xref: /vim-8.2.3635/src/if_lua.c (revision 01a6c216)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Lua interface by Luis Carvalho
6  *
7  * Do ":help uganda"  in Vim to read copying and usage conditions.
8  * Do ":help credits" in Vim to see a list of people who contributed.
9  * See README.txt for an overview of the Vim source code.
10  */
11 
12 #include "vim.h"
13 
14 #include <lua.h>
15 #include <lualib.h>
16 #include <lauxlib.h>
17 
18 /* Only do the following when the feature is enabled.  Needed for "make
19  * depend". */
20 #if defined(FEAT_LUA) || defined(PROTO)
21 
22 #define LUAVIM_CHUNKNAME "vim chunk"
23 #define LUAVIM_NAME "vim"
24 #define LUAVIM_EVALNAME "luaeval"
25 #define LUAVIM_EVALHEADER "local _A=select(1,...) return "
26 
27 typedef buf_T *luaV_Buffer;
28 typedef win_T *luaV_Window;
29 typedef dict_T *luaV_Dict;
30 typedef list_T *luaV_List;
31 typedef struct {
32     typval_T	tv;	// funcref
33     typval_T	args;
34     dict_T	*self;	// selfdict
35 } luaV_Funcref;
36 typedef void (*msgfunc_T)(char_u *);
37 
38 static const char LUAVIM_DICT[] = "dict";
39 static const char LUAVIM_LIST[] = "list";
40 static const char LUAVIM_FUNCREF[] = "funcref";
41 static const char LUAVIM_BUFFER[] = "buffer";
42 static const char LUAVIM_WINDOW[] = "window";
43 static const char LUAVIM_FREE[] = "luaV_free";
44 static const char LUAVIM_LUAEVAL[] = "luaV_luaeval";
45 static const char LUAVIM_SETREF[] = "luaV_setref";
46 
47 /* most functions are closures with a cache table as first upvalue;
48  * get/setudata manage references to vim userdata in cache table through
49  * object pointers (light userdata) */
50 #define luaV_getudata(L, v) \
51     lua_pushlightuserdata((L), (void *) (v)); \
52     lua_rawget((L), lua_upvalueindex(1))
53 #define luaV_setudata(L, v) \
54     lua_pushlightuserdata((L), (void *) (v)); \
55     lua_pushvalue((L), -2); \
56     lua_rawset((L), lua_upvalueindex(1))
57 #define luaV_getfield(L, s) \
58     lua_pushlightuserdata((L), (void *)(s)); \
59     lua_rawget((L), LUA_REGISTRYINDEX)
60 #define luaV_checksandbox(L) \
61     if (sandbox) luaL_error((L), "not allowed in sandbox")
62 #define luaV_msg(L) luaV_msgfunc((L), (msgfunc_T) msg)
63 #define luaV_emsg(L) luaV_msgfunc((L), (msgfunc_T) emsg)
64 #define luaV_checktypval(L, a, v, msg) \
65     do { \
66         if (luaV_totypval(L, a, v) == FAIL) \
67 	    luaL_error(L, msg ": cannot convert value"); \
68     } while (0)
69 
70 static luaV_List *luaV_pushlist(lua_State *L, list_T *lis);
71 static luaV_Dict *luaV_pushdict(lua_State *L, dict_T *dic);
72 static luaV_Funcref *luaV_pushfuncref(lua_State *L, typval_T *tv);
73 
74 #if LUA_VERSION_NUM <= 501
75 #define luaV_openlib(L, l, n) luaL_openlib(L, NULL, l, n)
76 #define luaL_typeerror luaL_typerror
77 #else
78 #define luaV_openlib luaL_setfuncs
79 #endif
80 
81 #ifdef DYNAMIC_LUA
82 
83 #ifndef WIN3264
84 # include <dlfcn.h>
85 # define HANDLE void*
86 # define load_dll(n) dlopen((n), RTLD_LAZY|RTLD_GLOBAL)
87 # define symbol_from_dll dlsym
88 # define close_dll dlclose
89 #else
90 # define load_dll vimLoadLib
91 # define symbol_from_dll GetProcAddress
92 # define close_dll FreeLibrary
93 #endif
94 
95 /* lauxlib */
96 #if LUA_VERSION_NUM <= 501
97 #define luaL_register dll_luaL_register
98 #define luaL_prepbuffer dll_luaL_prepbuffer
99 #define luaL_openlib dll_luaL_openlib
100 #define luaL_typerror dll_luaL_typerror
101 #define luaL_loadfile dll_luaL_loadfile
102 #define luaL_loadbuffer dll_luaL_loadbuffer
103 #else
104 #define luaL_prepbuffsize dll_luaL_prepbuffsize
105 #define luaL_setfuncs dll_luaL_setfuncs
106 #define luaL_loadfilex dll_luaL_loadfilex
107 #define luaL_loadbufferx dll_luaL_loadbufferx
108 #define luaL_argerror dll_luaL_argerror
109 #endif
110 #define luaL_checkany dll_luaL_checkany
111 #define luaL_checklstring dll_luaL_checklstring
112 #define luaL_checkinteger dll_luaL_checkinteger
113 #define luaL_optinteger dll_luaL_optinteger
114 #define luaL_checktype dll_luaL_checktype
115 #define luaL_error dll_luaL_error
116 #define luaL_newstate dll_luaL_newstate
117 #define luaL_buffinit dll_luaL_buffinit
118 #define luaL_addlstring dll_luaL_addlstring
119 #define luaL_pushresult dll_luaL_pushresult
120 /* lua */
121 #if LUA_VERSION_NUM <= 501
122 #define lua_tonumber dll_lua_tonumber
123 #define lua_tointeger dll_lua_tointeger
124 #define lua_call dll_lua_call
125 #define lua_pcall dll_lua_pcall
126 #else
127 #define lua_tonumberx dll_lua_tonumberx
128 #define lua_tointegerx dll_lua_tointegerx
129 #define lua_callk dll_lua_callk
130 #define lua_pcallk dll_lua_pcallk
131 #define lua_getglobal dll_lua_getglobal
132 #define lua_setglobal dll_lua_setglobal
133 #endif
134 #if LUA_VERSION_NUM <= 502
135 #define lua_replace dll_lua_replace
136 #define lua_remove dll_lua_remove
137 #endif
138 #if LUA_VERSION_NUM >= 503
139 #define lua_rotate dll_lua_rotate
140 #define lua_copy dll_lua_copy
141 #endif
142 #define lua_typename dll_lua_typename
143 #define lua_close dll_lua_close
144 #define lua_gettop dll_lua_gettop
145 #define lua_settop dll_lua_settop
146 #define lua_pushvalue dll_lua_pushvalue
147 #define lua_isnumber dll_lua_isnumber
148 #define lua_isstring dll_lua_isstring
149 #define lua_type dll_lua_type
150 #define lua_rawequal dll_lua_rawequal
151 #define lua_toboolean dll_lua_toboolean
152 #define lua_tolstring dll_lua_tolstring
153 #define lua_touserdata dll_lua_touserdata
154 #define lua_pushnil dll_lua_pushnil
155 #define lua_pushnumber dll_lua_pushnumber
156 #define lua_pushinteger dll_lua_pushinteger
157 #define lua_pushlstring dll_lua_pushlstring
158 #define lua_pushstring dll_lua_pushstring
159 #define lua_pushfstring dll_lua_pushfstring
160 #define lua_pushcclosure dll_lua_pushcclosure
161 #define lua_pushboolean dll_lua_pushboolean
162 #define lua_pushlightuserdata dll_lua_pushlightuserdata
163 #define lua_getfield dll_lua_getfield
164 #define lua_rawget dll_lua_rawget
165 #define lua_rawgeti dll_lua_rawgeti
166 #define lua_createtable dll_lua_createtable
167 #if LUA_VERSION_NUM >= 504
168  #define lua_newuserdatauv dll_lua_newuserdatauv
169 #else
170  #define lua_newuserdata dll_lua_newuserdata
171 #endif
172 #define lua_getmetatable dll_lua_getmetatable
173 #define lua_setfield dll_lua_setfield
174 #define lua_rawset dll_lua_rawset
175 #define lua_rawseti dll_lua_rawseti
176 #define lua_setmetatable dll_lua_setmetatable
177 #define lua_next dll_lua_next
178 /* libs */
179 #define luaopen_base dll_luaopen_base
180 #define luaopen_table dll_luaopen_table
181 #define luaopen_string dll_luaopen_string
182 #define luaopen_math dll_luaopen_math
183 #define luaopen_io dll_luaopen_io
184 #define luaopen_os dll_luaopen_os
185 #define luaopen_package dll_luaopen_package
186 #define luaopen_debug dll_luaopen_debug
187 #define luaL_openlibs dll_luaL_openlibs
188 
189 /* lauxlib */
190 #if LUA_VERSION_NUM <= 501
191 void (*dll_luaL_register) (lua_State *L, const char *libname, const luaL_Reg *l);
192 char *(*dll_luaL_prepbuffer) (luaL_Buffer *B);
193 void (*dll_luaL_openlib) (lua_State *L, const char *libname, const luaL_Reg *l, int nup);
194 int (*dll_luaL_typerror) (lua_State *L, int narg, const char *tname);
195 int (*dll_luaL_loadfile) (lua_State *L, const char *filename);
196 int (*dll_luaL_loadbuffer) (lua_State *L, const char *buff, size_t sz, const char *name);
197 #else
198 char *(*dll_luaL_prepbuffsize) (luaL_Buffer *B, size_t sz);
199 void (*dll_luaL_setfuncs) (lua_State *L, const luaL_Reg *l, int nup);
200 int (*dll_luaL_loadfilex) (lua_State *L, const char *filename, const char *mode);
201 int (*dll_luaL_loadbufferx) (lua_State *L, const char *buff, size_t sz, const char *name, const char *mode);
202 int (*dll_luaL_argerror) (lua_State *L, int numarg, const char *extramsg);
203 #endif
204 void (*dll_luaL_checkany) (lua_State *L, int narg);
205 const char *(*dll_luaL_checklstring) (lua_State *L, int numArg, size_t *l);
206 lua_Integer (*dll_luaL_checkinteger) (lua_State *L, int numArg);
