lua/lapi.c
2002-04-16 14:08:28 -03:00

702 lines
14 KiB
C

/*
** $Id: lapi.c,v 1.183 2002/04/05 18:54:31 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
#include <string.h>
#include "lua.h"
#include "lapi.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 " $\n"
"$URL: www.lua.org $\n";
#ifndef api_check
#define api_check(L, o) ((void)1)
#endif
#define api_checknelems(L, n) api_check(L, (n) <= (L->top - L->ci->base))
#define api_incr_top(L) (api_check(L, L->top<L->ci->top), L->top++)
static TObject *negindex (lua_State *L, int index) {
if (index > LUA_REGISTRYINDEX) {
api_check(L, index != 0 && -index <= L->top - L->ci->base);
return L->top+index;
}
else switch (index) { /* pseudo-indices */
case LUA_REGISTRYINDEX: return registry(L);
case LUA_GLOBALSINDEX: return gt(L);
default: {
TObject *func = (L->ci->base - 1);
index = LUA_GLOBALSINDEX - index;
api_check(L, iscfunction(func) && index <= clvalue(func)->c.nupvalues);
return &clvalue(func)->c.upvalue[index-1];
}
}
}
#define luaA_index(L, index) \
( (index > 0) ? \
(api_check(L, index <= L->top - L->ci->base), L->ci->base+index-1) : \
negindex(L, index))
static TObject *luaA_indexAcceptable (lua_State *L, int index) {
if (index > 0) {
TObject *o = L->ci->base+(index-1);
api_check(L, index <= L->stack_last - L->ci->base);
if (o >= L->top) return NULL;
else return o;
}
else
return negindex(L, index);
}
void luaA_pushobject (lua_State *L, const TObject *o) {
setobj(L->top, o);
incr_top(L);
}
LUA_API int lua_checkstack (lua_State *L, int size) {
int res;
lua_lock(L);
if ((L->top - L->ci->base + size) > LUA_MAXCSTACK)
res = 0; /* stack overflow */
else {
luaD_checkstack(L, size);
if (L->ci->top < L->top + size)
L->ci->top = L->top + size;
res = 1;
}
lua_unlock(L);
return res;
}
LUA_API lua_CFunction lua_setpanicf (lua_State *L, lua_CFunction panicf) {
lua_CFunction old;
lua_lock(L);
old = G(L)->panic;
G(L)->panic = panicf;
lua_unlock(L);
return old;
}
/*
** basic stack manipulation
*/
LUA_API int lua_gettop (lua_State *L) {
return (L->top - L->ci->base);
}
LUA_API void lua_settop (lua_State *L, int index) {
lua_lock(L);
if (index >= 0) {
api_check(L, index <= L->stack_last - L->ci->base);
while (L->top < L->ci->base + index)
setnilvalue(L->top++);
L->top = L->ci->base + index;
}
else {
api_check(L, -(index+1) <= (L->top - L->ci->base));
L->top += index+1; /* `subtract' index (index is negative) */
}
lua_unlock(L);
}
LUA_API void lua_remove (lua_State *L, int index) {
StkId p;
lua_lock(L);
p = luaA_index(L, index);
while (++p < L->top) setobj(p-1, p);
L->top--;
lua_unlock(L);
}
LUA_API void lua_insert (lua_State *L, int index) {
StkId p;
StkId q;
lua_lock(L);
p = luaA_index(L, index);
for (q = L->top; q>p; q--) setobj(q, q-1);
setobj(p, L->top);
lua_unlock(L);
}
LUA_API void lua_replace (lua_State *L, int index) {
lua_lock(L);
api_checknelems(L, 1);
setobj(luaA_index(L, index), L->top - 1);
L->top--;
lua_unlock(L);
}
LUA_API void lua_pushvalue (lua_State *L, int index) {
lua_lock(L);
setobj(L->top, luaA_index(L, index));
api_incr_top(L);
lua_unlock(L);
}
/*
** access functions (stack -> C)
*/
LUA_API int lua_type (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL) ? LUA_TNONE : ttype(o);
