[mirror_frr.git] / lib / frrscript.h

/* 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
 */
#ifndef __FRRSCRIPT_H__
#define __FRRSCRIPT_H__

#include <zebra.h>

#ifdef HAVE_SCRIPTING

#include <lua.h>
#include <nexthop.h>
#include <nexthop_group.h>
#include "frrlua.h"
#include "bgpd/bgp_script.h" // for peer and attr encoders/decoders

#ifdef __cplusplus
extern "C" {
#endif

/* Forward declarations */
extern struct zebra_dplane_ctx ctx;
extern void lua_pushzebra_dplane_ctx(lua_State *L,
				     const struct zebra_dplane_ctx *ctx);
extern void lua_decode_zebra_dplane_ctx(lua_State *L, int idx,
					struct zebra_dplane_ctx *ctx);

/*
 * Script name hash
 */
PREDECL_HASH(frrscript_names);

struct frrscript_names_entry {
	/* Name of a Lua hook call */
	char function_name[MAXPATHLEN];

	/* Lua script in which to look for it */
	char script_name[MAXPATHLEN];

	struct frrscript_names_item item;
};

extern struct frrscript_names_head frrscript_names_hash;

int frrscript_names_hash_cmp(const struct frrscript_names_entry *snhe1,
			     const struct frrscript_names_entry *snhe2);
uint32_t frrscript_names_hash_key(const struct frrscript_names_entry *snhe);

DECLARE_HASH(frrscript_names, struct frrscript_names_entry, item,
	     frrscript_names_hash_cmp, frrscript_names_hash_key);

int frrscript_names_add_function_name(const char *function_name);
void frrscript_names_destroy(void);
int frrscript_names_set_script_name(const char *function_name,
				    const char *script_name);
char *frrscript_names_get_script_name(const char *function_name);

typedef void (*encoder_func)(lua_State *, const void *);
typedef void *(*decoder_func)(lua_State *, int);

struct frrscript_codec {
	const char *typename;
	encoder_func encoder;
	decoder_func decoder;
};

struct lua_function_state {
	const char *name;
	lua_State *L;
};

struct frrscript {
	/* Script name */
	char *name;

	/* Hash of Lua function name to Lua function state */
	struct hash *lua_function_hash;
};


/*
 * Hash related functions for lua_function_hash
 */

void *lua_function_alloc(void *arg);

unsigned int lua_function_hash_key(const void *data);

bool lua_function_hash_cmp(const void *d1, const void *d2);

struct frrscript_env {
	/* Value type */
	const char *typename;

	/* Binding name */
	const char *name;

	/* Value */
	const void *val;
};

/*
 * Create new struct frrscript for a Lua script.
 * This will hold the states for the Lua functions in this script.
 *
 * scriptname
 *     Name of the Lua script file, without the .lua
 */
struct frrscript *frrscript_new(const char *scriptname);

/*
 * Load a function into frrscript, run callback if any
 */
int frrscript_load(struct frrscript *fs, const char *function_name,
		   int (*load_cb)(struct frrscript *));

/*
 * Delete Lua function states and frrscript
 */
void frrscript_delete(struct frrscript *fs);

/*
 * Register a Lua codec for a type.
 *
 * tname
 *    Name of type; e.g., "peer", "ospf_interface", etc. Chosen at will.
 *
 * codec(s)
 *    Function pointer to codec struct. Encoder function should push a Lua
 *    table representing the passed argument - which will have the C type
 *    associated with the chosen 'tname' to the provided stack. The decoder
 *    function should pop a value from the top of the stack and return a heap
 *    chunk containing that value. Allocations should be made with MTYPE_TMP.
 *
 *    If using the plural function variant, pass a NULL-terminated array.
 *
 */
void frrscript_register_type_codec(struct frrscript_codec *codec);
void frrscript_register_type_codecs(struct frrscript_codec *codecs);

/*
 * Initialize scripting subsystem. Call this before anything else.
 *
 * scriptdir
 *    Directory in which to look for scripts
 */
void frrscript_init(const char *scriptdir);

/*
 * This macro is mapped to every (name, value) in frrscript_call,
 * so this in turn maps them onto their encoders
 */
#define ENCODE_ARGS(name, value) ENCODE_ARGS_WITH_STATE(lfs->L, (value))

