lua/lapi.c
1998-03-06 13:54:42 -03:00

632 lines
13 KiB
C

/*
** $Id: lapi.c,v 1.21 1998/02/12 19:23:32 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
#include <stdlib.h>
#include <string.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 "lua.h"
#include "luadebug.h"
#include "lvm.h"
char lua_ident[] = "$Lua: " LUA_VERSION " " LUA_COPYRIGHT " $\n"
"$Autores: " LUA_AUTHORS " $";
TObject *luaA_Address (lua_Object o)
{
return Address(o);
}
static int normalized_type (TObject *o)
{
int t = ttype(o);
switch (t) {
case LUA_T_PMARK:
return LUA_T_PROTO;
case LUA_T_CMARK:
return LUA_T_CPROTO;
case LUA_T_CLMARK:
return LUA_T_CLOSURE;
default:
return t;
}
}
static void set_normalized (TObject *d, TObject *s)
{
d->value = s->value;
d->ttype = normalized_type(s);
}
static TObject *luaA_protovalue (TObject *o)
{
return (normalized_type(o) == LUA_T_CLOSURE) ? protovalue(o) : o;
}
void luaA_packresults (void)
{
luaV_pack(L->Cstack.lua2C, L->Cstack.num, L->stack.top);
incr_top;
}
int luaA_passresults (void)
{
luaD_checkstack(L->Cstack.num);
memcpy(L->stack.top, L->Cstack.lua2C+L->stack.stack,
L->Cstack.num*sizeof(TObject));
L->stack.top += L->Cstack.num;
return L->Cstack.num;
}
static void checkCparams (int nParams)
{
if (L->stack.top-L->stack.stack < L->Cstack.base+nParams)
lua_error("API error - wrong number of arguments in C2lua stack");
}
static lua_Object put_luaObject (TObject *o)
{
luaD_openstack((L->stack.top-L->stack.stack)-L->Cstack.base);
L->stack.stack[L->Cstack.base++] = *o;
return L->Cstack.base; /* this is +1 real position (see Ref) */
}
static lua_Object put_luaObjectonTop (void)
{
luaD_openstack((L->stack.top-L->stack.stack)-L->Cstack.base);
L->stack.stack[L->Cstack.base++] = *(--L->stack.top);
return L->Cstack.base; /* this is +1 real position (see Ref) */
}
lua_Object lua_pop (void)
{
checkCparams(1);
return put_luaObjectonTop();
}
/*
** Get a parameter, returning the object handle or LUA_NOOBJECT on error.
** 'number' must be 1 to get the first parameter.
*/
lua_Object lua_lua2C (int number)
{
if (number <= 0 || number > L->Cstack.num) return LUA_NOOBJECT;
/* Ref(L->stack.stack+(L->Cstack.lua2C+number-1)) ==
L->stack.stack+(L->Cstack.lua2C+number-1)-L->stack.stack+1 == */
return L->Cstack.lua2C+number;
}
int lua_callfunction (lua_Object function)
{
if (function == LUA_NOOBJECT)
return 1;
else {
luaD_openstack((L->stack.top-L->stack.stack)-L->Cstack.base);
set_normalized(L->stack.stack+L->Cstack.base, Address(function));
return luaD_protectedrun(MULT_RET);
}
}
lua_Object lua_gettagmethod (int tag, char *event)
{
return put_luaObject(luaT_gettagmethod(tag, event));
}
lua_Object lua_settagmethod (int tag, char *event)
{
checkCparams(1);
luaT_settagmethod(tag, event, L->stack.top-1);
return put_luaObjectonTop();
}
lua_Object lua_seterrormethod (void)
{
