lua/lapi.c

488 lines
10 KiB
C

/*
** $Id: lapi.c,v 1.117 2001/01/18 15:59:09 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 " $";
#define Index(L,i) ((i) >= 0 ? (L->Cbase+((i)-1)) : (L->top+(i)))
#define api_incr_top(L) incr_top
TObject *luaA_index (lua_State *L, int index) {
return Index(L, index);
}
static TObject *luaA_indexAcceptable (lua_State *L, int index) {
if (index >= 0) {
TObject *o = L->Cbase+(index-1);
if (o >= L->top) return NULL;
else return o;
}
else return L->top+index;
}
void luaA_pushobject (lua_State *L, const TObject *o) {
setobj(L->top, o);
incr_top;
}
LUA_API int lua_stackspace (lua_State *L) {
return (L->stack_last - L->top);
}
/*
** basic stack manipulation
*/
LUA_API int lua_gettop (lua_State *L) {
return (L->top - L->Cbase);
}
LUA_API void lua_settop (lua_State *L, int index) {
if (index >= 0)
luaD_adjusttop(L, L->Cbase, index);
else
L->top = L->top+index+1; /* index is negative */
}
LUA_API void lua_remove (lua_State *L, int index) {
StkId p = luaA_index(L, index);
while (++p < L->top) setobj(p-1, p);
L->top--;
}
LUA_API void lua_insert (lua_State *L, int index) {
StkId p = luaA_index(L, index);
StkId q;
for (q = L->top; q>p; q--) setobj(q, q-1);
setobj(p, L->top);
}
LUA_API void lua_pushvalue (lua_State *L, int index) {
setobj(L->top, luaA_index(L, index));
api_incr_top(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" : luaO_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 *o = luaA_indexAcceptable(L, index);
return (o == NULL) ? 0 : (tonumber(o) == 0);
}
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_tag (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL) ? LUA_NOTAG : luaT_tag(o);
}
LUA_API int lua_equal (lua_State *L, int index1, int index2) {
StkId o1 = luaA_indexAcceptable(L, index1);
StkId o2 = luaA_indexAcceptable(L, index2);
if (o1 == NULL || o2 == NULL) return 0; /* index out-of-range */
else return luaO_equalObj(o1, o2);
}
LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
StkId o1 = luaA_indexAcceptable(L, index1);
StkId o2 = luaA_indexAcceptable(L, index2);
if (o1 == NULL || o2 == NULL) return 0; /* index out-of-range */
else return luaV_lessthan(L, o1, o2, L->top);
}
LUA_API lua_Number lua_tonumber (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL || tonumber(o)) ? 0 : nvalue(o);
}
LUA_API const char *lua_tostring (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL || tostring(L, o)) ? NULL : svalue(o);
}
LUA_API size_t lua_strlen (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL || tostring(L, o)) ? 0 : tsvalue(o)->len;
}
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)->f.c;
}
LUA_API void *lua_touserdata (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
return (o == NULL || ttype(o) != LUA_TUSERDATA) ? NULL :
tsvalue(o)->u.d.value;
}
LUA_API const void *lua_topointer (lua_State *L, int index) {
StkId o = luaA_indexAcceptable(L, index);
if (o == NULL) return NULL;
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) {
setnilvalue(L->top);
api_incr_top(L);
}
LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
setnvalue(L->top, n);
api_incr_top(L);
}
LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
setsvalue(L->top, luaS_newlstr(L, s, len));
api_incr_top(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) {
luaV_Cclosure(L, fn, n);
}
LUA_API void lua_pushusertag (lua_State *L, void *u, int tag) {
/* ORDER LUA_T */
if (!(tag == LUA_ANYTAG || tag == LUA_TUSERDATA || validtag(G(L), tag)))
luaO_verror(L, "invalid tag for a userdata (%d)", tag);
setuvalue(L->top, luaS_createudata(L, u, tag));
api_incr_top(L);
}
/*
** get functions (Lua -> stack)
*/
LUA_API void lua_getglobal (lua_State *L, const char *name) {
StkId top = L->top;
setobj(top, luaV_getglobal(L, luaS_new(L, name)));
L->top = top;
api_incr_top(L);
}
LUA_API void lua_gettable (lua_State *L, int index) {
StkId t = Index(L, index);
StkId top = L->top;
setobj(top-1, luaV_gettable(L, t));
L->top = top; /* tag method may change top */
}
LUA_API void lua_rawget (lua_State *L, int index) {
StkId t = Index(L, index);
lua_assert(ttype(t) == LUA_TTABLE);
setobj(L->top - 1, luaH_get(hvalue(t), L->top - 1));
}
LUA_API void lua_rawgeti (lua_State *L, int index, int n) {
StkId o = Index(L, index);
lua_assert(ttype(o) == LUA_TTABLE);