/*
 * This macro is also mapped to every (name, value) in frrscript_call, but
 * not every value can be mapped to its decoder - only those that appear
 * in the returned table will. To find out if they appear in the returned
 * table, first pop the value and check if its nil. Only call the decoder
 * if non-nil.
 *
 * At the end, the only thing left on the stack should be the
 * returned table.
 */
#define DECODE_ARGS(name, value)                                               \
	do {                                                                   \
		lua_getfield(lfs->L, 1, (name));                               \
		if (lua_isnil(lfs->L, 2)) {                                    \
			lua_pop(lfs->L, 1);                                    \
		} else {                                                       \
			DECODE_ARGS_WITH_STATE(lfs->L, (value));               \
		}                                                              \
		assert(lua_gettop(lfs->L) == 1);                               \
	} while (0)

/*
 * Maps the type of value to its encoder/decoder.
 * Add new mappings here.
 *
 * L
 *    Lua state
 * scriptdir
 *    Directory in which to look for scripts
 */
#define ENCODE_ARGS_WITH_STATE(L, value)                                       \
	_Generic((value), \
int : lua_pushinteger,                                          \
long long * : lua_pushintegerp,                                 \
struct prefix * : lua_pushprefix,                               \
struct interface * : lua_pushinterface,                         \
struct in_addr * : lua_pushinaddr,                              \
struct in6_addr * : lua_pushin6addr,                            \
union sockunion * : lua_pushsockunion,                          \
time_t * : lua_pushtimet,                                       \
char * : lua_pushstring_wrapper,                                \
struct attr * : lua_pushattr,                                   \
struct peer * : lua_pushpeer,                                   \
const struct prefix * : lua_pushprefix,                         \
const struct ipaddr * : lua_pushipaddr,                         \
const struct ethaddr * : lua_pushethaddr,                       \
const struct nexthop_group * : lua_pushnexthop_group,           \
const struct nexthop * : lua_pushnexthop,                       \
struct zebra_dplane_ctx * : lua_pushzebra_dplane_ctx            \
)((L), (value))

#define DECODE_ARGS_WITH_STATE(L, value)                                       \
	_Generic((value), \
int : lua_decode_integer_noop,                                  \
long long * : lua_decode_integerp,                              \
struct prefix * : lua_decode_prefix,                            \
struct interface * : lua_decode_interface,                      \
struct in_addr * : lua_decode_inaddr,                           \
struct in6_addr * : lua_decode_in6addr,                         \
union sockunion * : lua_decode_sockunion,                       \
time_t * : lua_decode_timet,                                    \
char * : lua_decode_stringp,                                    \
struct attr * : lua_decode_attr,                                \
struct peer * : lua_decode_noop,                                \
const struct prefix * : lua_decode_noop,                        \
const struct ipaddr * : lua_decode_noop,                        \
const struct ethaddr * : lua_decode_noop,                       \
const struct nexthop_group * : lua_decode_noop,                 \
const struct nexthop * : lua_decode_noop,                       \
struct zebra_dplane_ctx * : lua_decode_noop                     \
)((L), -1, (value))

/*
 * Call Lua function state (abstraction for a single Lua function)
 *
 * lfs
 *    The Lua function to call; this should have been loaded in by
 *    frrscript_load(). nargs Number of arguments the function accepts
 *
 * Returns:
 *    0 if the script ran successfully, nonzero otherwise.
 */
int _frrscript_call_lua(struct lua_function_state *lfs, int nargs);

