lfunc.c
上传用户:yisoukefu
上传日期:2020-08-09
资源大小:39506k
文件大小:4k
- /*
- ** $Id: lfunc.c,v 2.12 2005/12/22 16:19:56 roberto Exp $
- ** Auxiliary functions to manipulate prototypes and closures
- ** See Copyright Notice in lua.h
- */
- #include <stddef.h>
- #define lfunc_c
- #define LUA_CORE
- #include "lua.h"
- #include "lfunc.h"
- #include "lgc.h"
- #include "lmem.h"
- #include "lobject.h"
- #include "lstate.h"
- Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
- Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
- luaC_link(L, obj2gco(c), LUA_TFUNCTION);
- c->c.isC = 1;
- c->c.env = e;
- c->c.nupvalues = cast_byte(nelems);
- return c;
- }
- Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e) {
- Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
- luaC_link(L, obj2gco(c), LUA_TFUNCTION);
- c->l.isC = 0;
- c->l.env = e;
- c->l.nupvalues = cast_byte(nelems);
- while (nelems--) c->l.upvals[nelems] = NULL;
- return c;
- }
- UpVal *luaF_newupval (lua_State *L) {
- UpVal *uv = luaM_new(L, UpVal);
- luaC_link(L, obj2gco(uv), LUA_TUPVAL);
- uv->v = &uv->u.value;
- setnilvalue(uv->v);
- return uv;
- }
- UpVal *luaF_findupval (lua_State *L, StkId level) {
- global_State *g = G(L);
- GCObject **pp = &L->openupval;
- UpVal *p;
- UpVal *uv;
- while ((p = ngcotouv(*pp)) != NULL && p->v >= level) {
- lua_assert(p->v != &p->u.value);
- if (p->v == level) { /* found a corresponding upvalue? */
- if (isdead(g, obj2gco(p))) /* is it dead? */
- changewhite(obj2gco(p)); /* ressurect it */
- return p;
- }
- pp = &p->next;
- }
- uv = luaM_new(L, UpVal); /* not found: create a new one */
- uv->tt = LUA_TUPVAL;
- uv->marked = luaC_white(g);
- uv->v = level; /* current value lives in the stack */
- uv->next = *pp; /* chain it in the proper position */
- *pp = obj2gco(uv);
- uv->u.l.prev = &g->uvhead; /* double link it in `uvhead' list */
- uv->u.l.next = g->uvhead.u.l.next;
- uv->u.l.next->u.l.prev = uv;
- g->uvhead.u.l.next = uv;
- lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
- return uv;
- }
- static void unlinkupval (UpVal *uv) {
- lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
- uv->u.l.next->u.l.prev = uv->u.l.prev; /* remove from `uvhead' list */
- uv->u.l.prev->u.l.next = uv->u.l.next;
- }
- void luaF_freeupval (lua_State *L, UpVal *uv) {
- if (uv->v != &uv->u.value) /* is it open? */
- unlinkupval(uv); /* remove from open list */
- luaM_free(L, uv); /* free upvalue */
- }
- void luaF_close (lua_State *L, StkId level) {
- UpVal *uv;
- global_State *g = G(L);
- while ((uv = ngcotouv(L->openupval)) != NULL && uv->v >= level) {
- GCObject *o = obj2gco(uv);
- lua_assert(!isblack(o) && uv->v != &uv->u.value);
- L->openupval = uv->next; /* remove from `open' list */
- if (isdead(g, o))
- luaF_freeupval(L, uv); /* free upvalue */
- else {
- unlinkupval(uv);
- setobj(L, &uv->u.value, uv->v);
- uv->v = &uv->u.value; /* now current value lives here */
- luaC_linkupval(L, uv); /* link upvalue into `gcroot' list */
- }
- }
- }
- Proto *luaF_newproto (lua_State *L) {
- Proto *f = luaM_new(L, Proto);
- luaC_link(L, obj2gco(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->sizeupvalues = 0;
- f->nups = 0;
- f->upvalues = NULL;
- f->numparams = 0;
- f->is_vararg = 0;
- f->maxstacksize = 0;
- f->lineinfo = NULL;
- f->sizelocvars = 0;
- f->locvars = NULL;
- f->linedefined = 0;
- f->lastlinedefined = 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, TValue);
- luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
- luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
- luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
- luaM_free(L, f);
- }
- void luaF_freeclosure (lua_State *L, Closure *c) {
- int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
- sizeLclosure(c->l.nupvalues);
- luaM_freemem(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 */
- }