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-rw-r--r--security/sandbox/chromium/base/third_party/superfasthash/superfasthash.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/third_party/superfasthash/superfasthash.c b/security/sandbox/chromium/base/third_party/superfasthash/superfasthash.c
new file mode 100644
index 0000000000..6e7687e131
--- /dev/null
+++ b/security/sandbox/chromium/base/third_party/superfasthash/superfasthash.c
@@ -0,0 +1,84 @@
+// Copyright (c) 2010, Paul Hsieh
+// 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.
+// * Neither my name, Paul Hsieh, nor the names of any other contributors to the
+// code use 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.
+
+#include <stdint.h>
+#include <stdlib.h>
+#undef get16bits
+#if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \
+ || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__)
+#define get16bits(d) (*((const uint16_t *) (d)))
+#endif
+
+#if !defined (get16bits)
+#define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)\
+ +(uint32_t)(((const uint8_t *)(d))[0]) )
+#endif
+
+uint32_t SuperFastHash (const char * data, int len) {
+uint32_t hash = len, tmp;
+int rem;
+
+ if (len <= 0 || data == NULL) return 0;
+
+ rem = len & 3;
+ len >>= 2;
+
+ /* Main loop */
+ for (;len > 0; len--) {
+ hash += get16bits (data);
+ tmp = (get16bits (data+2) << 11) ^ hash;
+ hash = (hash << 16) ^ tmp;
+ data += 2*sizeof (uint16_t);
+ hash += hash >> 11;
+ }
+
+ /* Handle end cases */
+ switch (rem) {
+ case 3: hash += get16bits (data);
+ hash ^= hash << 16;
+ hash ^= ((signed char)data[sizeof (uint16_t)]) << 18;
+ hash += hash >> 11;
+ break;
+ case 2: hash += get16bits (data);
+ hash ^= hash << 11;
+ hash += hash >> 17;
+ break;
+ case 1: hash += (signed char)*data;
+ hash ^= hash << 10;
+ hash += hash >> 1;
+ }
+
+ /* Force "avalanching" of final 127 bits */
+ hash ^= hash << 3;
+ hash += hash >> 5;
+ hash ^= hash << 4;
+ hash += hash >> 17;
+ hash ^= hash << 25;
+ hash += hash >> 6;
+
+ return hash;
+}