/*
 * Wrapper for calling Lua function state.
 *
 * The Lua function name (f) to run should have already been checked by
 * frrscript_load. So this wrapper will:
 * 1) Find the Lua function state, which contains the Lua state
 * 2) Clear the Lua state (there may be leftovers items from previous call)
 * 3) Push the Lua function (f)
 * 4) Map frrscript_call arguments onto their encoder and decoders, push those
 * 5) Call _frrscript_call_lua (Lua execution takes place)
 * 6) Write back to frrscript_call arguments using their decoders
 *
 * This wrapper can be called multiple times (after one frrscript_load).
 *
 * fs
 *    The struct frrscript in which the Lua fuction was loaded into
 * f
 *    Name of the Lua function.
 *
 * Returns:
 *    0 if the script ran successfully, nonzero otherwise.
 */
#define frrscript_call(fs, f, ...)                                                                                                                                 \
	({                                                                                                                                                         \
		struct lua_function_state lookup = {.name = (f)};                                                                                                  \
		struct lua_function_state *lfs;                                                                                                                    \
		lfs = hash_lookup((fs)->lua_function_hash, &lookup);                                                                                               \
		lfs == NULL ? ({                                                                                                                                   \
			zlog_err(                                                                                                                                  \
				"frrscript: '%s.lua': '%s': tried to call this function but it was not loaded",                                                    \
				(fs)->name, (f));                                                                                                                  \
			1;                                                                                                                                         \
		})                                                                                                                                                 \
			    : ({                                                                                                                                   \
				      lua_settop(lfs->L, 0);                                                                                                       \
				      lua_getglobal(lfs->L, f);                                                                                                    \
				      MAP_LISTS(ENCODE_ARGS, ##__VA_ARGS__);                                                                                       \
				      _frrscript_call_lua(                                                                                                         \
					      lfs, PP_NARG(__VA_ARGS__));                                                                                          \
			      }) != 0                                                                                                                              \
				      ? ({                                                                                                                         \
						zlog_err(                                                                                                          \
							"frrscript: '%s.lua': '%s': this function called but returned non-zero exit code. No variables modified.", \
							(fs)->name, (f));                                                                                          \
						1;                                                                                                                 \
					})                                                                                                                         \
				      : ({                                                                                                                         \
						MAP_LISTS(DECODE_ARGS,                                                                                             \
							  ##__VA_ARGS__);                                                                                          \
						0;                                                                                                                 \
					});                                                                                                                        \
	})

/*
 * Get result from finished function
 *
 * fs
 *    The script. This script must have been run already.
 * function_name
 *    Name of the Lua function.
 * name
 *    Name of the result.
 *    This will be used as a string key to retrieve from the table that the
 *    Lua function returns.
 *    The name here should *not* appear in frrscript_call.
 * lua_to
 *    Function pointer to a lua_to decoder function.
 *    This function should allocate and decode a value from the Lua state.
 *
 * Returns:
 *    A pointer to the decoded value from the Lua state, or NULL if no such
 *    value.
 */
void *frrscript_get_result(struct frrscript *fs, const char *function_name,
			   const char *name,
			   void *(*lua_to)(lua_State *L, int idx));

