lua/lapi.c
2000-08-31 11:08:27 -03:00

380 lines
7.7 KiB
C

/*
** $Id: lapi.c,v 1.90 2000/08/29 20:43:28 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
#include <string.h>
#include "lua.h"
#include "lapi.h"
#include "lauxlib.h"
#include "ldo.h"
#include "lfunc.h"
#include "lgc.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#include "lstring.h"
#include "ltable.h"
#include "ltm.h"
#include "lvm.h"
const char lua_ident[] = "$Lua: " LUA_VERSION " " LUA_COPYRIGHT " $\n"
"$Authors: " LUA_AUTHORS " $";
#define Index(L,i) ((i) >= 0 ? (L->Cbase+((i)-1)) : (L->top+(i)))
#define api_incr_top(L) (++L->top)
TObject *luaA_index (lua_State *L, int index) {
return Index(L, index);
}
void luaA_pushobject (lua_State *L, const TObject *o) {
*L->top = *o;
incr_top;
}
int lua_stackspace (lua_State *L) {
return (L->stack_last - L->top);
}
/*
** basic stack manipulation
*/
int lua_gettop (lua_State *L) {
return (L->top - L->Cbase);
}
void lua_settop (lua_State *L, int index) {
if (index >= 0)
luaD_adjusttop(L, L->Cbase, index);
else
L->top += index; /* index is negative */
}
void lua_pushobject (lua_State *L, int index) {
*L->top = *Index(L, index);
api_incr_top(L);
}
/*
** access functions (stack -> C)
*/
#define btest(L,i,value,default) { \
StkId o; \
if ((i) >= 0) { \
o = L->Cbase+((i)-1); \
if (o >= L->top) return (default); \
} \
else o = L->top+(i); \
return (value); }
#define access(L,i,test,default,value) { \
StkId o; \
if ((i) >= 0) { \
o = L->Cbase+((i)-1); \
if (o >= L->top) return (default); \
} \
else o = L->top+(i); \
return ((test) ? (value) : (default)); }
const char *lua_type (lua_State *L, int index) {
btest(L, index, luaO_typename(o), "NO VALUE");
}
int lua_iscfunction (lua_State *L, int index) {
btest(L, index, (ttype(o) == TAG_CCLOSURE), 0);
}
int lua_isnumber (lua_State *L, int index) {
btest(L, index, (tonumber(Index(L, index)) == 0), 0);
}
int lua_tag (lua_State *L, int index) {
btest(L, index,
((ttype(o) == TAG_USERDATA) ? tsvalue(o)->u.d.tag : luaT_effectivetag(L, o)),
-1);
}
int lua_equal(lua_State *L, int index1, int index2) {
StkId o1 = Index(L, index1);
StkId o2 = Index(L, index2);
if (o1 >= L->top || o2 >= L->top) return 0; /* index out-of-range */
else return luaO_equalObj(o1, o2);
}
double lua_tonumber (lua_State *L, int index) {
access(L, index, (tonumber(o) == 0), 0.0, nvalue(o));
}
const char *lua_tostring (lua_State *L, int index) {
luaC_checkGC(L); /* `tostring' may create a new string */
access(L, index, (tostring(L, o) == 0), NULL, svalue(o));
}
size_t lua_strlen (lua_State *L, int index) {
access(L, index, (tostring(L, o) == 0), 0, tsvalue(o)->u.s.len);
}
lua_CFunction lua_tocfunction (lua_State *L, int index) {
access(L, index, (ttype(o) == TAG_CCLOSURE), NULL, clvalue(o)->f.c);
}
void *lua_touserdata (lua_State *L, int index) {
access(L, index, (ttype(o) == TAG_USERDATA), NULL, tsvalue(o)->u.d.value);
}
/*
** push functions (C -> stack)
*/
void lua_pushnil (lua_State *L) {
ttype(L->top) = TAG_NIL;
api_incr_top(L);
}
void lua_pushnumber (lua_State *L, double n) {
ttype(L->top) = TAG_NUMBER;
nvalue(L->top) = n;
api_incr_top(L);
}
void lua_pushlstring (lua_State *L, const char *s, size_t len) {
luaC_checkGC(L);
tsvalue(L->top) = luaS_newlstr(L, s, len);
ttype(L->top) = TAG_STRING;
api_incr_top(L);
}
void lua_pushstring (lua_State *L, const char *s) {
if (s == NULL)
lua_pushnil(L);
else
lua_pushlstring(L, s, strlen(s));
}
void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
luaC_checkGC(L);
luaV_Cclosure(L, fn, n);
}
void lua_pushusertag (lua_State *L, void *u, int tag) { /* ORDER LUA_T */
luaC_checkGC(L);
