root/lib/lua/lauxlib.c

DEFINITIONS

1. luaL_argerror
2. luaL_typerror
3. tag_error
4. luaL_where
5. luaL_error
6. luaL_checkoption
7. luaL_newmetatable
8. luaL_checkudata
9. luaL_checkstack
10. luaL_checktype
11. luaL_checkany
12. luaL_checklstring
13. luaL_optlstring
14. luaL_checknumber
15. luaL_optnumber
16. luaL_checkinteger
17. luaL_optinteger
18. luaL_getmetafield
19. luaL_callmeta
20. libsize
21. luaI_openlib
22. checkint
23. getsizes
24. luaL_setn
25. luaL_getn
26. luaL_gsub
27. luaL_findtable
28. emptybuffer
29. adjuststack
30. luaL_prepbuffer
31. luaL_addlstring
32. luaL_addstring
33. luaL_pushresult
34. luaL_addvalue
35. luaL_buffinit
36. luaL_ref
37. luaL_unref
38. getF
39. getF
40. errfile
41. luaL_loadfile
42. luaL_loadfile
43. getS
44. luaL_loadbuffer
45. l_alloc
46. panic
47. luaL_newstate

   1 /*
   2 ** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $
   3 ** Auxiliary functions for building Lua libraries
   4 ** See Copyright Notice in lua.h
   5 */
   8 #include <ctype.h>
   9 #include <errno.h>
  10 #include <stdarg.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  16 /* This file uses only the official API of Lua.
  17 ** Any function declared here could be written as an application function.
  18 */
  20 #define lauxlib_c
  21 #define LUA_LIB
  23 #include "lua.h"
  25 #include "lauxlib.h"
  28 #define FREELIST_REF    0       /* free list of references */
  31 /* convert a stack index to positive */
  32 #define abs_index(L, i)         ((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
lua_gettop(L) + (i) + 1)
  36 /*
  37 ** {======================================================
  38 ** Error-report functions
  39 ** =======================================================
  40 */
LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
lua_Debug ar;
  45   if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
  46     return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
lua_getinfo(L, "n", &ar);
  48   if (strcmp(ar.namewhat, "method") == 0) {
narg--;  /* do not count `self' */
  50     if (narg == 0)  /* error is in the self argument itself? */
  51       return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
ar.name, extramsg);
  53   }
  54   if (ar.name == NULL)
ar.name = "?";
  56   return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
narg, ar.name, extramsg);
  58 }
LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
  62   const char *msg = lua_pushfstring(L, "%s expected, got %s",
tname, luaL_typename(L, narg));
  64   return luaL_argerror(L, narg, msg);
  65 }
  68 static void tag_error (lua_State *L, int narg, int tag) {
luaL_typerror(L, narg, lua_typename(L, tag));
  70 }
LUALIB_API void luaL_where (lua_State *L, int level) {
lua_Debug ar;
  75   if (lua_getstack(L, level, &ar)) {  /* check function at level */
lua_getinfo(L, "Sl", &ar);  /* get info about it */
  77     if (ar.currentline > 0) {  /* is there info? */
lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
  79       return;
  80     }
  81   }
lua_pushliteral(L, "");  /* else, no information available... */
  83 }
LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
va_list argp;
va_start(argp, fmt);
luaL_where(L, 1);
lua_pushvfstring(L, fmt, argp);
va_end(argp);
lua_concat(L, 2);
  93   return lua_error(L);
  94 }
  96 /* }====================================================== */
LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
 100                                  const char *const lst[]) {
 101   const char *name = (def) ? luaL_optstring(L, narg, def) :
luaL_checkstring(L, narg);
 103   int i;
 104   for (i=0; lst[i]; i++)
 105     if (strcmp(lst[i], name) == 0)
 106       return i;
 107   return luaL_argerror(L, narg,
lua_pushfstring(L, "invalid option " LUA_QS, name));
 109 }
LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
 114   if (!lua_isnil(L, -1))  /* name already in use? */