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* HAVE_SCRIPTING */

#endif /* __FRRSCRIPT_H__ */
Commit	Line	Data
5f98c815 QY	1	/* Scripting foo
	2	* Copyright (C) 2020 NVIDIA Corporation
	3	* Quentin Young
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; either version 2 of the License, or (at your option)
	8	* any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	* You should have received a copy of the GNU General Public License along
	16	* with this program; see the file COPYING; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	18	*/
	19	#ifndef __FRRSCRIPT_H__
	20	#define __FRRSCRIPT_H__
	21
fa22080d QY	22	#include <zebra.h>
	23
	24	#ifdef HAVE_SCRIPTING
	25
9e47ee98	26	#include <lua.h>
263951c1 DL	27	#include <nexthop.h>
263951c1 DL	28	#include <nexthop_group.h>
5f98c815	29	#include "frrlua.h"
6ffeb9f7	30	#include "bgpd/bgp_script.h" // for peer and attr encoders/decoders
5f98c815 QY	31
	32	#ifdef __cplusplus
	33	extern "C" {
	34	#endif
	35
263951c1 DL	36	/* Forward declarations */
	37	extern struct zebra_dplane_ctx ctx;
	38	extern void lua_pushzebra_dplane_ctx(lua_State *L,
	39	const struct zebra_dplane_ctx *ctx);
	40	extern void lua_decode_zebra_dplane_ctx(lua_State *L, int idx,
	41	struct zebra_dplane_ctx *ctx);
	42
a3ef7ae8 DL	43	/*
	44	* Script name hash
	45	*/
	46	PREDECL_HASH(frrscript_names);
	47
	48	struct frrscript_names_entry {
	49	/* Name of a Lua hook call */
	50	char function_name[MAXPATHLEN];
	51
	52	/* Lua script in which to look for it */
	53	char script_name[MAXPATHLEN];
	54
	55	struct frrscript_names_item item;
	56	};
	57
	58	extern struct frrscript_names_head frrscript_names_hash;
	59
	60	int frrscript_names_hash_cmp(const struct frrscript_names_entry *snhe1,
	61	const struct frrscript_names_entry *snhe2);
	62	uint32_t frrscript_names_hash_key(const struct frrscript_names_entry *snhe);
	63
	64	DECLARE_HASH(frrscript_names, struct frrscript_names_entry, item,
	65	frrscript_names_hash_cmp, frrscript_names_hash_key);
	66
	67	int frrscript_names_add_function_name(const char *function_name);
	68	void frrscript_names_destroy(void);
	69	int frrscript_names_set_script_name(const char *function_name,
	70	const char *script_name);
	71	char frrscript_names_get_script_name(const char function_name);
	72
47dd8736	73	typedef void (encoder_func)(lua_State , const void *);
f869ab17 QY	74	typedef void (decoder_func)(lua_State *, int);
	75
	76	struct frrscript_codec {
	77	const char *typename;
	78	encoder_func encoder;
	79	decoder_func decoder;
	80	};
f944ec67	81
105ba9af DL	82	struct lua_function_state {
	83	const char *name;
	84	lua_State *L;
	85	};
	86
5f98c815 QY	87	struct frrscript {
	88	/* Script name */
	89	char *name;
	90
105ba9af DL	91	/* Hash of Lua function name to Lua function state */
105ba9af DL	92	struct hash *lua_function_hash;
5f98c815 QY	93	};
5f98c815 QY	94
105ba9af DL	95
	96	/*
	97	* Hash related functions for lua_function_hash
	98	*/
	99
	100	void lua_function_alloc(void arg);
	101
	102	unsigned int lua_function_hash_key(const void *data);
	103
	104	bool lua_function_hash_cmp(const void d1, const void d2);
	105
f869ab17 QY	106	struct frrscript_env {
	107	/* Value type */
	108	const char *typename;
	109
	110	/* Binding name */
	111	const char *name;
	112
	113	/* Value */
	114	const void *val;
	115	};
5f98c815 QY	116
5f98c815 QY	117	/*
7472871e DL	118	* Create new struct frrscript for a Lua script.
	119	* This will hold the states for the Lua functions in this script.
	120	*
	121	* scriptname
	122	* Name of the Lua script file, without the .lua
5f98c815	123	*/
7472871e	124	struct frrscript frrscript_new(const char scriptname);
f0cddf95 DL	125
	126	/*
	127	* Load a function into frrscript, run callback if any
	128	*/
	129	int frrscript_load(struct frrscript fs, const char function_name,
	130	int (load_cb)(struct frrscript ));
5f98c815 QY	131
5f98c815 QY	132	/*
7472871e	133	* Delete Lua function states and frrscript
5f98c815	134	*/
64d457d7	135	void frrscript_delete(struct frrscript *fs);
