[grub2.git] / debian / grub-extras / lua / ldblib.c

/*
** $Id: ldblib.c,v 1.104.1.3 2008/01/21 13:11:21 roberto Exp $
** Interface from Lua to its debug API
** See Copyright Notice in lua.h
*/

#if 0
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#endif

#define ldblib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"


static int db_getregistry (lua_State *L) {
  lua_pushvalue(L, LUA_REGISTRYINDEX);
  return 1;
}


static int db_getmetatable (lua_State *L) {
  luaL_checkany(L, 1);
  if (!lua_getmetatable(L, 1)) {
    lua_pushnil(L);  /* no metatable */
  }
  return 1;
}


static int db_setmetatable (lua_State *L) {
  int t = lua_type(L, 2);
  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
                    "nil or table expected");
  lua_settop(L, 2);
  lua_pushboolean(L, lua_setmetatable(L, 1));
  return 1;
}


static int db_getfenv (lua_State *L) {
  lua_getfenv(L, 1);
  return 1;
}


static int db_setfenv (lua_State *L) {
  luaL_checktype(L, 2, LUA_TTABLE);
  lua_settop(L, 2);
  if (lua_setfenv(L, 1) == 0)
    luaL_error(L, LUA_QL("setfenv")
                  " cannot change environment of given object");
  return 1;
}


static void settabss (lua_State *L, const char *i, const char *v) {
  lua_pushstring(L, v);
  lua_setfield(L, -2, i);
}


static void settabsi (lua_State *L, const char *i, int v) {
  lua_pushinteger(L, v);
  lua_setfield(L, -2, i);
}


static lua_State *getthread (lua_State *L, int *arg) {
  if (lua_isthread(L, 1)) {
    *arg = 1;
    return lua_tothread(L, 1);
  }
  else {
    *arg = 0;
    return L;
  }
}


static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
  if (L == L1) {
    lua_pushvalue(L, -2);
    lua_remove(L, -3);
  }
  else
    lua_xmove(L1, L, 1);
  lua_setfield(L, -2, fname);
}


static int db_getinfo (lua_State *L) {
  lua_Debug ar;
  int arg;
  lua_State *L1 = getthread(L, &arg);
  const char *options = luaL_optstring(L, arg+2, "flnSu");
  if (lua_isnumber(L, arg+1)) {
    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
      lua_pushnil(L);  /* level out of range */
      return 1;
    }
  }
  else if (lua_isfunction(L, arg+1)) {
    lua_pushfstring(L, ">%s", options);
    options = lua_tostring(L, -1);
    lua_pushvalue(L, arg+1);
    lua_xmove(L, L1, 1);
  }
  else
    return luaL_argerror(L, arg+1, "function or level expected");
  if (!lua_getinfo(L1, options, &ar))
    return luaL_argerror(L, arg+2, "invalid option");
  lua_createtable(L, 0, 2);
  if (strchr(options, 'S')) {
    settabss(L, "source", ar.source);
    settabss(L, "short_src", ar.short_src);
    settabsi(L, "linedefined", ar.linedefined);
    settabsi(L, "lastlinedefined", ar.lastlinedefined);
    settabss(L, "what", ar.what);
  }
  if (strchr(options, 'l'))
    settabsi(L, "currentline", ar.currentline);
  if (strchr(options, 'u'))
    settabsi(L, "nups", ar.nups);
  if (strchr(options, 'n')) {
    settabss(L, "name", ar.name);
    settabss(L, "namewhat", ar.namewhat);
  }
  if (strchr(options, 'L'))
    treatstackoption(L, L1, "activelines");
  if (strchr(options, 'f'))
    treatstackoption(L, L1, "func");
  return 1;  /* return table */
}


static int db_getlocal (lua_State *L) {
  int arg;
  lua_State *L1 = getthread(L, &arg);
  lua_Debug ar;
  const char *name;
  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
    return luaL_argerror(L, arg+1, "level out of range");
  name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
  if (name) {
    lua_xmove(L1, L, 1);
    lua_pushstring(L, name);
    lua_pushvalue(L, -2);
    return 2;
  }
  else {
    lua_pushnil(L);
    return 1;
  }
}


