Compiles with 5.2, but doesn't work.

luprex/core/cpp/luasnap.cpp

@@ -3,27 +3,6 @@
 #include <iostream>
 #include <cassert>
 
-extern "C" {
-void      *lj_alloc_create();
-void      *lj_alloc_f(void *, void *, size_t, size_t);
-lua_State *lj_state_newstate(lua_Alloc f, void *ud);
-}
-
-static void *lsnap_create() {
-    return lj_alloc_create();
-}
-static lua_State *lsnap_newstate(lua_Alloc f, void *ud) {
-    return lj_state_newstate(f, ud);
-}
-static void *lsnap_malloc(void *mptr, size_t nsize) {
-    return lj_alloc_f(mptr, 0, 0, nsize);
-}
-static void *lsnap_realloc(void *mptr, void *ptr, size_t osize, size_t nsize) {
-    return lj_alloc_f(mptr, ptr, osize, nsize);
-}
-static void *lsnap_free(void *mptr, size_t osize, void *ptr) {
-    return lj_alloc_f(mptr, ptr, osize, 0);
-}
 
 struct BlockHeader {
     BlockHeader *prev_;
@@ -50,7 +29,6 @@ class LuaSnapData {
 public:
     lua_State *state_;
     bool have_snapshot_;
-    void *lj_mstate_;
     BlockHeader sentinel_;
 
     LuaSnapData();
@@ -74,9 +52,8 @@ LuaSnapData::LuaSnapData() {
     sentinel_.size_ = 0;
     sentinel_.in_use_ = false;
     sentinel_.snapshot_ = 0;
-    lj_mstate_ = lsnap_create();
     have_snapshot_ = false;
-    state_ = lsnap_newstate(lsd_alloc_f, (void*)this);
+    state_ = lua_newstate(lsd_alloc_f, (void*)this);
 }
 
 LuaSnapData::~LuaSnapData() {
@@ -106,7 +83,7 @@ void LuaSnapData::rollback() {
         } else {
             assert(blk->in_use_);
             unlink(blk);
-            lsnap_free(lj_mstate_, blocksize(blk->size_), blk);
+            free(blk);
         }
         blk = next;
     }
@@ -137,13 +114,13 @@ void *LuaSnapData::allocf(void *ptr, size_t osize, size_t nsize) {
         assert(blk->in_use_);
         if (blk->snapshot_ == nullptr) {
             unlink(blk);
-            lsnap_free(lj_mstate_, blocksize(blk->size_), blk);
+            free(blk);
         } else {
             blk->in_use_ = false;
         }
         return nullptr;
     } else if (ptr == NULL) {
-        BlockHeader *blk = (BlockHeader*)lsnap_malloc(lj_mstate_, blocksize(nsize));
+        BlockHeader *blk = (BlockHeader*)malloc(blocksize(nsize));
         link(blk);
         blk->size_ = nsize;
         blk->in_use_ = true;
@@ -155,12 +132,12 @@ void *LuaSnapData::allocf(void *ptr, size_t osize, size_t nsize) {
         assert(blk->in_use_);
         if (blk->snapshot_ == nullptr) {
             unlink(blk);
-            blk = (BlockHeader*)lsnap_realloc(lj_mstate_, blk, blocksize(blk->size_), blocksize(nsize));
+            blk = (BlockHeader*)realloc(blk, blocksize(nsize));
             blk->size_ = nsize;
             link(blk);
             return header_to_pointer(blk);
         } else {
-            BlockHeader *nblk = (BlockHeader*)lsnap_malloc(lj_mstate_, blocksize(nsize));
+            BlockHeader *nblk = (BlockHeader*)malloc(blocksize(nsize));
             memcpy(nblk, blk, (blk->size_ < nsize) ? blk->size_ : nsize);
             blk->in_use_ = false;
             link(nblk);

luprex/core/cpp/luastack.hpp

@@ -157,6 +157,7 @@
 extern "C" {
 #include "lua.h"
 #include "lauxlib.h"
+#include "lualib.h"
 }
 
 #include <string>

luprex/core/cpp/source.cpp

@@ -70,16 +70,21 @@ static void source_install_builtins(lua_State *L) {
 
 void SourceDB::initialize(lua_State *L) {
     lua_state_ = L;
-    LuaVar key, value, skey, svalue, snapshot, ssnapshot;
+    LuaVar key, value, skey, svalue, snapshot, ssnapshot, globtab;
-    LuaStack LS(L, snapshot, key, value, skey, svalue, ssnapshot);
+    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.
-    source_install_builtins(L);
     LS.newtable(snapshot);
     LS.set(key, LuaNil);
-    while (LS.next(LuaGlobals, key, value) != 0) {
+    while (LS.next(globtab, key, value) != 0) {
         if (LS.istable(value)) {
             LS.newtable(ssnapshot);
             LS.rawset(snapshot, key, ssnapshot);
@@ -181,35 +186,41 @@ void SourceDB::update() {
 // the class tables.
 //
 static void source_clear_globals(lua_State *L) {
-    LuaVar classname, classtab, key;
+    LuaVar classname, classtab, key, globtab;
-    LuaStack LS(L, classname, classtab, key);
+    LuaStack LS(L, classname, classtab, key, globtab);
 
-    LS.rawset(LuaGlobals, "_G", LuaNil);
+    // Get the global environment.
+    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
+    
+    LS.rawset(globtab, "_G", LuaNil);
     LS.set(classname, LuaNil);
-    while (LS.next(LuaGlobals, classname, classtab) != 0) {
+    while (LS.next(globtab, classname, classtab) != 0) {
         if (LS.istable(classtab)) {
             LS.call(table_clear, classtab);
         } else {
-            LS.rawset(LuaGlobals, classname, LuaNil);
+            LS.rawset(globtab, classname, LuaNil);
         }
     }
-    LS.rawset(LuaGlobals, "_G", LuaGlobals);
+    LS.rawset(globtab, "_G", globtab);
     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;
+    LuaVar snapshot, key, value, skey, svalue, target, globtab;
-    LuaStack LS(L, snapshot, key, value, skey, svalue, target);
+    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(LuaGlobals, "_G", LuaGlobals);
+    LS.rawset(globtab, "_G", globtab);
     LS.set(key, LuaNil);
     while (LS.next(snapshot, key, value) != 0) {
         LS.checktable(value);
-        if (LS.equal(key, "_G")) {
+        if (LS.rawequal(key, "_G")) {
-            LS.set(target, LuaGlobals);
+            LS.set(target, globtab);
         } else {
             LS.makeclass(target, key);
         }
@@ -312,10 +323,11 @@ void SourceDB::rebuild() {
 
 void SourceDB::run_unittests() {
     lua_State *L = lua_state_;
-    LuaVar unittests, name, func, err;
+    LuaVar unittests, name, func, err, globtab;
-    LuaStack LS(L, unittests, name, func, err);
+    LuaStack LS(L, unittests, name, func, err, globtab);
 
-    LS.rawget(unittests, LuaGlobals, "unittests");
+    LS.rawget(globtab, LuaRegistry, LUA_RIDX_GLOBALS);
+    LS.rawget(unittests, globtab, "unittests");
 
     // Sort the unit test names.
     std::set<std::string> names;

luprex/core/cpp/world.cpp

@@ -323,7 +323,7 @@ void World::run_scheduled_threads(int64_t clk) {
         // Resume the coroutine.
         lua_State *CO = LS.ckthread(thread);
         int top = lua_gettop(CO);
-        int status = lua_resume(CO, (top > 0) ? (top - 1) : 0);
+        int status = lua_resume(CO, nullptr, (top > 0) ? (top - 1) : 0);
 
         // Three possible outcomes: finished, yielded, or errored.
         if (status == LUA_YIELD) {