Add API for creating custom version 8 UUIDs

core/encoding/uuid/stamping.odin

@@ -0,0 +1,89 @@
+package uuid
+
+import "base:runtime"
+
+/*
+Stamp a 128-bit integer as being a valid version 8 UUID.
+
+Per the specification, all version 8 UUIDs are either for experimental or
+vendor-specific purposes. This procedure allows for converting arbitrary data
+into custom UUIDs.
+
+Inputs:
+- integer: Any integer type.
+
+Returns:
+- result: A valid version 8 UUID.
+*/
+stamp_v8_int :: proc(#any_int integer: u128) -> (result: Identifier) {
+	result = transmute(Identifier)cast(u128be)integer
+
+	result[VERSION_BYTE_INDEX] &= 0x0F
+	result[VERSION_BYTE_INDEX] |= 0x80
+
+	result[VARIANT_BYTE_INDEX] &= 0x3F
+	result[VARIANT_BYTE_INDEX] |= 0x80
+
+	return
+}
+
+/*
+Stamp an array of 16 bytes as being a valid version 8 UUID.
+
+Per the specification, all version 8 UUIDs are either for experimental or
+vendor-specific purposes. This procedure allows for converting arbitrary data
+into custom UUIDs.
+
+Inputs:
+- array: An array of 16 bytes.
+
+Returns:
+- result: A valid version 8 UUID.
+*/
+stamp_v8_array :: proc(array: [16]u8) -> (result: Identifier) {
+	result = transmute(Identifier)array
+
+	result[VERSION_BYTE_INDEX] &= 0x0F
+	result[VERSION_BYTE_INDEX] |= 0x80
+
+	result[VARIANT_BYTE_INDEX] &= 0x3F
+	result[VARIANT_BYTE_INDEX] |= 0x80
+
+	return
+}
+
+/*
+Stamp a slice of bytes as being a valid version 8 UUID.
+
+If the slice is less than 16 bytes long, the data available will be used.
+If it is longer than 16 bytes, only the first 16 will be used.
+
+This procedure does not modify the underlying slice.
+
+Per the specification, all version 8 UUIDs are either for experimental or
+vendor-specific purposes. This procedure allows for converting arbitrary data
+into custom UUIDs.
+
+Inputs:
+- slice: A slice of bytes.
+
+Returns:
+- result: A valid version 8 UUID.
+*/
+stamp_v8_slice :: proc(slice: []u8) -> (result: Identifier) {
+	runtime.mem_copy_non_overlapping(&result, &slice[0], min(16, len(slice)))
+
+	result[VERSION_BYTE_INDEX] &= 0x0F
+	result[VERSION_BYTE_INDEX] |= 0x80
+
+	result[VARIANT_BYTE_INDEX] &= 0x3F
+	result[VARIANT_BYTE_INDEX] |= 0x80
+
+	return
+}
+
+stamp_v8 :: proc {
+	stamp_v8_int,
+	stamp_v8_array,
+	stamp_v8_slice,
+}