207 lua_Integer (*dll_luaL_optinteger) (lua_State *L, int nArg, lua_Integer def);
208 void (*dll_luaL_checktype) (lua_State *L, int narg, int t);
209 int (*dll_luaL_error) (lua_State *L, const char *fmt, ...);
210 lua_State *(*dll_luaL_newstate) (void);
211 void (*dll_luaL_buffinit) (lua_State *L, luaL_Buffer *B);
212 void (*dll_luaL_addlstring) (luaL_Buffer *B, const char *s, size_t l);
213 void (*dll_luaL_pushresult) (luaL_Buffer *B);
214 /* lua */
215 #if LUA_VERSION_NUM <= 501
216 lua_Number (*dll_lua_tonumber) (lua_State *L, int idx);
217 lua_Integer (*dll_lua_tointeger) (lua_State *L, int idx);
218 void (*dll_lua_call) (lua_State *L, int nargs, int nresults);
219 int (*dll_lua_pcall) (lua_State *L, int nargs, int nresults, int errfunc);
220 #else
221 lua_Number (*dll_lua_tonumberx) (lua_State *L, int idx, int *isnum);
222 lua_Integer (*dll_lua_tointegerx) (lua_State *L, int idx, int *isnum);
223 void (*dll_lua_callk) (lua_State *L, int nargs, int nresults, int ctx,
224 	lua_CFunction k);
225 int (*dll_lua_pcallk) (lua_State *L, int nargs, int nresults, int errfunc,
226 	int ctx, lua_CFunction k);
227 void (*dll_lua_getglobal) (lua_State *L, const char *var);
228 void (*dll_lua_setglobal) (lua_State *L, const char *var);
229 #endif
230 #if LUA_VERSION_NUM <= 502
231 void (*dll_lua_replace) (lua_State *L, int idx);
232 void (*dll_lua_remove) (lua_State *L, int idx);
233 #endif
234 #if LUA_VERSION_NUM >= 503
235 void  (*dll_lua_rotate) (lua_State *L, int idx, int n);
236 void (*dll_lua_copy) (lua_State *L, int fromidx, int toidx);
237 #endif
238 const char *(*dll_lua_typename) (lua_State *L, int tp);
239 void       (*dll_lua_close) (lua_State *L);
240 int (*dll_lua_gettop) (lua_State *L);
241 void (*dll_lua_settop) (lua_State *L, int idx);
242 void (*dll_lua_pushvalue) (lua_State *L, int idx);
243 int (*dll_lua_isnumber) (lua_State *L, int idx);
244 int (*dll_lua_isstring) (lua_State *L, int idx);
245 int (*dll_lua_type) (lua_State *L, int idx);
246 int (*dll_lua_rawequal) (lua_State *L, int idx1, int idx2);
247 int (*dll_lua_toboolean) (lua_State *L, int idx);
248 const char *(*dll_lua_tolstring) (lua_State *L, int idx, size_t *len);
249 void *(*dll_lua_touserdata) (lua_State *L, int idx);
250 void (*dll_lua_pushnil) (lua_State *L);
251 void (*dll_lua_pushnumber) (lua_State *L, lua_Number n);
252 void (*dll_lua_pushinteger) (lua_State *L, lua_Integer n);
253 void (*dll_lua_pushlstring) (lua_State *L, const char *s, size_t l);
254 void (*dll_lua_pushstring) (lua_State *L, const char *s);
255 const char *(*dll_lua_pushfstring) (lua_State *L, const char *fmt, ...);
256 void (*dll_lua_pushcclosure) (lua_State *L, lua_CFunction fn, int n);
257 void (*dll_lua_pushboolean) (lua_State *L, int b);
258 void (*dll_lua_pushlightuserdata) (lua_State *L, void *p);
259 void (*dll_lua_getfield) (lua_State *L, int idx, const char *k);
260 #if LUA_VERSION_NUM <= 502
261 void (*dll_lua_rawget) (lua_State *L, int idx);
262 void (*dll_lua_rawgeti) (lua_State *L, int idx, int n);
263 #else
264 int (*dll_lua_rawget) (lua_State *L, int idx);
265 int (*dll_lua_rawgeti) (lua_State *L, int idx, lua_Integer n);
266 #endif
267 void (*dll_lua_createtable) (lua_State *L, int narr, int nrec);
268 #if LUA_VERSION_NUM >= 504
269 void *(*dll_lua_newuserdatauv) (lua_State *L, size_t sz, int nuvalue);
270 #else
271 void *(*dll_lua_newuserdata) (lua_State *L, size_t sz);
272 #endif
273 int (*dll_lua_getmetatable) (lua_State *L, int objindex);
274 void (*dll_lua_setfield) (lua_State *L, int idx, const char *k);
275 void (*dll_lua_rawset) (lua_State *L, int idx);
276 #if LUA_VERSION_NUM <= 502
277 void (*dll_lua_rawseti) (lua_State *L, int idx, int n);
278 #else
279 void (*dll_lua_rawseti) (lua_State *L, int idx, lua_Integer n);
280 #endif
281 int (*dll_lua_setmetatable) (lua_State *L, int objindex);
282 int (*dll_lua_next) (lua_State *L, int idx);
283 /* libs */
284 int (*dll_luaopen_base) (lua_State *L);
285 int (*dll_luaopen_table) (lua_State *L);
286 int (*dll_luaopen_string) (lua_State *L);
287 int (*dll_luaopen_math) (lua_State *L);
288 int (*dll_luaopen_io) (lua_State *L);
289 int (*dll_luaopen_os) (lua_State *L);
290 int (*dll_luaopen_package) (lua_State *L);
291 int (*dll_luaopen_debug) (lua_State *L);
292 void (*dll_luaL_openlibs) (lua_State *L);
293 
294 typedef void **luaV_function;
295 typedef struct {
296     const char *name;
297     luaV_function func;
298 } luaV_Reg;
299 
300 static const luaV_Reg luaV_dll[] = {
301     /* lauxlib */
302 #if LUA_VERSION_NUM <= 501
303     {"luaL_register", (luaV_function) &dll_luaL_register},
304     {"luaL_prepbuffer", (luaV_function) &dll_luaL_prepbuffer},
305     {"luaL_openlib", (luaV_function) &dll_luaL_openlib},
306     {"luaL_typerror", (luaV_function) &dll_luaL_typerror},
307     {"luaL_loadfile", (luaV_function) &dll_luaL_loadfile},
308     {"luaL_loadbuffer", (luaV_function) &dll_luaL_loadbuffer},
309 #else
310     {"luaL_prepbuffsize", (luaV_function) &dll_luaL_prepbuffsize},
311     {"luaL_setfuncs", (luaV_function) &dll_luaL_setfuncs},
312     {"luaL_loadfilex", (luaV_function) &dll_luaL_loadfilex},
313     {"luaL_loadbufferx", (luaV_function) &dll_luaL_loadbufferx},
314     {"luaL_argerror", (luaV_function) &dll_luaL_argerror},
315 #endif
316     {"luaL_checkany", (luaV_function) &dll_luaL_checkany},
317     {"luaL_checklstring", (luaV_function) &dll_luaL_checklstring},
318     {"luaL_checkinteger", (luaV_function) &dll_luaL_checkinteger},
319     {"luaL_optinteger", (luaV_function) &dll_luaL_optinteger},
320     {"luaL_checktype", (luaV_function) &dll_luaL_checktype},
321     {"luaL_error", (luaV_function) &dll_luaL_error},
322     {"luaL_newstate", (luaV_function) &dll_luaL_newstate},
323     {"luaL_buffinit", (luaV_function) &dll_luaL_buffinit},
324     {"luaL_addlstring", (luaV_function) &dll_luaL_addlstring},
325     {"luaL_pushresult", (luaV_function) &dll_luaL_pushresult},
326     /* lua */
327 #if LUA_VERSION_NUM <= 501
328     {"lua_tonumber", (luaV_function) &dll_lua_tonumber},
329     {"lua_tointeger", (luaV_function) &dll_lua_tointeger},
330     {"lua_call", (luaV_function) &dll_lua_call},
331     {"lua_pcall", (luaV_function) &dll_lua_pcall},
332 #else
333     {"lua_tonumberx", (luaV_function) &dll_lua_tonumberx},
334     {"lua_tointegerx", (luaV_function) &dll_lua_tointegerx},
335     {"lua_callk", (luaV_function) &dll_lua_callk},
336     {"lua_pcallk", (luaV_function) &dll_lua_pcallk},
337     {"lua_getglobal", (luaV_function) &dll_lua_getglobal},
338     {"lua_setglobal", (luaV_function) &dll_lua_setglobal},
339 #endif
340 #if LUA_VERSION_NUM <= 502
341     {"lua_replace", (luaV_function) &dll_lua_replace},
342     {"lua_remove", (luaV_function) &dll_lua_remove},
343 #endif
344 #if LUA_VERSION_NUM >= 503
345     {"lua_rotate", (luaV_function) &dll_lua_rotate},
346     {"lua_copy", (luaV_function) &dll_lua_copy},
347 #endif
348     {"lua_typename", (luaV_function) &dll_lua_typename},
349     {"lua_close", (luaV_function) &dll_lua_close},
350     {"lua_gettop", (luaV_function) &dll_lua_gettop},
351     {"lua_settop", (luaV_function) &dll_lua_settop},
352     {"lua_pushvalue", (luaV_function) &dll_lua_pushvalue},
353     {"lua_isnumber", (luaV_function) &dll_lua_isnumber},
354     {"lua_isstring", (luaV_function) &dll_lua_isstring},
355     {"lua_type", (luaV_function) &dll_lua_type},
356     {"lua_rawequal", (luaV_function) &dll_lua_rawequal},
357     {"lua_toboolean", (luaV_function) &dll_lua_toboolean},
358     {"lua_tolstring", (luaV_function) &dll_lua_tolstring},
359     {"lua_touserdata", (luaV_function) &dll_lua_touserdata},
360     {"lua_pushnil", (luaV_function) &dll_lua_pushnil},
361     {"lua_pushnumber", (luaV_function) &dll_lua_pushnumber},
362     {"lua_pushinteger", (luaV_function) &dll_lua_pushinteger},
363     {"lua_pushlstring", (luaV_function) &dll_lua_pushlstring},
364     {"lua_pushstring", (luaV_function) &dll_lua_pushstring},
365     {"lua_pushfstring", (luaV_function) &dll_lua_pushfstring},
366     {"lua_pushcclosure", (luaV_function) &dll_lua_pushcclosure},
