From: Simon Wilkinson <sxw@your-file-system.com>
Date: Mon, 29 Oct 2012 19:02:03 +0000 (+0000)
Subject: opr: Add opr_jhash_int2 function
X-Git-Tag: openafs-stable-1_8_0pre1~1844
X-Git-Url: https://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=07372cf7e76acf62eb26908977e2682338c85ac1;hp=dce5e012fedb3efc9e7acd9c443b7ec2caaf47ae

opr: Add opr_jhash_int2 function

Add a function to jhash that can be used to hash a pair of unsigned
integers (or other stuff that can cast to them) without having to build
up an array.

Provide a couple of tests for the new function

Change-Id: I594848f64316fb459eff565933691f560512ca79
Reviewed-on: http://gerrit.openafs.org/8354
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---

diff --git a/src/opr/jhash.h b/src/opr/jhash.h
index 6e9bc79..5c6e3ad 100644
--- a/src/opr/jhash.h
+++ b/src/opr/jhash.h
@@ -103,6 +103,21 @@ opr_jhash_int(afs_uint32 a, afs_uint32 initval) {
    return c;
 }
 
+/* and one to do two ints */
+
+static_inline afs_uint32
+opr_jhash_int2(afs_uint32 a, afs_uint32 b, afs_uint32 initval)
+{
+   afs_uint32 c;
+
+   a += 0xdeadbeef + 8 + initval;
+   b += 0xdeadbeef + 8 + initval;
+   c =  0xdeadbeef + 8 + initval;
+   opr_jhash_final(a, b, c);
+
+   return c;
+}
+
 static_inline afs_uint32
 opr_jhash_opaque(const void *val, size_t length, afs_uint32 initval)
 {
diff --git a/tests/opr/jhash-t.c b/tests/opr/jhash-t.c
index c17a7fb..707cd06 100644
--- a/tests/opr/jhash-t.c
+++ b/tests/opr/jhash-t.c
@@ -39,7 +39,7 @@
 int
 main(int argc, char **argv)
 {
-   plan(11);
+   plan(13);
    uint32_t test[] = {3526055646UL, 2064483663UL, 3234460805UL, 3963629775UL};
 
    is_int(256, opr_jhash_size(8), "opr_jhash_size returns expected value");
@@ -57,6 +57,11 @@ main(int argc, char **argv)
    is_int(1100796964, opr_jhash_int(test[0], 0),
           "single value works through jhash_int");
 
+   is_int(3704403432, opr_jhash(test, 2, 0),
+	  "Hashing two values works");
+   is_int(3704403432, opr_jhash_int2(test[0], test[1], 0),
+	  "jhash_int2 gives same result");
+
    is_int(0xdeadbeef, opr_jhash_opaque("", 0, 0),
 	  "Hashing an empty string works");