erster Commit

1 files changed, 47 insertions, 0 deletions

diff --git a/random.h b/random.h
new file mode 100644
index 0000000..9094d5b
--- /dev/null
+++ b/random.h
@@ -0,0 +1,47 @@
+#ifndef ITS1_RANDOM_H_INCLUDED
+#define ITS1_RANDOM_H_INCLUDED
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct random_ctx {
+        unsigned char (*get_byte)(struct random_ctx *ctx);
+};
+
+static unsigned char
+random_get_byte(struct random_ctx *ctx)
+{
+        return ctx->get_byte(ctx);
+}
+
+static unsigned short
+random_get_word(struct random_ctx *ctx)
+{
+        return (ctx->get_byte(ctx) << 8)
+                 |  ctx->get_byte(ctx)
+                 ;
+}
+
+static unsigned long
+random_get_dword(struct random_ctx *ctx)
+{
+        return (ctx->get_byte(ctx) << 24)
+                 | (ctx->get_byte(ctx) << 16)
+                 | (ctx->get_byte(ctx) <<  8)
+                 |  ctx->get_byte(ctx)
+                 ;
+}
+
+static unsigned long
+random_get_dword_range(struct random_ctx *ctx, unsigned long l, unsigned long u)
+{
+        return l + random_get_dword(ctx) % (u - l + 1);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  /* ITS1_RANDOM_H_INCLUDED */
+