1 files changed, 95 insertions, 0 deletions
diff --git a/lib/module.h b/lib/module.h
new file mode 100644
index 0000000..cd2be47
--- /dev/null
+++ b/lib/module.h
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: ISC
+/*
+ * Copyright (c) 2015-16  David Lamparter, for NetDEF, Inc.
+ */
+
+#ifndef _FRR_MODULE_H
+#define _FRR_MODULE_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "compiler.h"
+#include "xref.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct frrmod_runtime;
+
+struct frrmod_info {
+	/* single-line few-word title */
+	const char *name;
+	/* human-readable version number, should not contain spaces */
+	const char *version;
+	/* one-paragraph description */
+	const char *description;
+
+	int (*init)(void);
+};
+
+/* primary entry point structure to be present in loadable module under
+ * "_frrmod_this_module" dlsym() name
+ *
+ * note space for future extensions is reserved below, so other modules
+ * (e.g. memory management, hooks) can add fields
+ *
+ * const members/info are in frrmod_info.
+ */
+struct frrmod_runtime {
+	struct frrmod_runtime *next;
+
+	const struct frrmod_info *info;
+	void *dl_handle;
+	bool finished_loading;
+
+	char *load_name;
+	char *load_args;
+};
+
+/* space-reserving foo */
+struct _frrmod_runtime_size {
+	struct frrmod_runtime r;
+	/* this will barf if frrmod_runtime exceeds 1024 bytes ... */
+	uint8_t space[1024 - sizeof(struct frrmod_runtime)];
+};
+union _frrmod_runtime_u {
+	struct frrmod_runtime r;
+	struct _frrmod_runtime_size s;
+};
+
+extern union _frrmod_runtime_u _frrmod_this_module;
+#define THIS_MODULE (&_frrmod_this_module.r)
+
+#define FRR_COREMOD_SETUP(...)                                                 \
+	static const struct frrmod_info _frrmod_info = {__VA_ARGS__};          \
+	DSO_LOCAL union _frrmod_runtime_u _frrmod_this_module = {{             \
+		NULL,                                                          \
+		&_frrmod_info,                                                 \
+	}};                                                                    \
+	XREF_SETUP();                                                          \
+	MACRO_REQUIRE_SEMICOLON() /* end */
+
+#define FRR_MODULE_SETUP(...)                                                  \
+	FRR_COREMOD_SETUP(__VA_ARGS__);                                        \
+	DSO_SELF struct frrmod_runtime *frr_module = &_frrmod_this_module.r;   \
+	MACRO_REQUIRE_SEMICOLON() /* end */
+
+extern struct frrmod_runtime *frrmod_list;
+
+extern void frrmod_init(struct frrmod_runtime *modinfo);
+extern struct frrmod_runtime *frrmod_load(const char *spec, const char *dir,
+					  void (*pFerrlog)(const void *,
+							   const char *),
+					  const void *pErrlogCookie);
+#if 0
+/* not implemented yet */
+extern void frrmod_unload(struct frrmod_runtime *module);
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _FRR_MODULE_H */