Merge pull request #485 from MihailRis/crc32

crc32

res/scripts/stdmin.lua

@@ -26,6 +26,38 @@ function __vc_Canvas_set_data(self, data)
     self:_set_data(tostring(_ffi.cast("uintptr_t", canvas_ffi_buffer)))
 end
 
+_ffi.cdef([[
+    unsigned long crc32(unsigned long crc, const char *buf, unsigned len);
+]])
+
+local zlib
+if _ffi.os == "Windows" then
+    zlib = _ffi.load("zlib1")
+elseif _ffi.os == "OSX" then
+    zlib = _ffi.load("z")
+elseif _ffi.os == "Linux" then
+    zlib = _ffi.load("libz.so.1")
+else
+    error("platform does not support zlib " .. _ffi.os)
+end
+
+function crc32(bytes, chksum)
+    local chksum = chksum or 0
+
+    local length = #bytes
+    if type(bytes) == "string" then
+        return zlib.crc32(chksum, bytes, length)
+    elseif type(bytes) == "table" then
+        local buffer = _ffi.new(
+            string.format("char[%s]", length)
+        )
+        for i=1, length do
+            buffer[i - 1] = bytes[i]
+        end
+        return zlib.crc32(chksum, buffer, length)
+    end
+end
+
 -- Check if given table is an array
 function is_array(x)
     if #x > 0 then

src/logic/scripting/lua/libs/libfile.cpp

@@ -30,7 +30,7 @@ static int l_resolve(lua::State* L) {
 static int l_read(lua::State* L) {
     io::path path = lua::require_string(L, 1);
     if (io::is_regular_file(path)) {
-        return lua::pushstring(L, io::read_string(path));
+        return lua::pushlstring(L, io::read_string(path));
     }
     throw std::runtime_error(
         "file does not exists " + util::quote(path.string())

src/logic/scripting/lua/lua_util.hpp

@@ -184,6 +184,11 @@ namespace lua {
         return 1;
     }
 
+    inline int pushlstring(lua::State* L, std::string_view view) {
+        lua_pushlstring(L, reinterpret_cast<const char*>(view.data()), view.size());
+        return 1;
+    }
+
     template <typename... Args>
     inline int pushfstring(lua_State* L, const char* fmt, Args... args) {
         lua_pushfstring(L, fmt, args...);