 115     return 0;  /* leave previous value on top, but return 0 */
lua_pop(L, 1);
lua_newtable(L);  /* create metatable */
lua_pushvalue(L, -1);
lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
 120   return 1;
 121 }
LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
 125   void *p = lua_touserdata(L, ud);
 126   if (p != NULL) {  /* value is a userdata? */
 127     if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get correct metatable */
 129       if (lua_rawequal(L, -1, -2)) {  /* does it have the correct mt? */
lua_pop(L, 2);  /* remove both metatables */
 131         return p;
 132       }
 133     }
 134   }
luaL_typerror(L, ud, tname);  /* else error */
 136   return NULL;  /* to avoid warnings */
 137 }
LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
 141   if (!lua_checkstack(L, space))
luaL_error(L, "stack overflow (%s)", mes);
 143 }
LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
 147   if (lua_type(L, narg) != t)
tag_error(L, narg, t);
 149 }
LUALIB_API void luaL_checkany (lua_State *L, int narg) {
 153   if (lua_type(L, narg) == LUA_TNONE)
luaL_argerror(L, narg, "value expected");
 155 }
LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
 159   const char *s = lua_tolstring(L, narg, len);
 160   if (!s) tag_error(L, narg, LUA_TSTRING);
 161   return s;
 162 }
LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
 166                                         const char *def, size_t *len) {
 167   if (lua_isnoneornil(L, narg)) {
 168     if (len)
 169       *len = (def ? strlen(def) : 0);
 170     return def;
 171   }
 172   else return luaL_checklstring(L, narg, len);
 173 }
LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
lua_Number d = lua_tonumber(L, narg);
 178   if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
tag_error(L, narg, LUA_TNUMBER);
 180   return d;
 181 }
LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
 185   return luaL_opt(L, luaL_checknumber, narg, def);
 186 }
LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
lua_Integer d = lua_tointeger(L, narg);
 191   if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
tag_error(L, narg, LUA_TNUMBER);
 193   return d;
 194 }
LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
lua_Integer def) {
 199   return luaL_opt(L, luaL_checkinteger, narg, def);
 200 }
LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
 204   if (!lua_getmetatable(L, obj))  /* no metatable? */
 205     return 0;
lua_pushstring(L, event);
lua_rawget(L, -2);
 208   if (lua_isnil(L, -1)) {
lua_pop(L, 2);  /* remove metatable and metafield */
 210     return 0;
 211   }
 212   else {
lua_remove(L, -2);  /* remove only metatable */
 214     return 1;
 215   }
 216 }
LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
obj = abs_index(L, obj);
 221   if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
 222     return 0;
lua_pushvalue(L, obj);
lua_call(L, 1, 1);
 225   return 1;
 226 }
LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
 230                                 const luaL_Reg *l) {
luaI_openlib(L, libname, l, 0);
 232 }
 235 static int libsize (const luaL_Reg *l) {
 236   int size = 0;
 237   for (; l->name; l++) size++;
 238   return size;
 239 }
LUALIB_API void luaI_openlib (lua_State *L, const char *libname,
 243                               const luaL_Reg *l, int nup) {
 244   if (libname) {
 245     int size = libsize(l);
 246     /* check whether lib already exists */
luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);
lua_getfield(L, -1, libname);  /* get _LOADED[libname] */
 249     if (!lua_istable(L, -1)) {  /* not found? */
lua_pop(L, 1);  /* remove previous result */
 251       /* try global variable (and create one if it does not exist) */
 252       if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, size) != NULL)
luaL_error(L, "name conflict for module " LUA_QS, libname);
lua_pushvalue(L, -1);
lua_setfield(L, -3, libname);  /* _LOADED[libname] = new table */