TObject temp = L->errorim;
checkCparams(1);
L->errorim = *(--L->stack.top);
return put_luaObject(&temp);
}
lua_Object lua_gettable (void)
{
checkCparams(2);
luaV_gettable();
return put_luaObjectonTop();
}
lua_Object lua_rawgettable (void)
{
checkCparams(2);
if (ttype(L->stack.top-2) != LUA_T_ARRAY)
lua_error("indexed expression not a table in rawgettable");
else {
TObject *h = luaH_get(avalue(L->stack.top-2), L->stack.top-1);
--L->stack.top;
if (h != NULL)
*(L->stack.top-1) = *h;
else
ttype(L->stack.top-1) = LUA_T_NIL;
}
return put_luaObjectonTop();
}
void lua_settable (void)
{
checkCparams(3);
luaV_settable(L->stack.top-3, 1);
}
void lua_rawsettable (void)
{
checkCparams(3);
luaV_settable(L->stack.top-3, 0);
}
lua_Object lua_createtable (void)
{
TObject o;
luaC_checkGC();
avalue(&o) = luaH_new(0);
ttype(&o) = LUA_T_ARRAY;
return put_luaObject(&o);
}
lua_Object lua_getglobal (char *name)
{
luaD_checkstack(2); /* may need that to call T.M. */
luaV_getglobal(luaS_new(name));
return put_luaObjectonTop();
}
lua_Object lua_rawgetglobal (char *name)
{
TaggedString *ts = luaS_new(name);
return put_luaObject(&ts->u.s.globalval);
}
void lua_setglobal (char *name)
{
checkCparams(1);
luaD_checkstack(2); /* may need that to call T.M. */
luaV_setglobal(luaS_new(name));
}
void lua_rawsetglobal (char *name)
{
TaggedString *ts = luaS_new(name);
checkCparams(1);
luaS_rawsetglobal(ts, --L->stack.top);
}
int lua_isnil (lua_Object o)
{
return (o!= LUA_NOOBJECT) && (ttype(Address(o)) == LUA_T_NIL);
}
int lua_istable (lua_Object o)
{
return (o!= LUA_NOOBJECT) && (ttype(Address(o)) == LUA_T_ARRAY);
}
int lua_isuserdata (lua_Object o)
{
return (o!= LUA_NOOBJECT) && (ttype(Address(o)) == LUA_T_USERDATA);
}
int lua_iscfunction (lua_Object o)
{
return (lua_tag(o) == LUA_T_CPROTO);
}
int lua_isnumber (lua_Object o)
{
return (o!= LUA_NOOBJECT) && (tonumber(Address(o)) == 0);
}
int lua_isstring (lua_Object o)
{
int t = lua_tag(o);
return (t == LUA_T_STRING) || (t == LUA_T_NUMBER);
}
int lua_isfunction (lua_Object o)
{
int t = lua_tag(o);
return (t == LUA_T_PROTO) || (t == LUA_T_CPROTO);
}
double lua_getnumber (lua_Object object)
{
if (object == LUA_NOOBJECT) return 0.0;
if (tonumber(Address(object))) return 0.0;
else return (nvalue(Address(object)));
}
char *lua_getstring (lua_Object object)
{
luaC_checkGC(); /* "tostring" may create a new string */
if (object == LUA_NOOBJECT || tostring(Address(object)))
return NULL;
else return (svalue(Address(object)));
}
long lua_getstrlen (lua_Object object)
{
luaC_checkGC(); /* "tostring" may create a new string */
if (object == LUA_NOOBJECT || tostring(Address(object)))
return 0L;
else return (tsvalue(Address(object))->u.s.len);
}
void *lua_getuserdata (lua_Object object)
{
if (object == LUA_NOOBJECT || ttype(Address(object)) != LUA_T_USERDATA)
return NULL;