367     {"lua_pushboolean", (luaV_function) &dll_lua_pushboolean},
368     {"lua_pushlightuserdata", (luaV_function) &dll_lua_pushlightuserdata},
369     {"lua_getfield", (luaV_function) &dll_lua_getfield},
370     {"lua_rawget", (luaV_function) &dll_lua_rawget},
371     {"lua_rawgeti", (luaV_function) &dll_lua_rawgeti},
372     {"lua_createtable", (luaV_function) &dll_lua_createtable},
373 #if LUA_VERSION_NUM >= 504
374     {"lua_newuserdatauv", (luaV_function) &dll_lua_newuserdatauv},
375 #else
376     {"lua_newuserdata", (luaV_function) &dll_lua_newuserdata},
377 #endif
378     {"lua_getmetatable", (luaV_function) &dll_lua_getmetatable},
379     {"lua_setfield", (luaV_function) &dll_lua_setfield},
380     {"lua_rawset", (luaV_function) &dll_lua_rawset},
381     {"lua_rawseti", (luaV_function) &dll_lua_rawseti},
382     {"lua_setmetatable", (luaV_function) &dll_lua_setmetatable},
383     {"lua_next", (luaV_function) &dll_lua_next},
384     /* libs */
385     {"luaopen_base", (luaV_function) &dll_luaopen_base},
386     {"luaopen_table", (luaV_function) &dll_luaopen_table},
387     {"luaopen_string", (luaV_function) &dll_luaopen_string},
388     {"luaopen_math", (luaV_function) &dll_luaopen_math},
389     {"luaopen_io", (luaV_function) &dll_luaopen_io},
390     {"luaopen_os", (luaV_function) &dll_luaopen_os},
391     {"luaopen_package", (luaV_function) &dll_luaopen_package},
392     {"luaopen_debug", (luaV_function) &dll_luaopen_debug},
393     {"luaL_openlibs", (luaV_function) &dll_luaL_openlibs},
394     {NULL, NULL}
395 };
396 
397 static HANDLE hinstLua = NULL;
398 
399     static void
400 end_dynamic_lua(void)
401 {
402     if (hinstLua)
403     {
404 	close_dll(hinstLua);
405 	hinstLua = 0;
406     }
407 }
408 
409     static int
410 lua_link_init(char *libname, int verbose)
411 {
412     const luaV_Reg *reg;
413     if (hinstLua) return OK;
414     hinstLua = load_dll(libname);
415     if (!hinstLua)
416     {
417 	if (verbose)
418 	    semsg(_(e_loadlib), libname);
419 	return FAIL;
420     }
421     for (reg = luaV_dll; reg->func; reg++)
422     {
423 	if ((*reg->func = symbol_from_dll(hinstLua, reg->name)) == NULL)
424 	{
425 	    close_dll(hinstLua);
426 	    hinstLua = 0;
427 	    if (verbose)
428 		semsg(_(e_loadfunc), reg->name);
429 	    return FAIL;
430 	}
431     }
432     return OK;
433 }
434 #endif /* DYNAMIC_LUA */
435 
436 #if defined(DYNAMIC_LUA) || defined(PROTO)
437     int
438 lua_enabled(int verbose)
439 {
440     return lua_link_init((char *)p_luadll, verbose) == OK;
441 }
442 #endif
443 
444 #if LUA_VERSION_NUM > 501
445     static int
446 luaL_typeerror (lua_State *L, int narg, const char *tname)
447 {
448     const char *msg = lua_pushfstring(L, "%s expected, got %s",
449 	    tname, luaL_typename(L, narg));
450     return luaL_argerror(L, narg, msg);
451 }
452 #endif
453 
454 
455 /* =======   Internal   ======= */
456 
457     static void
458 luaV_newmetatable(lua_State *L, const char *tname)
459 {
460     lua_newtable(L);
461     lua_pushlightuserdata(L, (void *) tname);
462     lua_pushvalue(L, -2);
463     lua_rawset(L, LUA_REGISTRYINDEX);
464 }
465 
466     static void *
467 luaV_toudata(lua_State *L, int ud, const char *tname)
468 {
469     void *p = lua_touserdata(L, ud);
470 
471     if (p != NULL) /* value is userdata? */
472     {
473 	if (lua_getmetatable(L, ud)) /* does it have a metatable? */
474 	{
475 	    luaV_getfield(L, tname); /* get metatable */
476 	    if (lua_rawequal(L, -1, -2)) /* MTs match? */
477 	    {
478 		lua_pop(L, 2); /* MTs */
479 		return p;
480 	    }
481 	}
482     }
483     return NULL;
484 }
485 
486     static void *
487 luaV_checkcache(lua_State *L, void *p)
488 {
489     luaV_getudata(L, p);
490     if (lua_isnil(L, -1)) luaL_error(L, "invalid object");
491     lua_pop(L, 1);
492     return p;
493 }
494 
495 #define luaV_unbox(L,luatyp,ud) (*((luatyp *) lua_touserdata((L),(ud))))
496 
497 #define luaV_checkvalid(L,luatyp,ud) \
498     luaV_checkcache((L), (void *) luaV_unbox((L),luatyp,(ud)))
499 
500     static void *
501 luaV_checkudata(lua_State *L, int ud, const char *tname)
502 {
503     void *p = luaV_toudata(L, ud, tname);
504     if (p == NULL) luaL_typeerror(L, ud, tname);
505     return p;
506 }
507 
508     static void
509 luaV_pushtypval(lua_State *L, typval_T *tv)
510 {
511     if (tv == NULL)
512     {
513 	lua_pushnil(L);
514 	return;
515     }
516     switch (tv->v_type)
517     {
518 	case VAR_STRING:
519 	    lua_pushstring(L, tv->vval.v_string == NULL
520 					    ? "" : (char *)tv->vval.v_string);
521 	    break;
522 	case VAR_NUMBER:
523 	    lua_pushinteger(L, (int) tv->vval.v_number);
524 	    break;
525 #ifdef FEAT_FLOAT
526 	case VAR_FLOAT:
527 	    lua_pushnumber(L, (lua_Number) tv->vval.v_float);
528 	    break;
529 #endif
530 	case VAR_LIST:
531 	    luaV_pushlist(L, tv->vval.v_list);
532 	    break;
533 	case VAR_DICT:
534 	    luaV_pushdict(L, tv->vval.v_dict);
535 	    break;
536 	case VAR_SPECIAL:
537 	    if (tv->vval.v_number <= VVAL_TRUE)
538 		lua_pushinteger(L, (int) tv->vval.v_number);
539 	    else
540 		lua_pushnil(L);
541 	    break;
542 	case VAR_FUNC:
543 	    luaV_pushfuncref(L, tv);
544 	    break;
545 	default:
546 	    lua_pushnil(L);
547     }
548 }
549 
550 /*
551  * Converts lua value at 'pos' to typval 'tv'.
552  * Returns OK or FAIL.
553  */
554     static int
555 luaV_totypval(lua_State *L, int pos, typval_T *tv)
556 {
557     int status = OK;
558 
559     switch (lua_type(L, pos))
560     {
561 	case LUA_TBOOLEAN:
562 	    tv->v_type = VAR_SPECIAL;
563 	    tv->vval.v_number = (varnumber_T) lua_toboolean(L, pos);
564 	    break;
565 	case LUA_TNIL:
566 	    tv->v_type = VAR_SPECIAL;
567 	    tv->vval.v_number = VVAL_NULL;
568 	    break;
569 	case LUA_TSTRING:
570 	    tv->v_type = VAR_STRING;
571 	    tv->vval.v_string = vim_strsave((char_u *) lua_tostring(L, pos));
572 	    break;
573 	case LUA_TNUMBER:
574 #ifdef FEAT_FLOAT
575 	    tv->v_type = VAR_FLOAT;
576 	    tv->vval.v_float = (float_T) lua_tonumber(L, pos);
577 #else
578 	    tv->v_type = VAR_NUMBER;
579 	    tv->vval.v_number = (varnumber_T) lua_tointeger(L, pos);
580 #endif
581 	    break;
582 	case LUA_TUSERDATA:
583 	{
584 	    void *p = lua_touserdata(L, pos);
585 
586 	    if (lua_getmetatable(L, pos)) /* has metatable? */
587 	    {
588 		/* check list */
589 		luaV_getfield(L, LUAVIM_LIST);
590 		if (lua_rawequal(L, -1, -2))
591 		{
592 		    tv->v_type = VAR_LIST;
593 		    tv->vval.v_list = *((luaV_List *) p);
594 		    ++tv->vval.v_list->lv_refcount;
595 		    lua_pop(L, 2); /* MTs */
596 		    break;
597 		}
598 		/* check dict */
599 		luaV_getfield(L, LUAVIM_DICT);
600 		if (lua_rawequal(L, -1, -3))
601 		{
602 		    tv->v_type = VAR_DICT;
603 		    tv->vval.v_dict = *((luaV_Dict *) p);
604 		    ++tv->vval.v_dict->dv_refcount;
605 		    lua_pop(L, 3); /* MTs */
606 		    break;
607 		}
608 		/* check funcref */
609 		luaV_getfield(L, LUAVIM_FUNCREF);
610 		if (lua_rawequal(L, -1, -4))
611 		{
612 		    luaV_Funcref *f = (luaV_Funcref *) p;
613 		    copy_tv(&f->tv, tv);
614 		    lua_pop(L, 4); /* MTs */
615 		    break;
616 		}
617 		lua_pop(L, 4); /* MTs */
618 	    }
619 	}
620 	/* FALLTHROUGH */
621 	default:
622 	    tv->v_type = VAR_NUMBER;
623 	    tv->vval.v_number = 0;
624 	    status = FAIL;
625     }
626     return status;
627 }
628 
629 /* similar to luaL_addlstring, but replaces \0 with \n if toline and
630  * \n with \0 otherwise */
631     static void
632 luaV_addlstring(luaL_Buffer *b, const char *s, size_t l, int toline)
633 {
634     while (l--)
635     {
636 	if (*s == '\0' && toline)
637 	    luaL_addchar(b, '\n');
638 	else if (*s == '\n' && !toline)
639 	    luaL_addchar(b, '\0');
640 	else
641 	    luaL_addchar(b, *s);
642 	s++;
643     }
644 }
645 
646     static void
647 luaV_pushline(lua_State *L, buf_T *buf, linenr_T n)
648 {
649     const char *s = (const char *) ml_get_buf(buf, n, FALSE);
650     luaL_Buffer b;
651     luaL_buffinit(L, &b);
