1 /*
2 ** $Id: ldblib.c,v 1.132.1.2 2015/02/19 17:16:55 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 #define HOOKKEY "_HKEY"
22
23
checkstack(lua_State * L,lua_State * L1,int n)24 static void checkstack (lua_State *L, lua_State *L1, int n) {
25 if (L != L1 && !lua_checkstack(L1, n))
26 luaL_error(L, "stack overflow");
27 }
28
29
db_getregistry(lua_State * L)30 static int db_getregistry (lua_State *L) {
31 lua_pushvalue(L, LUA_REGISTRYINDEX);
32 return 1;
33 }
34
35
db_getmetatable(lua_State * L)36 static int db_getmetatable (lua_State *L) {
37 luaL_checkany(L, 1);
38 if (!lua_getmetatable(L, 1)) {
39 lua_pushnil(L); /* no metatable */
40 }
41 return 1;
42 }
43
44
db_setmetatable(lua_State * L)45 static int db_setmetatable (lua_State *L) {
46 int t = lua_type(L, 2);
47 luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
48 "nil or table expected");
49 lua_settop(L, 2);
50 lua_setmetatable(L, 1);
51 return 1; /* return 1st argument */
52 }
53
54
db_getuservalue(lua_State * L)55 static int db_getuservalue (lua_State *L) {
56 if (lua_type(L, 1) != LUA_TUSERDATA)
57 lua_pushnil(L);
58 else
59 lua_getuservalue(L, 1);
60 return 1;
61 }
62
63
db_setuservalue(lua_State * L)64 static int db_setuservalue (lua_State *L) {
65 if (lua_type(L, 1) == LUA_TLIGHTUSERDATA)
66 luaL_argerror(L, 1, "full userdata expected, got light userdata");
67 luaL_checktype(L, 1, LUA_TUSERDATA);
68 if (!lua_isnoneornil(L, 2))
69 luaL_checktype(L, 2, LUA_TTABLE);
70 lua_settop(L, 2);
71 lua_setuservalue(L, 1);
72 return 1;
73 }
74
75
settabss(lua_State * L,const char * i,const char * v)76 static void settabss (lua_State *L, const char *i, const char *v) {
77 lua_pushstring(L, v);
78 lua_setfield(L, -2, i);
79 }
80
81
settabsi(lua_State * L,const char * i,int v)82 static void settabsi (lua_State *L, const char *i, int v) {
83 lua_pushinteger(L, v);
84 lua_setfield(L, -2, i);
85 }
86
87
settabsb(lua_State * L,const char * i,int v)88 static void settabsb (lua_State *L, const char *i, int v) {
89 lua_pushboolean(L, v);
90 lua_setfield(L, -2, i);
91 }
92
93
getthread(lua_State * L,int * arg)94 static lua_State *getthread (lua_State *L, int *arg) {
95 if (lua_isthread(L, 1)) {
96 *arg = 1;
97 return lua_tothread(L, 1);
98 }
99 else {
100 *arg = 0;
101 return L;
102 }
103 }
104
105
treatstackoption(lua_State * L,lua_State * L1,const char * fname)106 static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
107 if (L == L1) {
108 lua_pushvalue(L, -2);
109 lua_remove(L, -3);
110 }
111 else
112 lua_xmove(L1, L, 1);
113 lua_setfield(L, -2, fname);
114 }
115
116
db_getinfo(lua_State * L)117 static int db_getinfo (lua_State *L) {
118 lua_Debug ar;
119 int arg;
120 lua_State *L1 = getthread(L, &arg);
121 const char *options = luaL_optstring(L, arg+2, "flnStu");
122 checkstack(L, L1, 3);
123 if (lua_isnumber(L, arg+1)) {
124 if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
125 lua_pushnil(L); /* level out of range */
126 return 1;
127 }
128 }
129 else if (lua_isfunction(L, arg+1)) {
130 lua_pushfstring(L, ">%s", options);
131 options = lua_tostring(L, -1);
132 lua_pushvalue(L, arg+1);
133 lua_xmove(L, L1, 1);
134 }
135 else
136 return luaL_argerror(L, arg+1, "function or level expected");
137 if (!lua_getinfo(L1, options, &ar))
138 return luaL_argerror(L, arg+2, "invalid option");
139 lua_createtable(L, 0, 2);
140 if (strchr(options, 'S')) {
141 settabss(L, "source", ar.source);
142 settabss(L, "short_src", ar.short_src);
143 settabsi(L, "linedefined", ar.linedefined);
144 settabsi(L, "lastlinedefined", ar.lastlinedefined);
145 settabss(L, "what", ar.what);
146 }
147 if (strchr(options, 'l'))
148 settabsi(L, "currentline", ar.currentline);
149 if (strchr(options, 'u')) {
150 settabsi(L, "nups", ar.nups);
151 settabsi(L, "nparams", ar.nparams);
152 settabsb(L, "isvararg", ar.isvararg);
153 }
154 if (strchr(options, 'n')) {
155 settabss(L, "name", ar.name);
