1 files changed, 31 insertions, 0 deletions
diff --git a/third_party/nix/src/nix/show-config.cc b/third_party/nix/src/nix/show-config.cc
new file mode 100644
index 0000000000..fd92e481e8
--- /dev/null
+++ b/third_party/nix/src/nix/show-config.cc
@@ -0,0 +1,31 @@
+#include "libmain/common-args.hh"
+#include "libmain/shared.hh"
+#include "libstore/store-api.hh"
+#include "libutil/json.hh"
+#include "nix/command.hh"
+
+namespace nix {
+struct CmdShowConfig final : Command, MixJSON {
+  CmdShowConfig() = default;
+
+  std::string name() override { return "show-config"; }
+
+  std::string description() override { return "show the Nix configuration"; }
+
+  void run() override {
+    if (json) {
+      // FIXME: use appropriate JSON types (bool, ints, etc).
+      JSONObject jsonObj(std::cout);
+      globalConfig.toJSON(jsonObj);
+    } else {
+      std::map<std::string, Config::SettingInfo> settings;
+      globalConfig.getSettings(settings);
+      for (auto& s : settings) {
+        std::cout << s.first + " = " + s.second.value + "\n";
+      }
+    }
+  }
+};
+}  // namespace nix
+
+static nix::RegisterCommand r1(nix::make_ref<nix::CmdShowConfig>());