else return tsvalue(Address(object))->u.d.v;
}
lua_CFunction lua_getcfunction (lua_Object object)
{
if (!lua_iscfunction(object))
return NULL;
else return fvalue(luaA_protovalue(Address(object)));
}
void lua_pushnil (void)
{
ttype(L->stack.top) = LUA_T_NIL;
incr_top;
}
void lua_pushnumber (double n)
{
ttype(L->stack.top) = LUA_T_NUMBER;
nvalue(L->stack.top) = n;
incr_top;
}
void lua_pushlstr (char *s, long len)
{
tsvalue(L->stack.top) = luaS_newlstr(s, len);
ttype(L->stack.top) = LUA_T_STRING;
incr_top;
luaC_checkGC();
}
void lua_pushstring (char *s)
{
if (s == NULL)
lua_pushnil();
else
lua_pushlstr(s, strlen(s));
}
void lua_pushCclosure (lua_CFunction fn, int n)
{
if (fn == NULL)
lua_error("API error - attempt to push a NULL Cfunction");
checkCparams(n);
ttype(L->stack.top) = LUA_T_CPROTO;
fvalue(L->stack.top) = fn;
incr_top;
luaV_closure(n);
luaC_checkGC();
}
void lua_pushusertag (void *u, int tag)
{
if (tag < 0 && tag != LUA_ANYTAG)
luaT_realtag(tag); /* error if tag is not valid */
tsvalue(L->stack.top) = luaS_createudata(u, tag);
ttype(L->stack.top) = LUA_T_USERDATA;
incr_top;
luaC_checkGC();
}
void luaA_pushobject (TObject *o)
{
*L->stack.top = *o;
incr_top;
}
void lua_pushobject (lua_Object o)
{
if (o == LUA_NOOBJECT)
lua_error("API error - attempt to push a NOOBJECT");
else {
set_normalized(L->stack.top, Address(o));
incr_top;
}
}
int lua_tag (lua_Object lo)
{
if (lo == LUA_NOOBJECT)
return LUA_T_NIL;
else {
TObject *o = Address(lo);
int t;
switch (t = ttype(o)) {
case LUA_T_USERDATA:
return o->value.ts->u.d.tag;
case LUA_T_ARRAY:
return o->value.a->htag;
case LUA_T_PMARK:
return LUA_T_PROTO;
case LUA_T_CMARK:
return LUA_T_CPROTO;
case LUA_T_CLOSURE: case LUA_T_CLMARK:
return o->value.cl->consts[0].ttype;
#ifdef DEBUG
case LUA_T_LINE:
lua_error("internal error");
#endif
default:
return t;
}
}
}
void lua_settag (int tag)
{
checkCparams(1);
luaT_realtag(tag);
switch (ttype(L->stack.top-1)) {
case LUA_T_ARRAY:
(L->stack.top-1)->value.a->htag = tag;
break;
case LUA_T_USERDATA:
(L->stack.top-1)->value.ts->u.d.tag = tag;
break;
default:
luaL_verror("cannot change the tag of a %.20s",
luaO_typenames[-ttype((L->stack.top-1))]);
}
L->stack.top--;
}
/*
** =======================================================
** Debug interface
** =======================================================
*/
/* Hooks */
lua_CHFunction lua_callhook = NULL;
lua_LHFunction lua_linehook = NULL;
lua_Function lua_stackedfunction (int level)
{
StkId i;
for (i = (L->stack.top-1)-L->stack.stack; i>=0; i--) {
int t = L->stack.stack[i].ttype;
if (t == LUA_T_CLMARK || t == LUA_T_PMARK || t == LUA_T_CMARK)
if (level-- == 0)
return Ref(L->stack.stack+i);
}
return LUA_NOOBJECT;
}
int lua_currentline (lua_Function func)
{
TObject *f = Address(func);
return (f+1 < L->stack.top && (f+1)->ttype == LUA_T_LINE) ?
