deps/lua/src/lauxlib.c

/*
** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/


#include <ctype.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>


/* This file uses only the official API of Lua.
** Any function declared here could be written as an application function.
*/

#define lauxlib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"


#define FREELIST_REF	0	/* free list of references */


/* convert a stack index to positive */
#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
					lua_gettop(L) + (i) + 1)


/*
** {======================================================
** Error-report functions
** =======================================================
*/


LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
  lua_Debug ar;
  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
    return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
  lua_getinfo(L, "n", &ar);
  if (strcmp(ar.namewhat, "method") == 0) {
    narg--;  /* do not count `self' */
    if (narg == 0)  /* error is in the self argument itself? */
      return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
                           ar.name, extramsg);
  }
  if (ar.name == NULL)
    ar.name = "?";
  return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
                        narg, ar.name, extramsg);
}


LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
  const char *msg = lua_pushfstring(L, "%s expected, got %s",
                                    tname, luaL_typename(L, narg));
  return luaL_argerror(L, narg, msg);
}


static void tag_error (lua_State *L, int narg, int tag) {
  luaL_typerror(L, narg, lua_typename(L, tag));
}


LUALIB_API void luaL_where (lua_State *L, int level) {
  lua_Debug ar;
  if (lua_getstack(L, level, &ar)) {  /* check function at level */
    lua_getinfo(L, "Sl", &ar);  /* get info about it */
    if (ar.currentline > 0) {  /* is there info? */
      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
      return;
    }
  }
  lua_pushliteral(L, "");  /* else, no information available... */
}


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);
  return lua_error(L);
}

/* }====================================================== */


LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
                                 const char *const lst[]) {
  const char *name = (def) ? luaL_optstring(L, narg, def) :
                             luaL_checkstring(L, narg);
  int i;
  for (i=0; lst[i]; i++)
    if (strcmp(lst[i], name) == 0)
      return i;
  return luaL_argerror(L, narg,
                       lua_pushfstring(L, "invalid option " LUA_QS, name));
}


LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
  lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
  if (!lua_isnil(L, -1))  /* name already in use? */
    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 */
  return 1;
}


LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
  void *p = lua_touserdata(L, ud);
  if (p != NULL) {  /* value is a userdata? */
    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
      lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get correct metatable */
      if (lua_rawequal(L, -1, -2)) {  /* does it have the correct mt? */
        lua_pop(L, 2);  /* remove both metatables */
        return p;
      }
    }
  }
  luaL_typerror(L, ud, tname);  /* else error */
  return NULL;  /* to avoid warnings */
}


LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
  if (!lua_checkstack(L, space))
    luaL_error(L, "stack overflow (%s)", mes);
}


LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
  if (lua_type(L, narg) != t)
    tag_error(L, narg, t);
}


LUALIB_API void luaL_checkany (lua_State *L, int narg) {
  if (lua_type(L, narg) == LUA_TNONE)
    luaL_argerror(L, narg, "value expected");
}


LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
  const char *s = lua_tolstring(L, narg, len);
  if (!s) tag_error(L, narg, LUA_TSTRING);
  return s;
}


LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
                                        const char *def, size_t *len) {
  if (lua_isnoneornil(L, narg)) {
    if (len)
      *len = (def ? strlen(def) : 0);
    return def;
  }
  else return luaL_checklstring(L, narg, len);
}


LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
  lua_Number d = lua_tonumber(L, narg);
  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
    tag_error(L, narg, LUA_TNUMBER);
  return d;
}


LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
  return luaL_opt(L, luaL_checknumber, narg, def);
}


LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
  lua_Integer d = lua_tointeger(L, narg);
  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
    tag_error(L, narg, LUA_TNUMBER);
  return d;
}


LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
                                                      lua_Integer def) {
  return luaL_opt(L, luaL_checkinteger, narg, def);
}


LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
  if (!lua_getmetatable(L, obj))  /* no metatable? */
    return 0;
  lua_pushstring(L, event);
  lua_rawget(L, -2);
  if (lua_isnil(L, -1)) {
    lua_pop(L, 2);  /* remove metatable and metafield */
    return 0;
  }
  else {
    lua_remove(L, -2);  /* remove only metatable */
    return 1;
  }
}


LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
  obj = abs_index(L, obj);
  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
    return 0;
  lua_pushvalue(L, obj);
  lua_call(L, 1, 1);
  return 1;
}


LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
                                const luaL_Reg *l) {
  luaI_openlib(L, libname, l, 0);
}


static int libsize (const luaL_Reg *l) {
  int size = 0;
  for (; l->name; l++) size++;
  return size;
}


LUALIB_API void luaI_openlib (lua_State *L, const char *libname,
                              const luaL_Reg *l, int nup) {
  if (libname) {
    int size = libsize(l);
    /* check whether lib already exists */
    luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);
    lua_getfield(L, -1, libname);  /* get _LOADED[libname] */
    if (!lua_istable(L, -1)) {  /* not found? */
      lua_pop(L, 1);  /* remove previous result */
      /* try global variable (and create one if it does not exist) */
      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 */
    }
    lua_remove(L, -2);  /* remove _LOADED table */
    lua_insert(L, -(nup+1));  /* move library table to below upvalues */
  }
  for (; l->name; l++) {
    int i;
    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);
  }
  lua_pop(L, nup);  /* remove upvalues */
}


/*
** {======================================================
** getn-setn: size for arrays
** =======================================================
*/

#if defined(LUA_COMPAT_GETN)

static int checkint (lua_State *L, int topop) {
  int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1;
  lua_pop(L, topop);
  return n;
}


static void getsizes (lua_State *L) {
  lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");
  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 */
  }
}


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);
  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);
  }
  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' */
  }
}


LUALIB_API int luaL_getn (lua_State *L, int t) {
  int n;
  t = abs_index(L, t);
  lua_pushliteral(L, "n");  /* try t.n */
  lua_rawget(L, t);
  if ((n = checkint(L, 1)) >= 0) return n;
  getsizes(L);  /* else try sizes[t] */
  lua_pushvalue(L, t);
  lua_rawget(L, -2);
  if ((n = checkint(L, 2)) >= 0) return n;
  return (int)lua_objlen(L, t);
}

#endif

/* }====================================================== */


LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
                                                               const char *r) {
  const char *wild;
  size_t l = strlen(p);
  luaL_Buffer b;
  luaL_buffinit(L, &b);
  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' */
  }
  luaL_addstring(&b, s);  /* push last suffix */
  luaL_pushresult(&b);
  return lua_tostring(L, -1);
}


LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
                                       const char *fname, int szhint) {
  const char *e;
  lua_pushvalue(L, idx);
  do {
    e = strchr(fname, '.');
    if (e == NULL) e = fname + strlen(fname);
    lua_pushlstring(L, fname, e - fname);
    lua_rawget(L, -2);
    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 */
    }
    else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
      lua_pop(L, 2);  /* remove table and value */
      return fname;  /* return problematic part of the name */
    }
    lua_remove(L, -2);  /* remove previous table */
    fname = e + 1;
  } while (*e == '.');
  return NULL;
}


/*
** {======================================================
** Generic Buffer manipulation
** =======================================================
*/


#define bufflen(B)	((B)->p - (B)->buffer)
#define bufffree(B)	((size_t)(LUAL_BUFFERSIZE - bufflen(B)))

#define LIMIT	(LUA_MINSTACK/2)


static int emptybuffer (luaL_Buffer *B) {
  size_t l = bufflen(B);
  if (l == 0) return 0;  /* put nothing on stack */
  else {
    lua_pushlstring(B->L, B->buffer, l);
    B->p = B->buffer;
    B->lvl++;
    return 1;
  }
}


static void adjuststack (luaL_Buffer *B) {
  if (B->lvl > 1) {
    lua_State *L = B->L;
    int toget = 1;  /* number of levels to concat */
    size_t toplen = lua_strlen(L, -1);
    do {
      size_t l = lua_strlen(L, -(toget+1));
      if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
        toplen += l;
        toget++;
      }
      else break;
    } while (toget < B->lvl);
    lua_concat(L, toget);
    B->lvl = B->lvl - toget + 1;
  }
}


LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
  if (emptybuffer(B))
    adjuststack(B);
  return B->buffer;
}


LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
  while (l--)
    luaL_addchar(B, *s++);
}


LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
  luaL_addlstring(B, s, strlen(s));
}


LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
  emptybuffer(B);
  lua_concat(B->L, B->lvl);
  B->lvl = 1;
}


LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
  lua_State *L = B->L;
  size_t vl;
  const char *s = lua_tolstring(L, -1, &vl);
  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 */
  }
  else {
    if (emptybuffer(B))
      lua_insert(L, -2);  /* put buffer before new value */
    B->lvl++;  /* add new value into B stack */
    adjuststack(B);
  }
}


LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
  B->L = L;
  B->p = B->buffer;
  B->lvl = 0;
}

/* }====================================================== */


LUALIB_API int luaL_ref (lua_State *L, int t) {
  int ref;
  t = abs_index(L, t);
  if (lua_isnil(L, -1)) {
    lua_pop(L, 1);  /* remove from stack */
    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
  }
  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 */
  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]) */
  }
  else {  /* no free elements */
    ref = (int)lua_objlen(L, t);
    ref++;  /* create new reference */
  }
  lua_rawseti(L, t, ref);
  return ref;
}


LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
  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 */
  }
}


/*
** {======================================================
** Load functions
** =======================================================
*/

typedef struct LoadF {
  int extraline;
  FILE *f;
  char buff[LUAL_BUFFERSIZE];
} LoadF;


static const char *getF (lua_State *L, void *ud, size_t *size) {
  LoadF *lf = (LoadF *)ud;
  (void)L;
  if (lf->extraline) {
    lf->extraline = 0;
    *size = 1;
    return "\n";
  }
  if (feof(lf->f)) return NULL;
  *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
  return (*size > 0) ? lf->buff : NULL;
}


static int errfile (lua_State *L, const char *what, int fnameindex) {
  const char *serr = strerror(errno);
  const char *filename = lua_tostring(L, fnameindex) + 1;
  lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
  lua_remove(L, fnameindex);
  return LUA_ERRFILE;
}


LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
  LoadF lf;
  int status, readstatus;
  int c;
  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
  lf.extraline = 0;
  if (filename == NULL) {
    lua_pushliteral(L, "=stdin");
    lf.f = stdin;
  }
  else {
    lua_pushfstring(L, "@%s", filename);
    lf.f = fopen(filename, "r");
    if (lf.f == NULL) return errfile(L, "open", fnameindex);
  }
  c = getc(lf.f);
  if (c == '#') {  /* Unix exec. file? */
    lf.extraline = 1;
    while ((c = getc(lf.f)) != EOF && c != '\n') ;  /* skip first line */
    if (c == '\n') c = getc(lf.f);
  }
  if (c == LUA_SIGNATURE[0] && filename) {  /* binary file? */
    lf.f = freopen(filename, "rb", lf.f);  /* reopen in binary mode */
    if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
    /* skip eventual `#!...' */
   while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ;
    lf.extraline = 0;
  }
  ungetc(c, lf.f);
  status = lua_load(L, getF, &lf, lua_tostring(L, -1));
  readstatus = ferror(lf.f);
  if (filename) fclose(lf.f);  /* close file (even in case of errors) */
  if (readstatus) {
    lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
    return errfile(L, "read", fnameindex);
  }
  lua_remove(L, fnameindex);
  return status;
}


typedef struct LoadS {
  const char *s;
  size_t size;
} LoadS;


static const char *getS (lua_State *L, void *ud, size_t *size) {
  LoadS *ls = (LoadS *)ud;
  (void)L;
  if (ls->size == 0) return NULL;
  *size = ls->size;
  ls->size = 0;
  return ls->s;
}


LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
                                const char *name) {
  LoadS ls;
  ls.s = buff;
  ls.size = size;
  return lua_load(L, getS, &ls, name);
}


LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) {
  return luaL_loadbuffer(L, s, strlen(s), s);
}