static int db_setlocal (lua_State *L) {
  int arg;
  lua_State *L1 = getthread(L, &arg);
  lua_Debug ar;
  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
    return luaL_argerror(L, arg+1, "level out of range");
  luaL_checkany(L, arg+3);
  lua_settop(L, arg+3);
  lua_xmove(L, L1, 1);
  lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
  return 1;
}


static int auxupvalue (lua_State *L, int get) {
  const char *name;
  int n = luaL_checkint(L, 2);
  luaL_checktype(L, 1, LUA_TFUNCTION);
  if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
  if (name == NULL) return 0;
  lua_pushstring(L, name);
  lua_insert(L, -(get+1));
  return get + 1;
}


static int db_getupvalue (lua_State *L) {
  return auxupvalue(L, 1);
}


static int db_setupvalue (lua_State *L) {
  luaL_checkany(L, 3);
  return auxupvalue(L, 0);
}


static const char KEY_HOOK = 'h';


static void hookf (lua_State *L, lua_Debug *ar) {
  static const char *const hooknames[] =
    {"call", "return", "line", "count", "tail return"};
  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
  lua_rawget(L, LUA_REGISTRYINDEX);
  lua_pushlightuserdata(L, L);
  lua_rawget(L, -2);
  if (lua_isfunction(L, -1)) {
    lua_pushstring(L, hooknames[(int)ar->event]);
    if (ar->currentline >= 0)
      lua_pushinteger(L, ar->currentline);
    else lua_pushnil(L);
    lua_assert(lua_getinfo(L, "lS", ar));
    lua_call(L, 2, 0);
  }
}


static int makemask (const char *smask, int count) {
  int mask = 0;
  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
  if (count > 0) mask |= LUA_MASKCOUNT;
  return mask;
}


static char *unmakemask (int mask, char *smask) {
  int i = 0;
  if (mask & LUA_MASKCALL) smask[i++] = 'c';
  if (mask & LUA_MASKRET) smask[i++] = 'r';
  if (mask & LUA_MASKLINE) smask[i++] = 'l';
  smask[i] = '\0';
  return smask;
}


static void gethooktable (lua_State *L) {
  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
  lua_rawget(L, LUA_REGISTRYINDEX);
  if (!lua_istable(L, -1)) {
    lua_pop(L, 1);
    lua_createtable(L, 0, 1);
    lua_pushlightuserdata(L, (void *)&KEY_HOOK);
    lua_pushvalue(L, -2);
    lua_rawset(L, LUA_REGISTRYINDEX);
  }
}


static int db_sethook (lua_State *L) {
  int arg, mask, count;
  lua_Hook func;
  lua_State *L1 = getthread(L, &arg);
  if (lua_isnoneornil(L, arg+1)) {
    lua_settop(L, arg+1);
    func = NULL; mask = 0; count = 0;  /* turn off hooks */
  }
  else {
    const char *smask = luaL_checkstring(L, arg+2);
    luaL_checktype(L, arg+1, LUA_TFUNCTION);
    count = luaL_optint(L, arg+3, 0);
    func = hookf; mask = makemask(smask, count);
  }
  gethooktable(L);
  lua_pushlightuserdata(L, L1);
  lua_pushvalue(L, arg+1);
  lua_rawset(L, -3);  /* set new hook */
  lua_pop(L, 1);  /* remove hook table */
  lua_sethook(L1, func, mask, count);  /* set hooks */
  return 0;
}


static int db_gethook (lua_State *L) {
  int arg;
  lua_State *L1 = getthread(L, &arg);
  char buff[5];
  int mask = lua_gethookmask(L1);
  lua_Hook hook = lua_gethook(L1);
  if (hook != NULL && hook != hookf)  /* external hook? */
    lua_pushliteral(L, "external hook");
  else {
    gethooktable(L);
    lua_pushlightuserdata(L, L1);
    lua_rawget(L, -2);   /* get hook */
    lua_remove(L, -2);  /* remove hook table */
  }
  lua_pushstring(L, unmakemask(mask, buff));
  lua_pushinteger(L, lua_gethookcount(L1));
  return 3;
}


static int db_debug (lua_State *L) {
  for (;;) {
    char buffer[250];
    fputs("lua_debug> ", stderr);
    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
        strcmp(buffer, "cont\n") == 0)
      return 0;
    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
        lua_pcall(L, 0, 0, 0)) {
      fputs(lua_tostring(L, -1), stderr);
      fputs("\n", stderr);
    }
    lua_settop(L, 0);  /* remove eventual returns */
  }
}