 256     }
lua_remove(L, -2);  /* remove _LOADED table */
lua_insert(L, -(nup+1));  /* move library table to below upvalues */
 259   }
 260   for (; l->name; l++) {
 261     int i;
 262     for (i=0; i<nup; i++)  /* copy upvalues to the top */
lua_pushvalue(L, -nup);
lua_pushcclosure(L, l->func, nup);
lua_setfield(L, -(nup+2), l->name);
 266   }
lua_pop(L, nup);  /* remove upvalues */
 268 }
 272 /*
 273 ** {======================================================
 274 ** getn-setn: size for arrays
 275 ** =======================================================
 276 */
 278 #if defined(LUA_COMPAT_GETN)
 280 static int checkint (lua_State *L, int topop) {
 281   int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1;
lua_pop(L, topop);
 283   return n;
 284 }
 287 static void getsizes (lua_State *L) {
lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");
 289   if (lua_isnil(L, -1)) {  /* no `size' table? */
lua_pop(L, 1);  /* remove nil */
lua_newtable(L);  /* create it */
lua_pushvalue(L, -1);  /* `size' will be its own metatable */
lua_setmetatable(L, -2);
lua_pushliteral(L, "kv");
lua_setfield(L, -2, "__mode");  /* metatable(N).__mode = "kv" */
lua_pushvalue(L, -1);
lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");  /* store in register */
 298   }
 299 }
LUALIB_API void luaL_setn (lua_State *L, int t, int n) {
t = abs_index(L, t);
lua_pushliteral(L, "n");
lua_rawget(L, t);
 306   if (checkint(L, 1) >= 0) {  /* is there a numeric field `n'? */
lua_pushliteral(L, "n");  /* use it */
lua_pushinteger(L, n);
lua_rawset(L, t);
 310   }
 311   else {  /* use `sizes' */
getsizes(L);
lua_pushvalue(L, t);
lua_pushinteger(L, n);
lua_rawset(L, -3);  /* sizes[t] = n */
lua_pop(L, 1);  /* remove `sizes' */
 317   }
 318 }
LUALIB_API int luaL_getn (lua_State *L, int t) {
 322   int n;
t = abs_index(L, t);
lua_pushliteral(L, "n");  /* try t.n */
lua_rawget(L, t);
 326   if ((n = checkint(L, 1)) >= 0) return n;
getsizes(L);  /* else try sizes[t] */
lua_pushvalue(L, t);
lua_rawget(L, -2);
 330   if ((n = checkint(L, 2)) >= 0) return n;
 331   return (int)lua_objlen(L, t);
 332 }
 334 #endif
 336 /* }====================================================== */
LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
 340                                                                const char *r) {
 341   const char *wild;
size_t l = strlen(p);
luaL_Buffer b;
luaL_buffinit(L, &b);
 345   while ((wild = strstr(s, p)) != NULL) {
luaL_addlstring(&b, s, wild - s);  /* push prefix */
luaL_addstring(&b, r);  /* push replacement in place of pattern */
s = wild + l;  /* continue after `p' */
 349   }
luaL_addstring(&b, s);  /* push last suffix */
luaL_pushresult(&b);
 352   return lua_tostring(L, -1);
 353 }
LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
 356                                        const char *fname, int szhint) {
 357   const char *e;
lua_pushvalue(L, idx);
 359   do {
e = strchr(fname, '.');
 361     if (e == NULL) e = fname + strlen(fname);
lua_pushlstring(L, fname, e - fname);
lua_rawget(L, -2);
 364     if (lua_isnil(L, -1)) {  /* no such field? */
lua_pop(L, 1);  /* remove this nil */
lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
lua_pushlstring(L, fname, e - fname);
lua_pushvalue(L, -2);
lua_settable(L, -4);  /* set new table into field */
 370     }
 371     else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
lua_pop(L, 2);  /* remove table and value */
 373       return fname;  /* return problematic part of the name */
 374     }
lua_remove(L, -2);  /* remove previous table */
fname = e + 1;
 377   } while (*e == '.');
 378   return NULL;
 379 }
 383 /*
 384 ** {======================================================
 385 ** Generic Buffer manipulation
 386 ** =======================================================
 387 */
 390 #define bufflen(B)      ((B)->p - (B)->buffer)
 391 #define bufffree(B)     ((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