156 settabss(L, "namewhat", ar.namewhat);
157 }
158 if (strchr(options, 't'))
159 settabsb(L, "istailcall", ar.istailcall);
160 if (strchr(options, 'L'))
161 treatstackoption(L, L1, "activelines");
162 if (strchr(options, 'f'))
163 treatstackoption(L, L1, "func");
164 return 1; /* return table */
165 }
166
167
db_getlocal(lua_State * L)168 static int db_getlocal (lua_State *L) {
169 int arg;
170 lua_State *L1 = getthread(L, &arg);
171 lua_Debug ar;
172 const char *name;
173 int nvar = luaL_checkint(L, arg+2); /* local-variable index */
174 if (lua_isfunction(L, arg + 1)) { /* function argument? */
175 lua_pushvalue(L, arg + 1); /* push function */
176 lua_pushstring(L, lua_getlocal(L, NULL, nvar)); /* push local name */
177 return 1;
178 }
179 else { /* stack-level argument */
180 if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar)) /* out of range? */
181 return luaL_argerror(L, arg+1, "level out of range");
182 checkstack(L, L1, 1);
183 name = lua_getlocal(L1, &ar, nvar);
184 if (name) {
185 lua_xmove(L1, L, 1); /* push local value */
186 lua_pushstring(L, name); /* push name */
187 lua_pushvalue(L, -2); /* re-order */
188 return 2;
189 }
190 else {
191 lua_pushnil(L); /* no name (nor value) */
192 return 1;
193 }
194 }
195 }
196
197
db_setlocal(lua_State * L)198 static int db_setlocal (lua_State *L) {
199 int arg;
200 lua_State *L1 = getthread(L, &arg);
201 lua_Debug ar;
202 if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar)) /* out of range? */
203 return luaL_argerror(L, arg+1, "level out of range");
204 luaL_checkany(L, arg+3);
205 lua_settop(L, arg+3);
206 checkstack(L, L1, 1);
207 lua_xmove(L, L1, 1);
208 lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
209 return 1;
210 }
211
212
auxupvalue(lua_State * L,int get)213 static int auxupvalue (lua_State *L, int get) {
214 const char *name;
215 int n = luaL_checkint(L, 2);
216 luaL_checktype(L, 1, LUA_TFUNCTION);
217 name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
218 if (name == NULL) return 0;
219 lua_pushstring(L, name);
220 lua_insert(L, -(get+1));
221 return get + 1;
222 }
223
224
db_getupvalue(lua_State * L)225 static int db_getupvalue (lua_State *L) {
226 return auxupvalue(L, 1);
227 }
228
229
db_setupvalue(lua_State * L)230 static int db_setupvalue (lua_State *L) {
231 luaL_checkany(L, 3);
232 return auxupvalue(L, 0);
233 }
234
235
checkupval(lua_State * L,int argf,int argnup)236 static int checkupval (lua_State *L, int argf, int argnup) {
237 lua_Debug ar;
238 int nup = luaL_checkint(L, argnup);
239 luaL_checktype(L, argf, LUA_TFUNCTION);
240 lua_pushvalue(L, argf);
241 lua_getinfo(L, ">u", &ar);
242 luaL_argcheck(L, 1 <= nup && nup <= ar.nups, argnup, "invalid upvalue index");
243 return nup;
244 }
245
246
db_upvalueid(lua_State * L)247 static int db_upvalueid (lua_State *L) {
248 int n = checkupval(L, 1, 2);
249 lua_pushlightuserdata(L, lua_upvalueid(L, 1, n));
250 return 1;
251 }
252
253
db_upvaluejoin(lua_State * L)254 static int db_upvaluejoin (lua_State *L) {
255 int n1 = checkupval(L, 1, 2);
256 int n2 = checkupval(L, 3, 4);
257 luaL_argcheck(L, !lua_iscfunction(L, 1), 1, "Lua function expected");
258 luaL_argcheck(L, !lua_iscfunction(L, 3), 3, "Lua function expected");
259 lua_upvaluejoin(L, 1, n1, 3, n2);
260 return 0;
261 }
262
263
264 #define gethooktable(L) luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY)
265
266
hookf(lua_State * L,lua_Debug * ar)267 static void hookf (lua_State *L, lua_Debug *ar) {
268 static const char *const hooknames[] =
269 {"call", "return", "line", "count", "tail call"};
270 gethooktable(L);
271 lua_pushthread(L);
272 lua_rawget(L, -2);
273 if (lua_isfunction(L, -1)) {
274 lua_pushstring(L, hooknames[(int)ar->event]);
275 if (ar->currentline >= 0)
276 lua_pushinteger(L, ar->currentline);
277 else lua_pushnil(L);
278 lua_assert(lua_getinfo(L, "lS", ar));
279 lua_call(L, 2, 0);
280 }
281 }
282
283
