/* move `dead' udata that need finalization to list `tmudata' */ size_t luaC_separateudata (lua_State *L, int all) { global_State *g = G(L); size_t deadmem = 0; GCObject **p = &g->mainthread->next; GCObject *curr; while ((curr = *p) != NULL) { if (!(iswhite(curr) || all) || isfinalized(gco2u(curr))) p = &curr->gch.next; /* don't bother with them */ else if (fasttm(L, gco2u(curr)->metatable, TM_GC) == NULL) { markfinalized(gco2u(curr)); /* don't need finalization */ p = &curr->gch.next; } else { /* must call its gc method */ deadmem += sizeudata(gco2u(curr)); markfinalized(gco2u(curr)); *p = curr->gch.next; /* link `curr' at the end of `tmudata' list */ if (g->tmudata == NULL) /* list is empty? */ g->tmudata = curr->gch.next = curr; /* creates a circular list */ else { curr->gch.next = g->tmudata->gch.next; g->tmudata->gch.next = curr; g->tmudata = curr; } } } return deadmem; }
/* ** mark an object. Userdata, strings, and closed upvalues are visited ** and turned black here. Other objects are marked gray and added ** to appropriate list to be visited (and turned black) later. (Open ** upvalues are already linked in 'headuv' list.) */ static void reallymarkobject (global_State *g, GCObject *o) { lu_mem size; white2gray(o); switch (gch(o)->tt) { case LUA_TSHRSTR: case LUA_TLNGSTR: { size = sizestring(gco2ts(o)); break; /* nothing else to mark; make it black */ } case LUA_TUSERDATA: { Table *mt = gco2u(o)->metatable; markobject(g, mt); markobject(g, gco2u(o)->env); size = sizeudata(gco2u(o)); break; } case LUA_TUPVAL: { UpVal *uv = gco2uv(o); markvalue(g, uv->v); if (uv->v != &uv->u.value) /* open? */ return; /* open upvalues remain gray */ size = sizeof(UpVal); break; } case LUA_TLCL: { gco2lcl(o)->gclist = g->gray; g->gray = o; return; } case LUA_TCCL: { gco2ccl(o)->gclist = g->gray; g->gray = o; return; } case LUA_TTABLE: { linktable(gco2t(o), &g->gray); return; } case LUA_TTHREAD: { gco2th(o)->gclist = g->gray; g->gray = o; return; } case LUA_TPROTO: { gco2p(o)->gclist = g->gray; g->gray = o; return; } default: lua_assert(0); return; } gray2black(o); g->GCmemtrav += size; }
void reallymarkobject (global_State *g, GCObject *o) { #else static void reallymarkobject (global_State *g, GCObject *o) { #endif /* LUAPLUS_EXTENSIONS */ lua_assert(iswhite(o) && !isdead(g, o)); white2gray(o); switch (o->gch.tt) { case LUA_TSTRING: { return; } #if LUA_WIDESTRING case LUA_TWSTRING: { return; } #endif /* LUA_WIDESTRING */ case LUA_TUSERDATA: { Table *mt = gco2u(o)->metatable; gray2black(o); /* udata are never gray */ if (mt) markobject(g, mt); markobject(g, gco2u(o)->env); return; } case LUA_TUPVAL: { UpVal *uv = gco2uv(o); markvalue(g, uv->v); if (uv->v == &uv->u.value) /* closed? */ gray2black(o); /* open upvalues are never black */ return; } case LUA_TFUNCTION: { gco2cl(o)->c.gclist = g->gray; g->gray = o; break; } case LUA_TTABLE: { gco2h(o)->gclist = g->gray; g->gray = o; break; } case LUA_TTHREAD: { gco2th(o)->gclist = g->gray; g->gray = o; break; } case LUA_TPROTO: { gco2p(o)->gclist = g->gray; g->gray = o; break; } default: lua_assert(0); } }
/* ** mark an object. Userdata, strings, and closed upvalues are visited ** and turned black here. Other objects are marked gray and added ** to appropriate list to be visited (and turned black) later. (Open ** upvalues are already linked in 'headuv' list.) */ static void reallymarkobject (global_State *g, GCObject *o) { reentry: white2gray(o); switch (o->tt) { case LUA_TSHRSTR: { gray2black(o); g->GCmemtrav += sizelstring(gco2ts(o)->shrlen); break; } case LUA_TLNGSTR: { gray2black(o); g->GCmemtrav += sizelstring(gco2ts(o)->u.lnglen); break; } case LUA_TUSERDATA: { TValue uvalue; markobjectN(g, gco2u(o)->metatable); /* mark its metatable */ gray2black(o); g->GCmemtrav += sizeudata(gco2u(o)); getuservalue(g->mainthread, gco2u(o), &uvalue); if (valiswhite(&uvalue)) { /* markvalue(g, &uvalue); */ o = gcvalue(&uvalue); goto reentry; } break; } case LUA_TLCL: { linkgclist(gco2lcl(o), g->gray); break; } case LUA_TCCL: { linkgclist(gco2ccl(o), g->gray); break; } case LUA_TTABLE: { linkgclist(gco2t(o), g->gray); break; } case LUA_TTHREAD: { linkgclist(gco2th(o), g->gray); break; } case LUA_TPROTO: { linkgclist(gco2p(o), g->gray); break; } default: lua_assert(0); break; } }
