nixpkgs/pkgs/build-support/buildenv/builder.pl

169 lines
4.6 KiB
Perl
Raw Normal View History

#! @perl@ -w
use strict;
use Cwd 'abs_path';
use IO::Handle;
use File::Path;
use File::Basename;
use JSON::PP;
STDOUT->autoflush(1);
my $out = $ENV{"out"};
my @pathsToLink = split ' ', $ENV{"pathsToLink"};
sub isInPathsToLink {
my $path = shift;
$path = "/" if $path eq "";
foreach my $elem (@pathsToLink) {
return 1 if
$elem eq "/" ||
(substr($path, 0, length($elem)) eq $elem
&& (($path eq $elem) || (substr($path, length($elem), 1) eq "/")));
}
return 0;
}
# For each activated package, determine what symlinks to create.
my %symlinks;
for my $p (@pathsToLink) {
$p = "" if $p eq "/";
$symlinks{$p} = ["", 0];
}
sub findFiles;
sub findFilesInDir {
my ($relName, $target, $ignoreCollisions, $priority) = @_;
opendir DIR, "$target" or die "cannot open `$target': $!";
my @names = readdir DIR or die;
closedir DIR;
foreach my $name (@names) {
next if $name eq "." || $name eq "..";
findFiles("$relName/$name", "$target/$name", $name, $ignoreCollisions, $priority);
}
}
sub findFiles {
my ($relName, $target, $baseName, $ignoreCollisions, $priority) = @_;
# Urgh, hacky...
return if
$relName eq "/propagated-build-inputs" ||
$relName eq "/nix-support" ||
$relName =~ /info\/dir/ ||
( $relName =~ /^\/share\/mime\// && !( $relName =~ /^\/share\/mime\/packages/ ) ) ||
$baseName eq "perllocal.pod" ||
$baseName eq "log";
my ($oldTarget, $oldPriority) = @{$symlinks{$relName} // [undef, undef]};
# If target doesn't exist, create it. If it already exists as a
# symlink to a file (not a directory) in a lower-priority package,
# overwrite it.
if (!defined $oldTarget || ($priority < $oldPriority && ($oldTarget ne "" && ! -d $oldTarget))) {
$symlinks{$relName} = [$target, $priority];
return;
}
# If target already exists as a symlink to a file (not a
# directory) in a higher-priority package, skip.
if (defined $oldTarget && $priority > $oldPriority && $oldTarget ne "" && ! -d $oldTarget) {
return;
}
unless (-d $target && ($oldTarget eq "" || -d $oldTarget)) {
if ($ignoreCollisions) {
warn "collision between `$target' and `$oldTarget'\n" if $ignoreCollisions == 1;
return;
} else {
die "collision between `$target' and `$oldTarget'\n";
}
}
findFilesInDir($relName, $oldTarget, $ignoreCollisions, $oldPriority) unless $oldTarget eq "";
findFilesInDir($relName, $target, $ignoreCollisions, $priority);
$symlinks{$relName} = ["", $priority]; # denotes directory
}
my %done;
my %postponed;
sub addPkg {
my ($pkgDir, $ignoreCollisions, $priority) = @_;
return if (defined $done{$pkgDir});
$done{$pkgDir} = 1;
findFiles("", $pkgDir, "", $ignoreCollisions, $priority);
my $propagatedFN = "$pkgDir/nix-support/propagated-user-env-packages";
if (-e $propagatedFN) {
open PROP, "<$propagatedFN" or die;
my $propagated = <PROP>;
close PROP;
my @propagated = split ' ', $propagated;
foreach my $p (@propagated) {
$postponed{$p} = 1 unless defined $done{$p};
}
}
}
# Symlink to the packages that have been installed explicitly by the
# user.
for my $pkg (@{decode_json $ENV{"pkgs"}}) {
for my $path (@{$pkg->{paths}}) {
addPkg($path, $ENV{"ignoreCollisions"} eq "1", $pkg->{priority}) if -e $path;
}
}
# Symlink to the packages that have been "propagated" by packages
# installed by the user (i.e., package X declares that it wants Y
# installed as well). We do these later because they have a lower
# priority in case of collisions.
my $priorityCounter = 1000; # don't care about collisions
while (scalar(keys %postponed) > 0) {
my @pkgDirs = keys %postponed;
%postponed = ();
foreach my $pkgDir (sort @pkgDirs) {
addPkg($pkgDir, 2, $priorityCounter++);
}
}
# Create the symlinks.
my $nrLinks = 0;
foreach my $relName (sort keys %symlinks) {
my ($target, $priority) = @{$symlinks{$relName}};
my $abs = "$out/$relName";
next unless isInPathsToLink $relName;
if ($target eq "") {
#print "creating directory $relName\n";
mkpath $abs or die "cannot create directory `$abs': $!";
} else {
#print "creating symlink $relName to $target\n";
symlink $target, $abs ||
die "error creating link `$abs': $!";
$nrLinks++;
}
}
print STDERR "created $nrLinks symlinks in user environment\n";
my $manifest = $ENV{"manifest"};
if ($manifest) {
symlink($manifest, "$out/manifest") or die "cannot create manifest";
}