#define LEVELS1	12	/* size of the first part of the stack */
#define LEVELS2	10	/* size of the second part of the stack */

static int db_errorfb (lua_State *L) {
  int level;
  int firstpart = 1;  /* still before eventual `...' */
  int arg;
  lua_State *L1 = getthread(L, &arg);
  lua_Debug ar;
  if (lua_isnumber(L, arg+2)) {
    level = (int)lua_tointeger(L, arg+2);
    lua_pop(L, 1);
  }
  else
    level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
  if (lua_gettop(L) == arg)
    lua_pushliteral(L, "");
  else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
  else lua_pushliteral(L, "\n");
  lua_pushliteral(L, "stack traceback:");
  while (lua_getstack(L1, level++, &ar)) {
    if (level > LEVELS1 && firstpart) {
      /* no more than `LEVELS2' more levels? */
      if (!lua_getstack(L1, level+LEVELS2, &ar))
        level--;  /* keep going */
      else {
        lua_pushliteral(L, "\n\t...");  /* too many levels */
        while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
          level++;
      }
      firstpart = 0;
      continue;
    }
    lua_pushliteral(L, "\n\t");
    lua_getinfo(L1, "Snl", &ar);
    lua_pushfstring(L, "%s:", ar.short_src);
    if (ar.currentline > 0)
      lua_pushfstring(L, "%d:", ar.currentline);
    if (*ar.namewhat != '\0')  /* is there a name? */
        lua_pushfstring(L, " in function " LUA_QS, ar.name);
    else {
      if (*ar.what == 'm')  /* main? */
        lua_pushfstring(L, " in main chunk");
      else if (*ar.what == 'C' || *ar.what == 't')
        lua_pushliteral(L, " ?");  /* C function or tail call */
      else
        lua_pushfstring(L, " in function <%s:%d>",
                           ar.short_src, ar.linedefined);
    }
    lua_concat(L, lua_gettop(L) - arg);
  }
  lua_concat(L, lua_gettop(L) - arg);
  return 1;
}


static const luaL_Reg dblib[] = {
  {"debug", db_debug},
  {"getfenv", db_getfenv},
  {"gethook", db_gethook},
  {"getinfo", db_getinfo},
  {"getlocal", db_getlocal},
  {"getregistry", db_getregistry},
  {"getmetatable", db_getmetatable},
  {"getupvalue", db_getupvalue},
  {"setfenv", db_setfenv},
  {"sethook", db_sethook},
  {"setlocal", db_setlocal},
  {"setmetatable", db_setmetatable},
  {"setupvalue", db_setupvalue},
  {"traceback", db_errorfb},
  {NULL, NULL}
};