5f98c815 QY	136
5f98c815 QY	137	/*
f869ab17	138	* Register a Lua codec for a type.
5f98c815 QY	139	*
	140	* tname
	141	* Name of type; e.g., "peer", "ospf_interface", etc. Chosen at will.
	142	*
f869ab17 QY	143	* codec(s)
f869ab17 QY	144	* Function pointer to codec struct. Encoder function should push a Lua
5f98c815	145	* table representing the passed argument - which will have the C type
f869ab17 QY	146	* associated with the chosen 'tname' to the provided stack. The decoder
	147	* function should pop a value from the top of the stack and return a heap
	148	* chunk containing that value. Allocations should be made with MTYPE_TMP.
	149	*
	150	* If using the plural function variant, pass a NULL-terminated array.
5f98c815 QY	151	*
5f98c815 QY	152	*/
f869ab17 QY	153	void frrscript_register_type_codec(struct frrscript_codec *codec);
f869ab17 QY	154	void frrscript_register_type_codecs(struct frrscript_codec *codecs);
5f98c815 QY	155
	156	/*
	157	* Initialize scripting subsystem. Call this before anything else.
e4e0229a QY	158	*
	159	* scriptdir
	160	* Directory in which to look for scripts
5f98c815	161	*/
e4e0229a	162	void frrscript_init(const char *scriptdir);
5f98c815	163
70d995ab DL	164	/*
	165	* This macro is mapped to every (name, value) in frrscript_call,
	166	* so this in turn maps them onto their encoders
	167	*/
b5e790ee	168	#define ENCODE_ARGS(name, value) ENCODE_ARGS_WITH_STATE(lfs->L, (value))
43a5106d	169
70d995ab DL	170	/*
	171	* This macro is also mapped to every (name, value) in frrscript_call, but
	172	* not every value can be mapped to its decoder - only those that appear
	173	* in the returned table will. To find out if they appear in the returned
	174	* table, first pop the value and check if its nil. Only call the decoder
	175	* if non-nil.
	176	*
	177	* At the end, the only thing left on the stack should be the
	178	* returned table.
	179	*/
43a5106d DL	180	#define DECODE_ARGS(name, value) \
43a5106d DL	181	do { \
b5e790ee	182	lua_getfield(lfs->L, 1, (name)); \
24ff8520 DL	183	if (lua_isnil(lfs->L, 2)) { \
	184	lua_pop(lfs->L, 1); \
	185	} else { \
b5e790ee	186	DECODE_ARGS_WITH_STATE(lfs->L, (value)); \
24ff8520 DL	187	} \
24ff8520 DL	188	assert(lua_gettop(lfs->L) == 1); \
43a5106d DL	189	} while (0)
43a5106d DL	190
19eee398 DL	191	/*
	192	* Maps the type of value to its encoder/decoder.
	193	* Add new mappings here.
	194	*
	195	* L
	196	* Lua state
	197	* scriptdir
	198	* Directory in which to look for scripts
	199	*/
c2642aab DL	200	#define ENCODE_ARGS_WITH_STATE(L, value) \
c2642aab DL	201	_Generic((value), \
2ce634e2	202	int : lua_pushinteger, \
c2642aab DL	203	long long * : lua_pushintegerp, \
	204	struct prefix * : lua_pushprefix, \
	205	struct interface * : lua_pushinterface, \
	206	struct in_addr * : lua_pushinaddr, \
	207	struct in6_addr * : lua_pushin6addr, \
	208	union sockunion * : lua_pushsockunion, \
	209	time_t * : lua_pushtimet, \
b7da61c1 DL	210	char * : lua_pushstring_wrapper, \
b7da61c1 DL	211	struct attr * : lua_pushattr, \
81fde499	212	struct peer * : lua_pushpeer, \
263951c1 DL	213	const struct prefix * : lua_pushprefix, \
	214	const struct ipaddr * : lua_pushipaddr, \
	215	const struct ethaddr * : lua_pushethaddr, \
	216	const struct nexthop_group * : lua_pushnexthop_group, \
	217	const struct nexthop * : lua_pushnexthop, \
	218	struct zebra_dplane_ctx * : lua_pushzebra_dplane_ctx \
b5e790ee	219	)((L), (value))
43a5106d	220
3a3cfe47 DL	221	#define DECODE_ARGS_WITH_STATE(L, value) \
3a3cfe47 DL	222	_Generic((value), \
36cf58c7	223	int : lua_decode_integer_noop, \
3a3cfe47 DL	224	long long * : lua_decode_integerp, \
	225	struct prefix * : lua_decode_prefix, \
	226	struct interface * : lua_decode_interface, \
	227	struct in_addr * : lua_decode_inaddr, \
	228	struct in6_addr * : lua_decode_in6addr, \
	229	union sockunion * : lua_decode_sockunion, \
	230	time_t * : lua_decode_timet, \
b7da61c1	231	char * : lua_decode_stringp, \
81fde499 DL	232	struct attr * : lua_decode_attr, \