if (tag != LUA_ANYTAG && tag != TAG_USERDATA && tag < NUM_TAGS)
luaL_verror(L, "invalid tag for a userdata (%d)", tag);
tsvalue(L->top) = luaS_createudata(L, u, tag);
ttype(L->top) = TAG_USERDATA;
api_incr_top(L);
}
/*
** get functions (Lua -> stack)
*/
void lua_getglobal (lua_State *L, const char *name) {
luaV_getglobal(L, luaS_new(L, name), L->top++);
}
void lua_gettable (lua_State *L) {
luaV_gettable(L, L->top--);
}
void lua_rawget (lua_State *L) {
if (ttype(L->top - 2) != TAG_TABLE)
lua_error(L, "indexed expression not a table");
*(L->top - 2) = *luaH_get(L, hvalue(L->top - 2), L->top - 1);
L->top--;
}
void lua_getglobals (lua_State *L) {
hvalue(L->top) = L->gt;
ttype(L->top) = TAG_TABLE;
api_incr_top(L);
}
void lua_gettagmethod (lua_State *L, int tag, const char *event) {
*L->top = *luaT_gettagmethod(L, tag, event);
api_incr_top(L);
}
int lua_getref (lua_State *L, int ref) {
if (ref == LUA_REFNIL)
ttype(L->top) = TAG_NIL;
else if (0 <= ref && ref < L->refSize &&
(L->refArray[ref].st == LOCK || L->refArray[ref].st == HOLD))
*L->top = L->refArray[ref].o;
else
return 0;
api_incr_top(L);
return 1;
}
void lua_newtable (lua_State *L) {
luaC_checkGC(L);
hvalue(L->top) = luaH_new(L, 0);
ttype(L->top) = TAG_TABLE;
api_incr_top(L);
}
/*
** set functions (stack -> Lua)
*/
void lua_setglobal (lua_State *L, const char *name) {
luaV_setglobal(L, luaS_new(L, name), L->top--);
}
void lua_settable (lua_State *L) {
StkId top = L->top;
luaV_settable(L, top-3, top);
L->top = top-3; /* pop table, index, and value */
}
void lua_rawset (lua_State *L) {
if (ttype(L->top-3) != TAG_TABLE)
lua_error(L, "indexed expression not a table");
*luaH_set(L, hvalue(L->top-3), L->top-2) = *(L->top-1);
L->top -= 3;
}
void lua_setglobals (lua_State *L) {
TObject *newtable = --L->top;
if (ttype(newtable) != TAG_TABLE)
lua_error(L, "Lua API error - invalid value for global table");
L->gt = hvalue(newtable);
}
void lua_settagmethod (lua_State *L, int tag, const char *event) {
TObject *method = L->top - 1;
if (ttype(method) != TAG_NIL &&
ttype(method) != TAG_CCLOSURE &&
ttype(method) != TAG_LCLOSURE)
lua_error(L, "Lua API error - tag method must be a function or nil");
luaT_settagmethod(L, tag, event, method);
}
int lua_ref (lua_State *L, int lock) {
int ref;
if (ttype(L->top-1) == TAG_NIL)
ref = LUA_REFNIL;
else {
if (L->refFree != NONEXT) { /* is there a free place? */
ref = L->refFree;
L->refFree = L->refArray[ref].st;
}
else { /* no more free places */
luaM_growvector(L, L->refArray, L->refSize, 1, struct Ref,
"reference table overflow", MAX_INT);
ref = L->refSize++;
}
L->refArray[ref].o = *(L->top-1);
L->refArray[ref].st = lock ? LOCK : HOLD;
}
L->top--;
return ref;
}
/*
** miscellaneous functions
*/
void lua_settag (lua_State *L, int tag) {
luaT_realtag(L, tag);
switch (ttype(L->top-1)) {
case TAG_TABLE:
hvalue(L->top-1)->htag = tag;
break;
case TAG_USERDATA:
tsvalue(L->top-1)->u.d.tag = tag;
break;
default:
luaL_verror(L, "cannot change the tag of a %.20s",
luaO_typename(L->top-1));
}
L->top--;
}
void lua_unref (lua_State *L, int ref) {
if (ref >= 0) {
if (ref >= L->refSize || L->refArray[ref].st >= 0)
lua_error(L, "Lua API error - "
"invalid argument for function `lua_unref'");
L->refArray[ref].st = L->refFree;
L->refFree = ref;
}
}
int lua_next (lua_State *L) {
const TObject *t = Index(L, -2);
Node *n;
if (ttype(t) != TAG_TABLE)
lua_error(L, "Lua API error - object is not a table in `lua_next'");
n = luaH_next(L, hvalue(t), Index(L, -1));
if (n) {
*(L->top-1) = *key(n);
*L->top = *val(n);
api_incr_top(L);
return 1;
}
else { /* no more elements */
L->top -= 2; /* remove key and table */
return 0;
}
}