652     luaV_addlstring(&b, s, strlen(s), 0);
653     luaL_pushresult(&b);
654 }
655 
656     static char_u *
657 luaV_toline(lua_State *L, int pos)
658 {
659     size_t l;
660     const char *s = lua_tolstring(L, pos, &l);
661 
662     luaL_Buffer b;
663     luaL_buffinit(L, &b);
664     luaV_addlstring(&b, s, l, 1);
665     luaL_pushresult(&b);
666     return (char_u *) lua_tostring(L, -1);
667 }
668 
669 /* pops a string s from the top of the stack and calls mf(t) for pieces t of
670  * s separated by newlines */
671     static void
672 luaV_msgfunc(lua_State *L, msgfunc_T mf)
673 {
674     luaL_Buffer b;
675     size_t l;
676     const char *p, *s = lua_tolstring(L, -1, &l);
677     luaL_buffinit(L, &b);
678     luaV_addlstring(&b, s, l, 0);
679     luaL_pushresult(&b);
680     /* break string */
681     p = s = lua_tolstring(L, -1, &l);
682     while (l--)
683     {
684 	if (*p++ == '\0') /* break? */
685 	{
686 	    mf((char_u *) s);
687 	    s = p;
688 	}
689     }
690     mf((char_u *) s);
691     lua_pop(L, 2); /* original and modified strings */
692 }
693 
694 #define luaV_newtype(typ,tname,luatyp,luatname) \
695 	static luatyp * \
696     luaV_new##tname (lua_State *L, typ *obj) \
697     { \
698 	luatyp *o = (luatyp *) lua_newuserdata(L, sizeof(luatyp)); \
699 	*o = obj; \
700 	luaV_setudata(L, obj); /* cache[obj] = udata */ \
701 	luaV_getfield(L, luatname); \
702 	lua_setmetatable(L, -2); \
703 	return o; \
704     }
705 
706 #define luaV_pushtype(typ,tname,luatyp) \
707 	static luatyp * \
708     luaV_push##tname(lua_State *L, typ *obj) \
709     { \
710 	luatyp *o = NULL; \
711 	if (obj == NULL) \
712 	    lua_pushnil(L); \
713 	else { \
714 	    luaV_getudata(L, obj); \
715 	    if (lua_isnil(L, -1)) /* not interned? */ \
716 	    { \
717 		lua_pop(L, 1); \
718 		o = luaV_new##tname(L, obj); \
719 	    } \
720 	    else \
721 		o = (luatyp *) lua_touserdata(L, -1); \
722 	} \
723 	return o; \
724     }
725 
726 #define luaV_type_tostring(tname,luatname) \
727 	static int \
728     luaV_##tname##_tostring (lua_State *L) \
729     { \
730 	lua_pushfstring(L, "%s: %p", luatname, lua_touserdata(L, 1)); \
731 	return 1; \
732     }
733 
734 /* =======   List type   ======= */
735 
736     static luaV_List *
737 luaV_newlist (lua_State *L, list_T *lis)
738 {
739     luaV_List *l = (luaV_List *) lua_newuserdata(L, sizeof(luaV_List));
740     *l = lis;
741     lis->lv_refcount++; /* reference in Lua */
742     luaV_setudata(L, lis); /* cache[lis] = udata */
743     luaV_getfield(L, LUAVIM_LIST);
744     lua_setmetatable(L, -2);
745     return l;
746 }
747 
748 luaV_pushtype(list_T, list, luaV_List)
749 luaV_type_tostring(list, LUAVIM_LIST)
750 
751     static int
752 luaV_list_len (lua_State *L)
753 {
754     list_T *l = luaV_unbox(L, luaV_List, 1);
755     lua_pushinteger(L, (l == NULL) ? 0 : (int) l->lv_len);
756     return 1;
757 }
758 
759     static int
760 luaV_list_iter (lua_State *L)
761 {
762     listitem_T *li = (listitem_T *) lua_touserdata(L, lua_upvalueindex(2));
763     if (li == NULL) return 0;
764     luaV_pushtypval(L, &li->li_tv);
765     lua_pushlightuserdata(L, (void *) li->li_next);
766     lua_replace(L, lua_upvalueindex(2));
767     return 1;
768 }
769 
770     static int
771 luaV_list_call (lua_State *L)
772 {
773     list_T *l = luaV_unbox(L, luaV_List, 1);
774     lua_pushvalue(L, lua_upvalueindex(1)); /* pass cache table along */
775     lua_pushlightuserdata(L, (void *) l->lv_first);
776     lua_pushcclosure(L, luaV_list_iter, 2);
777     return 1;
778 }
779 
780     static int
781 luaV_list_index (lua_State *L)
782 {
783     list_T *l = luaV_unbox(L, luaV_List, 1);
784     if (lua_isnumber(L, 2)) /* list item? */
785     {
786 	listitem_T *li = list_find(l, (long) luaL_checkinteger(L, 2));
787 	if (li == NULL)
788 	    lua_pushnil(L);
789 	else
790 	    luaV_pushtypval(L, &li->li_tv);
791     }
792     else if (lua_isstring(L, 2)) /* method? */
793     {
794 	const char *s = lua_tostring(L, 2);
795 	if (strncmp(s, "add", 3) == 0
796 		|| strncmp(s, "insert", 6) == 0)
797 	{
798 	    lua_getmetatable(L, 1);
799 	    lua_getfield(L, -1, s);
800 	}
801 	else
802 	    lua_pushnil(L);
803     }
804     else
805 	lua_pushnil(L);
806     return 1;
807 }
808 
809     static int
810 luaV_list_newindex (lua_State *L)
811 {
812     list_T *l = luaV_unbox(L, luaV_List, 1);
813     long n = (long) luaL_checkinteger(L, 2);
814     listitem_T *li;
815     if (l->lv_lock)
816 	luaL_error(L, "list is locked");
817     li = list_find(l, n);
818     if (li == NULL) return 0;
819     if (lua_isnil(L, 3)) /* remove? */
820     {
821 	vimlist_remove(l, li, li);
822 	clear_tv(&li->li_tv);
823 	vim_free(li);
824     }
825     else
826     {
827 	typval_T v;
828 	luaV_checktypval(L, 3, &v, "setting list item");
829 	clear_tv(&li->li_tv);
830 	copy_tv(&v, &li->li_tv);
831 	clear_tv(&v);
832     }
833     return 0;
834 }
835 
836     static int
837 luaV_list_add (lua_State *L)
838 {
839     luaV_List *lis = luaV_checkudata(L, 1, LUAVIM_LIST);
840     list_T *l = (list_T *) luaV_checkcache(L, (void *) *lis);
841     typval_T v;
842     if (l->lv_lock)
843 	luaL_error(L, "list is locked");
844     lua_settop(L, 2);
845     luaV_checktypval(L, 2, &v, "adding list item");
846     if (list_append_tv(l, &v) == FAIL)
847     {
848 	clear_tv(&v);
849 	luaL_error(L, "failed to add item to list");
850     }
851     clear_tv(&v);
852     lua_settop(L, 1);
853     return 1;
854 }
855 
856     static int
857 luaV_list_insert (lua_State *L)
858 {
859     luaV_List *lis = luaV_checkudata(L, 1, LUAVIM_LIST);
860     list_T *l = (list_T *) luaV_checkcache(L, (void *) *lis);
861     long pos = (long) luaL_optinteger(L, 3, 0);
862     listitem_T *li = NULL;
863     typval_T v;
864     if (l->lv_lock)
865 	luaL_error(L, "list is locked");
866     if (pos < l->lv_len)
867     {
868 	li = list_find(l, pos);
869 	if (li == NULL)
870 	    luaL_error(L, "invalid position");
871     }
872     lua_settop(L, 2);
873     luaV_checktypval(L, 2, &v, "inserting list item");
874     if (list_insert_tv(l, &v, li) == FAIL)
875     {
876 	clear_tv(&v);
877 	luaL_error(L, "failed to add item to list");
878     }
879     clear_tv(&v);
880     lua_settop(L, 1);
881     return 1;
882 }
883 
884 static const luaL_Reg luaV_List_mt[] = {
885     {"__tostring", luaV_list_tostring},
886     {"__len", luaV_list_len},
887     {"__call", luaV_list_call},
888     {"__index", luaV_list_index},
889     {"__newindex", luaV_list_newindex},
890     {"add", luaV_list_add},
891     {"insert", luaV_list_insert},
892     {NULL, NULL}
893 };
894 
895 
896 /* =======   Dict type   ======= */
897 
898     static luaV_Dict *
899 luaV_newdict (lua_State *L, dict_T *dic)
900 {
901     luaV_Dict *d = (luaV_Dict *) lua_newuserdata(L, sizeof(luaV_Dict));
902     *d = dic;
903     dic->dv_refcount++; /* reference in Lua */
904     luaV_setudata(L, dic); /* cache[dic] = udata */
905     luaV_getfield(L, LUAVIM_DICT);
906     lua_setmetatable(L, -2);
907     return d;
908 }
909 
910 luaV_pushtype(dict_T, dict, luaV_Dict)
911 luaV_type_tostring(dict, LUAVIM_DICT)
912 
913     static int
914 luaV_dict_len (lua_State *L)
915 {
916     dict_T *d = luaV_unbox(L, luaV_Dict, 1);
917     lua_pushinteger(L, (d == NULL) ? 0 : (int) d->dv_hashtab.ht_used);
918     return 1;
919 }
920 
921     static int
922 luaV_dict_iter (lua_State *L UNUSED)
923 {
924 #ifdef FEAT_EVAL
925     hashitem_T *hi = (hashitem_T *) lua_touserdata(L, lua_upvalueindex(2));
926     int n = lua_tointeger(L, lua_upvalueindex(3));
927     dictitem_T *di;
928     if (n <= 0) return 0;
929     while (HASHITEM_EMPTY(hi)) hi++;
930     di = dict_lookup(hi);
931     lua_pushstring(L, (char *) hi->hi_key);
932     luaV_pushtypval(L, &di->di_tv);
933     lua_pushlightuserdata(L, (void *) (hi + 1));
934     lua_replace(L, lua_upvalueindex(2));
935     lua_pushinteger(L, n - 1);
936     lua_replace(L, lua_upvalueindex(3));
937     return 2;
938 #else
939     return 0;
940 #endif