/* }====================================================== */


static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
  (void)ud;
  (void)osize;
  if (nsize == 0) {
    free(ptr);
    return NULL;
  }
  else
    return realloc(ptr, nsize);
}


static int panic (lua_State *L) {
  (void)L;  /* to avoid warnings */
  fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n",
                   lua_tostring(L, -1));
  return 0;
}


LUALIB_API lua_State *luaL_newstate (void) {
  lua_State *L = lua_newstate(l_alloc, NULL);
  if (L) lua_atpanic(L, &panic);
  return L;
}
Commit	Line	Data
	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	*/
	6
	7
	8	#include <ctype.h>
	9	#include <errno.h>
	10	#include <stdarg.h>
	11	#include <stdio.h>
	12	#include <stdlib.h>
	13	#include <string.h>
	14
	15
	16	/* This file uses only the official API of Lua.
	17	** Any function declared here could be written as an application function.
	18	*/
	19
	20	#define lauxlib_c
	21	#define LUA_LIB
	22
	23	#include "lua.h"
	24
	25	#include "lauxlib.h"
	26
	27
	28	#define FREELIST_REF 0 /* free list of references */
	29
	30
	31	/* convert a stack index to positive */
	32	#define abs_index(L, i) ((i) > 0 \|\| (i) <= LUA_REGISTRYINDEX ? (i) : \
	33	lua_gettop(L) + (i) + 1)
	34
	35
	36	/*
	37	** {======================================================
	38	** Error-report functions
	39	** =======================================================
	40	*/
	41
	42
	43	LUALIB_API int luaL_argerror (lua_State L, int narg, const char extramsg) {
	44	lua_Debug ar;
	45	if (!lua_getstack(L, 0, &ar)) /* no stack frame? */
	46	return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
	47	lua_getinfo(L, "n", &ar);
	48	if (strcmp(ar.namewhat, "method") == 0) {
	49	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)",
	52	ar.name, extramsg);
	53	}
	54	if (ar.name == NULL)
	55	ar.name = "?";
	56	return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
	57	narg, ar.name, extramsg);
	58	}
	59
	60
	61	LUALIB_API int luaL_typerror (lua_State L, int narg, const char tname) {
	62	const char *msg = lua_pushfstring(L, "%s expected, got %s",
	63	tname, luaL_typename(L, narg));
	64	return luaL_argerror(L, narg, msg);
	65	}
	66
	67
	68	static void tag_error (lua_State *L, int narg, int tag) {
	69	luaL_typerror(L, narg, lua_typename(L, tag));
	70	}
	71
	72
	73	LUALIB_API void luaL_where (lua_State *L, int level) {
	74	lua_Debug ar;
	75	if (lua_getstack(L, level, &ar)) { /* check function at level */
	76	lua_getinfo(L, "Sl", &ar); /* get info about it */
	77	if (ar.currentline > 0) { /* is there info? */
	78	lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
	79	return;
	80	}
	81	}
	82	lua_pushliteral(L, ""); /* else, no information available... */
	83	}
	84
	85
	86	LUALIB_API int luaL_error (lua_State L, const char fmt, ...) {
	87	va_list argp;
	88	va_start(argp, fmt);
	89	luaL_where(L, 1);
	90	lua_pushvfstring(L, fmt, argp);
	91	va_end(argp);
	92	lua_concat(L, 2);
	93	return lua_error(L);
	94	}
	95
	96	/* }====================================================== */
	97
	98
	99	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) :
	102	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,
	108	lua_pushfstring(L, "invalid option " LUA_QS, name));
	109	}
	110
	111
	112	LUALIB_API int luaL_newmetatable (lua_State L, const char tname) {
	113	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 */
	116	lua_pop(L, 1);
	117	lua_newtable(L); /* create metatable */
	118	lua_pushvalue(L, -1);
	119	lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */
