or
-            substr($s, $i, 1) ne substr($t, $i, 1);
-    }
-    return $i;
-}
-
-
-sub getNarBz2 {
-    my $narPath = shift;
-    my $narFiles = shift;
-    my $storePath = shift;
-    
-    my $narFileList = $$narFiles{$storePath};
-    die "missing path $storePath" unless defined $narFileList;
-
-    my $narFile = @{$narFileList}[0];
-    die unless defined $narFile;
-
-    $narFile->{url} =~ /\/([^\/]+)$/;
-    die unless defined $1;
-    return "$narPath/$1";
-}
-
-
-sub containsPatch {
-    my $patches = shift;
-    my $storePath = shift;
-    my $basePath = shift;
-    my $patchList = $$patches{$storePath};
-    return 0 if !defined $patchList;
-    my $found = 0;
-    foreach my $patch (@{$patchList}) {
-        # !!! baseHash might differ
-        return 1 if $patch->{basePath} eq $basePath;
-    }
-    return 0;
-}
-
-
-sub generatePatches {
-    my ($srcNarFiles, $dstNarFiles, $srcPatches, $dstPatches, $narPath, $patchesPath, $patchesURL, $tmpDir) = @_;
-
-    my %srcOutPaths = findOutputPaths $srcNarFiles;
-    my %dstOutPaths = findOutputPaths $dstNarFiles;
-
-    # For each output path in the destination, see if we need to / can
-    # create a patch.
-
-    print STDERR "creating patches...\n";
-
-    foreach my $p (keys %dstOutPaths) {
-
-        # If exactly the same path already exists in the source, skip it.
-        next if defined $srcOutPaths{$p};
-    
-        print "  $p\n";
-
-        # If not, then we should find the paths in the source that are
-        # `most' likely to be present on a system that wants to
-        # install this path.
-
-        (my $name, my $version) = getNameVersion $p;
-        next unless defined $name && defined $version;
-
-        my @closest = ();
-        my $closestVersion;
-        my $minDist = -1; # actually, larger means closer
-
-        # Find all source paths with the same name.
-
-        foreach my $q (keys %srcOutPaths) {
-            (my $name2, my $version2) = getNameVersion $q;
-            next unless defined $name2 && defined $version2;
-
-            if ($name eq $name2) {
-
-                my $srcSystem = @{$$dstNarFiles{$p}}[0]->{system};
-                my $dstSystem = @{$$srcNarFiles{$q}}[0]->{system};
-                if (defined $srcSystem && defined $dstSystem && $srcSystem ne $dstSystem) {
-                    print "    SKIPPING $q due to different systems ($srcSystem vs. $dstSystem)\n";
-                    next;
-                }
-
-                # If the sizes differ too much, then skip.  This
-                # disambiguates between, e.g., a real component and a
-                # wrapper component (cf. Firefox in Nixpkgs).
-                my $srcSize = @{$$srcNarFiles{$q}}[0]->{size};
-                my $dstSize = @{$$dstNarFiles{$p}}[0]->{size};
-                my $ratio = $srcSize / $dstSize;
-                $ratio = 1 / $ratio if $ratio < 1;
-                # print "  SIZE $srcSize $dstSize $ratio $q\n";
-
-                if ($ratio >= 3) {
-                    print "    SKIPPING $q due to size ratio $ratio ($srcSize vs. $dstSize)\n";
-                    next;
-                }
-
-                # If there are multiple matching names, include the
-                # ones with the closest version numbers.
-                my $dist = versionDiff $version, $version2;
-                if ($dist > $minDist) {
-                    $minDist = $dist;
-                    @closest = ($q);
-                    $closestVersion = $version2;
-                } elsif ($dist == $minDist) {
-                    push @closest, $q;
-                }
-            }
-        }
-
-        if (scalar(@closest) == 0) {
-            print "    NO BASE: $p\n";
-            next;
-        }
-
-        foreach my $closest (@closest) {
-
-            # Generate a patch between $closest and $p.
-            print STDERR "  $p <- $closest\n";
-
-            # If the patch already exists, skip it.