LUALIB_API int luaopen_debug (lua_State *L) {
  luaL_register(L, LUA_DBLIBNAME, dblib);
  return 1;
}
Commit	Line	Data
90cb9220	1	/*
	2	** $Id: ldblib.c,v 1.104.1.3 2008/01/21 13:11:21 roberto Exp $
	3	** Interface from Lua to its debug API
	4	** See Copyright Notice in lua.h
	5	*/
	6
	7	#if 0
	8	#include <stdio.h>
	9	#include <stdlib.h>
	10	#include <string.h>
	11	#endif
	12
	13	#define ldblib_c
	14	#define LUA_LIB
	15
	16	#include "lua.h"
	17
	18	#include "lauxlib.h"
	19	#include "lualib.h"
	20
	21
	22
	23	static int db_getregistry (lua_State *L) {
	24	lua_pushvalue(L, LUA_REGISTRYINDEX);
	25	return 1;
	26	}
	27
	28
	29	static int db_getmetatable (lua_State *L) {
	30	luaL_checkany(L, 1);
	31	if (!lua_getmetatable(L, 1)) {
	32	lua_pushnil(L); /* no metatable */
	33	}
	34	return 1;
	35	}
	36
	37
	38	static int db_setmetatable (lua_State *L) {
	39	int t = lua_type(L, 2);
	40	luaL_argcheck(L, t == LUA_TNIL \|\| t == LUA_TTABLE, 2,
	41	"nil or table expected");
	42	lua_settop(L, 2);
	43	lua_pushboolean(L, lua_setmetatable(L, 1));
	44	return 1;
	45	}
	46
	47
	48	static int db_getfenv (lua_State *L) {
	49	lua_getfenv(L, 1);
	50	return 1;
	51	}
	52
	53
	54	static int db_setfenv (lua_State *L) {
	55	luaL_checktype(L, 2, LUA_TTABLE);
	56	lua_settop(L, 2);
	57	if (lua_setfenv(L, 1) == 0)
	58	luaL_error(L, LUA_QL("setfenv")
	59	" cannot change environment of given object");
	60	return 1;
	61	}
	62
	63
	64	static void settabss (lua_State L, const char i, const char *v) {
65	lua_pushstring(L, v);
66	lua_setfield(L, -2, i);
67	}
68
69
70	static void settabsi (lua_State L, const char i, int v) {
71	lua_pushinteger(L, v);
72	lua_setfield(L, -2, i);
73	}
74
75
76	static lua_State getthread (lua_State L, int *arg) {
77	if (lua_isthread(L, 1)) {
78	*arg = 1;
79	return lua_tothread(L, 1);
80	}
81	else {
82	*arg = 0;
83	return L;
84	}
85	}
86
87
88	static void treatstackoption (lua_State L, lua_State L1, const char *fname) {
89	if (L == L1) {
90	lua_pushvalue(L, -2);
91	lua_remove(L, -3);
92	}
93	else
94	lua_xmove(L1, L, 1);
95	lua_setfield(L, -2, fname);
96	}
97
98
99	static int db_getinfo (lua_State *L) {
100	lua_Debug ar;
101	int arg;
102	lua_State *L1 = getthread(L, &arg);
103	const char *options = luaL_optstring(L, arg+2, "flnSu");
104	if (lua_isnumber(L, arg+1)) {
105	if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
106	lua_pushnil(L); /* level out of range */
107	return 1;
108	}
109	}
110	else if (lua_isfunction(L, arg+1)) {
111	lua_pushfstring(L, ">%s", options);
112	options = lua_tostring(L, -1);
113	lua_pushvalue(L, arg+1);
114	lua_xmove(L, L1, 1);
115	}
116	else
117	return luaL_argerror(L, arg+1, "function or level expected");
118	if (!lua_getinfo(L1, options, &ar))
119	return luaL_argerror(L, arg+2, "invalid option");
120	lua_createtable(L, 0, 2);
121	if (strchr(options, 'S')) {
122	settabss(L, "source", ar.source);
123	settabss(L, "short_src", ar.short_src);
124	settabsi(L, "linedefined", ar.linedefined);
125	settabsi(L, "lastlinedefined", ar.lastlinedefined);
126	settabss(L, "what", ar.what);
127	}
128	if (strchr(options, 'l'))
129	settabsi(L, "currentline", ar.currentline);
130	if (strchr(options, 'u'))
131	settabsi(L, "nups", ar.nups);
132	if (strchr(options, 'n')) {
133	settabss(L, "name", ar.name);
134	settabss(L, "namewhat", ar.namewhat);
135	}
136	if (strchr(options, 'L'))
137	treatstackoption(L, L1, "activelines");
138	if (strchr(options, 'f'))
139	treatstackoption(L, L1, "func");
140	return 1; /* return table */
141	}
142
143
144	static int db_getlocal (lua_State *L) {
145	int arg;
146	lua_State *L1 = getthread(L, &arg);
