1 files changed, 133 insertions, 0 deletions
diff --git a/lib/frrscript.c b/lib/frrscript.c
new file mode 100644
index 0000000000..9b27ca7459
--- /dev/null
+++ b/lib/frrscript.c
@@ -0,0 +1,133 @@
+/* Scripting foo
+ * Copyright (C) 2020  NVIDIA Corporation
+ * Quentin Young
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <zebra.h>
+
+#include "frrscript.h"
+#include "memory.h"
+#include "hash.h"
+#include "log.h"
+
+#include "frrlua.h"
+
+/* Type encoders */
+
+struct encoder {
+	char *typename;
+	int (*encoder)(struct lua_State *, const void *);
+};
+
+struct hash *encoder_hash;
+
+static unsigned int encoder_hash_key(const void *data)
+{
+	const struct encoder *e = data;
+
+	return string_hash_make(e->typename);
+}
+
+static bool encoder_hash_cmp(const void *d1, const void *d2)
+{
+	return !strcmp(d1, d2);
+}
+
+static void *encoder_alloc(void *arg)
+{
+	struct encoder *tmp = arg;
+
+	struct encoder *e = XCALLOC(MTYPE_TMP, sizeof(struct encoder));
+	e->typename = XSTRDUP(MTYPE_TMP, tmp->typename);
+
+	return e;
+}
+
+#if 0
+static void encoder_free(struct encoder *e)
+{
+	XFREE(MTYPE_TMP, e->typename);
+	XFREE(MTYPE_TMP, e);
+}
+#endif
+
+/* Generic script APIs */
+
+int frrscript_lua_call(struct frrscript *fs, ...)
+{
+	/* Process arguments according to argspec in fs */
+	/* ... */
+
+	int ret = lua_pcall(fs->L, 0, 0, 0);
+
+	/* Process stack result according to argspec in fs */
+	/* ... */
+
+	/* LUA_OK is 0, so we can just return lua_pcall's result directly */
+	return ret;
+}
+
+void frrscript_register_type_encoder(const char *typename,
+				     int (*encoder)(lua_State *L, void *))
+{
+	struct encoder e = {
+		.typename = (char *) typename,
+		.encoder = NULL
+	};
+
+	if (hash_lookup(encoder_hash, &e)) {
+		zlog_backtrace(LOG_ERR);
+		assert(!"Type encoder double-registered.");
+	}
+
+	hash_get(encoder_hash, &e, encoder_alloc);
+}
+
+
+struct frrscript *frrscript_load(const char *name,
+				 int (*load_cb)(struct frrscript *))
+{
+	struct frrscript *fs = XCALLOC(MTYPE_TMP, sizeof(struct frrscript));
+
+	fs->name = XSTRDUP(MTYPE_TMP, name);
+	fs->L = luaL_newstate();
+
+	char fname[MAXPATHLEN];
+	snprintf(fname, sizeof(fname), FRRSCRIPT_PATH "/%s.lua", fs->name);
+
+	if (luaL_loadfile(fs->L, fname) != LUA_OK)
+		goto fail;
+
+	if (load_cb && (*load_cb)(fs) != 0)
+		goto fail;
+
+	return fs;
+fail:
+	frrscript_unload(fs);
+	return NULL;
+}
+
+void frrscript_unload(struct frrscript *fs)
+{
+	XFREE(MTYPE_TMP, fs->name);
+	XFREE(MTYPE_TMP, fs);
+}
+
+void frrscript_init()
+{
+	encoder_hash = hash_create(encoder_hash_key, encoder_hash_cmp, "Lua type encoders");
+}