941 }
942 
943     static int
944 luaV_dict_call (lua_State *L)
945 {
946     dict_T *d = luaV_unbox(L, luaV_Dict, 1);
947     hashtab_T *ht = &d->dv_hashtab;
948     lua_pushvalue(L, lua_upvalueindex(1)); /* pass cache table along */
949     lua_pushlightuserdata(L, (void *) ht->ht_array);
950     lua_pushinteger(L, ht->ht_used); /* # remaining items */
951     lua_pushcclosure(L, luaV_dict_iter, 3);
952     return 1;
953 }
954 
955     static int
956 luaV_dict_index(lua_State *L)
957 {
958     dict_T *d = luaV_unbox(L, luaV_Dict, 1);
959     char_u *key = (char_u *) luaL_checkstring(L, 2);
960     dictitem_T *di = dict_find(d, key, -1);
961 
962     if (di == NULL)
963 	lua_pushnil(L);
964     else
965     {
966 	luaV_pushtypval(L, &di->di_tv);
967 	if (di->di_tv.v_type == VAR_FUNC) /* funcref? */
968 	{
969 	    luaV_Funcref *f = (luaV_Funcref *) lua_touserdata(L, -1);
970 	    f->self = d; /* keep "self" reference */
971 	    d->dv_refcount++;
972 	}
973     }
974     return 1;
975 }
976 
977     static int
978 luaV_dict_newindex(lua_State *L)
979 {
980     dict_T *d = luaV_unbox(L, luaV_Dict, 1);
981     char_u *key = (char_u *) luaL_checkstring(L, 2);
982     dictitem_T *di;
983     typval_T v;
984     if (d->dv_lock)
985 	luaL_error(L, "dict is locked");
986     if (key == NULL)
987 	return 0;
988     if (*key == NUL)
989 	luaL_error(L, "empty key");
990     if (!lua_isnil(L, 3)) /* read value? */
991     {
992 	luaV_checktypval(L, 3, &v, "setting dict item");
993 	if (d->dv_scope == VAR_DEF_SCOPE && v.v_type == VAR_FUNC)
994 	    luaL_error(L, "cannot assign funcref to builtin scope");
995     }
996     di = dict_find(d, key, -1);
997     if (di == NULL) /* non-existing key? */
998     {
999 	if (lua_isnil(L, 3))
1000 	    return 0;
1001 	di = dictitem_alloc(key);
1002 	if (di == NULL)
1003 	    return 0;
1004 	if (dict_add(d, di) == FAIL)
1005 	{
1006 	    vim_free(di);
1007 	    return 0;
1008 	}
1009     }
1010     else
1011 	clear_tv(&di->di_tv);
1012     if (lua_isnil(L, 3)) /* remove? */
1013     {
1014 	hashitem_T *hi = hash_find(&d->dv_hashtab, di->di_key);
1015 	hash_remove(&d->dv_hashtab, hi);
1016 	dictitem_free(di);
1017     }
1018     else
1019     {
1020 	copy_tv(&v, &di->di_tv);
1021 	clear_tv(&v);
1022     }
1023     return 0;
1024 }
1025 
1026 static const luaL_Reg luaV_Dict_mt[] = {
1027     {"__tostring", luaV_dict_tostring},
1028     {"__len", luaV_dict_len},
1029     {"__call", luaV_dict_call},
1030     {"__index", luaV_dict_index},
1031     {"__newindex", luaV_dict_newindex},
1032     {NULL, NULL}
1033 };
1034 
1035 
1036 /* =======   Funcref type   ======= */
1037 
1038     static luaV_Funcref *
1039 luaV_newfuncref(lua_State *L, char_u *name)
1040 {
1041     luaV_Funcref *f = (luaV_Funcref *)lua_newuserdata(L, sizeof(luaV_Funcref));
1042 
1043     if (name != NULL)
1044     {
1045 	func_ref(name); /* as in copy_tv */
1046 	f->tv.vval.v_string = vim_strsave(name);
1047     }
1048     f->tv.v_type = VAR_FUNC;
1049     f->args.v_type = VAR_LIST;
1050     f->self = NULL;
1051     luaV_getfield(L, LUAVIM_FUNCREF);
1052     lua_setmetatable(L, -2);
1053     return f;
1054 }
1055 
1056     static luaV_Funcref *
1057 luaV_pushfuncref(lua_State *L, typval_T *tv)
1058 {
1059     luaV_Funcref *f = luaV_newfuncref(L, NULL);
1060     copy_tv(tv, &f->tv);
1061     clear_tv(tv);
1062     return f;
1063 }
1064 
1065 
1066 luaV_type_tostring(funcref, LUAVIM_FUNCREF)
1067 
1068     static int
1069 luaV_funcref_gc(lua_State *L)
1070 {
1071     luaV_Funcref *f = (luaV_Funcref *) lua_touserdata(L, 1);
1072 
1073     func_unref(f->tv.vval.v_string);
1074     vim_free(f->tv.vval.v_string);
1075     dict_unref(f->self);
1076     return 0;
1077 }
1078 
1079 /* equivalent to string(funcref) */
1080     static int
1081 luaV_funcref_len(lua_State *L)
1082 {
1083     luaV_Funcref *f = (luaV_Funcref *) lua_touserdata(L, 1);
1084 
1085     lua_pushstring(L, (const char *) f->tv.vval.v_string);
1086     return 1;
1087 }
1088 
1089     static int
1090 luaV_funcref_call(lua_State *L)
1091 {
1092     luaV_Funcref *f = (luaV_Funcref *) lua_touserdata(L, 1);
1093     int i, n = lua_gettop(L) - 1; /* #args */
1094     int status;
1095     typval_T v, rettv;
1096 
1097     f->args.vval.v_list = list_alloc();
1098     rettv.v_type = VAR_UNKNOWN; /* as in clear_tv */
1099     if (f->args.vval.v_list == NULL)
1100 	status = FAIL;
1101     else
1102     {
1103 	for (i = 0; i < n; i++)
1104 	{
1105 	    luaV_checktypval(L, i + 2, &v, "calling funcref");
1106 	    list_append_tv(f->args.vval.v_list, &v);
1107 	}
1108 	status = func_call(f->tv.vval.v_string, &f->args,
1109 							NULL, f->self, &rettv);
1110 	if (status == OK)
1111 	    luaV_pushtypval(L, &rettv);
1112 	clear_tv(&f->args);
1113 	clear_tv(&rettv);
1114     }
1115     if (status != OK)
1116 	luaL_error(L, "cannot call funcref");
1117     return 1;
1118 }
1119 
1120 static const luaL_Reg luaV_Funcref_mt[] = {
1121     {"__tostring", luaV_funcref_tostring},
1122     {"__gc", luaV_funcref_gc},
1123     {"__len", luaV_funcref_len},
1124     {"__call", luaV_funcref_call},
1125     {NULL, NULL}
1126 };
1127 
1128 
1129 /* =======   Buffer type   ======= */
1130 
1131 luaV_newtype(buf_T, buffer, luaV_Buffer, LUAVIM_BUFFER)
1132 luaV_pushtype(buf_T, buffer, luaV_Buffer)
1133 luaV_type_tostring(buffer, LUAVIM_BUFFER)
1134 
1135     static int
1136 luaV_buffer_len(lua_State *L)
1137 {
1138     buf_T *b = (buf_T *) luaV_checkvalid(L, luaV_Buffer, 1);
1139     lua_pushinteger(L, b->b_ml.ml_line_count);
1140     return 1;
1141 }
1142 
1143     static int
1144 luaV_buffer_call(lua_State *L)
1145 {
1146     buf_T *b = (buf_T *) luaV_checkvalid(L, luaV_Buffer, 1);
1147     lua_settop(L, 1);
1148     set_curbuf(b, DOBUF_SPLIT);
1149     return 1;
1150 }
1151 
1152     static int
1153 luaV_buffer_index(lua_State *L)
1154 {
1155     buf_T *b = (buf_T *) luaV_checkvalid(L, luaV_Buffer, 1);
1156     linenr_T n = (linenr_T) lua_tointeger(L, 2);
1157     if (n > 0 && n <= b->b_ml.ml_line_count)
1158 	luaV_pushline(L, b, n);
1159     else if (lua_isstring(L, 2))
1160     {
1161 	const char *s = lua_tostring(L, 2);
1162 	if (strncmp(s, "name", 4) == 0)
1163 	    lua_pushstring(L, (b->b_sfname == NULL)
1164 					? "" : (char *) b->b_sfname);
1165 	else if (strncmp(s, "fname", 5) == 0)
1166 	    lua_pushstring(L, (b->b_ffname == NULL)
1167 					? "" : (char *) b->b_ffname);
1168 	else if (strncmp(s, "number", 6) == 0)
1169 	    lua_pushinteger(L, b->b_fnum);
1170 	/* methods */
1171 	else if (strncmp(s,   "insert", 6) == 0
1172 		|| strncmp(s, "next", 4) == 0
1173 		|| strncmp(s, "previous", 8) == 0
1174 		|| strncmp(s, "isvalid", 7) == 0)
1175 	{
1176 	    lua_getmetatable(L, 1);
1177 	    lua_getfield(L, -1, s);
1178 	}
1179 	else
1180 	    lua_pushnil(L);
1181     }
1182     else
1183 	lua_pushnil(L);
1184     return 1;
1185 }
1186 
1187     static int
1188 luaV_buffer_newindex(lua_State *L)
1189 {
1190     buf_T *b = (buf_T *) luaV_checkvalid(L, luaV_Buffer, 1);
1191     linenr_T n = (linenr_T) luaL_checkinteger(L, 2);
1192 #ifdef HAVE_SANDBOX
1193     luaV_checksandbox(L);
1194 #endif
1195     if (n < 1 || n > b->b_ml.ml_line_count)
1196 	luaL_error(L, "invalid line number");
1197     if (lua_isnil(L, 3)) /* delete line */
1198     {
1199 	buf_T *buf = curbuf;
1200 	curbuf = b;
1201 	if (u_savedel(n, 1L) == FAIL)
1202 	{
1203 	    curbuf = buf;
1204 	    luaL_error(L, "cannot save undo information");
1205 	}
1206 	else if (ml_delete(n, FALSE) == FAIL)
1207 	{
1208 	    curbuf = buf;
1209 	    luaL_error(L, "cannot delete line");
1210 	}
1211 	else
1212 	{
1213 	    deleted_lines_mark(n, 1L);
1214 	    if (b == curwin->w_buffer) /* fix cursor in current window? */
1215 	    {
1216 		if (curwin->w_cursor.lnum >= n)
1217 		{
1218 		    if (curwin->w_cursor.lnum > n)
1219 		    {
1220 			curwin->w_cursor.lnum -= 1;
1221 			check_cursor_col();
1222 		    }
1223 		    else check_cursor();
1224 		    changed_cline_bef_curs();
1225 		}
1226 		invalidate_botline();