 393 #define LIMIT   (LUA_MINSTACK/2)
 396 static int emptybuffer (luaL_Buffer *B) {
size_t l = bufflen(B);
 398   if (l == 0) return 0;  /* put nothing on stack */
 399   else {
lua_pushlstring(B->L, B->buffer, l);
B->p = B->buffer;
B->lvl++;
 403     return 1;
 404   }
 405 }
 408 static void adjuststack (luaL_Buffer *B) {
 409   if (B->lvl > 1) {
lua_State *L = B->L;
 411     int toget = 1;  /* number of levels to concat */
size_t toplen = lua_strlen(L, -1);
 413     do {
size_t l = lua_strlen(L, -(toget+1));
 415       if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
toplen += l;
toget++;
 418       }
 419       else break;
 420     } while (toget < B->lvl);
lua_concat(L, toget);
B->lvl = B->lvl - toget + 1;
 423   }
 424 }
LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
 428   if (emptybuffer(B))
adjuststack(B);
 430   return B->buffer;
 431 }
LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
 435   while (l--)
luaL_addchar(B, *s++);
 437 }
LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
luaL_addlstring(B, s, strlen(s));
 442 }
LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
emptybuffer(B);
lua_concat(B->L, B->lvl);
B->lvl = 1;
 449 }
LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
lua_State *L = B->L;
size_t vl;
 455   const char *s = lua_tolstring(L, -1, &vl);
 456   if (vl <= bufffree(B)) {  /* fit into buffer? */
memcpy(B->p, s, vl);  /* put it there */
B->p += vl;
lua_pop(L, 1);  /* remove from stack */
 460   }
 461   else {
 462     if (emptybuffer(B))
lua_insert(L, -2);  /* put buffer before new value */
B->lvl++;  /* add new value into B stack */
adjuststack(B);
 466   }
 467 }
LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
B->L = L;
B->p = B->buffer;
B->lvl = 0;
 474 }
 476 /* }====================================================== */
LUALIB_API int luaL_ref (lua_State *L, int t) {
 480   int ref;
t = abs_index(L, t);
 482   if (lua_isnil(L, -1)) {
lua_pop(L, 1);  /* remove from stack */
 484     return LUA_REFNIL;  /* `nil' has a unique fixed reference */
 485   }
lua_rawgeti(L, t, FREELIST_REF);  /* get first free element */
ref = (int)lua_tointeger(L, -1);  /* ref = t[FREELIST_REF] */
lua_pop(L, 1);  /* remove it from stack */
 489   if (ref != 0) {  /* any free element? */
lua_rawgeti(L, t, ref);  /* remove it from list */
lua_rawseti(L, t, FREELIST_REF);  /* (t[FREELIST_REF] = t[ref]) */
 492   }
 493   else {  /* no free elements */
ref = (int)lua_objlen(L, t);
ref++;  /* create new reference */
 496   }
lua_rawseti(L, t, ref);
 498   return ref;
 499 }
LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
 503   if (ref >= 0) {
t = abs_index(L, t);
lua_rawgeti(L, t, FREELIST_REF);
lua_rawseti(L, t, ref);  /* t[ref] = t[FREELIST_REF] */
lua_pushinteger(L, ref);
lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
 509   }
 510 }
 514 /*
 515 ** {======================================================
 516 ** Load functions
 517 ** =======================================================
 518 */
 519 #if 0
 520 typedef struct LoadF {
 521   int extraline;
FILE *f;
 523   char buff[LUAL_BUFFERSIZE];
 524 } LoadF;
 527 static const char *getF (lua_State *L, void *ud, size_t *size) {
LoadF *lf = (LoadF *)ud;
 529   (void)L;
 530   if (lf->extraline) {
lf->extraline = 0;
 532     *size = 1;
 533     return "\n";
 534   }
 535   if (feof(lf->f)) return NULL;
 536   *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
 537   return (*size > 0) ? lf->buff : NULL;
 538 }
 539 #else
 540 typedef struct LoadF {
FILE *f;
 542   char buff[LUAL_BUFFERSIZE];
 543 } LoadF;
 545 static const char *getF (lua_State *L, void *ud, size_t *size) {
LoadF *lf = (LoadF *)ud;
 547   (void)L;
 548   if (feof(lf->f)) return NULL;
 549   *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
 550   return (*size > 0) ? lf->buff : NULL;
 551 }
 552 #endif
