X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb/blobdiff_plain/0fee61eb2ff1807c5f32a34499ef2753b6fcd9a5..bd6d65e32b835551677456bf286d09ced6859882:/symm/salsa20-core.h

diff --git a/symm/salsa20-core.h b/symm/salsa20-core.h
index 352fec3f..e64e7331 100644
--- a/symm/salsa20-core.h
+++ b/symm/salsa20-core.h
@@ -174,12 +174,13 @@
  * @n@ is decreased appropriately.
  */
 #define SALSA20_OUTBUF(ctx, d, s, n) do {				\
-  size_t _n = (n), _left = SALSA20_OUTSZ - (ctx)->off;			\
-  if (_n > _left) _n = _left;						\
-  (n) -= _n;								\
-  if (!(d)) (ctx)->off += _n;						\
-  else if (s) while (_n--) *(d)++ = (ctx)->b[(ctx)->off++] ^ *(s)++;	\
-  else while (_n--) *(d)++ = (ctx)->b[(ctx)->off++];			\
+  const octet *_p = (ctx)->b + (ctx)->off;				\
+  size_t _n = (n);							\
+									\
+  (ctx)->off += _n;							\
+  if (!(d)) /* nothing to do */;					\
+  else if (!(s)) { memcpy((d), _p, _n); (d) += _n; }			\
+  else while (_n--) *(d)++ = *(s)++ ^ *_p++;				\
 } while (0)
 
 /*----- Variants and naming -----------------------------------------------*/