	120	return 1;
	121	}
	122
	123
	124	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? */
	128	lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */
	129	if (lua_rawequal(L, -1, -2)) { /* does it have the correct mt? */
	130	lua_pop(L, 2); /* remove both metatables */
	131	return p;
	132	}
	133	}
	134	}
	135	luaL_typerror(L, ud, tname); /* else error */
	136	return NULL; /* to avoid warnings */
	137	}
	138
	139
	140	LUALIB_API void luaL_checkstack (lua_State L, int space, const char mes) {
	141	if (!lua_checkstack(L, space))
	142	luaL_error(L, "stack overflow (%s)", mes);
	143	}
	144
	145
	146	LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
	147	if (lua_type(L, narg) != t)
	148	tag_error(L, narg, t);
	149	}
	150
	151
	152	LUALIB_API void luaL_checkany (lua_State *L, int narg) {
	153	if (lua_type(L, narg) == LUA_TNONE)
	154	luaL_argerror(L, narg, "value expected");
	155	}
	156
	157
	158	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	}
	163
	164
	165	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	}
	174
	175
	176	LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
	177	lua_Number d = lua_tonumber(L, narg);
	178	if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */
	179	tag_error(L, narg, LUA_TNUMBER);
	180	return d;
	181	}
	182
	183
	184	LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
	185	return luaL_opt(L, luaL_checknumber, narg, def);
	186	}
	187
	188
	189	LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
	190	lua_Integer d = lua_tointeger(L, narg);
	191	if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */
	192	tag_error(L, narg, LUA_TNUMBER);
	193	return d;
	194	}
	195
	196
	197	LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
	198	lua_Integer def) {
	199	return luaL_opt(L, luaL_checkinteger, narg, def);
	200	}
	201
	202
	203	LUALIB_API int luaL_getmetafield (lua_State L, int obj, const char event) {
	204	if (!lua_getmetatable(L, obj)) /* no metatable? */
	205	return 0;
	206	lua_pushstring(L, event);
	207	lua_rawget(L, -2);
	208	if (lua_isnil(L, -1)) {
	209	lua_pop(L, 2); /* remove metatable and metafield */
	210	return 0;
	211	}
	212	else {
	213	lua_remove(L, -2); /* remove only metatable */
	214	return 1;
	215	}
	216	}
	217
	218
	219	LUALIB_API int luaL_callmeta (lua_State L, int obj, const char event) {
	220	obj = abs_index(L, obj);
	221	if (!luaL_getmetafield(L, obj, event)) /* no metafield? */
	222	return 0;
	223	lua_pushvalue(L, obj);
	224	lua_call(L, 1, 1);
	225	return 1;
	226	}
	227
	228
	229	LUALIB_API void (luaL_register) (lua_State L, const char libname,
	230	const luaL_Reg *l) {
	231	luaI_openlib(L, libname, l, 0);
	232	}
	233
	234
	235	static int libsize (const luaL_Reg *l) {
	236	int size = 0;
	237	for (; l->name; l++) size++;
	238	return size;
	239	}
	240
	241
	242	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 */
	247	luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);
	248	lua_getfield(L, -1, libname); /* get _LOADED[libname] */
	249	if (!lua_istable(L, -1)) { /* not found? */
	250	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)
	253	luaL_error(L, "name conflict for module " LUA_QS, libname);
	254	lua_pushvalue(L, -1);
	255	lua_setfield(L, -3, libname); /* _LOADED[libname] = new table */
	256	}
	257	lua_remove(L, -2); /* remove _LOADED table */
	258	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 */
	263	lua_pushvalue(L, -nup);
	264	lua_pushcclosure(L, l->func, nup);
	265	lua_setfield(L, -(nup+2), l->name);
	266	}
	267	lua_pop(L, nup); /* remove upvalues */
