Pass configuration settings to the substituters

Previously substituters could read nix.conf themselves, but this
didn't take --option flags into account.

1 files changed, 9 insertions, 1 deletions

diff --git a/perl/lib/Nix/Config.pm.in b/perl/lib/Nix/Config.pm.in
index ed197821e89f..8c902ab6edc5 100644
--- a/perl/lib/Nix/Config.pm.in
+++ b/perl/lib/Nix/Config.pm.in
@@ -19,9 +19,17 @@ $useBindings = "@perlbindings@" eq "yes";
 %config = ();
 
 sub readConfig {
+    if (defined $ENV{'_NIX_OPTIONS'}) {
+        foreach my $s (split '\n', $ENV{'_NIX_OPTIONS'}) {
+            my ($n, $v) = split '=', $s, 2;
+            $config{$n} = $v;
+        }
+        return;
+    }
+
     my $config = "$confDir/nix.conf";
     return unless -f $config;
-    
+
     open CONFIG, "<$config" or die "cannot open `$config'";
     while (<CONFIG>) {
         /^\s*([\w|-]+)\s*=\s*(.*)$/ or next;