Completed port to eris lua 5.2

luprex/core/cpp/luastack.cpp

@@ -137,6 +137,11 @@ int LuaStack::next(LuaSlot tab, LuaSlot key, LuaSlot value) const {
     return ret;
 }
 
+void LuaStack::getglobaltable(LuaSlot target) const {
+    lua_pushglobaltable(L_);
+    lua_replace(L_, target);
+}
+
 void LuaStack::newtable(LuaSlot target) const {
     lua_newtable(L_);
     lua_replace(L_, target);
@@ -149,6 +154,7 @@ lua_State *LuaStack::newthread(LuaSlot target) const {
 }
 
 void LuaStack::makeclass(LuaSlot classtab, LuaSlot classname) const {
+    lua_checkstack(L_, 20);
     LuaVar globtab;
     LuaStack LS(L_, globtab);
 

luprex/core/cpp/luastack.hpp

@@ -390,8 +390,8 @@ public:
 
     void newtable(LuaSlot target) const;
     lua_State *newthread(LuaSlot target) const;
-
     void makesubtable(LuaSlot sub, LuaSlot tab, const char *name) const;
+    void getglobaltable(LuaSlot gltab) const;
 
     int next(LuaSlot tab, LuaSlot key, LuaSlot value) const;
 

luprex/core/cpp/source.cpp

@@ -50,54 +50,40 @@ LuaDefine(source_maketangible, "f") {
     return LS.result();
 }
 
-// Load the builtins.
 
-static void load_builtin(lua_State *L, const char *name, lua_CFunction func) {
-    lua_pushcfunction(L, func);
-    lua_pushstring(L, name);
-    lua_call(L, 1, 0);
+// the 'luaopen' function creates a new table.
+//
+// We don't want to create new tables during reload, so we call luaopen,
+// then we copy the contents of the new table into the existing 'makeclass'
+// table.
+//
+static void load_builtin_class(lua_State *L, const char *name, lua_CFunction func) {
+    LuaVar sourcetab, classtab, key, value;
+    LuaStack LS(L, sourcetab, classtab, key, value);
+    LS.makeclass(classtab, name);
+    func(L);
+    lua_replace(L, sourcetab.index());
+    LS.set(key, LuaNil);
+    while (LS.next(sourcetab, key, value) != 0) {
+        LS.rawset(classtab, key, value);
+    }
 }
 
 static void source_install_builtins(lua_State *L) {
-    LuaStack LS(L);
-    load_builtin(L, "base", luaopen_base);
-    load_builtin(L, "table", luaopen_table);
-    load_builtin(L, "string", luaopen_string);
-    load_builtin(L, "math", luaopen_math);
-    load_builtin(L, "bit", luaopen_math);
-    load_builtin(L, "debug", luaopen_debug);
-}
+    LuaVar nullstring, stringclass;
+    LuaStack LS(L, nullstring, stringclass);
+    luaopen_base(L);
+    load_builtin_class(L, "table", luaopen_table);
+    load_builtin_class(L, "string", luaopen_string);
+    load_builtin_class(L, "math", luaopen_math);
+    load_builtin_class(L, "debug", luaopen_debug);
 
-void SourceDB::initialize(lua_State *L) {
-    lua_state_ = L;
-    LuaVar key, value, skey, svalue, snapshot, ssnapshot, globtab;
-    LuaStack LS(L, snapshot, key, value, skey, svalue, ssnapshot, globtab);
-
-    // Install the builtins.
-    source_install_builtins(L);
-    
-    // Get the global environment.
-    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
-
-    // Note: the global environment contains _G.  This routine
-    // perceives this as a subtable, so it backs up the top level
-    // as well.
-    LS.newtable(snapshot);
-    LS.set(key, LuaNil);
-    while (LS.next(globtab, key, value) != 0) {
-        if (LS.istable(value)) {
-            LS.newtable(ssnapshot);
-            LS.rawset(snapshot, key, ssnapshot);
-            LS.set(skey, LuaNil);
-            while (LS.next(value, skey, svalue) != 0) {
-                if (LS.isfunction(svalue) || LS.isstring(svalue) || LS.isnumber(svalue)) {
-                    LS.rawset(ssnapshot, skey, svalue);
-                }
-            }
-        }
-    }
-    LS.rawset(LuaRegistry, "source_snapshot_builtins", snapshot);
-    LS.result();
+    // Set the metatable for strings.
+    // Normally, this would be done by luaopen_string, but we're
+    // messing with the tables so we have to redo it.
+    LS.makeclass(stringclass, "string");
+    LS.set(nullstring, "");
+    LS.setmetatable(nullstring, stringclass);
 }
 