(f+1)->value.i : -1;
}
lua_Object lua_getlocal (lua_Function func, int local_number, char **name)
{
/* check whether func is a Lua function */
if (lua_tag(func) != LUA_T_PROTO)
return LUA_NOOBJECT;
else {
TObject *f = Address(func);
TProtoFunc *fp = luaA_protovalue(f)->value.tf;
*name = luaF_getlocalname(fp, local_number, lua_currentline(func));
if (*name) {
/* if "*name", there must be a LUA_T_LINE */
/* therefore, f+2 points to function base */
return Ref((f+2)+(local_number-1));
}
else
return LUA_NOOBJECT;
}
}
int lua_setlocal (lua_Function func, int local_number)
{
/* check whether func is a Lua function */
if (lua_tag(func) != LUA_T_PROTO)
return 0;
else {
TObject *f = Address(func);
TProtoFunc *fp = luaA_protovalue(f)->value.tf;
char *name = luaF_getlocalname(fp, local_number, lua_currentline(func));
checkCparams(1);
--L->stack.top;
if (name) {
/* if "name", there must be a LUA_T_LINE */
/* therefore, f+2 points to function base */
*((f+2)+(local_number-1)) = *L->stack.top;
return 1;
}
else
return 0;
}
}
void lua_funcinfo (lua_Object func, char **filename, int *linedefined)
{
if (!lua_isfunction(func))
lua_error("API - `funcinfo' called with a non-function value");
else {
TObject *f = luaA_protovalue(Address(func));
if (normalized_type(f) == LUA_T_PROTO) {
*filename = tfvalue(f)->fileName->str;
*linedefined = tfvalue(f)->lineDefined;
}
else {
*filename = "(C)";
*linedefined = -1;
}
}
}
static int checkfunc (TObject *o)
{
return luaO_equalObj(o, L->stack.top);
}
char *lua_getobjname (lua_Object o, char **name)
{ /* try to find a name for given function */
set_normalized(L->stack.top, Address(o)); /* to be accessed by "checkfunc */
if ((*name = luaT_travtagmethods(checkfunc)) != NULL)
return "tag-method";
else if ((*name = luaS_travsymbol(checkfunc)) != NULL)
return "global";
else return "";
}
/*
** =======================================================
** BLOCK mechanism
** =======================================================
*/
void lua_beginblock (void)
{
if (L->numCblocks >= MAX_C_BLOCKS)
lua_error("too many nested blocks");
L->Cblocks[L->numCblocks] = L->Cstack;
L->numCblocks++;
}
void lua_endblock (void)
{
--L->numCblocks;
L->Cstack = L->Cblocks[L->numCblocks];
luaD_adjusttop(L->Cstack.base);
}
int lua_ref (int lock)
{
int ref;
checkCparams(1);
ref = luaC_ref(L->stack.top-1, lock);
L->stack.top--;
return ref;
}
lua_Object lua_getref (int ref)
{
TObject *o = luaC_getref(ref);
return (o ? put_luaObject(o) : LUA_NOOBJECT);
}
/*
** =======================================================
** Derived functions
** =======================================================
*/
int (lua_call) (char *name) { return lua_call(name); }
void (lua_pushref) (int ref) { lua_pushref(ref); }
int (lua_refobject) (lua_Object o, int l) { return lua_refobject(o, l); }
void (lua_register) (char *n, lua_CFunction f) { lua_register(n, f); }
void (lua_pushuserdata) (void *u) { lua_pushuserdata(u); }
void (lua_pushcfunction) (lua_CFunction f) { lua_pushcfunction(f); }
int (lua_clonetag) (int t) { return lua_clonetag(t); }
#ifdef LUA_COMPAT2_5
/*
** API: set a function as a fallback
*/
static void do_unprotectedrun (lua_CFunction f, int nParams, int nResults)
{
StkId base = (L->stack.top-L->stack.stack)-nParams;
luaD_openstack(nParams);
L->stack.stack[base].ttype = LUA_T_CPROTO;
L->stack.stack[base].value.f = f;
luaD_call(base+1, nResults);
}
lua_Object lua_setfallback (char *name, lua_CFunction fallback)
{
lua_pushstring(name);
lua_pushcfunction(fallback);
do_unprotectedrun(luaT_setfallback, 2, 1);
return put_luaObjectonTop();
}
#endif