-            if (containsPatch($srcPatches, $p, $closest) ||
-                containsPatch($dstPatches, $p, $closest))
-            {
-                print "    skipping, already exists\n";
-                next;
-            }
-
-            my $srcNarBz2 = getNarBz2 $narPath, $srcNarFiles, $closest;
-            my $dstNarBz2 = getNarBz2 $narPath, $dstNarFiles, $p;
-
-            if (! -f $srcNarBz2) {
-                warn "patch source archive $srcNarBz2 is missing\n";
-                next;
-            }
-
-            system("$Nix::Config::bzip2 -d < $srcNarBz2 > $tmpDir/A") == 0
-                or die "cannot unpack $srcNarBz2";
-
-            if (stat("$tmpDir/A")->size >= $maxNarSize) {
-                print "    skipping, source is too large\n";
-                next;
-            }
-        
-            system("$Nix::Config::bzip2 -d < $dstNarBz2 > $tmpDir/B") == 0
-                or die "cannot unpack $dstNarBz2";
-
-            if (stat("$tmpDir/B")->size >= $maxNarSize) {
-                print "    skipping, destination is too large\n";
-                next;
-            }
-        
-            my $time1 = time();
-            my $res = system("ulimit -t $timeLimit; $Nix::Config::libexecDir/nix/bsdiff $tmpDir/A $tmpDir/B $tmpDir/DIFF");
-            my $time2 = time();
-            if ($res) {
-                warn "binary diff computation aborted after ", $time2 - $time1, " seconds\n";
-                next;
-            }
-
-            my $baseHash = `$Nix::Config::binDir/nix-hash --flat --type $hashAlgo --base32 $tmpDir/A` or die;
-            chomp $baseHash;
-
-            my $narHash = `$Nix::Config::binDir/nix-hash --flat --type $hashAlgo --base32 $tmpDir/B` or die;
-            chomp $narHash;
-
-            my $narDiffHash = `$Nix::Config::binDir/nix-hash --flat --type $hashAlgo --base32 $tmpDir/DIFF` or die;
-            chomp $narDiffHash;
-
-            my $narDiffSize = stat("$tmpDir/DIFF")->size;
-            my $dstNarBz2Size = stat($dstNarBz2)->size;
-
-            print "    size $narDiffSize; full size $dstNarBz2Size; ", $time2 - $time1, " seconds\n";
-        
-            if ($narDiffSize >= $dstNarBz2Size) {
-                print "    rejecting; patch bigger than full archive\n";
-                next;
-            }
-    
-            if ($narDiffSize / $dstNarBz2Size >= $maxPatchFraction) {
-                print "    rejecting; patch too large relative to full archive\n";
-                next;
-            }
-    
-            my $finalName = "$narDiffHash.nar-bsdiff";
-
-            if (-e "$patchesPath/$finalName") {
-                print "    not copying, already exists\n";
-            }
-
-            else {
-                system("cp '$tmpDir/DIFF' '$patchesPath/$finalName.tmp'") == 0
-                    or die "cannot copy diff";
-                rename("$patchesPath/$finalName.tmp", "$patchesPath/$finalName")
-                    or die "cannot rename $patchesPath/$finalName.tmp";
-            }
-        
-            # Add the patch to the manifest.
-            addPatch $dstPatches, $p,
-                { url => "$patchesURL/$finalName", hash => "$hashAlgo:$narDiffHash"
-                , size => $narDiffSize, basePath => $closest, baseHash => "$hashAlgo:$baseHash"
-                , narHash => "$hashAlgo:$narHash", patchType => "nar-bsdiff"
-                };
-        }
-    }
-}
-
-
-# Propagate useful patches from $srcPatches to $dstPatches.  A patch
-# is useful if it produces either paths in the $dstNarFiles or paths
-# that can be used as the base for other useful patches.
-sub propagatePatches {
-    my ($srcPatches, $dstNarFiles, $dstPatches) = @_;
-
-    print STDERR "propagating patches...\n";
-
-    my $changed;
-    do {
-        # !!! we repeat this to reach the transitive closure; inefficient
-        $changed = 0;
-
-        print STDERR "loop\n";
-
-        my %dstBasePaths;
-        foreach my $q (keys %{$dstPatches}) {
-            foreach my $patch (@{$$dstPatches{$q}}) {
-                $dstBasePaths{$patch->{basePath}} = 1;
-            }
-        }
-
-        foreach my $p (keys %{$srcPatches}) {
-            my $patchList = $$srcPatches{$p};
-
-            my $include = 0;
-
-            # Is path $p included in the destination?  If so, include
-            # patches that produce it.
-            $include = 1 if defined $$dstNarFiles{$p};
-
-            # Is path $p a path that serves as a base for paths in the
-            # destination?  If so, include patches that produce it.
-            # !!! check baseHash
-            $include = 1 if defined $dstBasePaths{$p};
-
-            if ($include) {
-                foreach my $patch (@{$patchList}) {
-                    $changed = 1 if addPatch $dstPatches, $p, $patch;
-                }
-            }
-        
-        }
-    
-    } while $changed;
-}
-
-
-# Add all new patches in $srcPatches to $dstPatches.
-sub copyPatches {
-    my ($srcPatches, $dstPatches) = @_;
-    foreach my $p (keys %{$srcPatches}) {
-        addPatch $dstPatches, $p, $_ foreach @{$$srcPatches{$p}};
-    }
-}
-
-
-return 1;