lua/lfunc.c
2002-12-04 15:38:31 -02:00

133 lines
3.3 KiB
C

/*
** $Id: lfunc.c,v 1.63 2002/11/14 16:15:53 roberto Exp roberto $
** Auxiliary functions to manipulate prototypes and closures
** See Copyright Notice in lua.h
*/
#include <stdlib.h>
#define lfunc_c
#include "lua.h"
#include "lfunc.h"
#include "lgc.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#define sizeCclosure(n) (cast(int, sizeof(CClosure)) + \
cast(int, sizeof(TObject)*((n)-1)))
#define sizeLclosure(n) (cast(int, sizeof(LClosure)) + \
cast(int, sizeof(TObject *)*((n)-1)))
Closure *luaF_newCclosure (lua_State *L, int nelems) {
Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
luaC_link(L, valtogco(c), LUA_TFUNCTION);
c->c.isC = 1;
c->c.nupvalues = cast(lu_byte, nelems);
return c;
}
Closure *luaF_newLclosure (lua_State *L, int nelems, TObject *gt) {
Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
luaC_link(L, valtogco(c), LUA_TFUNCTION);
c->l.isC = 0;
c->l.g = *gt;
c->l.nupvalues = cast(lu_byte, nelems);
return c;
}
UpVal *luaF_findupval (lua_State *L, StkId level) {
GCObject **pp = &L->openupval;
UpVal *p;
UpVal *v;
while ((p = ngcotouv(*pp)) != NULL && p->v >= level) {
if (p->v == level) return p;
pp = &p->next;
}
v = luaM_new(L, UpVal); /* not found: create a new one */
v->tt = LUA_TUPVAL;
v->marked = 1; /* open upvalues should not be collected */
v->v = level; /* current value lives in the stack */
v->next = *pp; /* chain it in the proper position */
*pp = valtogco(v);
return v;
}
void luaF_close (lua_State *L, StkId level) {
UpVal *p;
while ((p = ngcotouv(L->openupval)) != NULL && p->v >= level) {
setobj(&p->value, p->v); /* save current value (write barrier) */
p->v = &p->value; /* now current value lives here */
L->openupval = p->next; /* remove from `open' list */
luaC_link(L, valtogco(p), LUA_TUPVAL);
}
}
Proto *luaF_newproto (lua_State *L) {
Proto *f = luaM_new(L, Proto);
luaC_link(L, valtogco(f), LUA_TPROTO);
f->k = NULL;
f->sizek = 0;
f->p = NULL;
f->sizep = 0;
f->code = NULL;
f->sizecode = 0;
f->sizelineinfo = 0;
f->nupvalues = 0;
f->numparams = 0;
f->is_vararg = 0;
f->maxstacksize = 0;
f->lineinfo = NULL;
f->sizelocvars = 0;
f->locvars = NULL;
f->lineDefined = 0;
f->source = NULL;
return f;
}
void luaF_freeproto (lua_State *L, Proto *f) {
luaM_freearray(L, f->code, f->sizecode, Instruction);
luaM_freearray(L, f->p, f->sizep, Proto *);
luaM_freearray(L, f->k, f->sizek, TObject);
luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
luaM_freelem(L, f);
}
void luaF_freeclosure (lua_State *L, Closure *c) {
int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
sizeLclosure(c->l.nupvalues);
luaM_free(L, c, size);
}
/*
** Look for n-th local variable at line `line' in function `func'.
** Returns NULL if not found.
*/
const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
int i;
for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
if (pc < f->locvars[i].endpc) { /* is variable active? */
local_number--;
if (local_number == 0)
return getstr(f->locvars[i].varname);
}
}
return NULL; /* not found */
}