lua/lapi.c

781 lines
16 KiB
C

/*
** $Id: lapi.c,v 1.146 2001/06/15 20:36:57 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
#include <string.h>
#define LUA_PRIVATE
#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 l_char lua_ident[] = l_s("$Lua: ") l_s(LUA_VERSION) l_s(" ")
l_s(LUA_COPYRIGHT) l_s(" $\n") l_s("$Authors: ") l_s(LUA_AUTHORS) l_s(" $");
#ifndef api_check
#define api_check(L, o) /* nothing */
#endif
#define api_checknelems(L, n) api_check(L, (n) <= (L->top - L->ci->base))
#define api_incr_top(L) incr_top
TObject *luaA_index (lua_State *L, int index) {
if (index > 0) {
api_check(L, index <= L->top - L->ci->base);
return L->ci->base+index-1;
}
else {
api_check(L, index != 0 && -index <= L->top - L->ci->base);
return L->top+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 {
api_check(L, index != 0 && -index <= L->top - L->ci->base);
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->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);
luaD_adjusttop(L, 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_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 l_char *lua_tag2name (lua_State *L, int tag) {
const l_char *s;
lua_lock(L);
s = (tag == LUA_TNONE) ? l_s("no value") : basictypename(G(L), tag);
lua_unlock(L);
return s;
}
LUA_API const l_char *lua_xtypename (lua_State *L, int index) {
StkId o;
const l_char *type;
lua_lock(L);
o = luaA_indexAcceptable(L, index);
type = (o == NULL) ? l_s("no value") : luaT_typename(G(L), o);
lua_unlock(L);
return type;
}
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;
TObject *o = luaA_indexAcceptable(L, index);
return (o != NULL && (ttype(o) == LUA_TNUMBER || luaV_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_tag (lua_State *L, int index) {
StkId o;
int i;
lua_lock(L); /* other thread could be changing the tag */
o = luaA_indexAcceptable(L, index);
i = (o == NULL) ? LUA_NOTAG : luaT_tag(o);
lua_unlock(L);
return i;
}
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 &&
(ttype(o) == LUA_TNUMBER || (o = luaV_tonumber(o, &n)) != NULL))
return nvalue(o);
else
return 0;
}
LUA_API const l_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 l_char *s;
lua_lock(L); /* `luaV_tostring' may create a new string */
s = (luaV_tostring(L, o) == 0) ? 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) == 0) ? 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)->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 : uvalue(o)->uv.value;
}
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 l_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 l_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) {
lua_lock(L);
api_checknelems(L, n);
luaV_Cclosure(L, fn, n);
lua_unlock(L);
}
/*
** get functions (Lua -> stack)
*/
LUA_API void lua_getglobal (lua_State *L, const l_char *name) {
lua_lock(L);
luaV_getglobal(L, luaS_new(L, name), L->top);
api_incr_top(L);
lua_unlock(L);
}
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_getglobals (lua_State *L) {
lua_lock(L);
sethvalue(L->top, L->gt);
api_incr_top(L);
lua_unlock(L);
}
LUA_API int lua_getref (lua_State *L, int ref) {
int status;
lua_lock(L);
if (ref == LUA_REFNIL) {
setnilvalue(L->top);
status = 1;
}
else {
setobj(L->top, luaH_getnum(G(L)->weakregistry, ref));
status = (ttype(L->top) != LUA_TNIL);
}
if (status)
api_incr_top(L);
lua_unlock(L);
return status;
}
LUA_API void lua_newtable (lua_State *L) {
lua_lock(L);
sethvalue(L->top, luaH_new(L, 0));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_getregistry (lua_State *L) {
lua_lock(L);
sethvalue(L->top, G(L)->registry);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_getweakregistry (lua_State *L) {
lua_lock(L);
sethvalue(L->top, G(L)->weakregistry);
api_incr_top(L);
lua_unlock(L);
}
/*
** set functions (stack -> Lua)
*/
LUA_API void lua_setglobal (lua_State *L, const l_char *name) {
lua_lock(L);
api_checknelems(L, 1);
luaV_setglobal(L, luaS_new(L, name), L->top - 1);
L->top--; /* remove element from the top */
lua_unlock(L);
}
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);
setobj(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);
setobj(luaH_setnum(L, hvalue(o), n), (L->top-1));
L->top--;
lua_unlock(L);
}
LUA_API void lua_setglobals (lua_State *L) {
StkId newtable;
lua_lock(L);
api_checknelems(L, 1);
