1 files changed, 44 insertions, 6 deletions

diff --git a/src/compat.cpp b/src/compat.cpp
index 7e90142..c833480 100644
--- a/src/compat.cpp
+++ b/src/compat.cpp
@@ -5,10 +5,10 @@
 
 // #################################################################################################
 
-UserValueCount luaG_getalluservalues(lua_State* const L_, StackIndex const idx_)
+UserValueCount luaW_getalluservalues(lua_State* const L_, StackIndex const idx_)
 {
     STACK_CHECK_START_REL(L_, 0);
-    StackIndex const _idx{ luaG_absindex(L_, idx_) };
+    StackIndex const _idx{ luaW_absindex(L_, idx_) };
     UserValueIndex _nuv{ 0 };
     do {
         // we don't know how many uservalues we are going to extract, there might be a lot...
@@ -24,15 +24,15 @@ UserValueCount luaG_getalluservalues(lua_State* const L_, StackIndex const idx_)
 // #################################################################################################
 
 // a small helper to obtain a module's table from the registry instead of relying on the presence of _G["<name>"]
-LuaType luaG_getmodule(lua_State* const L_, std::string_view const& name_)
+LuaType luaW_getmodule(lua_State* const L_, std::string_view const& name_)
 {
     STACK_CHECK_START_REL(L_, 0);
-    LuaType _type{ luaG_getfield(L_, kIdxRegistry, LUA_LOADED_TABLE) };                            // L_: _R._LOADED|nil
+    LuaType _type{ luaW_getfield(L_, kIdxRegistry, LUA_LOADED_TABLE) };                            // L_: _R._LOADED|nil
     if (_type != LuaType::TABLE) {                                                                 // L_: _R._LOADED|nil
         STACK_CHECK(L_, 1);
         return _type;
     }
-    _type = luaG_getfield(L_, kIdxTop, name_);                                                     // L_: _R._LOADED {module}|nil
+    _type = luaW_getfield(L_, kIdxTop, name_);                                                     // L_: _R._LOADED {module}|nil
     lua_remove(L_, -2);                                                                            // L_: {module}|nil
     STACK_CHECK(L_, 1);
     return _type;
@@ -52,7 +52,7 @@ int luaL_getsubtable(lua_State* const L_, StackIndex const idx_, char const* fna
         return 1; /* table already there */
     } else {
         lua_pop(L_, 1); /* remove previous result */
-        StackIndex const _absidx{ luaG_absindex(L_, idx_) };
+        StackIndex const _absidx{ luaW_absindex(L_, idx_) };
         lua_newtable(L_);
         lua_pushvalue(L_, -1); /* copy to be left at top */
         lua_setfield(L_, _absidx, fname_); /* assign new table to field */
@@ -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