invariant tests over tables performed externally, through a built-in

function (when DEBUG is ion).

lbuiltin.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lbuiltin.c,v 1.67 1999/10/14 19:13:31 roberto Exp roberto $
+** $Id: lbuiltin.c,v 1.68 1999/10/19 13:33:22 roberto Exp roberto $
 ** Built-in functions
 ** See Copyright Notice in lua.h
 */
@@ -68,7 +68,7 @@ static real getnarg (const Hash *a) {
 }
 
 
-static Hash *gethash (int arg) {
+static Hash *gettable (int arg) {
   return avalue(luaA_Address(luaL_tablearg(arg)));
 }
 
@@ -285,7 +285,7 @@ static void luaB_dofile (void) {
 
 static void luaB_call (void) {
   lua_Object f = luaL_nonnullarg(1);
-  const Hash *arg = gethash(2);
+  const Hash *arg = gettable(2);
   const char *options = luaL_opt_string(3, "");
   lua_Object err = lua_getparam(4);
   int narg = (int)getnarg(arg);
@@ -335,7 +335,7 @@ static void luaB_nextvar (void) {
 
 
 static void luaB_next (void) {
-  const Hash *a = gethash(1);
+  const Hash *a = gettable(1);
   const TObject *k = luaA_Address(luaL_nonnullarg(2));
   int i;  /* will get first element after `i' */
   if (ttype(k) == LUA_T_NIL)
@@ -406,7 +406,7 @@ static void luaB_assert (void) {
 
 
 static void luaB_foreachi (void) {
-  const Hash *t = gethash(1);
+  const Hash *t = gettable(1);
   int i;
   int n = (int)getnarg(t);
   TObject f;
@@ -428,7 +428,7 @@ static void luaB_foreachi (void) {
 
 
 static void luaB_foreach (void) {
-  const Hash *a = gethash(1);
+  const Hash *a = gettable(1);
   int i;
   TObject f;  /* see comment in 'foreachi' */
   f = *luaA_Address(luaL_functionarg(2));
@@ -472,12 +472,12 @@ static void luaB_foreachvar (void) {
 
 
 static void luaB_getn (void) {
-  lua_pushnumber(getnarg(gethash(1)));
+  lua_pushnumber(getnarg(gettable(1)));
 }
 
 
 static void luaB_tinsert (void) {
-  Hash *a = gethash(1);
+  Hash *a = gettable(1);
   lua_Object v = lua_getparam(3);
   int n = (int)getnarg(a);
   int pos;
@@ -495,7 +495,7 @@ static void luaB_tinsert (void) {
 
 
 static void luaB_tremove (void) {
-  Hash *a = gethash(1);
+  Hash *a = gettable(1);
   int n = (int)getnarg(a);
   int pos = luaL_opt_int(2, n);
   if (n <= 0) return;  /* table is "empty" */
@@ -583,7 +583,7 @@ static void auxsort (Hash *a, int l, int u, lua_Object f) {
 
 static void luaB_sort (void) {
   lua_Object t = lua_getparam(1);
-  Hash *a = gethash(1);
+  Hash *a = gettable(1);
   int n = (int)getnarg(a);
   lua_Object func = lua_getparam(2);
   luaL_arg_check(func == LUA_NOOBJECT || lua_isfunction(func), 2,
@@ -616,8 +616,14 @@ static void mem_query (void) {
 
 static void hash_query (void) {
   const TObject *o = luaA_Address(luaL_nonnullarg(1));
+  if (lua_getparam(2) == LUA_NOOBJECT) {
     luaL_arg_check(ttype(o) == LUA_T_STRING, 1, "string expected");
     lua_pushnumber(tsvalue(o)->hash);
+  }
+  else {
+    const Hash *t = avalue(luaA_Address(luaL_tablearg(2)));
+    lua_pushnumber(luaH_mainposition(t, o) - t->node);
+  }
 }
 
 
@@ -631,7 +637,8 @@ static void table_query (void) {
   else if (i < t->size) {
     luaA_pushobject(&t->node[i].key);
     luaA_pushobject(&t->node[i].val);
-    lua_pushnumber(t->node[i].next == NULL ? 0 : t->node[i].next - t->node);
+    if (t->node[i].next)
+      lua_pushnumber(t->node[i].next - t->node);
   }
 }
 

ltable.c

@@ -1,5 +1,5 @@
 /*
-** $Id: ltable.c,v 1.26 1999/10/14 19:13:31 roberto Exp roberto $
+** $Id: ltable.c,v 1.27 1999/10/19 13:33:22 roberto Exp roberto $
 ** Lua tables (hash)
 ** See Copyright Notice in lua.h
 */
@@ -38,7 +38,7 @@
 ** returns the `main' position of an element in a table (that is, the index
 ** of its hash value)
 */
-static Node *luaH_mainposition (const Hash *t, const TObject *key) {
+Node *luaH_mainposition (const Hash *t, const TObject *key) {
   unsigned long h;
   switch (ttype(key)) {
     case LUA_T_NUMBER:
@@ -90,7 +90,7 @@ static Node *hashnodecreate (int nhash) {
   Node *v = luaM_newvector(nhash, Node);
   int i;
   for (i=0; i<nhash; i++) {
-    ttype(key(&v[i])) = ttype(val(&v[i])) = LUA_T_NIL;
+    ttype(&v[i].key) = ttype(&v[i].val) = LUA_T_NIL;
     v[i].next = NULL;
   }
   return v;
@@ -129,48 +129,13 @@ static int newsize (const Hash *t) {
   int realuse = 0;
   int i;
   for (i=0; i<size; i++) {
-    if (ttype(val(v+i)) != LUA_T_NIL)
+    if (ttype(&v[i].val) != LUA_T_NIL)
       realuse++;
   }
   return luaO_redimension(realuse*2);
 }
 
 
-#ifdef DEBUG
-/* check invariant of a table */
-static int listfind (const Node *m, const Node *n) {
-  do {
-    if (m==n) return 1;
-    m = m->next;
-  } while (m);
-  return 0;
-}
-
-static int check_invariant (const Hash *t, int filled) {
-  Node *n;
-  for (n=t->node; n<t->firstfree; n++) {
-    TObject *key = &n->key;
-    LUA_ASSERT(ttype(key) == LUA_T_NIL || n == luaH_mainposition(t, key),
-      "all elements before firstfree are empty or in their main positions");
-  }
-  if (!filled)
-    LUA_ASSERT(ttype(&(n++)->key) == LUA_T_NIL, "firstfree must be empty");
-  else
-    LUA_ASSERT(n == t->node, "table cannot have empty places");
-  for (; n<t->node+t->size; n++) {
-    TObject *key = &n->key;
-    Node *mp = luaH_mainposition(t, key);
-    LUA_ASSERT(ttype(key) != LUA_T_NIL,
-      "cannot exist empty elements after firstfree");
-    LUA_ASSERT(n == mp || luaH_mainposition(t, &mp->key) == mp,
-      "either an element or its colliding element is in its main position");
-    LUA_ASSERT(listfind(mp,n), "element is in its main position list");
-  }
-  return 1;
-}
-#endif
-
-
 /*
 ** the rehash is done in two stages: first, we insert only the elements whose
 ** main position is free, to avoid needless collisions. In the second stage,
@@ -180,7 +145,6 @@ static void rehash (Hash *t) {
   int oldsize = t->size;
   Node *nold = t->node;
   int i;
-  LUA_ASSERT(check_invariant(t, 1), "invalid table");
   L->nblocks -= gcsize(oldsize);
   setnodevector(t, newsize(t));  /* create new array of nodes */
   /* first loop; set only elements that can go in their main positions */
@@ -216,7 +180,6 @@ static void rehash (Hash *t) {
       } while (ttype(&t->firstfree->key) != LUA_T_NIL);
     }
   }
-  LUA_ASSERT(check_invariant(t, 0), "invalid table");
   luaM_free(nold);  /* free old array */
 }
 

ltable.h

@@ -1,5 +1,5 @@
 /*
-** $Id: ltable.h,v 1.13 1999/10/04 17:51:04 roberto Exp roberto $
+** $Id: ltable.h,v 1.14 1999/10/14 19:13:31 roberto Exp roberto $
 ** Lua tables (hash)
 ** See Copyright Notice in lua.h
 */
@@ -23,7 +23,10 @@ void luaH_set (Hash *t, const TObject *key, const TObject *val);
 int luaH_pos (const Hash *t, const TObject *r);
 void luaH_setint (Hash *t, int key, const TObject *val);
 const TObject *luaH_getint (const Hash *t, int key);
-unsigned long luaH_hash (const TObject *key);  /* exported only for debugging */
+unsigned long luaH_hash (const TObject *key);
+
+/* exported only for debugging */
+Node *luaH_mainposition (const Hash *t, const TObject *key);
 
 
 #endif