1 files changed, 54 insertions, 0 deletions
diff --git a/utils/hash.h b/utils/hash.h
new file mode 100755
index 00000000..3a60a429
--- /dev/null
+++ b/utils/hash.h
@@ -0,0 +1,54 @@
+#ifndef CDEC_HASH_H
+#define CDEC_HASH_H
+
+#include "murmur_hash.h"
+
+#include "config.h"
+#ifdef HAVE_SPARSEHASH
+# include <google/dense_hash_map>
+# define HASH_MAP google::dense_hash_map
+# define HASH_MAP_RESERVED(h,empty,deleted) do { h.set_empty_key(empty); h.set_deleted_key(deleted); } while(0)
+# define HASH_MAP_EMPTY(h,empty) do { h.set_empty_key(empty); } while(0)
+#else
+# include <tr1/unordered_map>
+# define HASH_MAP std::tr1::unordered_map
+# define HASH_MAP_RESERVED(h,empty,deleted)
+# define HASH_MAP_EMPTY(h,empty)
+#endif
+
+#include <boost/functional/hash.hpp>
+
+// assumes C is POD
+template <class C>
+struct murmur_hash
+{
+  typedef MurmurInt return_type;
+  typedef C /*const&*/ argument_type;
+  return_type operator()(argument_type const& c) const {
+    return MurmurHash((void*)&c,sizeof(c));
+  }
+};
+
+// murmur_hash_array isn't std guaranteed safe (you need to use string::data())
+template <>
+struct murmur_hash<std::string>
+{
+  typedef MurmurInt return_type;
+  typedef std::string /*const&*/ argument_type;
+  return_type operator()(argument_type const& c) const {
+    return MurmurHash(c.data(),c.size());
+  }
+};
+
+// uses begin(),size() assuming contiguous layout and POD
+template <class C>
+struct murmur_hash_array
+{
+  typedef MurmurInt return_type;
+  typedef C /*const&*/ argument_type;
+  return_type operator()(argument_type const& c) const {
+    return MurmurHash(&*c.begin(),c.size()*sizeof(*c.begin()));
+  }
+};
+
+#endif