 554 static int errfile (lua_State *L, const char *what, int fnameindex) {
 555 #if 0
 556   const char *serr = strerror(errno);
 557   const char *filename = lua_tostring(L, fnameindex) + 1;
lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
 559 #else
 560   const char *filename = lua_tostring(L, fnameindex) + 1;
lua_pushfstring(L, "cannot %s %s", what, filename);
 562 #endif
lua_remove(L, fnameindex);
 564   return LUA_ERRFILE;
 565 }
 567 #if 0
LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
LoadF lf;
 570   int status, readstatus;
 571   int c;
 572   int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
lf.extraline = 0;
 574   if (filename == NULL) {
lua_pushliteral(L, "=stdin");
lf.f = stdin;
 577   }
 578   else {
lua_pushfstring(L, "@%s", filename);
lf.f = fopen(filename, "r");
 581     if (lf.f == NULL) return errfile(L, "open", fnameindex);
 582   }
c = getc(lf.f);
 584   if (c == '#') {  /* Unix exec. file? */
lf.extraline = 1;
 586     while ((c = getc(lf.f)) != EOF && c != '\n') ;  /* skip first line */
 587     if (c == '\n') c = getc(lf.f);
 588   }
 589   if (c == LUA_SIGNATURE[0] && filename) {  /* binary file? */
lf.f = freopen(filename, "rb", lf.f);  /* reopen in binary mode */
 591     if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
 592     /* skip eventual `#!...' */
 593    while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ;
lf.extraline = 0;
 595   }
ungetc(c, lf.f);
status = lua_load(L, getF, &lf, lua_tostring(L, -1));
readstatus = ferror(lf.f);
 599   if (filename) fclose(lf.f);  /* close file (even in case of errors) */
 600   if (readstatus) {
lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
 602     return errfile(L, "read", fnameindex);
 603   }
lua_remove(L, fnameindex);
 605   return status;
 606 }
 607 #else
LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
LoadF lf;
 610   int status, readerror;
 611   char c;
 612   int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
lua_pushfstring(L, "@%s", filename);
lf.f = fopen(filename, "rb"); // cams don't translate crlf anyway
 615   if (lf.f == NULL) return errfile(L, "fopen", fnameindex);
status = lua_load(L, getF, &lf, lua_tostring(L, -1));
readerror = ((fread(&c, 1, 1, lf.f) < 1) && !feof(lf.f));
fclose(lf.f);  /* close file (even in case of errors) */
 621   if (readerror) {
lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
 623     return errfile(L, "read", fnameindex);
 624   }
lua_remove(L, fnameindex);
 626   return status;
 627 }
 628 #endif
 630 typedef struct LoadS {
 631   const char *s;
size_t size;
 633 } LoadS;
 636 static const char *getS (lua_State *L, void *ud, size_t *size) {
LoadS *ls = (LoadS *)ud;
 638   (void)L;
 639   if (ls->size == 0) return NULL;
 640   *size = ls->size;
ls->size = 0;
 642   return ls->s;
 643 }
LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
 647                                 const char *name) {
LoadS ls;
ls.s = buff;
ls.size = size;
 651   return lua_load(L, getS, &ls, name);
 652 }
LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) {
 656   return luaL_loadbuffer(L, s, strlen(s), s);
 657 }
 661 /* }====================================================== */
 664 static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
 665   (void)ud;
 666   (void)osize;
 667   if (nsize == 0) {
free(ptr);
 669     return NULL;
 670   }
 671   else {
 672     if( nsize <= osize ) {
 673       return ptr;
 674     }
 675     void* res = malloc( nsize );
 676     if( !res )
 677       return NULL;
memcpy( res, ptr, osize );
free( ptr );
 680     return res;
 681   }
 682 }
 685 static int panic (lua_State *L) {
 686   (void)L;  /* to avoid warnings */
 687 #if 0
printf( "PANIC: unprotected error in call to Lua API (%s)\n",
lua_tostring(L, -1));
 690 #endif
 691   return 0;
 692 }
LUALIB_API lua_State *luaL_newstate (void) {
lua_State *L = lua_newstate(l_alloc, NULL);
 697   if (L) lua_atpanic(L, &panic);
 698   return L;
 699 }