 static int source_updatefile(lua_State *L) {
@@ -189,9 +175,7 @@ static void source_clear_globals(lua_State *L) {
     LuaVar classname, classtab, key, globtab;
     LuaStack LS(L, classname, classtab, key, globtab);
 
-    // Get the global environment.
-    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
-    
+    LS.getglobaltable(globtab);
     LS.rawset(globtab, "_G", LuaNil);
     LS.set(classname, LuaNil);
     while (LS.next(globtab, classname, classtab) != 0) {
@@ -205,32 +189,6 @@ static void source_clear_globals(lua_State *L) {
     LS.result();
 }
 
-// Restore the lua builtins from the backup snapshot.
-//
-static void source_restore_builtins(lua_State *L) {
-    LuaVar snapshot, key, value, skey, svalue, target, globtab;
-    LuaStack LS(L, snapshot, key, value, skey, svalue, target, globtab);
-
-    // Get the global environment table.
-    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
-
-    LS.rawget(snapshot, LuaRegistry, "source_snapshot_builtins");
-    LS.rawset(globtab, "_G", globtab);
-    LS.set(key, LuaNil);
-    while (LS.next(snapshot, key, value) != 0) {
-        LS.checktable(value);
-        if (LS.rawequal(key, "_G")) {
-            LS.set(target, globtab);
-        } else {
-            LS.makeclass(target, key);
-        }
-        LS.set(skey, LuaNil);
-        while (LS.next(value, skey, svalue) != 0) {
-            LS.rawset(target, skey, svalue);
-        }
-    }
-    LS.result();
-}
 
 // Load all the 'LuaDefine' C functions into the lua state.
 //
@@ -312,7 +270,7 @@ void SourceDB::rebuild() {
     LuaVar errs;
     LuaStack LS(L, errs);
     source_clear_globals(L);
-    source_restore_builtins(L);
+    source_install_builtins(L);
     source_load_cfunctions(L);
     source_load_lfunctions(L);
     lua_replace(L, errs.index());
@@ -326,7 +284,7 @@ void SourceDB::run_unittests() {
     LuaVar unittests, name, func, err, globtab;
     LuaStack LS(L, unittests, name, func, err, globtab);
 
-    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
+    LS.getglobaltable(globtab);
     LS.rawget(unittests, globtab, "unittests");
 
     // Sort the unit test names.

luprex/core/cpp/source.hpp

@@ -127,14 +127,8 @@ private:
     lua_State *lua_state_;
 
 public:
-    // Initialize
-    //
-    // This must be called while the lua state is still pristine.
-    // This will install the builtin operators into the lua state
-    // and will snapshot those builtins to the registry.
-    //
-    void initialize(lua_State *L);
-
+    void init(lua_State *L) { lua_state_ = L; }
+    
     // Update
     //
     // Read all the lua source files from disk and store them in the

luprex/core/cpp/world.cpp

@@ -30,7 +30,7 @@ World::World() {
     LS.rawset(LuaRegistry, "tangibles", LuaNewTable);
 
     // Initialize the SourceDB
-    source_db_.initialize(state());
+    source_db_.init(state());
     source_db_.rebuild();
 
     LS.result();