1227 	    }
1228 	}
1229 	curbuf = buf;
1230     }
1231     else if (lua_isstring(L, 3)) /* update line */
1232     {
1233 	buf_T *buf = curbuf;
1234 	curbuf = b;
1235 	if (u_savesub(n) == FAIL)
1236 	{
1237 	    curbuf = buf;
1238 	    luaL_error(L, "cannot save undo information");
1239 	}
1240 	else if (ml_replace(n, luaV_toline(L, 3), TRUE) == FAIL)
1241 	{
1242 	    curbuf = buf;
1243 	    luaL_error(L, "cannot replace line");
1244 	}
1245 	else changed_bytes(n, 0);
1246 	curbuf = buf;
1247 	if (b == curwin->w_buffer)
1248 	    check_cursor_col();
1249     }
1250     else
1251 	luaL_error(L, "wrong argument to change line");
1252     return 0;
1253 }
1254 
1255     static int
1256 luaV_buffer_insert(lua_State *L)
1257 {
1258     luaV_Buffer *lb = luaV_checkudata(L, 1, LUAVIM_BUFFER);
1259     buf_T *b = (buf_T *) luaV_checkcache(L, (void *) *lb);
1260     linenr_T last = b->b_ml.ml_line_count;
1261     linenr_T n = (linenr_T) luaL_optinteger(L, 3, last);
1262     buf_T *buf;
1263     luaL_checktype(L, 2, LUA_TSTRING);
1264 #ifdef HAVE_SANDBOX
1265     luaV_checksandbox(L);
1266 #endif
1267     /* fix insertion line */
1268     if (n < 0) n = 0;
1269     if (n > last) n = last;
1270     /* insert */
1271     buf = curbuf;
1272     curbuf = b;
1273     if (u_save(n, n + 1) == FAIL)
1274     {
1275 	curbuf = buf;
1276 	luaL_error(L, "cannot save undo information");
1277     }
1278     else if (ml_append(n, luaV_toline(L, 2), 0, FALSE) == FAIL)
1279     {
1280 	curbuf = buf;
1281 	luaL_error(L, "cannot insert line");
1282     }
1283     else
1284 	appended_lines_mark(n, 1L);
1285     curbuf = buf;
1286     update_screen(VALID);
1287     return 0;
1288 }
1289 
1290     static int
1291 luaV_buffer_next(lua_State *L)
1292 {
1293     luaV_Buffer *b = luaV_checkudata(L, 1, LUAVIM_BUFFER);
1294     buf_T *buf = (buf_T *) luaV_checkcache(L, (void *) *b);
1295     luaV_pushbuffer(L, buf->b_next);
1296     return 1;
1297 }
1298 
1299     static int
1300 luaV_buffer_previous(lua_State *L)
1301 {
1302     luaV_Buffer *b = luaV_checkudata(L, 1, LUAVIM_BUFFER);
1303     buf_T *buf = (buf_T *) luaV_checkcache(L, (void *) *b);
1304     luaV_pushbuffer(L, buf->b_prev);
1305     return 1;
1306 }
1307 
1308     static int
1309 luaV_buffer_isvalid(lua_State *L)
1310 {
1311     luaV_Buffer *b = luaV_checkudata(L, 1, LUAVIM_BUFFER);
1312     luaV_getudata(L, *b);
1313     lua_pushboolean(L, !lua_isnil(L, -1));
1314     return 1;
1315 }
1316 
1317 static const luaL_Reg luaV_Buffer_mt[] = {
1318     {"__tostring", luaV_buffer_tostring},
1319     {"__len", luaV_buffer_len},
1320     {"__call", luaV_buffer_call},
1321     {"__index", luaV_buffer_index},
1322     {"__newindex", luaV_buffer_newindex},
1323     {"insert", luaV_buffer_insert},
1324     {"next", luaV_buffer_next},
1325     {"previous", luaV_buffer_previous},
1326     {"isvalid", luaV_buffer_isvalid},
1327     {NULL, NULL}
1328 };
1329 
1330 
1331 /* =======   Window type   ======= */
1332 
1333 luaV_newtype(win_T, window, luaV_Window, LUAVIM_WINDOW)
1334 luaV_pushtype(win_T, window, luaV_Window)
1335 luaV_type_tostring(window, LUAVIM_WINDOW)
1336 
1337     static int
1338 luaV_window_call(lua_State *L)
1339 {
1340     win_T *w = (win_T *) luaV_checkvalid(L, luaV_Window, 1);
1341     lua_settop(L, 1);
1342     win_goto(w);
1343     return 1;
1344 }
1345 
1346     static int
1347 luaV_window_index(lua_State *L)
1348 {
1349     win_T *w = (win_T *) luaV_checkvalid(L, luaV_Window, 1);
1350     const char *s = luaL_checkstring(L, 2);
1351     if (strncmp(s, "buffer", 6) == 0)
1352 	luaV_pushbuffer(L, w->w_buffer);
1353     else if (strncmp(s, "line", 4) == 0)
1354 	lua_pushinteger(L, w->w_cursor.lnum);
1355     else if (strncmp(s, "col", 3) == 0)
1356 	lua_pushinteger(L, w->w_cursor.col + 1);
1357     else if (strncmp(s, "width", 5) == 0)
1358 	lua_pushinteger(L, w->w_width);
1359     else if (strncmp(s, "height", 6) == 0)
1360 	lua_pushinteger(L, w->w_height);
1361     /* methods */
1362     else if (strncmp(s,   "next", 4) == 0
1363 	    || strncmp(s, "previous", 8) == 0
1364 	    || strncmp(s, "isvalid", 7) == 0)
1365     {
1366 	lua_getmetatable(L, 1);
1367 	lua_getfield(L, -1, s);
1368     }
1369     else
1370 	lua_pushnil(L);
1371     return 1;
1372 }
1373 
1374     static int
1375 luaV_window_newindex (lua_State *L)
1376 {
1377     win_T *w = (win_T *) luaV_checkvalid(L, luaV_Window, 1);
1378     const char *s = luaL_checkstring(L, 2);
1379     int v = luaL_checkinteger(L, 3);
1380     if (strncmp(s, "line", 4) == 0)
1381     {
1382 #ifdef HAVE_SANDBOX
1383 	luaV_checksandbox(L);
1384 #endif
1385 	if (v < 1 || v > w->w_buffer->b_ml.ml_line_count)
1386 	    luaL_error(L, "line out of range");
1387 	w->w_cursor.lnum = v;
1388 	update_screen(VALID);
1389     }
1390     else if (strncmp(s, "col", 3) == 0)
1391     {
1392 #ifdef HAVE_SANDBOX
1393 	luaV_checksandbox(L);
1394 #endif
1395 	w->w_cursor.col = v - 1;
1396 	w->w_set_curswant = TRUE;
1397 	update_screen(VALID);
1398     }
1399     else if (strncmp(s, "width", 5) == 0)
1400     {
1401 	win_T *win = curwin;
1402 #ifdef FEAT_GUI
1403 	need_mouse_correct = TRUE;
1404 #endif
1405 	curwin = w;
1406 	win_setwidth(v);
1407 	curwin = win;
1408     }
1409     else if (strncmp(s, "height", 6) == 0)
1410     {
1411 	win_T *win = curwin;
1412 #ifdef FEAT_GUI
1413 	need_mouse_correct = TRUE;
1414 #endif
1415 	curwin = w;
1416 	win_setheight(v);
1417 	curwin = win;
1418     }
1419     else
1420 	luaL_error(L, "invalid window property: `%s'", s);
1421     return 0;
1422 }
1423 
1424     static int
1425 luaV_window_next(lua_State *L)
1426 {
1427     luaV_Window *w = luaV_checkudata(L, 1, LUAVIM_WINDOW);
1428     win_T *win = (win_T *) luaV_checkcache(L, (void *) *w);
1429     luaV_pushwindow(L, win->w_next);
1430     return 1;
1431 }
1432 
1433     static int
1434 luaV_window_previous(lua_State *L)
1435 {
1436     luaV_Window *w = luaV_checkudata(L, 1, LUAVIM_WINDOW);
1437     win_T *win = (win_T *) luaV_checkcache(L, (void *) *w);
1438     luaV_pushwindow(L, win->w_prev);
1439     return 1;
1440 }
1441 
1442     static int
1443 luaV_window_isvalid(lua_State *L)
1444 {
1445     luaV_Window *w = luaV_checkudata(L, 1, LUAVIM_WINDOW);
1446     luaV_getudata(L, *w);
1447     lua_pushboolean(L, !lua_isnil(L, -1));
1448     return 1;
1449 }
1450 
1451 static const luaL_Reg luaV_Window_mt[] = {
1452     {"__tostring", luaV_window_tostring},
1453     {"__call", luaV_window_call},
1454     {"__index", luaV_window_index},
1455     {"__newindex", luaV_window_newindex},
1456     {"next", luaV_window_next},
1457     {"previous", luaV_window_previous},
1458     {"isvalid", luaV_window_isvalid},
1459     {NULL, NULL}
1460 };
1461 
1462 
1463 /* =======   Vim module   ======= */
1464 
1465     static int
1466 luaV_print(lua_State *L)
1467 {
1468     int i, n = lua_gettop(L); /* nargs */
1469     const char *s;
1470     size_t l;
1471     luaL_Buffer b;
1472     luaL_buffinit(L, &b);
1473     lua_getglobal(L, "tostring");
1474     for (i = 1; i <= n; i++)
1475     {
1476 	lua_pushvalue(L, -1); /* tostring */
1477 	lua_pushvalue(L, i); /* arg */
1478 	lua_call(L, 1, 1);
1479 	s = lua_tolstring(L, -1, &l);
1480 	if (s == NULL)
1481 	    return luaL_error(L, "cannot convert to string");
1482 	if (i > 1) luaL_addchar(&b, ' '); /* use space instead of tab */
1483 	luaV_addlstring(&b, s, l, 0);
1484 	lua_pop(L, 1);
1485     }
1486     luaL_pushresult(&b);
1487     luaV_msg(L);
1488     return 0;
1489 }
1490 
1491     static int
1492 luaV_debug(lua_State *L)
1493 {
1494     lua_settop(L, 0);
1495     lua_getglobal(L, "vim");
1496     lua_getfield(L, -1, "eval");
1497     lua_remove(L, -2); /* vim.eval at position 1 */
1498     for (;;)
1499     {
1500 	const char *input;
1501 	size_t l;
1502 	lua_pushvalue(L, 1); /* vim.eval */
1503 	lua_pushliteral(L, "input('lua_debug> ')");
1504 	lua_call(L, 1, 1); /* return string */
1505 	input = lua_tolstring(L, -1, &l);
1506 	if (l == 0 || strcmp(input, "cont") == 0)
1507 	    return 0;
