/* BEGIN CSTYLED */ /* ** $Id: lfunc.c,v 2.30.1.1 2013/04/12 18:48:47 roberto Exp $ ** Auxiliary functions to manipulate prototypes and closures ** See Copyright Notice in lua.h */ #define lfunc_c #define LUA_CORE #include #include "lfunc.h" #include "lgc.h" #include "lmem.h" #include "lobject.h" #include "lstate.h" Closure *luaF_newCclosure (lua_State *L, int n) { Closure *c = &luaC_newobj(L, LUA_TCCL, sizeCclosure(n), NULL, 0)->cl; c->c.nupvalues = cast_byte(n); return c; } Closure *luaF_newLclosure (lua_State *L, int n) { Closure *c = &luaC_newobj(L, LUA_TLCL, sizeLclosure(n), NULL, 0)->cl; c->l.p = NULL; c->l.nupvalues = cast_byte(n); while (n--) c->l.upvals[n] = NULL; return c; } UpVal *luaF_newupval (lua_State *L) { UpVal *uv = &luaC_newobj(L, LUA_TUPVAL, sizeof(UpVal), NULL, 0)->uv; 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 = gco2uv(*pp))->v >= level) { GCObject *o = obj2gco(p); lua_assert(p->v != &p->u.value); lua_assert(!isold(o) || isold(obj2gco(L))); if (p->v == level) { /* found a corresponding upvalue? */ if (isdead(g, o)) /* is it dead? */ changewhite(o); /* resurrect it */ return p; } pp = &p->next; } /* not found: create a new one */ uv = &luaC_newobj(L, LUA_TUPVAL, sizeof(UpVal), pp, 0)->uv; uv->v = level; /* current value lives in the stack */ 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 = gco2uv(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); /* remove upvalue from 'uvhead' list */ setobj(L, &uv->u.value, uv->v); /* move value to upvalue slot */ uv->v = &uv->u.value; /* now current value lives here */ gch(o)->next = g->allgc; /* link upvalue into 'allgc' list */ g->allgc = o; luaC_checkupvalcolor(g, uv); } } } Proto *luaF_newproto (lua_State *L) { Proto *f = &luaC_newobj(L, LUA_TPROTO, sizeof(Proto), NULL, 0)->p; f->k = NULL; f->sizek = 0; f->p = NULL; f->sizep = 0; f->code = NULL; f->cache = NULL; f->sizecode = 0; f->lineinfo = NULL; f->sizelineinfo = 0; f->upvalues = NULL; f->sizeupvalues = 0; f->numparams = 0; f->is_vararg = 0; f->maxstacksize = 0; f->locvars = NULL; f->sizelocvars = 0; 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); luaM_freearray(L, f->p, f->sizep); luaM_freearray(L, f->k, f->sizek); luaM_freearray(L, f->lineinfo, f->sizelineinfo); luaM_freearray(L, f->locvars, f->sizelocvars); luaM_freearray(L, f->upvalues, f->sizeupvalues); luaM_free(L, f); } /* ** 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; isizelocvars && 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 */ } /* END CSTYLED */