	268	}
	269
	270
	271
	272	/*
	273	** {======================================================
	274	** getn-setn: size for arrays
	275	** =======================================================
	276	*/
	277
	278	#if defined(LUA_COMPAT_GETN)
	279
	280	static int checkint (lua_State *L, int topop) {
	281	int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1;
	282	lua_pop(L, topop);
	283	return n;
	284	}
	285
	286
	287	static void getsizes (lua_State *L) {
	288	lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");
	289	if (lua_isnil(L, -1)) { /* no `size' table? */
	290	lua_pop(L, 1); /* remove nil */
	291	lua_newtable(L); /* create it */
	292	lua_pushvalue(L, -1); /* `size' will be its own metatable */
	293	lua_setmetatable(L, -2);
	294	lua_pushliteral(L, "kv");
	295	lua_setfield(L, -2, "__mode"); /* metatable(N).__mode = "kv" */
	296	lua_pushvalue(L, -1);
	297	lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES"); /* store in register */
	298	}
	299	}
	300
	301
	302	LUALIB_API void luaL_setn (lua_State *L, int t, int n) {
	303	t = abs_index(L, t);
	304	lua_pushliteral(L, "n");
	305	lua_rawget(L, t);
	306	if (checkint(L, 1) >= 0) { /* is there a numeric field `n'? */
	307	lua_pushliteral(L, "n"); /* use it */
	308	lua_pushinteger(L, n);
	309	lua_rawset(L, t);
	310	}
	311	else { /* use `sizes' */
	312	getsizes(L);
	313	lua_pushvalue(L, t);
	314	lua_pushinteger(L, n);
	315	lua_rawset(L, -3); /* sizes[t] = n */
	316	lua_pop(L, 1); /* remove `sizes' */
	317	}
	318	}
	319
	320
	321	LUALIB_API int luaL_getn (lua_State *L, int t) {
	322	int n;
	323	t = abs_index(L, t);
	324	lua_pushliteral(L, "n"); /* try t.n */
	325	lua_rawget(L, t);
	326	if ((n = checkint(L, 1)) >= 0) return n;
	327	getsizes(L); /* else try sizes[t] */
	328	lua_pushvalue(L, t);
	329	lua_rawget(L, -2);
	330	if ((n = checkint(L, 2)) >= 0) return n;
	331	return (int)lua_objlen(L, t);
	332	}
	333
	334	#endif
	335
	336	/* }====================================================== */
	337
	338
	339
	340	LUALIB_API const char luaL_gsub (lua_State L, const char s, const char p,
	341	const char *r) {
	342	const char *wild;
	343	size_t l = strlen(p);
	344	luaL_Buffer b;
	345	luaL_buffinit(L, &b);
	346	while ((wild = strstr(s, p)) != NULL) {
	347	luaL_addlstring(&b, s, wild - s); /* push prefix */
	348	luaL_addstring(&b, r); /* push replacement in place of pattern */
	349	s = wild + l; /* continue after `p' */
	350	}
	351	luaL_addstring(&b, s); /* push last suffix */
	352	luaL_pushresult(&b);
	353	return lua_tostring(L, -1);
	354	}
	355
	356
	357	LUALIB_API const char luaL_findtable (lua_State L, int idx,
	358	const char *fname, int szhint) {
	359	const char *e;
	360	lua_pushvalue(L, idx);
	361	do {
	362	e = strchr(fname, '.');
	363	if (e == NULL) e = fname + strlen(fname);
	364	lua_pushlstring(L, fname, e - fname);
	365	lua_rawget(L, -2);
	366	if (lua_isnil(L, -1)) { /* no such field? */
	367	lua_pop(L, 1); /* remove this nil */
	368	lua_createtable(L, 0, (e == '.' ? 1 : szhint)); / new table for field */
	369	lua_pushlstring(L, fname, e - fname);
	370	lua_pushvalue(L, -2);
	371	lua_settable(L, -4); /* set new table into field */
	372	}
	373	else if (!lua_istable(L, -1)) { /* field has a non-table value? */
	374	lua_pop(L, 2); /* remove table and value */
	375	return fname; /* return problematic part of the name */
	376	}
	377	lua_remove(L, -2); /* remove previous table */
	378	fname = e + 1;
	379	} while (*e == '.');
	380	return NULL;
	381	}
	382
	383
	384
	385	/*
	386	** {======================================================
