Migrate to Lua 5.4

1 files changed, 30 insertions, 0 deletions

diff --git a/data/core/bit.lua b/data/core/bit.lua
new file mode 100644
index 00000000..f357d5fd
--- /dev/null
+++ b/data/core/bit.lua
@@ -0,0 +1,30 @@
+local bit = {}
+
+local LUA_NBITS = 32
+local ALLONES = (~(((~0) << (LUA_NBITS - 1)) << 1))
+
+local function trim(x)
+	return (x & ALLONES)
+end
+
+local function mask(n)
+	return (~((ALLONES << 1) << ((n) - 1)))
+end
+
+function bit.extract(n, field, width)
+	local r = trim(field)
+	local f = width
+	r = (r >> f) & mask(width)
+	return r
+end
+
+function bit.replace(n, v, field, width)
+	local r = trim(v);
+	local v = trim(field);
+	local f = width
+	local m = mask(width);
+	r = (r & ~(m << f)) | ((v & m) << f);
+	return r
+end
+
+return bit
\ No newline at end of file