1
0
Fork 0
forked from lix-project/lix
lix/corepkgs/buildenv.pl
2014-08-20 18:03:48 +02:00

169 lines
4.9 KiB
Perl
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

use strict;
use Cwd;
use IO::Handle;
use utf8;
STDOUT->autoflush(1);
my $out = $ENV{"out"};
mkdir "$out", 0755 || die "error creating $out";
my $symlinks = 0;
my %priorities;
# For each activated package, create symlinks.
sub createLinks {
my $srcDir = shift;
my $dstDir = shift;
my $priority = shift;
my @srcFiles = glob("$srcDir/*");
foreach my $srcFile (@srcFiles) {
my $baseName = $srcFile;
$baseName =~ s/^.*\///g; # strip directory
my $dstFile = "$dstDir/$baseName";
# The files below are special-cased so that they don't show up
# in user profiles, either because they are useless, or
# because they would cause pointless collisions (e.g., each
# Python package brings its own
# `$out/lib/pythonX.Y/site-packages/easy-install.pth'.)
# Urgh, hacky...
if ($srcFile =~ /\/propagated-build-inputs$/ ||
$srcFile =~ /\/nix-support$/ ||
$srcFile =~ /\/perllocal.pod$/ ||
$srcFile =~ /\/info\/dir$/ ||
$srcFile =~ /\/log$/)
{
# Do nothing.
}
elsif (-d $srcFile) {
lstat $dstFile;
if (-d _) {
createLinks($srcFile, $dstFile, $priority);
}
elsif (-l _) {
my $target = readlink $dstFile or die;
if (!-d $target) {
die "collision between directory $srcFile and non-directory $target";
}
unlink $dstFile or die "error unlinking $dstFile: $!";
mkdir $dstFile, 0755 ||
die "error creating directory $dstFile: $!";
createLinks($target, $dstFile, $priorities{$dstFile});
createLinks($srcFile, $dstFile, $priority);
}
else {
symlink($srcFile, $dstFile) ||
die "error creating link $dstFile: $!";
$priorities{$dstFile} = $priority;
$symlinks++;
}
}
else {
if (-l $dstFile) {
my $target = readlink $dstFile;
my $prevPriority = $priorities{$dstFile};
die("collision between $srcFile and $target; " .
"use nix-env --set-flag priority NUMBER PKGNAME " .
"to change the priority of one of the conflicting packages\n")
if $prevPriority == $priority;
next if $prevPriority < $priority;
unlink $dstFile or die;
}
symlink($srcFile, $dstFile) ||
die "error creating link $dstFile: $!";
$priorities{$dstFile} = $priority;
$symlinks++;
}
}
}
my %done;
my %postponed;
sub addPkg;
sub addPkg {
my $pkgDir = shift;
my $priority = shift;
return if (defined $done{$pkgDir});
$done{$pkgDir} = 1;
# print "symlinking $pkgDir\n";
createLinks("$pkgDir", "$out", $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};
}
}
}
# Convert the stuff we get from the environment back into a coherent
# data type.
my @pkgs;
my @derivations = split ' ', $ENV{"derivations"};
while (scalar @derivations) {
my $active = shift @derivations;
my $priority = shift @derivations;
my $outputs = shift @derivations;
for (my $n = 0; $n < $outputs; $n++) {
my $path = shift @derivations;
push @pkgs,
{ path => $path
, active => $active ne "false"
, priority => int($priority) };
}
}
# Symlink to the packages that have been installed explicitly by the
# user. Process in priority order to reduce unnecessary
# symlink/unlink steps.
@pkgs = sort { $a->{priority} <=> $b->{priority} || $a->{path} cmp $b->{path} } @pkgs;
foreach my $pkg (@pkgs) {
#print $pkg, " ", $pkgs{$pkg}->{priority}, "\n";
addPkg($pkg->{path}, $pkg->{priority}) if $pkg->{active};
}
# Symlink to the packages that have been "propagated" by packages
# installed by the user (i.e., package X declares that it want 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, $priorityCounter++);
}
}
print STDERR "created $symlinks symlinks in user environment\n";
symlink($ENV{"manifest"}, "$out/manifest.nix") or die "cannot create manifest";