static void freeobj (lua_State *L, GCObject *o) { switch (o->tt) { case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break; case LUA_TLCL: { freeLclosure(L, gco2lcl(o)); break; } case LUA_TCCL: { luaM_freemem(L, o, sizeCclosure(gco2ccl(o)->nupvalues)); break; } case LUA_TTABLE: luaH_free(L, gco2t(o)); break; case LUA_TTHREAD: luaE_freethread(L, gco2th(o)); break; case LUA_TUSERDATA: luaM_freemem(L, o, sizeudata(gco2u(o))); break; case LUA_TSHRSTR: luaS_remove(L, gco2ts(o)); /* remove it from hash table */ luaM_freemem(L, o, sizelstring(gco2ts(o)->shrlen)); break; case LUA_TLNGSTR: { luaM_freemem(L, o, sizelstring(gco2ts(o)->u.lnglen)); break; } default: lua_assert(0); } }
static void freeobj (lua_State *L, GCObject *o) { switch (gch(o)->tt) { case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break; case LUA_TLCL: { luaM_freemem(L, o, sizeLclosure(gco2lcl(o)->nupvalues)); break; } case LUA_TCCL: { luaM_freemem(L, o, sizeCclosure(gco2ccl(o)->nupvalues)); break; } case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break; case LUA_TTABLE: luaH_free(L, gco2t(o)); break; case LUA_TTHREAD: luaE_freethread(L, gco2th(o)); break; case LUA_TUSERDATA: luaM_freemem(L, o, sizeudata(gco2u(o))); break; case LUA_TSHRSTR: G(L)->strt.nuse--; /* go through */ case LUA_TLNGSTR: { luaM_freemem(L, o, sizestring(gco2ts(o))); break; } default: lua_assert(0); } }
static void freeobj(lua_State *L, GCObject *o) { switch (o->gch.tt) { case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break; case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break; case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break; case LUA_TTABLE: luaH_free(L, gco2h(o)); break; case LUA_TTHREAD: { lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread); luaE_freethread(L, gco2th(o)); break; } case LUA_TSTRING: { G(L)->strt.nuse--; luaM_freemem(L, o, sizestring(gco2ts(o))); break; } case LUA_TUSERDATA: { luaM_freemem(L, o, sizeudata(gco2u(o))); break; } default: lua_assert(0); } }
static void reallymarkobject (global_State *g, GCObject *o) { lua_assert(iswhite(o) && !isdead(g, o)); white2gray(o);// 先将白变灰 switch (o->gch.tt) {// 根据不同类型进行不同的操作 case LUA_TSTRING: { return; // 不通过gc管理 } case LUA_TUSERDATA: { Table *mt = gco2u(o)->metatable; gray2black(o); /* udata are never gray */ if (mt) markobject(g, mt); markobject(g, gco2u(o)->env); return; } case LUA_TUPVAL: { UpVal *uv = gco2uv(o); markvalue(g, uv->v); if (uv->v == &uv->u.value) /* closed? */ gray2black(o); /* open upvalues are never black */ return; } case LUA_TFUNCTION: { gco2cl(o)->c.gclist = g->gray; g->gray = o; break; } case LUA_TTABLE: { gco2h(o)->gclist = g->gray; g->gray = o; break; } case LUA_TTHREAD: { gco2th(o)->gclist = g->gray; g->gray = o; break; } case LUA_TPROTO: { gco2p(o)->gclist = g->gray; g->gray = o; break; } default: lua_assert(0); } }
/* ** mark an object. Userdata and closed upvalues are visited and turned ** black here. Strings remain gray (it is the same as making them ** black). Other objects are marked gray and added to appropriate list ** to be visited (and turned black) later. (Open upvalues are already ** linked in 'headuv' list.) */ static void reallymarkobject (global_State *g, GCObject *o) { lua_assert(iswhite(o) && !isdead(g, o)); white2gray(o); switch (gch(o)->tt) { case LUA_TSTRING: { return; /* for strings, gray is as good as black */ } case LUA_TUSERDATA: { Table *mt = gco2u(o)->metatable; markobject(g, mt); markobject(g, gco2u(o)->env); gray2black(o); /* all pointers marked */ return; } case LUA_TUPVAL: { UpVal *uv = gco2uv(o); markvalue(g, uv->v); if (uv->v == &uv->u.value) /* closed? (open upvalues remain gray) */ gray2black(o); /* make it black */ return; } case LUA_TFUNCTION: { gco2cl(o)->c.gclist = g->gray; g->gray = o; break; } case LUA_TTABLE: { linktable(gco2t(o), &g->gray); break; } case LUA_TTHREAD: { gco2th(o)->gclist = g->gray; g->gray = o; break; } case LUA_TPROTO: { gco2p(o)->gclist = g->gray; g->gray = o; break; } default: lua_assert(0); } }