makemask(const char * smask,int count)284 static int makemask (const char *smask, int count) {
285 int mask = 0;
286 if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
287 if (strchr(smask, 'r')) mask |= LUA_MASKRET;
288 if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
289 if (count > 0) mask |= LUA_MASKCOUNT;
290 return mask;
291 }
292
293
unmakemask(int mask,char * smask)294 static char *unmakemask (int mask, char *smask) {
295 int i = 0;
296 if (mask & LUA_MASKCALL) smask[i++] = 'c';
297 if (mask & LUA_MASKRET) smask[i++] = 'r';
298 if (mask & LUA_MASKLINE) smask[i++] = 'l';
299 smask[i] = '\0';
300 return smask;
301 }
302
303
db_sethook(lua_State * L)304 static int db_sethook (lua_State *L) {
305 int arg, mask, count;
306 lua_Hook func;
307 lua_State *L1 = getthread(L, &arg);
308 if (lua_isnoneornil(L, arg+1)) {
309 lua_settop(L, arg+1);
310 func = NULL; mask = 0; count = 0; /* turn off hooks */
311 }
312 else {
313 const char *smask = luaL_checkstring(L, arg+2);
314 luaL_checktype(L, arg+1, LUA_TFUNCTION);
315 count = luaL_optint(L, arg+3, 0);
316 func = hookf; mask = makemask(smask, count);
317 }
318 if (gethooktable(L) == 0) { /* creating hook table? */
319 lua_pushstring(L, "k");
320 lua_setfield(L, -2, "__mode"); /** hooktable.__mode = "k" */
321 lua_pushvalue(L, -1);
322 lua_setmetatable(L, -2); /* setmetatable(hooktable) = hooktable */
323 }
324 checkstack(L, L1, 1);
325 lua_pushthread(L1); lua_xmove(L1, L, 1);
326 lua_pushvalue(L, arg+1);
327 lua_rawset(L, -3); /* set new hook */
328 lua_sethook(L1, func, mask, count); /* set hooks */
329 return 0;
330 }
331
332
db_gethook(lua_State * L)333 static int db_gethook (lua_State *L) {
334 int arg;
335 lua_State *L1 = getthread(L, &arg);
336 char buff[5];
337 int mask = lua_gethookmask(L1);
338 lua_Hook hook = lua_gethook(L1);
339 if (hook != NULL && hook != hookf) /* external hook? */
340 lua_pushliteral(L, "external hook");
341 else {
342 gethooktable(L);
343 checkstack(L, L1, 1);
344 lua_pushthread(L1); lua_xmove(L1, L, 1);
345 lua_rawget(L, -2); /* get hook */
346 lua_remove(L, -2); /* remove hook table */
347 }
348 lua_pushstring(L, unmakemask(mask, buff));
349 lua_pushinteger(L, lua_gethookcount(L1));
350 return 3;
351 }
352
353
db_debug(lua_State * L)354 static int db_debug (lua_State *L) {
355 for (;;) {
356 char buffer[250];
357 luai_writestringerror("%s", "lua_debug> ");
358 if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
359 strcmp(buffer, "cont\n") == 0)
360 return 0;
361 if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
362 lua_pcall(L, 0, 0, 0))
363 luai_writestringerror("%s\n", lua_tostring(L, -1));
364 lua_settop(L, 0); /* remove eventual returns */
365 }
366 }
367
368
db_traceback(lua_State * L)369 static int db_traceback (lua_State *L) {
370 int arg;
371 lua_State *L1 = getthread(L, &arg);
372 const char *msg = lua_tostring(L, arg + 1);
373 if (msg == NULL && !lua_isnoneornil(L, arg + 1)) /* non-string 'msg'? */
374 lua_pushvalue(L, arg + 1); /* return it untouched */
375 else {
376 int level = luaL_optint(L, arg + 2, (L == L1) ? 1 : 0);
377 luaL_traceback(L, L1, msg, level);
378 }
379 return 1;
380 }
381
382
383 static const luaL_Reg dblib[] = {
384 {"debug", db_debug},
385 {"getuservalue", db_getuservalue},
386 {"gethook", db_gethook},
387 {"getinfo", db_getinfo},
388 {"getlocal", db_getlocal},
389 {"getregistry", db_getregistry},
390 {"getmetatable", db_getmetatable},
391 {"getupvalue", db_getupvalue},
392 {"upvaluejoin", db_upvaluejoin},
393 {"upvalueid", db_upvalueid},
394 {"setuservalue", db_setuservalue},
395 {"sethook", db_sethook},
396 {"setlocal", db_setlocal},
397 {"setmetatable", db_setmetatable},
398 {"setupvalue", db_setupvalue},
399 {"traceback", db_traceback},
400 {NULL, NULL}
401 };
402
403
luaopen_debug(lua_State * L)404 LUAMOD_API int luaopen_debug (lua_State *L) {
405 luaL_newlib(L, dblib);
406 return 1;
407 }
408
409