1508 	msg_putchar('\n'); /* avoid outputting on input line */
1509 	if (luaL_loadbuffer(L, input, l, "=(debug command)")
1510 		|| lua_pcall(L, 0, 0, 0))
1511 	    luaV_emsg(L);
1512 	lua_settop(L, 1); /* remove eventual returns, but keep vim.eval */
1513     }
1514 }
1515 
1516     static int
1517 luaV_command(lua_State *L)
1518 {
1519     do_cmdline_cmd((char_u *) luaL_checkstring(L, 1));
1520     update_screen(VALID);
1521     return 0;
1522 }
1523 
1524     static int
1525 luaV_eval(lua_State *L)
1526 {
1527     typval_T *tv = eval_expr((char_u *) luaL_checkstring(L, 1), NULL);
1528     if (tv == NULL) luaL_error(L, "invalid expression");
1529     luaV_pushtypval(L, tv);
1530     free_tv(tv);
1531     return 1;
1532 }
1533 
1534     static int
1535 luaV_beep(lua_State *L UNUSED)
1536 {
1537     vim_beep(BO_LANG);
1538     return 0;
1539 }
1540 
1541     static int
1542 luaV_line(lua_State *L)
1543 {
1544     luaV_pushline(L, curbuf, curwin->w_cursor.lnum);
1545     return 1;
1546 }
1547 
1548     static int
1549 luaV_list(lua_State *L)
1550 {
1551     list_T *l;
1552     int initarg = !lua_isnoneornil(L, 1);
1553 
1554     if (initarg && lua_type(L, 1) != LUA_TTABLE)
1555 	luaL_error(L, "table expected, got %s", luaL_typename(L, 1));
1556     l = list_alloc();
1557     if (l == NULL)
1558 	lua_pushnil(L);
1559     else
1560     {
1561 	luaV_newlist(L, l);
1562 	if (initarg) /* traverse table to init list */
1563 	{
1564 	    int notnil, i = 0;
1565 	    typval_T v;
1566 	    do
1567 	    {
1568 		lua_rawgeti(L, 1, ++i);
1569 		notnil = !lua_isnil(L, -1);
1570 		if (notnil)
1571 		{
1572 		    luaV_checktypval(L, -1, &v, "vim.list");
1573 		    list_append_tv(l, &v);
1574 		}
1575 		lua_pop(L, 1); /* value */
1576 	    } while (notnil);
1577 	}
1578     }
1579     return 1;
1580 }
1581 
1582     static int
1583 luaV_dict(lua_State *L)
1584 {
1585     dict_T *d;
1586     int initarg = !lua_isnoneornil(L, 1);
1587 
1588     if (initarg && lua_type(L, 1) != LUA_TTABLE)
1589 	luaL_error(L, "table expected, got %s", luaL_typename(L, 1));
1590     d = dict_alloc();
1591     if (d == NULL)
1592 	lua_pushnil(L);
1593     else
1594     {
1595 	luaV_newdict(L, d);
1596 	if (initarg) /* traverse table to init dict */
1597 	{
1598 	    lua_pushnil(L);
1599 	    while (lua_next(L, 1))
1600 	    {
1601 		char_u *key;
1602 		dictitem_T *di;
1603 		typval_T v;
1604 
1605 		lua_pushvalue(L, -2); /* dup key in case it's a number */
1606 		key = (char_u *) lua_tostring(L, -1);
1607 		if (key == NULL)
1608 		{
1609 		    lua_pushnil(L);
1610 		    return 1;
1611 		}
1612 		if (*key == NUL)
1613 		    luaL_error(L, "table has empty key");
1614 		luaV_checktypval(L, -2, &v, "vim.dict"); /* value */
1615 		di = dictitem_alloc(key);
1616 		if (di == NULL || dict_add(d, di) == FAIL)
1617 		{
1618 		    vim_free(di);
1619 		    lua_pushnil(L);
1620 		    return 1;
1621 		}
1622 		copy_tv(&v, &di->di_tv);
1623 		clear_tv(&v);
1624 		lua_pop(L, 2); /* key copy and value */
1625 	    }
1626 	}
1627     }
1628     return 1;
1629 }
1630 
1631     static int
1632 luaV_funcref(lua_State *L)
1633 {
1634     const char *name = luaL_checkstring(L, 1);
1635     /* note: not checking if function exists (needs function_exists) */
1636     if (name == NULL || *name == NUL || VIM_ISDIGIT(*name))
1637 	luaL_error(L, "invalid function name: %s", name);
1638     luaV_newfuncref(L, (char_u *) name);
1639     return 1;
1640 }
1641 
1642     static int
1643 luaV_buffer(lua_State *L)
1644 {
1645     buf_T *buf;
1646     if (lua_isstring(L, 1)) /* get by number or name? */
1647     {
1648 	if (lua_isnumber(L, 1)) /* by number? */
1649 	{
1650 	    int n = lua_tointeger(L, 1);
1651 	    FOR_ALL_BUFFERS(buf)
1652 		if (buf->b_fnum == n) break;
1653 	}
1654 	else // by name
1655 	{
1656 	    size_t l;
1657 	    const char *s = lua_tolstring(L, 1, &l);
1658 	    FOR_ALL_BUFFERS(buf)
1659 	    {
1660 		if (buf->b_ffname == NULL || buf->b_sfname == NULL)
1661 		{
1662 		    if (l == 0) break;
1663 		}
1664 		else if (strncmp(s, (char *)buf->b_ffname, l) == 0
1665 			|| strncmp(s, (char *)buf->b_sfname, l) == 0)
1666 		    break;
1667 	    }
1668 	}
1669     }
1670     else
1671 	buf = (lua_toboolean(L, 1)) ? firstbuf : curbuf; /* first buffer? */
1672     luaV_pushbuffer(L, buf);
1673     return 1;
1674 }
1675 
1676     static int
1677 luaV_window(lua_State *L)
1678 {
1679     win_T *win;
1680     if (lua_isnumber(L, 1)) /* get by number? */
1681     {
1682 	int n = lua_tointeger(L, 1);
1683 	for (win = firstwin; win != NULL; win = win->w_next, n--)
1684 	    if (n == 1) break;
1685     }
1686     else
1687 	win = (lua_toboolean(L, 1)) ? firstwin : curwin; /* first window? */
1688     luaV_pushwindow(L, win);
1689     return 1;
1690 }
1691 
1692     static int
1693 luaV_open(lua_State *L)
1694 {
1695     char_u *s = NULL;
1696 #ifdef HAVE_SANDBOX
1697     luaV_checksandbox(L);
1698 #endif
1699     if (lua_isstring(L, 1)) s = (char_u *) lua_tostring(L, 1);
1700     luaV_pushbuffer(L, buflist_new(s, NULL, 1L, BLN_LISTED));
1701     return 1;
1702 }
1703 
1704     static int
1705 luaV_type(lua_State *L)
1706 {
1707     luaL_checkany(L, 1);
1708     if (lua_type(L, 1) == LUA_TUSERDATA) /* check vim udata? */
1709     {
1710 	lua_settop(L, 1);
1711 	if (lua_getmetatable(L, 1))
1712 	{
1713 	    luaV_getfield(L, LUAVIM_LIST);
1714 	    if (lua_rawequal(L, -1, 2))
1715 	    {
1716 		lua_pushstring(L, "list");
1717 		return 1;
1718 	    }
1719 	    luaV_getfield(L, LUAVIM_DICT);
1720 	    if (lua_rawequal(L, -1, 2))
1721 	    {
1722 		lua_pushstring(L, "dict");
1723 		return 1;
1724 	    }
1725 	    luaV_getfield(L, LUAVIM_FUNCREF);
1726 	    if (lua_rawequal(L, -1, 2))
1727 	    {
1728 		lua_pushstring(L, "funcref");
1729 		return 1;
1730 	    }
1731 	    luaV_getfield(L, LUAVIM_BUFFER);
1732 	    if (lua_rawequal(L, -1, 2))
1733 	    {
1734 		lua_pushstring(L, "buffer");
1735 		return 1;
1736 	    }
1737 	    luaV_getfield(L, LUAVIM_WINDOW);
1738 	    if (lua_rawequal(L, -1, 2))
1739 	    {
1740 		lua_pushstring(L, "window");
1741 		return 1;
1742 	    }
1743 	}
1744     }
1745     lua_pushstring(L, luaL_typename(L, 1)); /* fallback */
1746     return 1;
1747 }
1748 
1749 static const luaL_Reg luaV_module[] = {
1750     {"command", luaV_command},
1751     {"eval", luaV_eval},
1752     {"beep", luaV_beep},
1753     {"line", luaV_line},
1754     {"list", luaV_list},
1755     {"dict", luaV_dict},
1756     {"funcref", luaV_funcref},
1757     {"buffer", luaV_buffer},
1758     {"window", luaV_window},
1759     {"open", luaV_open},
1760     {"type", luaV_type},
1761     {NULL, NULL}
1762 };
1763 
1764 /* for freeing list, dict, buffer and window objects; lightuserdata as arg */
1765     static int
1766 luaV_free(lua_State *L)
1767 {
1768     lua_pushnil(L);
1769     luaV_setudata(L, lua_touserdata(L, 1));
1770     return 0;
1771 }
1772 
1773     static int
1774 luaV_luaeval (lua_State *L)
1775 {
1776     luaL_Buffer b;
1777     size_t l;
1778     const char *str = lua_tolstring(L, 1, &l);
1779     typval_T *arg = (typval_T *) lua_touserdata(L, 2);
1780     typval_T *rettv = (typval_T *) lua_touserdata(L, 3);
1781     luaL_buffinit(L, &b);
1782     luaL_addlstring(&b, LUAVIM_EVALHEADER, sizeof(LUAVIM_EVALHEADER) - 1);
1783     luaL_addlstring(&b, str, l);
1784     luaL_pushresult(&b);
1785     str = lua_tolstring(L, -1, &l);
1786     if (luaL_loadbuffer(L, str, l, LUAVIM_EVALNAME)) /* compile error? */
1787     {
1788 	luaV_emsg(L);
1789 	return 0;
1790     }
1791     luaV_pushtypval(L, arg);
1792     if (lua_pcall(L, 1, 1, 0)) /* running error? */
1793     {
1794 	luaV_emsg(L);
1795 	return 0;
1796     }
1797     if (luaV_totypval(L, -1, rettv) == FAIL)
1798 	emsg("luaeval: cannot convert value");
1799     return 0;
1800 }
1801 
1802     static int
1803 luaV_setref (lua_State *L)
1804 {
1805     int		copyID = lua_tointeger(L, 1);
1806     int		abort = FALSE;
1807     typval_T	tv;
1808 
1809     luaV_getfield(L, LUAVIM_LIST);
