m + add libsimple_random_bytes

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 39 insertions, 0 deletions

diff --git a/random_bytes.c b/random_bytes.c
new file mode 100644
index 0000000..cd7416f
--- /dev/null
+++ b/random_bytes.c
@@ -0,0 +1,39 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+void *
+libsimple_random_bytes(uintmax_t (*rng)(size_t bits, void *user), void *user, void *buffer, size_t bytes)
+{
+	char *buf = buffer;
+	uintmax_t rnd;
+
+	while (bytes >= sizeof(uintmax_t)) {
+		*(uintmax_t *)buf = (*rng)(sizeof(uintmax_t) * 8U, user);
+		bytes -= sizeof(uintmax_t);
+		buf = &buf[sizeof(uintmax_t)];
+	}
+
+	if (bytes) {
+		rnd = (*rng)(bytes * 8U, user);
+		while (bytes) {
+			*buf++ = (char)(rnd & 255U);
+			rnd >>= 8;
+		}
+	}
+
+	return buf;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	return 0;
+}
+
+#endif