81fde499 DL	233	struct peer * : lua_decode_noop, \
263951c1 DL	234	const struct prefix * : lua_decode_noop, \
	235	const struct ipaddr * : lua_decode_noop, \
	236	const struct ethaddr * : lua_decode_noop, \
	237	const struct nexthop_group * : lua_decode_noop, \
	238	const struct nexthop * : lua_decode_noop, \
	239	struct zebra_dplane_ctx * : lua_decode_noop \
b5e790ee	240	)((L), -1, (value))
5f98c815 QY	241
5f98c815 QY	242	/*
7472871e	243	* Call Lua function state (abstraction for a single Lua function)
3b002f19	244	*
7472871e	245	* lfs
2ce634e2	246	* The Lua function to call; this should have been loaded in by
08bf2b41	247	* frrscript_load(). nargs Number of arguments the function accepts
3b002f19	248	*
f869ab17 QY	249	* Returns:
f869ab17 QY	250	* 0 if the script ran successfully, nonzero otherwise.
3b002f19	251	*/
40d038d2	252	int _frrscript_call_lua(struct lua_function_state *lfs, int nargs);
43a5106d	253
19eee398	254	/*
2ed598ba DL	255	* Wrapper for calling Lua function state.
	256	*
	257	* The Lua function name (f) to run should have already been checked by
	258	* frrscript_load. So this wrapper will:
	259	* 1) Find the Lua function state, which contains the Lua state
	260	* 2) Clear the Lua state (there may be leftovers items from previous call)
	261	* 3) Push the Lua function (f)
	262	* 4) Map frrscript_call arguments onto their encoder and decoders, push those
	263	* 5) Call _frrscript_call_lua (Lua execution takes place)
	264	* 6) Write back to frrscript_call arguments using their decoders
	265	*
	266	* This wrapper can be called multiple times (after one frrscript_load).
19eee398 DL	267	*
19eee398 DL	268	* fs
7472871e DL	269	* The struct frrscript in which the Lua fuction was loaded into
	270	* f
	271	* Name of the Lua function.
19eee398 DL	272	*
	273	* Returns:
	274	* 0 if the script ran successfully, nonzero otherwise.
	275	*/
2ce634e2 DL	276	#define frrscript_call(fs, f, ...) \
2ce634e2 DL	277	({ \
67b64027	278	struct lua_function_state lookup = {.name = (f)}; \
2ce634e2	279	struct lua_function_state *lfs; \
67b64027	280	lfs = hash_lookup((fs)->lua_function_hash, &lookup); \
2ce634e2 DL	281	lfs == NULL ? ({ \
	282	zlog_err( \
	283	"frrscript: '%s.lua': '%s': tried to call this function but it was not loaded", \
67b64027	284	(fs)->name, (f)); \
2ce634e2 DL	285	1; \
	286	}) \
	287	: ({ \
2ed598ba DL	288	lua_settop(lfs->L, 0); \
2ed598ba DL	289	lua_getglobal(lfs->L, f); \
2ce634e2 DL	290	MAP_LISTS(ENCODE_ARGS, ##__VA_ARGS__); \
	291	_frrscript_call_lua( \
	292	lfs, PP_NARG(__VA_ARGS__)); \
	293	}) != 0 \
	294	? ({ \
	295	zlog_err( \
	296	"frrscript: '%s.lua': '%s': this function called but returned non-zero exit code. No variables modified.", \
67b64027	297	(fs)->name, (f)); \
2ce634e2 DL	298	1; \
	299	}) \
	300	: ({ \
	301	MAP_LISTS(DECODE_ARGS, \
	302	##__VA_ARGS__); \
	303	0; \
	304	}); \
43a5106d	305	})
3b002f19 QY	306
3b002f19 QY	307	/*
7472871e	308	* Get result from finished function
3b002f19	309	*
f869ab17 QY	310	* fs
f869ab17 QY	311	* The script. This script must have been run already.
7472871e DL	312	* function_name
	313	* Name of the Lua function.
	314	* name
	315	* Name of the result.
	316	* This will be used as a string key to retrieve from the table that the
	317	* Lua function returns.
	318	* The name here should not appear in frrscript_call.
	319	* lua_to
	320	* Function pointer to a lua_to decoder function.
	321	* This function should allocate and decode a value from the Lua state.
3b002f19	322	*
f869ab17	323	* Returns:
7472871e DL	324	* A pointer to the decoded value from the Lua state, or NULL if no such
7472871e DL	325	* value.
3b002f19	326	*/
06947dde DL	327	void frrscript_get_result(struct frrscript fs, const char *function_name,
	328	const char *name,
	329	void (lua_to)(lua_State *L, int idx));
3b002f19	330
5f98c815 QY	331	#ifdef __cplusplus
	332	}
	333	#endif /* __cplusplus */
	334
fa22080d QY	335	#endif /* HAVE_SCRIPTING */
fa22080d QY	336
5f98c815	337	#endif /* __FRRSCRIPT_H__ */