	387	** Generic Buffer manipulation
	388	** =======================================================
	389	*/
	390
	391
	392	#define bufflen(B) ((B)->p - (B)->buffer)
	393	#define bufffree(B) ((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
	394
	395	#define LIMIT (LUA_MINSTACK/2)
	396
	397
	398	static int emptybuffer (luaL_Buffer *B) {
	399	size_t l = bufflen(B);
	400	if (l == 0) return 0; /* put nothing on stack */
	401	else {
	402	lua_pushlstring(B->L, B->buffer, l);
	403	B->p = B->buffer;
	404	B->lvl++;
	405	return 1;
	406	}
	407	}
	408
	409
	410	static void adjuststack (luaL_Buffer *B) {
	411	if (B->lvl > 1) {
	412	lua_State *L = B->L;
	413	int toget = 1; /* number of levels to concat */
	414	size_t toplen = lua_strlen(L, -1);
	415	do {
	416	size_t l = lua_strlen(L, -(toget+1));
	417	if (B->lvl - toget + 1 >= LIMIT \|\| toplen > l) {
	418	toplen += l;
	419	toget++;
	420	}
	421	else break;
	422	} while (toget < B->lvl);
	423	lua_concat(L, toget);
	424	B->lvl = B->lvl - toget + 1;
	425	}
	426	}
	427
	428
	429	LUALIB_API char luaL_prepbuffer (luaL_Buffer B) {
	430	if (emptybuffer(B))
	431	adjuststack(B);
	432	return B->buffer;
	433	}
	434
	435
	436	LUALIB_API void luaL_addlstring (luaL_Buffer B, const char s, size_t l) {
	437	while (l--)
	438	luaL_addchar(B, *s++);
	439	}
	440
	441
	442	LUALIB_API void luaL_addstring (luaL_Buffer B, const char s) {
	443	luaL_addlstring(B, s, strlen(s));
	444	}
	445
	446
	447	LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
	448	emptybuffer(B);
	449	lua_concat(B->L, B->lvl);
	450	B->lvl = 1;
	451	}
	452
	453
	454	LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
	455	lua_State *L = B->L;
	456	size_t vl;
	457	const char *s = lua_tolstring(L, -1, &vl);
	458	if (vl <= bufffree(B)) { /* fit into buffer? */
	459	memcpy(B->p, s, vl); /* put it there */
	460	B->p += vl;
	461	lua_pop(L, 1); /* remove from stack */
	462	}
	463	else {
	464	if (emptybuffer(B))
	465	lua_insert(L, -2); /* put buffer before new value */
	466	B->lvl++; /* add new value into B stack */
	467	adjuststack(B);
	468	}
	469	}
	470
	471
	472	LUALIB_API void luaL_buffinit (lua_State L, luaL_Buffer B) {
	473	B->L = L;
	474	B->p = B->buffer;
	475	B->lvl = 0;
	476	}
	477
	478	/* }====================================================== */
	479
	480
	481	LUALIB_API int luaL_ref (lua_State *L, int t) {
	482	int ref;
	483	t = abs_index(L, t);
	484	if (lua_isnil(L, -1)) {
	485	lua_pop(L, 1); /* remove from stack */
	486	return LUA_REFNIL; /* `nil' has a unique fixed reference */
	487	}
	488	lua_rawgeti(L, t, FREELIST_REF); /* get first free element */
	489	ref = (int)lua_tointeger(L, -1); /* ref = t[FREELIST_REF] */
	490	lua_pop(L, 1); /* remove it from stack */
	491	if (ref != 0) { /* any free element? */
	492	lua_rawgeti(L, t, ref); /* remove it from list */
	493	lua_rawseti(L, t, FREELIST_REF); /* (t[FREELIST_REF] = t[ref]) */
	494	}
	495	else { /* no free elements */
	496	ref = (int)lua_objlen(L, t);
	497	ref++; /* create new reference */
	498	}
	499	lua_rawseti(L, t, ref);
	500	return ref;
	501	}
	502
	503
	504	LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
	505	if (ref >= 0) {
	506	t = abs_index(L, t);
	507	lua_rawgeti(L, t, FREELIST_REF);
	508	lua_rawseti(L, t, ref); /* t[ref] = t[FREELIST_REF] */
	509	lua_pushinteger(L, ref);
	510	lua_rawseti(L, t, FREELIST_REF); /* t[FREELIST_REF] = ref */
	511	}
	512	}
	513
	514
	515
	516	/*
	517	** {======================================================
	518	** Load functions
	519	** =======================================================