147	lua_Debug ar;
148	const char *name;
149	if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar)) /* out of range? */
150	return luaL_argerror(L, arg+1, "level out of range");
151	name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
152	if (name) {
153	lua_xmove(L1, L, 1);
154	lua_pushstring(L, name);
155	lua_pushvalue(L, -2);
156	return 2;
157	}
158	else {
159	lua_pushnil(L);
160	return 1;
161	}
162	}
163
164
165	static int db_setlocal (lua_State *L) {
166	int arg;
167	lua_State *L1 = getthread(L, &arg);
168	lua_Debug ar;
169	if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar)) /* out of range? */
170	return luaL_argerror(L, arg+1, "level out of range");
171	luaL_checkany(L, arg+3);
172	lua_settop(L, arg+3);
173	lua_xmove(L, L1, 1);
174	lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
175	return 1;
176	}
177
178
179	static int auxupvalue (lua_State *L, int get) {
180	const char *name;
181	int n = luaL_checkint(L, 2);
182	luaL_checktype(L, 1, LUA_TFUNCTION);
183	if (lua_iscfunction(L, 1)) return 0; /* cannot touch C upvalues from Lua */
184	name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
185	if (name == NULL) return 0;
186	lua_pushstring(L, name);
187	lua_insert(L, -(get+1));
188	return get + 1;
189	}
190
191
192	static int db_getupvalue (lua_State *L) {
193	return auxupvalue(L, 1);
194	}
195
196
197	static int db_setupvalue (lua_State *L) {
198	luaL_checkany(L, 3);
199	return auxupvalue(L, 0);
200	}
201
202
203
204	static const char KEY_HOOK = 'h';
205
206
207	static void hookf (lua_State L, lua_Debug ar) {
208	static const char *const hooknames[] =
209	{"call", "return", "line", "count", "tail return"};
210	lua_pushlightuserdata(L, (void *)&KEY_HOOK);
211	lua_rawget(L, LUA_REGISTRYINDEX);
212	lua_pushlightuserdata(L, L);
213	lua_rawget(L, -2);
214	if (lua_isfunction(L, -1)) {
215	lua_pushstring(L, hooknames[(int)ar->event]);
216	if (ar->currentline >= 0)
217	lua_pushinteger(L, ar->currentline);
218	else lua_pushnil(L);
219	lua_assert(lua_getinfo(L, "lS", ar));
220	lua_call(L, 2, 0);
221	}
222	}
223
224
225	static int makemask (const char *smask, int count) {
226	int mask = 0;
227	if (strchr(smask, 'c')) mask \|= LUA_MASKCALL;
228	if (strchr(smask, 'r')) mask \|= LUA_MASKRET;
229	if (strchr(smask, 'l')) mask \|= LUA_MASKLINE;
230	if (count > 0) mask \|= LUA_MASKCOUNT;
231	return mask;
232	}
233
234
235	static char unmakemask (int mask, char smask) {
236	int i = 0;
237	if (mask & LUA_MASKCALL) smask[i++] = 'c';
238	if (mask & LUA_MASKRET) smask[i++] = 'r';
239	if (mask & LUA_MASKLINE) smask[i++] = 'l';
240	smask[i] = '\0';
241	return smask;
242	}
243
244
245	static void gethooktable (lua_State *L) {
246	lua_pushlightuserdata(L, (void *)&KEY_HOOK);
247	lua_rawget(L, LUA_REGISTRYINDEX);
248	if (!lua_istable(L, -1)) {
249	lua_pop(L, 1);
250	lua_createtable(L, 0, 1);
251	lua_pushlightuserdata(L, (void *)&KEY_HOOK);
252	lua_pushvalue(L, -2);
253	lua_rawset(L, LUA_REGISTRYINDEX);
254	}
255	}
256
257
258	static int db_sethook (lua_State *L) {
259	int arg, mask, count;
260	lua_Hook func;
261	lua_State *L1 = getthread(L, &arg);
262	if (lua_isnoneornil(L, arg+1)) {
263	lua_settop(L, arg+1);
264	func = NULL; mask = 0; count = 0; /* turn off hooks */
265	}
266	else {
267	const char *smask = luaL_checkstring(L, arg+2);
268	luaL_checktype(L, arg+1, LUA_TFUNCTION);
269	count = luaL_optint(L, arg+3, 0);
270	func = hookf; mask = makemask(smask, count);
271	}
272	gethooktable(L);
273	lua_pushlightuserdata(L, L1);
274	lua_pushvalue(L, arg+1);
275	lua_rawset(L, -3); /* set new hook */
