Rewrite code, but keeping the exact same semantic and behaviourHEADmain

- assert that the generated `siphash.o` code is identical to the
  original code, available at `tests/assert-identical.sh`;
- remove unneeded `#define`s;
- rewrite code with the correct indentation, spacing and formatting;
- use C99 constructs over C89 (for loop variable declarations inside
  the parentheses);
- fix the public API.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/impl.h b/src/impl.h
new file mode 100644
index 0000000..166ccae
--- /dev/null
+++ b/src/impl.h
@@ -0,0 +1,8 @@
+int
+siphash_impl(
+	const void *const restrict in,
+	const size_t               inlen,
+	const void *const restrict key,
+	u8 out[16U],
+	const size_t               outlen
+);