static void freeobj (lua_State *L, GCObject *o) { global_State *g = G(L); lua_assert(is_robj(o)); switch (o->gch.tt) { case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break; case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break; case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break; case LUA_TTABLE: luaH_free(L, gco2h(o)); break; case LUA_TTHREAD: { lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread); luaE_freethread(L, gco2th(o)); break; } case LUA_TSTRING: { G(L)->strt.nuse--; luaM_freemem(L, o, sizestring(gco2ts(o))); break; } case LUA_TUSERDATA: { const Udata *udata = rawgco2u(o); const TValue *tm = fasttm(L, udata->uv.metatable, TM_GC); if (tm != NULL) { lu_byte oldah = L->allowhook; lu_mem oldt = g->GCthreshold; L->allowhook = 0; /* stop debug hooks during GC tag method */ g->GCthreshold = 2*g->totalbytes; /* avoid GC steps */ setobj2s(L, L->top, tm); setuvalue(L, L->top+1, udata); L->top += 2; luaD_call(L, L->top - 2, 0); L->allowhook = oldah; /* restore hooks */ g->GCthreshold = oldt; /* restore threshold */ } luaM_freemem(L, o, sizeudata(gco2u(o))); break; } default: lua_assert(0); } }
static void cleartable (lua_State *L, GCObject *l) { #else static void cleartable (GCObject *l) { #endif /* LUA_REFCOUNT */ while (l) { Table *h = gco2h(l); int i = h->sizearray; lua_assert(testbit(h->marked, VALUEWEAKBIT) || testbit(h->marked, KEYWEAKBIT)); if (testbit(h->marked, VALUEWEAKBIT)) { while (i--) { TValue *o = &h->array[i]; #if LUA_REFCOUNT if (iscleared(o, 0)) { /* value was collected? */ if (iscollectable(o)) o->value.gc->gch.ref--; setnilvalue2n(l, o); /* remove value */ } #else if (iscleared(o, 0)) /* value was collected? */ setnilvalue(o); /* remove value */ #endif /* LUA_REFCOUNT */ } } i = sizenode(h); while (i--) { Node *n = gnode(h, i); if (!ttisnil(gval(n)) && /* non-empty entry? */ (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) { #if LUA_REFCOUNT if (iscollectable(gval(n))) gval(n)->value.gc->gch.ref--; setnilvalue2n(L, gval(n)); /* remove value ... */ #else setnilvalue(gval(n)); /* remove value ... */ #endif /* LUA_REFCOUNT */ removeentry(n); /* remove entry from table */ } } l = h->gclist; } } static void freeobj (lua_State *L, GCObject *o) { switch (o->gch.tt) { case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break; case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break; case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break; case LUA_TTABLE: luaH_free(L, gco2h(o)); break; case LUA_TTHREAD: { lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread); luaE_freethread(L, gco2th(o)); break; } case LUA_TSTRING: { G(L)->strt.nuse--; luaM_freemem(L, o, sizestring(gco2ts(o))); break; } #if LUA_WIDESTRING case LUA_TWSTRING: { G(L)->strt.nuse--; luaM_freemem(L, o, sizestring(gco2ts(o))); break; } #endif /* LUA_WIDESTRING */ case LUA_TUSERDATA: { luaM_freemem(L, o, sizeudata(gco2u(o))); break; } default: lua_assert(0); } } #define sweepwholelist(L,p) sweeplist(L,p,MAX_LUMEM) static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count) { GCObject *curr; global_State *g = G(L); int deadmask = otherwhite(g); while ((curr = *p) != NULL && count-- > 0) { if (curr->gch.tt == LUA_TTHREAD) /* sweep open upvalues of each thread */ sweepwholelist(L, &gco2th(curr)->openupval); if ((curr->gch.marked ^ WHITEBITS) & deadmask) { /* not dead? */ lua_assert(!isdead(g, curr) || testbit(curr->gch.marked, FIXEDBIT)); makewhite(g, curr); /* make it white (for next cycle) */ p = &curr->gch.next; } else { /* must erase `curr' */ lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT)); #if LUA_REFCOUNT if (curr->gch.prev) curr->gch.prev->gch.next = curr->gch.next; if (curr->gch.next) curr->gch.next->gch.prev = (GCObject*)p; #endif /* LUA_REFCOUNT */ *p = curr->gch.next; if (curr == g->rootgc) /* is the first element of the list? */ g->rootgc = curr->gch.next; /* adjust first */ freeobj(L, curr); } } return p; }