276	lua_pop(L, 1); /* remove hook table */
277	lua_sethook(L1, func, mask, count); /* set hooks */
278	return 0;
279	}
280
281
282	static int db_gethook (lua_State *L) {
283	int arg;
284	lua_State *L1 = getthread(L, &arg);
285	char buff[5];
286	int mask = lua_gethookmask(L1);
287	lua_Hook hook = lua_gethook(L1);
288	if (hook != NULL && hook != hookf) /* external hook? */
289	lua_pushliteral(L, "external hook");
290	else {
291	gethooktable(L);
292	lua_pushlightuserdata(L, L1);
293	lua_rawget(L, -2); /* get hook */
294	lua_remove(L, -2); /* remove hook table */
295	}
296	lua_pushstring(L, unmakemask(mask, buff));
297	lua_pushinteger(L, lua_gethookcount(L1));
298	return 3;
299	}
300
301
302	static int db_debug (lua_State *L) {
303	for (;;) {
304	char buffer[250];
305	fputs("lua_debug> ", stderr);
306	if (fgets(buffer, sizeof(buffer), stdin) == 0 \|\|
307	strcmp(buffer, "cont\n") == 0)
308	return 0;
309	if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") \|\|
310	lua_pcall(L, 0, 0, 0)) {
311	fputs(lua_tostring(L, -1), stderr);
312	fputs("\n", stderr);
313	}
314	lua_settop(L, 0); /* remove eventual returns */
315	}
316	}
317
318
319	#define LEVELS1 12 /* size of the first part of the stack */
320	#define LEVELS2 10 /* size of the second part of the stack */
321
322	static int db_errorfb (lua_State *L) {
323	int level;
324	int firstpart = 1; /* still before eventual `...' */
325	int arg;
326	lua_State *L1 = getthread(L, &arg);
327	lua_Debug ar;
328	if (lua_isnumber(L, arg+2)) {
329	level = (int)lua_tointeger(L, arg+2);
330	lua_pop(L, 1);
331	}
332	else
333	level = (L == L1) ? 1 : 0; /* level 0 may be this own function */
334	if (lua_gettop(L) == arg)
335	lua_pushliteral(L, "");
336	else if (!lua_isstring(L, arg+1)) return 1; /* message is not a string */
337	else lua_pushliteral(L, "\n");
338	lua_pushliteral(L, "stack traceback:");
339	while (lua_getstack(L1, level++, &ar)) {
340	if (level > LEVELS1 && firstpart) {
341	/* no more than `LEVELS2' more levels? */
342	if (!lua_getstack(L1, level+LEVELS2, &ar))
343	level--; /* keep going */
344	else {
345	lua_pushliteral(L, "\n\t..."); /* too many levels */
346	while (lua_getstack(L1, level+LEVELS2, &ar)) /* find last levels */
347	level++;
348	}
349	firstpart = 0;
350	continue;
351	}
352	lua_pushliteral(L, "\n\t");
353	lua_getinfo(L1, "Snl", &ar);
354	lua_pushfstring(L, "%s:", ar.short_src);
355	if (ar.currentline > 0)
356	lua_pushfstring(L, "%d:", ar.currentline);
357	if (ar.namewhat != '\0') / is there a name? */
358	lua_pushfstring(L, " in function " LUA_QS, ar.name);
359	else {
360	if (ar.what == 'm') / main? */
361	lua_pushfstring(L, " in main chunk");
362	else if (ar.what == 'C' \|\| ar.what == 't')
363	lua_pushliteral(L, " ?"); /* C function or tail call */
364	else
365	lua_pushfstring(L, " in function <%s:%d>",
366	ar.short_src, ar.linedefined);
367	}
368	lua_concat(L, lua_gettop(L) - arg);
369	}
370	lua_concat(L, lua_gettop(L) - arg);
371	return 1;
372	}
373
374
375	static const luaL_Reg dblib[] = {
376	{"debug", db_debug},
377	{"getfenv", db_getfenv},
378	{"gethook", db_gethook},
379	{"getinfo", db_getinfo},
380	{"getlocal", db_getlocal},
381	{"getregistry", db_getregistry},
382	{"getmetatable", db_getmetatable},
383	{"getupvalue", db_getupvalue},
384	{"setfenv", db_setfenv},
385	{"sethook", db_sethook},
386	{"setlocal", db_setlocal},
387	{"setmetatable", db_setmetatable},
388	{"setupvalue", db_setupvalue},
389	{"traceback", db_errorfb},
390	{NULL, NULL}
391	};
392
393
394	LUALIB_API int luaopen_debug (lua_State *L) {
395	luaL_register(L, LUA_DBLIBNAME, dblib);
396	return 1;
397	}
398