| /* |
| ** $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 */ |
| } |
| |