/script_binding/lua/lua/ldblib.c

  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