	520	*/
	521
	522	typedef struct LoadF {
	523	int extraline;
	524	FILE *f;
	525	char buff[LUAL_BUFFERSIZE];
	526	} LoadF;
	527
	528
	529	static const char getF (lua_State L, void ud, size_t size) {
	530	LoadF lf = (LoadF )ud;
	531	(void)L;
	532	if (lf->extraline) {
	533	lf->extraline = 0;
	534	*size = 1;
	535	return "\n";
	536	}
	537	if (feof(lf->f)) return NULL;
	538	*size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
	539	return (*size > 0) ? lf->buff : NULL;
	540	}
	541
	542
	543	static int errfile (lua_State L, const char what, int fnameindex) {
	544	const char *serr = strerror(errno);
	545	const char *filename = lua_tostring(L, fnameindex) + 1;
	546	lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
	547	lua_remove(L, fnameindex);
	548	return LUA_ERRFILE;
	549	}
	550
	551
	552	LUALIB_API int luaL_loadfile (lua_State L, const char filename) {
	553	LoadF lf;
	554	int status, readstatus;
	555	int c;
	556	int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */
	557	lf.extraline = 0;
	558	if (filename == NULL) {
	559	lua_pushliteral(L, "=stdin");
	560	lf.f = stdin;
	561	}
	562	else {
	563	lua_pushfstring(L, "@%s", filename);
	564	lf.f = fopen(filename, "r");
	565	if (lf.f == NULL) return errfile(L, "open", fnameindex);
	566	}
	567	c = getc(lf.f);
	568	if (c == '#') { /* Unix exec. file? */
	569	lf.extraline = 1;
	570	while ((c = getc(lf.f)) != EOF && c != '\n') ; /* skip first line */
	571	if (c == '\n') c = getc(lf.f);
	572	}
	573	if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */
	574	lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */
	575	if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
	576	/* skip eventual `#!...' */
	577	while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ;
	578	lf.extraline = 0;
	579	}
	580	ungetc(c, lf.f);
	581	status = lua_load(L, getF, &lf, lua_tostring(L, -1));
	582	readstatus = ferror(lf.f);
	583	if (filename) fclose(lf.f); /* close file (even in case of errors) */
	584	if (readstatus) {
	585	lua_settop(L, fnameindex); /* ignore results from `lua_load' */
	586	return errfile(L, "read", fnameindex);
	587	}
	588	lua_remove(L, fnameindex);
	589	return status;
	590	}
	591
	592
	593	typedef struct LoadS {
	594	const char *s;
	595	size_t size;
	596	} LoadS;
	597
	598
	599	static const char getS (lua_State L, void ud, size_t size) {
	600	LoadS ls = (LoadS )ud;
	601	(void)L;
	602	if (ls->size == 0) return NULL;
	603	*size = ls->size;
	604	ls->size = 0;
	605	return ls->s;
	606	}
	607
	608
	609	LUALIB_API int luaL_loadbuffer (lua_State L, const char buff, size_t size,
	610	const char *name) {
	611	LoadS ls;
	612	ls.s = buff;
	613	ls.size = size;
	614	return lua_load(L, getS, &ls, name);
	615	}
	616
	617
	618	LUALIB_API int (luaL_loadstring) (lua_State L, const char s) {
	619	return luaL_loadbuffer(L, s, strlen(s), s);
	620	}
	621
	622
	623
	624	/* }====================================================== */
	625
	626
	627	static void l_alloc (void ud, void *ptr, size_t osize, size_t nsize) {
	628	(void)ud;
	629	(void)osize;
	630	if (nsize == 0) {
	631	free(ptr);
	632	return NULL;
	633	}
	634	else
	635	return realloc(ptr, nsize);
	636	}
	637
	638
	639	static int panic (lua_State *L) {
	640	(void)L; /* to avoid warnings */
	641	fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n",
	642	lua_tostring(L, -1));
	643	return 0;
	644	}
	645
	646
	647	LUALIB_API lua_State *luaL_newstate (void) {
	648	lua_State *L = lua_newstate(l_alloc, NULL);
	649	if (L) lua_atpanic(L, &panic);
	650	return L;
	651	}
	652