X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=src%2Flibhashkit%2Fmurmur.cc;h=5ad796b19bb647437cb9886d8be0c866b525980d;hb=6b7d2bf0319e0bd48bd6aa4ad8c56a935f98b0d2;hp=a2ff52163113582b181dd602c8a8e583e2ef894c;hpb=5bb6f975322d3da0caf082b8d890132194d0a4ea;p=awesomized%2Flibmemcached

diff --git a/src/libhashkit/murmur.cc b/src/libhashkit/murmur.cc
index a2ff5216..5ad796b1 100644
--- a/src/libhashkit/murmur.cc
+++ b/src/libhashkit/murmur.cc
@@ -1,88 +1,53 @@
-/*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
- * 
- *  HashKit library
- *
- *  Copyright (C) 2011-2012 Data Differential, http://datadifferential.com/
- *  Copyright (C) 2006-2009 Brian Aker All rights reserved.
- *
- *  Redistribution and use in source and binary forms, with or without
- *  modification, are permitted provided that the following conditions are
- *  met:
- *
- *      * Redistributions of source code must retain the above copyright
- *  notice, this list of conditions and the following disclaimer.
- *
- *      * Redistributions in binary form must reproduce the above
- *  copyright notice, this list of conditions and the following disclaimer
- *  in the documentation and/or other materials provided with the
- *  distribution.
- *
- *      * The names of its contributors may not be used to endorse or
- *  promote products derived from this software without specific prior
- *  written permission.
- *
- *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
 /*
-  "Murmur" hash provided by Austin, tanjent@gmail.com
-  http://murmurhash.googlepages.com/
-
-  Note - This code makes a few assumptions about how your machine behaves -
-
-  1. We can read a 4-byte value from any address without crashing
-  2. sizeof(int) == 4
-
-  And it has a few limitations -
-  1. It will not work incrementally.
-  2. It will not produce the same results on little-endian and big-endian
-  machines.
-
-  Updated to murmur2 hash - BP
+    +--------------------------------------------------------------------+
+    | libmemcached - C/C++ Client Library for memcached                  |
+    +--------------------------------------------------------------------+
+    | Redistribution and use in source and binary forms, with or without |
+    | modification, are permitted under the terms of the BSD license.    |
+    | You should have received a copy of the license in a bundled file   |
+    | named LICENSE; in case you did not receive a copy you can review   |
+    | the terms online at: https://opensource.org/licenses/BSD-3-Clause  |
+    +--------------------------------------------------------------------+
+    | Copyright (c) 2006-2014 Brian Aker   https://datadifferential.com/ |
+    | Copyright (c) 2020 Michael Wallner   <mike@php.net>                |
+    +--------------------------------------------------------------------+
 */
 
 #include "libhashkit/common.h"
 
 #ifdef HAVE_MURMUR_HASH
 
-#include <cstring>
+#  ifdef BYTESWAP_HEADER
+#    include BYTESWAP_HEADER
+#  endif
+
+#  include <cstring>
 
-uint32_t hashkit_murmur(const char *key, size_t length, void *context)
-{
+uint32_t hashkit_murmur(const char *key, size_t length, void *context) {
   /*
     'm' and 'r' are mixing constants generated offline.  They're not
     really 'magic', they just happen to work well.
   */
 
-  const unsigned int m= 0x5bd1e995;
-  const uint32_t seed= (0xdeadbeef * (uint32_t)length);
-  const int r= 24;
-
+  const unsigned int m = 0x5bd1e995;
+  const uint32_t seed = (0xdeadbeef * (uint32_t) length);
+  const int r = 24;
 
   // Initialize the hash to a 'random' value
 
-  uint32_t h= seed ^ (uint32_t)length;
+  uint32_t h = seed ^ (uint32_t) length;
 
   // Mix 4 bytes at a time into the hash
 
-  const unsigned char * data= (const unsigned char *)key;
-  (void)context;
+  const unsigned char *data = (const unsigned char *) key;
+  (void) context;
 
-  while(length >= 4)
-  {
-    unsigned int k;
-    memcpy(&k, data, sizeof(unsigned int));
+  while (length >= 4) {
+    uint32_t k;
+    memcpy(&k, data, sizeof(k));
+#  if WORDS_BIGENDIAN
+    k = BYTESWAP_32(k);
+#  endif
 
     k *= m;
     k ^= k >> r;
@@ -96,15 +61,15 @@ uint32_t hashkit_murmur(const char *key, size_t length, void *context)
   }
 
   // Handle the last few bytes of the input array
-
-  switch(length)
-  {
-  case 3: h ^= ((uint32_t)data[2]) << 16;   /* fall through */
-  case 2: h ^= ((uint32_t)data[1]) << 8;    /* fall through */
-  case 1: h ^= data[0];
-          h *= m;
-  default: break;
-  };
+  if (length) {
+    uint32_t k = 0;
+    memcpy(&k, data, length);
+#  if WORDS_BIGENDIAN
+    k = BYTESWAP_32(k);
+#  endif
+    h ^= k;
+    h *= m;
+  }
 
   /*
     Do a few final mixes of the hash to ensure the last few bytes are
@@ -119,8 +84,7 @@ uint32_t hashkit_murmur(const char *key, size_t length, void *context)
 }
 
 #else
-uint32_t hashkit_murmur(const char *, size_t , void *)
-{
+uint32_t hashkit_murmur(const char *, size_t, void *) {
   return 0;
 }
 #endif