1810     luaV_getfield(L, LUAVIM_DICT);
1811     lua_pushnil(L);
1812     /* traverse cache table */
1813     while (!abort && lua_next(L, lua_upvalueindex(1)) != 0)
1814     {
1815 	lua_getmetatable(L, -1);
1816 	if (lua_rawequal(L, -1, 2)) /* list? */
1817 	{
1818 	    tv.v_type = VAR_LIST;
1819 	    tv.vval.v_list = (list_T *) lua_touserdata(L, 4); /* key */
1820 	    abort = set_ref_in_item(&tv, copyID, NULL, NULL);
1821 	}
1822 	else if (lua_rawequal(L, -1, 3)) /* dict? */
1823 	{
1824 	    tv.v_type = VAR_DICT;
1825 	    tv.vval.v_dict = (dict_T *) lua_touserdata(L, 4); /* key */
1826 	    abort = set_ref_in_item(&tv, copyID, NULL, NULL);
1827 	}
1828 	lua_pop(L, 2); /* metatable and value */
1829     }
1830     lua_pushinteger(L, abort);
1831     return 1;
1832 }
1833 
1834     static int
1835 luaopen_vim(lua_State *L)
1836 {
1837     /* set cache table */
1838     lua_newtable(L);
1839     lua_newtable(L);
1840     lua_pushstring(L, "v");
1841     lua_setfield(L, -2, "__mode");
1842     lua_setmetatable(L, -2); /* cache is weak-valued */
1843     /* print */
1844     lua_pushcfunction(L, luaV_print);
1845     lua_setglobal(L, "print");
1846     /* debug.debug */
1847     lua_getglobal(L, "debug");
1848     lua_pushcfunction(L, luaV_debug);
1849     lua_setfield(L, -2, "debug");
1850     lua_pop(L, 1);
1851     /* free */
1852     lua_pushlightuserdata(L, (void *) LUAVIM_FREE);
1853     lua_pushvalue(L, 1); /* cache table */
1854     lua_pushcclosure(L, luaV_free, 1);
1855     lua_rawset(L, LUA_REGISTRYINDEX);
1856     /* luaeval */
1857     lua_pushlightuserdata(L, (void *) LUAVIM_LUAEVAL);
1858     lua_pushvalue(L, 1); /* cache table */
1859     lua_pushcclosure(L, luaV_luaeval, 1);
1860     lua_rawset(L, LUA_REGISTRYINDEX);
1861     /* setref */
1862     lua_pushlightuserdata(L, (void *) LUAVIM_SETREF);
1863     lua_pushvalue(L, 1); /* cache table */
1864     lua_pushcclosure(L, luaV_setref, 1);
1865     lua_rawset(L, LUA_REGISTRYINDEX);
1866     /* register */
1867     luaV_newmetatable(L, LUAVIM_LIST);
1868     lua_pushvalue(L, 1);
1869     luaV_openlib(L, luaV_List_mt, 1);
1870     luaV_newmetatable(L, LUAVIM_DICT);
1871     lua_pushvalue(L, 1);
1872     luaV_openlib(L, luaV_Dict_mt, 1);
1873     luaV_newmetatable(L, LUAVIM_FUNCREF);
1874     lua_pushvalue(L, 1);
1875     luaV_openlib(L, luaV_Funcref_mt, 1);
1876     luaV_newmetatable(L, LUAVIM_BUFFER);
1877     lua_pushvalue(L, 1); /* cache table */
1878     luaV_openlib(L, luaV_Buffer_mt, 1);
1879     luaV_newmetatable(L, LUAVIM_WINDOW);
1880     lua_pushvalue(L, 1); /* cache table */
1881     luaV_openlib(L, luaV_Window_mt, 1);
1882     lua_newtable(L); /* vim table */
1883     lua_pushvalue(L, 1); /* cache table */
1884     luaV_openlib(L, luaV_module, 1);
1885     lua_setglobal(L, LUAVIM_NAME);
1886     return 0;
1887 }
1888 
1889     static lua_State *
1890 luaV_newstate(void)
1891 {
1892     lua_State *L = luaL_newstate();
1893     luaL_openlibs(L); /* core libs */
1894     lua_pushcfunction(L, luaopen_vim); /* vim */
1895     lua_call(L, 0, 0);
1896     return L;
1897 }
1898 
1899     static void
1900 luaV_setrange(lua_State *L, int line1, int line2)
1901 {
1902     lua_getglobal(L, LUAVIM_NAME);
1903     lua_pushinteger(L, line1);
1904     lua_setfield(L, -2, "firstline");
1905     lua_pushinteger(L, line2);
1906     lua_setfield(L, -2, "lastline");
1907     lua_pop(L, 1); /* vim table */
1908 }
1909 
1910 
1911 /* =======   Interface   ======= */
1912 
1913 static lua_State *L = NULL;
1914 
1915     static int
1916 lua_isopen(void)
1917 {
1918     return L != NULL;
1919 }
1920 
1921     static int
1922 lua_init(void)
1923 {
1924     if (!lua_isopen())
1925     {
1926 #ifdef DYNAMIC_LUA
1927 	if (!lua_enabled(TRUE))
1928 	{
1929 	    emsg(_("Lua library cannot be loaded."));
1930 	    return FAIL;
1931 	}
1932 #endif
1933 	L = luaV_newstate();
1934     }
1935     return OK;
1936 }
1937 
1938     void
1939 lua_end(void)
1940 {
1941     if (lua_isopen())
1942     {
1943 	lua_close(L);
1944 	L = NULL;
1945 #ifdef DYNAMIC_LUA
1946 	end_dynamic_lua();
1947 #endif
1948     }
1949 }
1950 
1951 /* ex commands */
1952     void
1953 ex_lua(exarg_T *eap)
1954 {
1955     char *script;
1956     if (lua_init() == FAIL) return;
1957     script = (char *) script_get(eap, eap->arg);
1958     if (!eap->skip)
1959     {
1960 	char *s = (script) ? script :  (char *) eap->arg;
1961 	luaV_setrange(L, eap->line1, eap->line2);
1962 	if (luaL_loadbuffer(L, s, strlen(s), LUAVIM_CHUNKNAME)
1963 		|| lua_pcall(L, 0, 0, 0))
1964 	    luaV_emsg(L);
1965     }
1966     if (script != NULL) vim_free(script);
1967 }
1968 
1969     void
1970 ex_luado(exarg_T *eap)
1971 {
1972     linenr_T l;
1973     const char *s = (const char *) eap->arg;
1974     luaL_Buffer b;
1975     size_t len;
1976     buf_T *was_curbuf = curbuf;
1977 
1978     if (lua_init() == FAIL) return;
1979     if (u_save(eap->line1 - 1, eap->line2 + 1) == FAIL)
1980     {
1981 	emsg(_("cannot save undo information"));
1982 	return;
1983     }
1984     luaV_setrange(L, eap->line1, eap->line2);
1985     luaL_buffinit(L, &b);
1986     luaL_addlstring(&b, "return function(line, linenr) ", 30); /* header */
1987     luaL_addlstring(&b, s, strlen(s));
1988     luaL_addlstring(&b, " end", 4); /* footer */
1989     luaL_pushresult(&b);
1990     s = lua_tolstring(L, -1, &len);
1991     if (luaL_loadbuffer(L, s, len, LUAVIM_CHUNKNAME))
1992     {
1993 	luaV_emsg(L);
1994 	lua_pop(L, 1); /* function body */
1995 	return;
1996     }
1997     lua_call(L, 0, 1);
1998     lua_replace(L, -2); /* function -> body */
1999     for (l = eap->line1; l <= eap->line2; l++)
2000     {
2001 	/* Check the line number, the command my have deleted lines. */
2002 	if (l > curbuf->b_ml.ml_line_count)
2003 	    break;
2004 
2005 	lua_pushvalue(L, -1); /* function */
2006 	luaV_pushline(L, curbuf, l); /* current line as arg */
2007 	lua_pushinteger(L, l); /* current line number as arg */
2008 	if (lua_pcall(L, 2, 1, 0))
2009 	{
2010 	    luaV_emsg(L);
2011 	    break;
2012 	}
2013 	/* Catch the command switching to another buffer. */
2014 	if (curbuf != was_curbuf)
2015 	    break;
2016 	if (lua_isstring(L, -1)) /* update line? */
2017 	{
2018 #ifdef HAVE_SANDBOX
2019 	    luaV_checksandbox(L);
2020 #endif
2021 	    ml_replace(l, luaV_toline(L, -1), TRUE);
2022 	    changed_bytes(l, 0);
2023 	    lua_pop(L, 1); /* result from luaV_toline */
2024 	}
2025 	lua_pop(L, 1); /* line */
2026     }
2027     lua_pop(L, 1); /* function */
2028     check_cursor();
2029     update_screen(NOT_VALID);
2030 }
2031 
2032     void
2033 ex_luafile(exarg_T *eap)
2034 {
2035     if (lua_init() == FAIL)
2036 	return;
2037     if (!eap->skip)
2038     {
2039 	luaV_setrange(L, eap->line1, eap->line2);
2040 	if (luaL_loadfile(L, (char *) eap->arg) || lua_pcall(L, 0, 0, 0))
2041 	    luaV_emsg(L);
2042     }
2043 }
2044 
2045 #define luaV_freetype(typ,tname) \
2046 	void \
2047     lua_##tname##_free(typ *o) \
2048     { \
2049 	if (!lua_isopen()) return; \
2050 	luaV_getfield(L, LUAVIM_FREE); \
2051 	lua_pushlightuserdata(L, (void *) o); \
2052 	lua_call(L, 1, 0); \
2053     }
2054 
2055 luaV_freetype(buf_T, buffer)
2056 luaV_freetype(win_T, window)
2057 
2058     void
2059 do_luaeval (char_u *str, typval_T *arg, typval_T *rettv)
2060 {
2061     lua_init();
2062     luaV_getfield(L, LUAVIM_LUAEVAL);
2063     lua_pushstring(L, (char *) str);
2064     lua_pushlightuserdata(L, (void *) arg);
2065     lua_pushlightuserdata(L, (void *) rettv);
2066     lua_call(L, 3, 0);
2067 }
2068 
2069     int
2070 set_ref_in_lua (int copyID)
2071 {
2072     int aborted = 0;
2073 
2074     if (lua_isopen())
2075     {
2076 	luaV_getfield(L, LUAVIM_SETREF);
2077 	/* call the function with 1 arg, getting 1 result back */
2078 	lua_pushinteger(L, copyID);
2079 	lua_call(L, 1, 1);
2080 	/* get the result */
2081 	aborted = lua_tointeger(L, -1);
2082 	/* pop result off the stack */
2083 	lua_pop(L, 1);
2084     }
2085     return aborted;
2086 }
2087 
2088 #endif
2089