siphash: Simplify helper function W64's signature

[ccan] / ccan / siphash / siphash.c

diff --git a/ccan/siphash/siphash.c b/ccan/siphash/siphash.c
index 93eac040fc14b9181b00785adb829076de346718..b711b30a1231eb97f6378ef27210aaee62a912b0 100644 (file)
--- a/ccan/siphash/siphash.c
+++ b/ccan/siphash/siphash.c
@@ -2,6 +2,8 @@
 
 #include <ccan/endian/endian.h>
 
+#include <string.h>
+
 #include "siphash.h"
 
 typedef uint64_t u64;
@@ -23,8 +25,13 @@ enum sip_index { A=0, B=2, C=1, D=3, E=4 };
         SIP_HALF_ROUND((W)[C], (W)[B], (W)[A], (W)[D], 17, 21); \
     } while(0)
 
-/* Load a 64-bit word as little endian */
-#define W64(S,I) (le64_to_cpu(*((u64 *)(S) + (I))))
+
+static inline u64 W64(const unsigned char *p, size_t j)
+{
+    uint64_t x;
+    memcpy(&x, p + j*sizeof(x), sizeof(x));
+    return le64_to_cpu(x);
+}
 
 static void siphash_init(u64 v[5], const unsigned char key[16])
 {
@@ -36,18 +43,18 @@ static void siphash_init(u64 v[5], const unsigned char key[16])
 }
 
 /* Load the last 0-7 bytes of `in` and put in len & 255 */
-static void siphash_epilogue(u64 *m, const void *in, size_t len)
+static void siphash_epilogue(u64 *m, const unsigned char *in, size_t len)
 {
-    in = (char *)in + (len & ~7);
+    in += len & ~(size_t)7;
     *m = (u64)(len & 255) << 56;
     switch (len & 7) {
-        case 7: *m |= (u64)*((unsigned char *)in+6) << 48;
-        case 6: *m |= (u64)*((unsigned char *)in+5) << 40;
-        case 5: *m |= (u64)*((unsigned char *)in+4) << 32;
-        case 4: *m |= (u64)*((unsigned char *)in+3) << 24;
-        case 3: *m |= (u64)*((unsigned char *)in+2) << 16;
-        case 2: *m |= (u64)*((unsigned char *)in+1) << 8;
-        case 1: *m |= (u64)*((unsigned char *)in+0);
+        case 7: *m |= (u64) in[6] << 48;
+        case 6: *m |= (u64) in[5] << 40;
+        case 5: *m |= (u64) in[4] << 32;
+        case 4: *m |= (u64) in[3] << 24;
+        case 3: *m |= (u64) in[2] << 16;
+        case 2: *m |= (u64) in[1] << 8;
+        case 1: *m |= (u64) in[0];
         case 0: ;
     }
 }