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