/*** $Id: lfunc.c,v 2.12.1.2 2007/12/28 14:58:43 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 (*pp != NULL && (p = ngcotouv(*pp))->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 (L->openupval != NULL && (uv = ngcotouv(L->openupval))->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 */}
