Make the endian test more C++-like

1 files changed, 35 insertions, 0 deletions

diff --git a/common/albit.h b/common/albit.h
new file mode 100644
index 00000000..225c0b89
--- /dev/null
+++ b/common/albit.h
@@ -0,0 +1,35 @@
+#ifndef AL_BIT_H
+#define AL_BIT_H
+
+namespace al {
+
+#ifdef __BYTE_ORDER__
+enum class endian {
+    little = __ORDER_LITTLE_ENDIAN__,
+    big = __ORDER_BIG_ENDIAN__,
+    native = __BYTE_ORDER__
+};
+
+#else
+
+/* This doesn't support mixed-endian. */
+namespace detail_ {
+constexpr inline bool EndianTest() noexcept
+{
+    static_assert(sizeof(char) < sizeof(int), "char is too big");
+
+    constexpr int test_val{1};
+    return static_cast<const char&>(test_val);
+}
+} // namespace detail_
+
+enum class endian {
+    little = 0,
+    big = 1,
+    native = detail_::EndianTest() ? little : big
+};
+#endif
+
+} // namespace al
+
+#endif /* AL_BIT_H */