newtable = --L->top;
api_check(L, ttype(newtable) == LUA_TTABLE);
L->gt = hvalue(newtable);
lua_unlock(L);
}
LUA_API int lua_ref (lua_State *L, int lock) {
int ref;
if (lua_isnil(L, -1)) {
lua_pop(L, 1);
ref = LUA_REFNIL;
}
else {
lua_getweakregistry(L);
ref = lua_getn(L, -1) + 1;
lua_pushvalue(L, -2);
lua_rawseti(L, -2, ref);
if (lock) {
lua_getregistry(L);
lua_pushvalue(L, -3);
lua_rawseti(L, -2, ref);
lua_pop(L, 1); /* remove registry */
}
lua_pushliteral(L, "n");
lua_pushnumber(L, ref);
lua_settable(L, -3);
lua_pop(L, 2);
}
return ref;
}
/*
** `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);
if (nresults != LUA_MULTRET)
luaD_adjusttop(L, func + nresults);
lua_unlock(L);
}
LUA_API int lua_dofile (lua_State *L, const l_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 l_char *buff, size_t size,
const l_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 l_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) ((int)((x)>>10))
#define GCunscale(x) ((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 int lua_newxtype (lua_State *L, const l_char *name, int basictype) {
int tag;
lua_lock(L);
if (basictype != LUA_TNONE &&
basictype != LUA_TTABLE &&
basictype != LUA_TUSERDATA)
luaO_verror(L, l_s("invalid basic type (%d) for new type"), basictype);
tag = luaT_newtag(L, name, basictype);
if (tag == LUA_TNONE)
luaO_verror(L, l_s("type name '%.30s' already exists"), name);
lua_unlock(L);
return tag;
}
LUA_API int lua_name2tag (lua_State *L, const l_char *name) {
int tag;
const TObject *v;
lua_lock(L);
v = luaH_getstr(G(L)->type2tag, luaS_new(L, name));
if (ttype(v) == LUA_TNIL)
tag = LUA_TNONE;
else {
lua_assert(ttype(v) == LUA_TNUMBER);
tag = (int)nvalue(v);
}
lua_unlock(L);
return tag;
}
LUA_API void lua_settag (lua_State *L, int tag) {
int basictype;
lua_lock(L);
api_checknelems(L, 1);
if (tag < 0 || tag >= G(L)->ntag)
luaO_verror(L, l_s("%d is not a valid tag"), tag);
basictype = G(L)->TMtable[tag].basictype;
if (basictype != LUA_TNONE && basictype != ttype(L->top-1))
luaO_verror(L, l_s("tag %d can only be used for type '%.20s'"), tag,
basictypename(G(L), basictype));
switch (ttype(L->top-1)) {
case LUA_TTABLE:
hvalue(L->top-1)->htag = tag;
break;
case LUA_TUSERDATA:
uvalue(L->top-1)->uv.tag = tag;
break;
default:
luaO_verror(L, l_s("cannot change the tag of a %.20s"),
luaT_typename(G(L), L->top-1));
}
lua_unlock(L);
}
LUA_API void lua_error (lua_State *L, const l_char *s) {
lua_lock(L);
luaD_error(L, s);
lua_unlock(L);
}
LUA_API void lua_unref (lua_State *L, int ref) {
if (ref >= 0) {
lua_getregistry(L);
lua_pushnil(L);
lua_rawseti(L, -2, ref);
lua_getweakregistry(L);
lua_pushnil(L);
lua_rawseti(L, -2, ref);
lua_pop(L, 2); /* remove both registries */
}
}
LUA_API int lua_next (lua_State *L, int index) {
StkId t;
Node *n;
int more;
lua_lock(L);
t = luaA_index(L, index);
api_check(L, 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);
more = 1;
}
else { /* no more elements */
L->top -= 1; /* remove key */
more = 0;
}
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, l_s("n"))); /* = t.n */
if (ttype(value) == LUA_TNUMBER)
n = (int)nvalue(value);
else {
lua_Number max = 0;
int i = hvalue(t)->size;
Node *nd = hvalue(t)->node;
while (i--) {
if (ttype(key(nd)) == LUA_TNUMBER &&
ttype(val(nd)) != LUA_TNIL &&
nvalue(key(nd)) > max)
max = nvalue(key(nd));
nd++;
}
n = (int)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->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);
}
static Udata *pushnewudata (lua_State *L, size_t size) {
Udata *u = luaS_newudata(L, size);
setuvalue(L->top, u);
api_incr_top(L);
return uvalue(L->top-1);
}
LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
Udata *u;
void *p;
lua_lock(L);
u = pushnewudata(L, size);
p = u->uv.value;
lua_unlock(L);
return p;
}
LUA_API void lua_newuserdatabox (lua_State *L, void *p) {
Udata *u;
lua_lock(L);
u = pushnewudata(L, 0);
u->uv.value = p;
lua_unlock(L);
}
LUA_API int lua_getweakmode (lua_State *L, int index) {
StkId t;
int mode;
lua_lock(L);
t = luaA_index(L, index);
api_check(L, ttype(t) == LUA_TTABLE);
mode = hvalue(t)->weakmode;
lua_unlock(L);
return mode;
}
LUA_API void lua_setweakmode (lua_State *L, int mode) {
lua_lock(L);
api_check(L, ttype(L->top-1) == LUA_TTABLE);
hvalue(L->top-1)->weakmode = mode;
lua_unlock(L);
}