Added Lua 5.5 support

* some unit tests fail/segfault/freeze, but that could be because Lua 5.5 is still in beta yet

4 files changed, 88 insertions, 25 deletions

diff --git a/src/allocator.hpp b/src/allocator.hpp
index ce65a4b..b578f12 100644
--- a/src/allocator.hpp
+++ b/src/allocator.hpp
@@ -66,7 +66,7 @@ namespace lanes {
         [[nodiscard]]
         lua_State* newState() const
         {
-            return lua_newstate(allocF, allocUD);
+            return luaW_newstate(allocF, allocUD, luaL_makeseed(nullptr));
         }
 
         [[nodiscard]]
diff --git a/src/compat.cpp b/src/compat.cpp
index 08f22ca..c833480 100644
--- a/src/compat.cpp
+++ b/src/compat.cpp
@@ -149,3 +149,41 @@ int lua_setiuservalue(lua_State* const L_, StackIndex const idx_, UserValueIndex
 }
 
 #endif // LUA_VERSION_NUM
+
+// #################################################################################################
+
+#if LUA_VERSION_NUM < 505
+
+#include <time.h>
+
+/* Size for the buffer, in bytes */
+#define BUFSEEDB (sizeof(void*) + sizeof(time_t))
+
+/* Size for the buffer in int's, rounded up */
+#define BUFSEED ((BUFSEEDB + sizeof(int) - 1) / sizeof(int))
+
+/*
+** Copy the contents of variable 'v' into the buffer pointed by 'b'.
+** (The '&b[0]' disguises 'b' to fix an absurd warning from clang.)
+*/
+#define addbuff(b, v) (memcpy(&b[0], &(v), sizeof(v)), b += sizeof(v))
+
+// Copied from Lua 5.5 lauxlib.c
+unsigned int luaL_makeseed(lua_State*)
+{
+    unsigned int buff[BUFSEED];
+    unsigned int res;
+    unsigned int i;
+    time_t t = time(nullptr);
+    char* b = (char*) buff;
+    addbuff(b, b); /* local variable's address */
+    addbuff(b, t); /* time */
+    /* fill (rare but possible) remain of the buffer with zeros */
+    memset(b, 0, sizeof(buff) - BUFSEEDB);
+    res = buff[0];
+    for (i = 1; i < BUFSEED; i++)
+        res ^= (res >> 3) + (res << 7) + buff[i];
+    return res;
+}
+
+#endif // LUA_VERSION_NUM < 505
diff --git a/src/compat.hpp b/src/compat.hpp
index 99c468c..49029df 100644
--- a/src/compat.hpp
+++ b/src/compat.hpp
@@ -21,7 +21,7 @@
 #endif // LUA_OK
 
 #ifndef LUA_ERRGCMM
-#define LUA_ERRGCMM 666 // doesn't exist in Lua 5.1 and Lua 5.4, we don't care about the actual value
+#define LUA_ERRGCMM 666 // doesn't exist in Lua 5.1 and Lua 5.4/5.5, we don't care about the actual value
 #endif // LUA_ERRGCMM
 
 
@@ -29,7 +29,7 @@
 #define LUA_LOADED_TABLE "_LOADED" // doesn't exist before Lua 5.3
 #endif // LUA_LOADED_TABLE
 
-// code is now preferring Lua 5.4 API
+// code is now preferring Lua 5.5 API
 
 // #################################################################################################
 
@@ -76,18 +76,6 @@ int luaL_getsubtable(lua_State* L_, StackIndex idx_, char const* fname_);
 
 // #################################################################################################
 
-// wrap Lua 5.3 calls under Lua 5.1 API when it is simpler that way
-#if LUA_VERSION_NUM == 503
-
-inline int luaL_optint(lua_State* L_, int n_, lua_Integer d_)
-{
-    return static_cast<int>(luaL_optinteger(L_, n_, d_));
-}
-
-#endif // LUA_VERSION_NUM == 503
-
-// #################################################################################################
-
 #if LUA_VERSION_NUM < 504
 
 void* lua_newuserdatauv(lua_State* L_, size_t sz_, UserValueCount nuvalue_);
@@ -100,15 +88,11 @@ int lua_setiuservalue(lua_State* L_, StackIndex idx_, UserValueIndex n_);
 
 // #################################################################################################
 
-// wrap Lua 5.4 calls under Lua 5.1 API when it is simpler that way
-#if LUA_VERSION_NUM == 504
+#if LUA_VERSION_NUM < 505
 
