Add nix-flake-c, nix_flake_init_global, nix_flake_settings_new

src/libflake-c/nix_api_flake.h

@@ -0,0 +1,46 @@
+#ifndef NIX_API_FLAKE_H
+#define NIX_API_FLAKE_H
+/** @defgroup libflake libflake
+ * @brief Bindings to the Nix Flakes library
+ *
+ * @{
+ */
+/** @file
+ * @brief Main entry for the libflake C bindings
+ */
+
+#include "nix_api_store.h"
+#include "nix_api_util.h"
+#include "nix_api_expr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+// cffi start
+
+typedef struct nix_flake_settings nix_flake_settings;
+
+// Function prototypes
+/**
+ * Create a nix_flake_settings initialized with default values.
+ * @param[out] context Optional, stores error information
+ * @return A new nix_flake_settings or NULL on failure.
+ * @see nix_flake_settings_free
+ */
+nix_flake_settings * nix_flake_settings_new(nix_c_context * context);
+
+/**
+ * @brief Release the resources associated with a nix_flake_settings.
+ */
+void nix_flake_settings_free(nix_flake_settings * settings);
+
+/**
+ * @brief Register Flakes support process-wide.
+ */
+nix_err nix_flake_init_global(nix_c_context * context, nix_flake_settings * settings);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif