Merge in PMurHash by Shane Day, a MurmurHash3_x86_32 implementation that should work on virtually all platforms regardless of endian-ness or alignment issues.

git-svn-id: http://smhasher.googlecode.com/svn/trunk@146 77a7d1d3-4c08-bdc2-d393-d5859734b01a

1 files changed, 64 insertions, 0 deletions

diff --git a/PMurHash.h b/PMurHash.h
new file mode 100644
index 0000000..28ead00
--- /dev/null
+++ b/PMurHash.h
@@ -0,0 +1,64 @@
+/*-----------------------------------------------------------------------------
+ * MurmurHash3 was written by Austin Appleby, and is placed in the public
+ * domain.
+ *
+ * This implementation was written by Shane Day, and is also public domain.
+ *
+ * This is a portable ANSI C implementation of MurmurHash3_x86_32 (Murmur3A)
+ * with support for progressive processing.
+ */
+
+/* ------------------------------------------------------------------------- */
+/* Determine what native type to use for uint32_t */
+
+/* We can't use the name 'uint32_t' here because it will conflict with
+ * any version provided by the system headers or application. */
+
+/* First look for special cases */
+#if defined(_MSC_VER)
+  #define MH_UINT32 unsigned long
+#endif
+
+/* If the compiler says it's C99 then take its word for it */
+#if !defined(MH_UINT32) && ( \
+     defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L )
+  #include <stdint.h>
+  #define MH_UINT32 uint32_t
+#endif
+
+/* Otherwise try testing against max value macros from limit.h */
+#if !defined(MH_UINT32)
+  #include  <limits.h>
+  #if   (USHRT_MAX == 0xffffffffUL)
+    #define MH_UINT32 unsigned short
+  #elif (UINT_MAX == 0xffffffffUL)
+    #define MH_UINT32 unsigned int
+  #elif (ULONG_MAX == 0xffffffffUL)
+    #define MH_UINT32 unsigned long
+  #endif
+#endif
+
+#if !defined(MH_UINT32)
+  #error Unable to determine type name for unsigned 32-bit int
+#endif
+
+/* I'm yet to work on a platform where 'unsigned char' is not 8 bits */
+#define MH_UINT8  unsigned char
+
+
+/* ------------------------------------------------------------------------- */
+/* Prototypes */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void PMurHash32_Process(MH_UINT32 *ph1, MH_UINT32 *pcarry, const void *key, int len);
+MH_UINT32 PMurHash32_Result(MH_UINT32 h1, MH_UINT32 carry, MH_UINT32 total_length);
+MH_UINT32 PMurHash32(MH_UINT32 seed, const void *key, int len);
+
+void PMurHash32_test(const void *key, int len, MH_UINT32 seed, void *out);
+
+#ifdef __cplusplus
+}
+#endif