-inline int luaL_optint(lua_State* L_, StackIndex n_, lua_Integer d_)
-{
-    return static_cast<int>(luaL_optinteger(L_, n_, d_));
-}
+unsigned int luaL_makeseed(lua_State*);
 
-#endif // LUA_VERSION_NUM == 504
+#endif // LUA_VERSION_NUM < 505
 
 // #################################################################################################
 
@@ -284,6 +268,47 @@ LuaType luaW_getmodule(lua_State* L_, std::string_view const& name_);
 
 // #################################################################################################
 
+template <typename LUA_NEWSTATE>
+concept RequiresOldLuaNewState = requires(LUA_NEWSTATE f_)
+{
+    {
+        f_(nullptr, 0)
+    } -> std::same_as<lua_State*>;
+};
+
+template <RequiresOldLuaNewState LUA_NEWSTATE>
+static inline lua_State* WrapLuaNewState(LUA_NEWSTATE const lua_newstate_, lua_Alloc const allocf_, void* const ud_, [[maybe_unused]] unsigned int const seed_)
+{
+    // until Lua 5.5, lua_newstate has only 2 parameters
+    return lua_newstate_(allocf_, ud_);
+}
+
+// -------------------------------------------------------------------------------------------------
+
+template <typename LUA_NEWSTATE>
+concept RequiresNewLuaNewState = requires(LUA_NEWSTATE f_)
+{
+    {
+        f_(nullptr, nullptr, 0)
+    } -> std::same_as<lua_State*>;
+};
+
+template <RequiresNewLuaNewState LUA_NEWSTATE>
+static inline lua_State* WrapLuaNewState(LUA_NEWSTATE const lua_newstate_, lua_Alloc const allocf_, void* const ud_, unsigned int const seed_)
+{
+    // starting with Lua 5.5, lua_newstate has 3 parameters
+    return lua_newstate_(allocf_, ud_, seed_);
+}
+
+// -------------------------------------------------------------------------------------------------
+
+static inline lua_State* luaW_newstate(lua_Alloc const allocf_, void* const ud_, unsigned int const seed_)
+{
+    return WrapLuaNewState(lua_newstate, allocf_, ud_, seed_);
+}
+
+// #################################################################################################
+
 template<typename ENUM>
 requires std::is_enum_v<ENUM>
 [[nodiscard]]
@@ -364,7 +389,7 @@ template <typename LUA_RAWGET>
 concept RequiresOldLuaRawget = requires(LUA_RAWGET f_) { { f_(nullptr, 0) } -> std::same_as<void>; };
 
 template <RequiresOldLuaRawget LUA_RAWGET>
-static inline LuaType WrapLuaRawget(LUA_RAWGET lua_rawget_, lua_State* const L_, StackIndex const idx_)
+static inline LuaType WrapLuaRawget(LUA_RAWGET const lua_rawget_, lua_State* const L_, StackIndex const idx_)
 {
     // until Lua 5.3, lua_rawget -> void
     lua_rawget_(L_, idx_);
@@ -377,7 +402,7 @@ template <typename LUA_RAWGET>
 concept RequiresNewLuaRawget = requires(LUA_RAWGET f_) { { f_(nullptr, 0) } -> std::same_as<int>; };
 
 template <RequiresNewLuaRawget LUA_RAWGET>
-static inline LuaType WrapLuaRawget(LUA_RAWGET lua_rawget_, lua_State* const L_, StackIndex const idx_)
+static inline LuaType WrapLuaRawget(LUA_RAWGET const lua_rawget_, lua_State* const L_, StackIndex const idx_)
 {
     // starting with Lua 5.3, lua_rawget -> int (the type of the extracted value)
     return static_cast<LuaType>(lua_rawget_(L_, idx_));
diff --git a/src/universe.cpp b/src/universe.cpp
index 044c841..4db036b 100644
--- a/src/universe.cpp
+++ b/src/universe.cpp
@@ -447,7 +447,7 @@ int Universe::UniverseGC(lua_State* const L_)
     if (!lua_isnil(L_, -1)) {
         lua_pushboolean(L_, _allLanesTerminated);                                                  // L_: U finalizer bool
         // no protection. Lua rules for errors in finalizers apply normally:
-        // Lua 5.4: error is propagated in the warn system
+        // Lua 5.4+: error is propagated in the warn system
         // older: error is swallowed
         lua_call(L_, 1, 1);                                                                        // L_: U msg?
         // phew, no error in finalizer, since we reached that point