setobj(L->top, luaH_getnum(hvalue(o), n));
api_incr_top(L);
}
LUA_API void lua_getglobals (lua_State *L) {
sethvalue(L->top, L->gt);
api_incr_top(L);
}
LUA_API int lua_getref (lua_State *L, int ref) {
if (ref == LUA_REFNIL) {
setnilvalue(L->top);
}
else if (0 <= ref && ref < G(L)->nref &&
(G(L)->refArray[ref].st == LOCK || G(L)->refArray[ref].st == HOLD)) {
setobj(L->top, &G(L)->refArray[ref].o);
}
else
return 0;
api_incr_top(L);
return 1;
}
LUA_API void lua_newtable (lua_State *L) {
sethvalue(L->top, luaH_new(L, 0));
api_incr_top(L);
}
/*
** set functions (stack -> Lua)
*/
LUA_API void lua_setglobal (lua_State *L, const char *name) {
StkId top = L->top;
luaV_setglobal(L, luaS_new(L, name));
L->top = top-1; /* remove element from the top */
}
LUA_API void lua_settable (lua_State *L, int index) {
StkId t = Index(L, index);
StkId top = L->top;
luaV_settable(L, t, top-2);
L->top = top-2; /* pop index and value */
}
LUA_API void lua_rawset (lua_State *L, int index) {
StkId t = Index(L, index);
lua_assert(ttype(t) == LUA_TTABLE);
setobj(luaH_set(L, hvalue(t), L->top-2), (L->top-1));
L->top -= 2;
}
LUA_API void lua_rawseti (lua_State *L, int index, int n) {
StkId o = Index(L, index);
lua_assert(ttype(o) == LUA_TTABLE);
setobj(luaH_setnum(L, hvalue(o), n), (L->top-1));
L->top--;
}
LUA_API void lua_setglobals (lua_State *L) {
StkId newtable = --L->top;
lua_assert(ttype(newtable) == LUA_TTABLE);
L->gt = hvalue(newtable);
}
LUA_API int lua_ref (lua_State *L, int lock) {
int ref;
if (ttype(L->top-1) == LUA_TNIL)
ref = LUA_REFNIL;
else {
if (G(L)->refFree != NONEXT) { /* is there a free place? */
ref = G(L)->refFree;
G(L)->refFree = G(L)->refArray[ref].st;
}
else { /* no more free places */
luaM_growvector(L, G(L)->refArray, G(L)->nref, G(L)->sizeref, struct Ref,
MAX_INT, "reference table overflow");
ref = G(L)->nref++;
}
setobj(&G(L)->refArray[ref].o, L->top-1);
G(L)->refArray[ref].st = lock ? LOCK : HOLD;
}
L->top--;
return ref;
}
/*
** "do" functions (run Lua code)
** (most of them are in ldo.c)
*/
LUA_API void lua_rawcall (lua_State *L, int nargs, int nresults) {
luaD_call(L, L->top-(nargs+1), nresults);
}
/*
** Garbage-collection functions
*/
/* GC values are expressed in Kbytes: #bytes/2^10 */
#define GCscale(x) ((int)((x)>>10))
#define GCunscale(x) ((mem_int)(x)<<10)
LUA_API int lua_getgcthreshold (lua_State *L) {
return GCscale(G(L)->GCthreshold);
}
LUA_API int lua_getgccount (lua_State *L) {
return GCscale(G(L)->nblocks);
}
LUA_API void lua_setgcthreshold (lua_State *L, int newthreshold) {
if (newthreshold > GCscale(ULONG_MAX))
G(L)->GCthreshold = ULONG_MAX;
else
G(L)->GCthreshold = GCunscale(newthreshold);
luaC_checkGC(L);
}
/*
** miscellaneous functions
*/
LUA_API void lua_settag (lua_State *L, int tag) {
luaT_realtag(L, tag);
switch (ttype(L->top-1)) {
case LUA_TTABLE:
hvalue(L->top-1)->htag = tag;
break;
case LUA_TUSERDATA:
tsvalue(L->top-1)->u.d.tag = tag;
break;
default:
luaO_verror(L, "cannot change the tag of a %.20s",
luaO_typename(L->top-1));
}
}
LUA_API void lua_unref (lua_State *L, int ref) {
if (ref >= 0) {
lua_assert(ref < G(L)->nref && G(L)->refArray[ref].st < 0);
G(L)->refArray[ref].st = G(L)->refFree;
G(L)->refFree = ref;
}
}
LUA_API int lua_next (lua_State *L, int index) {
StkId t = luaA_index(L, index);
Node *n;
lua_assert(ttype(t) == LUA_TTABLE);
n = luaH_next(L, hvalue(t), luaA_index(L, -1));
if (n) {
setobj(L->top-1, key(n));
setobj(L->top, val(n));
api_incr_top(L);
return 1;
}
else { /* no more elements */
L->top -= 1; /* remove key */
return 0;
}
}
LUA_API int lua_getn (lua_State *L, int index) {
Hash *h = hvalue(luaA_index(L, index));
const TObject *value = luaH_getstr(h, luaS_newliteral(L, "n")); /* = h.n */
if (ttype(value) == LUA_TNUMBER)
return (int)nvalue(value);
else {
lua_Number max = 0;
int i = h->size;
Node *n = h->node;
while (i--) {
if (ttype(key(n)) == LUA_TNUMBER &&
ttype(val(n)) != LUA_TNIL &&
nvalue(key(n)) > max)
max = nvalue(key(n));
n++;
}
return (int)max;
}
}
LUA_API void lua_concat (lua_State *L, int n) {
StkId top = L->top;
luaV_strconc(L, n, top);
L->top = top-(n-1);
luaC_checkGC(L);
}
LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
TString *ts = luaS_newudata(L, size, NULL);
setuvalue(L->top, ts);
api_incr_top(L);
return ts->u.d.value;
}