From: Andrey Rys <rys@lynxlynx.ru>
Date: Wed, 10 Apr 2019 05:27:30 +0000 (+0700)
Subject: tfprng: expose range formula in form of macros to build custom range generators.
X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=8f5731f876403829977834c82c7afbecc484a02d;p=tfcrypt.git

tfprng: expose range formula in form of macros to build custom range generators.
---

diff --git a/VERSION b/VERSION
index 6f4247a..f64f5d8 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-26
+27
diff --git a/tfprng.c b/tfprng.c
index d4370f3..4db2418 100644
--- a/tfprng.c
+++ b/tfprng.c
@@ -85,7 +85,7 @@ TF_UNIT_TYPE tf_prng_range_r(void *sdata, TF_UNIT_TYPE s, TF_UNIT_TYPE d)
 {
 	TF_UNIT_TYPE c = tf_prng_random_r(sdata);
 	if (d <= s) return s;
-	return s + c / ((TF_UNIT_TYPE)~0 / (d - s + 1) + 1);
+	return TF_PRNG_RANGE(c, TF_UNIT_TYPE, s, d);
 }
 
 TF_UNIT_TYPE tf_prng_range(TF_UNIT_TYPE s, TF_UNIT_TYPE d)
diff --git a/tfprng.h b/tfprng.h
index 5fbab0a..3fab0a2 100644
--- a/tfprng.h
+++ b/tfprng.h
@@ -6,6 +6,7 @@
 
 #define TF_PRNG_KEY_SIZE TF_KEY_SIZE
 #define TF_PRNG_SIZE_UNIT TF_SIZE_UNIT
+#define TF_PRNG_RANGE(C, T, S, D) (S + C / ((T)~0 / (D - S + 1) + 1))
 
 size_t tf_prng_datasize(void);
 void tf_prng_seedkey_r(void *sdata, const void *skey);