}
LUA_API const char *lua_typename (lua_State *L, int t) {
UNUSED(L);
return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
}
LUA_API int lua_iscfunction (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL) ? 0 : iscfunction(o);
}
LUA_API int lua_isnumber (lua_State *L, int index) {
TObject n;
const TObject *o = luaA_indexAcceptable(L, index);
return (o != NULL && tonumber(o, &n));
}
LUA_API int lua_isstring (lua_State *L, int index) {
int t = lua_type(L, index);
return (t == LUA_TSTRING || t == LUA_TNUMBER);
}
LUA_API int lua_equal (lua_State *L, int index1, int index2) {
StkId o1 = luaA_indexAcceptable(L, index1);
StkId o2 = luaA_indexAcceptable(L, index2);
return (o1 == NULL || o2 == NULL) ? 0 /* index out of range */
: luaO_equalObj(o1, o2);
}
LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
StkId o1, o2;
int i;
lua_lock(L); /* may call tag method */
o1 = luaA_indexAcceptable(L, index1);
o2 = luaA_indexAcceptable(L, index2);
i = (o1 == NULL || o2 == NULL) ? 0 /* index out-of-range */
: luaV_lessthan(L, o1, o2);
lua_unlock(L);
return i;
}
LUA_API lua_Number lua_tonumber (lua_State *L, int index) {
TObject n;
const TObject *o = luaA_indexAcceptable(L, index);
if (o != NULL && tonumber(o, &n))
return nvalue(o);
else
return 0;
}
LUA_API int lua_toboolean (lua_State *L, int index) {
const TObject *o = luaA_indexAcceptable(L, index);
return (o != NULL) && !l_isfalse(o);
}
LUA_API const char *lua_tostring (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
if (o == NULL)
return NULL;
else if (ttype(o) == LUA_TSTRING)
return svalue(o);
else {
const char *s;
lua_lock(L); /* `luaV_tostring' may create a new string */
s = (luaV_tostring(L, o) ? svalue(o) : NULL);
lua_unlock(L);
return s;
}
}
LUA_API size_t lua_strlen (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
if (o == NULL)
return 0;
else if (ttype(o) == LUA_TSTRING)
return tsvalue(o)->tsv.len;
else {
size_t l;
lua_lock(L); /* `luaV_tostring' may create a new string */
l = (luaV_tostring(L, o) ? tsvalue(o)->tsv.len : 0);
lua_unlock(L);
return l;
}
}
LUA_API lua_CFunction lua_tocfunction (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL || !iscfunction(o)) ? NULL : clvalue(o)->c.f;
}
LUA_API void *lua_touserdata (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
if (o == NULL) return NULL;
switch (ttype(o)) {
case LUA_TUSERDATA: return (uvalue(o) + 1);
case LUA_TUDATAVAL: return pvalue(o);
default: return NULL;
}
}
LUA_API const void *lua_topointer (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
if (o == NULL) return NULL;
else {
switch (ttype(o)) {
case LUA_TTABLE: return hvalue(o);
case LUA_TFUNCTION: return clvalue(o);
default: return NULL;
}
}
}
/*
** push functions (C -> stack)
*/
LUA_API void lua_pushnil (lua_State *L) {
lua_lock(L);
setnilvalue(L->top);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
lua_lock(L);
setnvalue(L->top, n);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
lua_lock(L);
setsvalue(L->top, luaS_newlstr(L, s, len));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushstring (lua_State *L, const char *s) {
if (s == NULL)
lua_pushnil(L);
else
lua_pushlstring(L, s, strlen(s));
}
LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
Closure *cl;
lua_lock(L);
api_checknelems(L, n);
cl = luaF_newCclosure(L, n);
cl->c.f = fn;
L->top -= n;
while (n--)
setobj(&cl->c.upvalue[n], L->top+n);
setclvalue(L->top, cl);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushboolean (lua_State *L, int b) {
lua_lock(L);
setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushudataval (lua_State *L, void *p) {
lua_lock(L);
setpvalue(L->top, p);
api_incr_top(L);
lua_unlock(L);
}
/*
** get functions (Lua -> stack)
*/
LUA_API void lua_gettable (lua_State *L, int index) {
StkId t;
lua_lock(L);
t = luaA_index(L, index);
luaV_gettable(L, t, L->top-1, L->top-1);
lua_unlock(L);
}
LUA_API void lua_rawget (lua_State *L, int index) {
StkId t;
lua_lock(L);
t = luaA_index(L, index);
api_check(L, ttype(t) == LUA_TTABLE);
setobj(L->top - 1, luaH_get(hvalue(t), L->top - 1));
lua_unlock(L);
}
LUA_API void lua_rawgeti (lua_State *L, int index, int n) {
StkId o;
lua_lock(L);
o = luaA_index(L, index);
api_check(L, ttype(o) == LUA_TTABLE);
setobj(L->top, luaH_getnum(hvalue(o), n));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_newtable (lua_State *L) {
lua_lock(L);
sethvalue(L->top, luaH_new(L, 0, 0));
api_incr_top(L);
lua_unlock(L);
}
LUA_API int lua_getmetatable (lua_State *L, int objindex) {
StkId obj;
Table *mt;
int res;
lua_lock(L);
obj = luaA_indexAcceptable(L, objindex);
switch (ttype(obj)) {
case LUA_TTABLE:
mt = hvalue(obj)->metatable;
break;
case LUA_TUSERDATA:
mt = uvalue(obj)->uv.metatable;
break;
default:
mt = hvalue(defaultmeta(L));
}
if (mt == hvalue(defaultmeta(L)))
res = 0;
else {
sethvalue(L->top, mt);
api_incr_top(L);
res = 1;
}
lua_unlock(L);
return res;
}
/*
** set functions (stack -> Lua)
*/
LUA_API void lua_settable (lua_State *L, int index) {
StkId t;
lua_lock(L);
api_checknelems(L, 2);
t = luaA_index(L, index);
luaV_settable(L, t, L->top - 2, L->top - 1);
L->top -= 2; /* pop index and value */
lua_unlock(L);
}
LUA_API void lua_rawset (lua_State *L, int index) {
StkId t;
lua_lock(L);
api_checknelems(L, 2);
t = luaA_index(L, index);
api_check(L, ttype(t) == LUA_TTABLE);
luaH_set(L, hvalue(t), L->top-2, L->top-1);
L->top -= 2;
lua_unlock(L);
}
LUA_API void lua_rawseti (lua_State *L, int index, int n) {
StkId o;
lua_lock(L);
api_checknelems(L, 1);
o = luaA_index(L, index);
api_check(L, ttype(o) == LUA_TTABLE);
luaH_setnum(L, hvalue(o), n, L->top-1);
L->top--;
lua_unlock(L);
}
LUA_API void lua_setmetatable (lua_State *L, int objindex) {
StkId obj, mt;
lua_lock(L);
api_checknelems(L, 1);
obj = luaA_index(L, objindex);
mt = --L->top;
if (ttype(mt) == LUA_TNIL)
mt = defaultmeta(L);
api_check(L, ttype(mt) == LUA_TTABLE);
switch (ttype(obj)) {
case LUA_TTABLE:
hvalue(obj)->metatable = hvalue(mt);
break;
case LUA_TUSERDATA:
uvalue(obj)->uv.metatable = hvalue(mt);
break;
default:
luaO_verror(L, "cannot change the meta table of a %.20s",
luaT_typenames[ttype(obj)]);
}
lua_unlock(L);
}
/*
** `do' functions (run Lua code)
*/
LUA_API void lua_rawcall (lua_State *L, int nargs, int nresults) {
StkId func;
lua_lock(L);
api_checknelems(L, nargs+1);
func = L->top - (nargs+1);
luaD_call(L, func, nresults);
lua_unlock(L);
}
