Add rejectSystemFeatures to derivations

Author: RossComputerGuy

src/libstore/parsed-derivations.cc

@@ -98,6 +98,15 @@ StringSet ParsedDerivation::getRequiredSystemFeatures() const
     return res;
 }
 
+StringSet ParsedDerivation::getRejectSystemFeatures() const
+{
+    // FIXME: cache this?
+    StringSet res;
+    for (auto & i : getStringsAttr("rejectSystemFeatures").value_or(Strings()))
+        res.insert(i);
+    return res;
+}
+
 bool ParsedDerivation::canBuildLocally(Store & localStore) const
 {
     if (drv.platform != settings.thisSystem.get()
@@ -112,6 +121,9 @@ bool ParsedDerivation::canBuildLocally(Store & localStore) const
     for (auto & feature : getRequiredSystemFeatures())
         if (!localStore.systemFeatures.get().count(feature)) return false;
 
+    for (auto & feature : getRejectSystemFeatures())
+        if (localStore.systemFeatures.get().count(feature)) return false;
+
     return true;
 }
 

src/libstore/parsed-derivations.hh

@@ -33,6 +33,8 @@ public:
 
     StringSet getRequiredSystemFeatures() const;
 
+    StringSet getRejectSystemFeatures() const;
+
     bool canBuildLocally(Store & localStore) const;
 
     bool willBuildLocally(Store & localStore) const;

src/libstore/unix/build/local-derivation-goal.cc

@@ -532,9 +532,10 @@ void LocalDerivationGoal::startBuilder()
 
     /* Right platform? */
     if (!parsedDrv->canBuildLocally(worker.store))
-        throw Error("a '%s' with features {%s} is required to build '%s', but I am a '%s' with features {%s}",
+        throw Error("a '%s' with features {%s} & not {%s} is required to build '%s', but I am a '%s' with features {%s}",
             drv->platform,
             concatStringsSep(", ", parsedDrv->getRequiredSystemFeatures()),
+            concatStringsSep(", ", parsedDrv->getRejectSystemFeatures()),
             worker.store.printStorePath(drvPath),
             settings.thisSystem,
             concatStringsSep<StringSet>(", ", worker.store.systemFeatures));