1 files changed, 47 insertions, 70 deletions

diff --git a/src/lua/lfunc.c b/src/lua/lfunc.c
index c4360f0..13e44d4 100644
--- a/src/lua/lfunc.c
+++ b/src/lua/lfunc.c
@@ -100,80 +100,57 @@ UpVal *luaF_findupval (lua_State *L, StkId level) {
 }
 
 
-static void callclose (lua_State *L, void *ud) {
-  UNUSED(ud);
-  luaD_callnoyield(L, L->top - 3, 0);
-}
-
-
 /*
-** Prepare closing method plus its arguments for object 'obj' with
-** error message 'err'. (This function assumes EXTRA_STACK.)
+** Call closing method for object 'obj' with error message 'err'. The
+** boolean 'yy' controls whether the call is yieldable.
+** (This function assumes EXTRA_STACK.)
 */
-static int prepclosingmethod (lua_State *L, TValue *obj, TValue *err) {
+static void callclosemethod (lua_State *L, TValue *obj, TValue *err, int yy) {
   StkId top = L->top;
   const TValue *tm = luaT_gettmbyobj(L, obj, TM_CLOSE);
-  if (ttisnil(tm))  /* no metamethod? */
-    return 0;  /* nothing to call */
   setobj2s(L, top, tm);  /* will call metamethod... */
   setobj2s(L, top + 1, obj);  /* with 'self' as the 1st argument */
   setobj2s(L, top + 2, err);  /* and error msg. as 2nd argument */
   L->top = top + 3;  /* add function and arguments */
-  return 1;
+  if (yy)
+    luaD_call(L, top, 0);
+  else
+    luaD_callnoyield(L, top, 0);
 }
 
 
 /*
-** Raise an error with message 'msg', inserting the name of the
-** local variable at position 'level' in the stack.
+** Check whether 'obj' has a close metamethod and raise an error
+** if not.
 */
-static void varerror (lua_State *L, StkId level, const char *msg) {
-  int idx = cast_int(level - L->ci->func);
-  const char *vname = luaG_findlocal(L, L->ci, idx, NULL);
-  if (vname == NULL) vname = "?";
-  luaG_runerror(L, msg, vname);
+static void checkclosemth (lua_State *L, StkId level, const TValue *obj) {
+  const TValue *tm = luaT_gettmbyobj(L, obj, TM_CLOSE);
+  if (ttisnil(tm)) {  /* no metamethod? */
+    int idx = cast_int(level - L->ci->func);  /* variable index */
+    const char *vname = luaG_findlocal(L, L->ci, idx, NULL);
+    if (vname == NULL) vname = "?";
+    luaG_runerror(L, "variable '%s' got a non-closable value", vname);
+  }
 }
 
 
 /*
-** Prepare and call a closing method. If status is OK, code is still
-** inside the original protected call, and so any error will be handled
-** there. Otherwise, a previous error already activated the original
-** protected call, and so the call to the closing method must be
-** protected here. (A status == CLOSEPROTECT behaves like a previous
-** error, to also run the closing method in protected mode).
-** If status is OK, the call to the closing method will be pushed
-** at the top of the stack. Otherwise, values are pushed after
-** the 'level' of the upvalue being closed, as everything after
-** that won't be used again.
+** Prepare and call a closing method.
+** If status is CLOSEKTOP, the call to the closing method will be pushed
+** at the top of the stack. Otherwise, values can be pushed right after
+** the 'level' of the upvalue being closed, as everything after that
+** won't be used again.
 */
-static int callclosemth (lua_State *L, StkId level, int status) {
+static void prepcallclosemth (lua_State *L, StkId level, int status, int yy) {
   TValue *uv = s2v(level);  /* value being closed */
-  if (likely(status == LUA_OK)) {
-    if (prepclosingmethod(L, uv, &G(L)->nilvalue))  /* something to call? */
-      callclose(L, NULL);  /* call closing method */
-    else if (!l_isfalse(uv))  /* non-closable non-false value? */
-      varerror(L, level, "attempt to close non-closable variable '%s'");
+  TValue *errobj;
+  if (status == CLOSEKTOP)
+    errobj = &G(L)->nilvalue;  /* error object is nil */
+  else {  /* 'luaD_seterrorobj' will set top to level + 2 */
+    errobj = s2v(level + 1);  /* error object goes after 'uv' */
+    luaD_seterrorobj(L, status, level + 1);  /* set error object */
   }
-  else {  /* must close the object in protected mode */
-    ptrdiff_t oldtop;
-    level++;  /* space for error message */
-    oldtop = savestack(L, level + 1);  /* top will be after that */
-    luaD_seterrorobj(L, status, level);  /* set error message */
-    if (prepclosingmethod(L, uv, s2v(level))) {  /* something to call? */
-      int newstatus = luaD_pcall(L, callclose, NULL, oldtop, 0);
-      if (newstatus != LUA_OK && status == CLOSEPROTECT)  /* first error? */
-        status = newstatus;  /* this will be the new error */
-      else {
-        if (newstatus != LUA_OK)  /* suppressed error? */
-          luaE_warnerror(L, "__close metamethod");
-        /* leave original error (or nil) on top */
-        L->top = restorestack(L, oldtop);
-      }
-    }
-    /* else no metamethod; ignore this case and keep original error */
-  }
-  return status;
+  callclosemethod(L, uv, errobj, yy);
 }
 