LUA_API int lua_dofile (lua_State *L, const char *filename) {
int status;
status = lua_loadfile(L, filename);
if (status == 0) /* parse OK? */
status = lua_call(L, 0, LUA_MULTRET); /* call main */
return status;
}
LUA_API int lua_dobuffer (lua_State *L, const char *buff, size_t size,
const char *name) {
int status;
status = lua_loadbuffer(L, buff, size, name);
if (status == 0) /* parse OK? */
status = lua_call(L, 0, LUA_MULTRET); /* call main */
return status;
}
LUA_API int lua_dostring (lua_State *L, const char *str) {
return lua_dobuffer(L, str, strlen(str), str);
}
/*
** Garbage-collection functions
*/
/* GC values are expressed in Kbytes: #bytes/2^10 */
#define GCscale(x) (cast(int, (x)>>10))
#define GCunscale(x) (cast(lu_mem, (x)<<10))
LUA_API int lua_getgcthreshold (lua_State *L) {
int threshold;
lua_lock(L);
threshold = GCscale(G(L)->GCthreshold);
lua_unlock(L);
return threshold;
}
LUA_API int lua_getgccount (lua_State *L) {
int count;
lua_lock(L);
count = GCscale(G(L)->nblocks);
lua_unlock(L);
return count;
}
LUA_API void lua_setgcthreshold (lua_State *L, int newthreshold) {
lua_lock(L);
if (newthreshold > GCscale(ULONG_MAX))
G(L)->GCthreshold = ULONG_MAX;
else
G(L)->GCthreshold = GCunscale(newthreshold);
luaC_checkGC(L);
lua_unlock(L);
}
/*
** miscellaneous functions
*/
LUA_API void lua_error (lua_State *L, const char *s) {
lua_lock(L);
luaD_error(L, s);
lua_unlock(L);
}
LUA_API int lua_next (lua_State *L, int index) {
StkId t;
int more;
lua_lock(L);
t = luaA_index(L, index);
api_check(L, ttype(t) == LUA_TTABLE);
more = luaH_next(L, hvalue(t), L->top - 1);
if (more) {
api_incr_top(L);
}
else /* no more elements */
L->top -= 1; /* remove key */
lua_unlock(L);
return more;
}
LUA_API int lua_getn (lua_State *L, int index) {
StkId t;
const TObject *value;
int n;
lua_lock(L);
t = luaA_index(L, index);
api_check(L, ttype(t) == LUA_TTABLE);
value = luaH_getstr(hvalue(t), luaS_newliteral(L, "n")); /* = t.n */
if (ttype(value) == LUA_TNUMBER)
lua_number2int(n, nvalue(value));
else {
Node *nd;
Table *a = hvalue(t);
lua_Number max = 0;
int i;
i = sizearray(a);
while (i--) {
if (ttype(&a->array[i]) != LUA_TNIL)
break;
}
max = i+1;
i = sizenode(a);
nd = a->node;
while (i--) {
if (ttype(key(nd)) == LUA_TNUMBER &&
ttype(val(nd)) != LUA_TNIL &&
nvalue(key(nd)) > max)
max = nvalue(key(nd));
nd++;
}
lua_number2int(n, max);
}
lua_unlock(L);
return n;
}
LUA_API void lua_concat (lua_State *L, int n) {
lua_lock(L);
api_checknelems(L, n);
if (n >= 2) {
luaV_strconc(L, n, L->top - L->ci->base - 1);
L->top -= (n-1);
luaC_checkGC(L);
}
else if (n == 0) { /* push null string */
setsvalue(L->top, luaS_newlstr(L, NULL, 0));
api_incr_top(L);
}
/* else n == 1; nothing to do */
lua_unlock(L);
}
LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
Udata *u;
lua_lock(L);
u = luaS_newudata(L, size);
setuvalue(L->top, u);
api_incr_top(L);
lua_unlock(L);
return u + 1;
}
LUA_API int lua_pushupvalues (lua_State *L) {
TObject *func;
int n, i;
lua_lock(L);
func = (L->ci->base - 1);
api_check(L, iscfunction(func));
n = clvalue(func)->c.nupvalues;
luaD_checkstack(L, n + LUA_MINSTACK);
for (i=0; i<n; i++) {
setobj(L->top, &clvalue(func)->c.upvalue[i]);
L->top++;
}
lua_unlock(L);
return n;
}