1 files changed, 40 insertions, 0 deletions
diff --git a/lib/systems/default.nix b/lib/systems/default.nix
index 0b3475fefb9ce..25df5e1740697 100644
--- a/lib/systems/default.nix
+++ b/lib/systems/default.nix
@@ -66,6 +66,46 @@ rec {
          # uname -r
          release = null;
       };
+
+      qemuArch =
+        if final.isArm then "arm"
+        else if final.isx86_64 then "x86_64"
+        else if final.isx86 then "i386"
+        else {
+          "powerpc" = "ppc";
+          "powerpc64" = "ppc64";
+          "powerpc64le" = "ppc64";
+          "mips64" = "mips";
+          "mipsel64" = "mipsel";
+        }.${final.parsed.cpu.name} or final.parsed.cpu.name;
+
+      emulator = pkgs: let
+        qemu-user = pkgs.qemu.override {
+          smartcardSupport = false;
+          spiceSupport = false;
+          openGLSupport = false;
+          virglSupport = false;
+          vncSupport = false;
+          gtkSupport = false;
+          sdlSupport = false;
+          pulseSupport = false;
+          smbdSupport = false;
+          seccompSupport = false;
+          hostCpuTargets = ["${final.qemuArch}-linux-user"];
+        };
+        wine-name = "wine${toString final.parsed.cpu.bits}";
+        wine = (pkgs.winePackagesFor wine-name).minimal;
+      in
+        if final.parsed.kernel.name == pkgs.stdenv.hostPlatform.parsed.kernel.name &&
+           (final.parsed.cpu.name == pkgs.stdenv.hostPlatform.parsed.cpu.name ||
+            (final.platform.isi686 && pkgs.stdenv.hostPlatform.isx86_64))
+        then pkgs.runtimeShell
+        else if final.isWindows
+        then "${wine}/bin/${wine-name}"
+        else if final.isLinux && pkgs.stdenv.hostPlatform.isLinux
+        then "${qemu-user}/bin/qemu-${final.qemuArch}"
+        else throw "Don't know how to run ${final.config} executables.";
+
     } // mapAttrs (n: v: v final.parsed) inspect.predicates
       // args;
   in assert final.useAndroidPrebuilt -> final.isAndroid;