 
@@ -196,16 +173,12 @@ void luaF_newtbcupval (lua_State *L, StkId level) {
   lua_assert(L->openupval == NULL || uplevel(L->openupval) < level);
   if (!l_isfalse(obj)) {  /* false doesn't need to be closed */
     int status;
-    const TValue *tm = luaT_gettmbyobj(L, obj, TM_CLOSE);
-    if (ttisnil(tm))  /* no metamethod? */
-      varerror(L, level, "variable '%s' got a non-closable value");
+    checkclosemth(L, level, obj);
     status = luaD_rawrunprotected(L, trynewtbcupval, level);
     if (unlikely(status != LUA_OK)) {  /* memory error creating upvalue? */
       lua_assert(status == LUA_ERRMEM);
       luaD_seterrorobj(L, LUA_ERRMEM, level + 1);  /* save error message */
-      /* next call must succeed, as object is closable */
-      prepclosingmethod(L, s2v(level), s2v(level + 1));
-      callclose(L, NULL);  /* call closing method */
+      callclosemethod(L, s2v(level), s2v(level + 1), 0);
       luaD_throw(L, LUA_ERRMEM);  /* throw memory error */
     }
   }
@@ -220,26 +193,30 @@ void luaF_unlinkupval (UpVal *uv) {
 }
 
 
-int luaF_close (lua_State *L, StkId level, int status) {
+/*
+** Close all upvalues up to the given stack level. A 'status' equal
+** to NOCLOSINGMETH closes upvalues without running any __close
+** metamethods.
+*/
+void luaF_close (lua_State *L, StkId level, int status, int yy) {
   UpVal *uv;
-  while ((uv = L->openupval) != NULL && uplevel(uv) >= level) {
+  StkId upl;  /* stack index pointed by 'uv' */
+  while ((uv = L->openupval) != NULL && (upl = uplevel(uv)) >= level) {
     TValue *slot = &uv->u.value;  /* new position for value */
     lua_assert(uplevel(uv) < L->top);
-    if (uv->tbc && status != NOCLOSINGMETH) {
-      /* must run closing method, which may change the stack */
-      ptrdiff_t levelrel = savestack(L, level);
-      status = callclosemth(L, uplevel(uv), status);
-      level = restorestack(L, levelrel);
-    }
-    luaF_unlinkupval(uv);
+    luaF_unlinkupval(uv);  /* remove upvalue from 'openupval' list */
     setobj(L, slot, uv->v);  /* move value to upvalue slot */
     uv->v = slot;  /* now current value lives here */
     if (!iswhite(uv)) {  /* neither white nor dead? */
       nw2black(uv);  /* closed upvalues cannot be gray */
       luaC_barrier(L, uv, slot);
     }
+    if (uv->tbc && status != NOCLOSINGMETH) {
+      ptrdiff_t levelrel = savestack(L, level);
+      prepcallclosemth(L, upl, status, yy);  /* may change the stack */
+      level = restorestack(L, levelrel);
+    }
   }
-  return status;
 }