summaryrefslogtreecommitdiffstats
path: root/src/include/blobhash.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/include/blobhash.h47
1 files changed, 47 insertions, 0 deletions
diff --git a/src/include/blobhash.h b/src/include/blobhash.h
new file mode 100644
index 00000000..597884e4
--- /dev/null
+++ b/src/include/blobhash.h
@@ -0,0 +1,47 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+
+#ifndef CEPH_BLOBHASH_H
+#define CEPH_BLOBHASH_H
+
+#include "hash.h"
+
+/*
+- this is to make some of the STL types work with 64 bit values, string hash keys, etc.
+- added when i was using an old STL.. maybe try taking these out and see if things
+ compile now?
+*/
+
+class blobhash {
+public:
+ uint32_t operator()(const char *p, unsigned len) {
+ static rjhash<uint32_t> H;
+ uint32_t acc = 0;
+ while (len >= sizeof(acc)) {
+ acc ^= *(uint32_t*)p;
+ p += sizeof(uint32_t);
+ len -= sizeof(uint32_t);
+ }
+ int sh = 0;
+ while (len) {
+ acc ^= (uint32_t)*p << sh;
+ sh += 8;
+ len--;
+ p++;
+ }
+ return H(acc);
+ }
+};
+
+
+#endif