Fixed compiler error

[libcds.git] / cds / container / details / feldman_hashmap_base.h

diff --git a/cds/container/details/feldman_hashmap_base.h b/cds/container/details/feldman_hashmap_base.h
index d72bd284fe5c26baed758e8fb4997bfd6e5f8029..a6dbab0766a3c59aab39ad36a1b81ea7a73c251a 100644 (file)
--- a/cds/container/details/feldman_hashmap_base.h
+++ b/cds/container/details/feldman_hashmap_base.h
@@ -1,11 +1,11 @@
 /*
     This file is a part of libcds - Concurrent Data Structures library
 
-    (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2016
+    (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2017
 
     Source code repo: http://github.com/khizmax/libcds/
     Download: http://sourceforge.net/projects/libcds/files/
-    
+
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions are met:
 
@@ -25,7 +25,7 @@
     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.     
+    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
 #ifndef CDSLIB_CONTAINER_DETAILS_FELDMAN_HASHMAP_BASE_H
@@ -54,6 +54,14 @@ namespace cds { namespace container {
         /// \p FeldmanHashMap level statistics
         typedef cds::intrusive::feldman_hashset::level_statistics level_statistics;
 
+        /// Key size option
+        /**
+            @copydetails cds::container::feldman_hashmap::traits::hash_size
+        */
+        template <size_t Size>
+        using hash_size = cds::intrusive::feldman_hashset::hash_size< Size >;
+
+
         /// \p FeldmanHashMap traits
         struct traits
         {
@@ -65,7 +73,7 @@ namespace cds { namespace container {
                 <a href="https://en.wikipedia.org/wiki/CityHash">CityHash</a>
                 or its successor <a href="https://code.google.com/p/farmhash/">FarmHash</a>.
 
-                If you use a fixed-sized key you may use it directly instead of a hash.
+                If you use a fixed-sized key you can use it directly instead of a hash.
                 In such case \p %traits::hash should be specified as \p opt::none.
                 However, if you want to use the hash values or if your key type is not fixed-sized
                 you must specify a proper hash functor in your traits.
@@ -122,6 +130,34 @@ namespace cds { namespace container {
             */
             typedef opt::none hash;
 
+            /// The size of hash value in bytes
+            /**
+                By default, the size of hash value is <tt>sizeof( hash_type )</tt>
+                where \p hash_type is type of \p hash() result or <tt>sizeof( key )</tt> if you use fixed-sized key.
+
+                Sometimes that size is wrong, for example, for that 6-byte key:
+                \code
+                struct key_type {
+                    uint32_t    key;
+                    uint16_t    subkey;
+                };
+
+                static_assert( sizeof( key_type ) == 6, "Key type size mismatch" );
+                \endcode
+                Here <tt>sizeof( key_type ) == 8</tt> so \p static_assert will be thrown.
+
+                For that case you can specify \p hash_size explicitly.
+
+                Value \p 0 means auto-calculated <tt>sizeof( key_type )</tt>.
+            */
+            static CDS_CONSTEXPR size_t const hash_size = 0;
+
+            /// Hash splitter
+            /**
+                @copydetails cds::intrusive::feldman_hashset::traits::hash_splitter
+            */
+            typedef cds::opt::none hash_splitter;
+
             /// Hash comparing functor
             /**
                 @copydetails cds::intrusive::feldman_hashset::traits::compare
@@ -179,6 +215,8 @@ namespace cds { namespace container {
             Supported \p Options are:
             - \p opt::hash - a hash functor, default is \p std::hash
                 @copydetails traits::hash
+            - \p feldman_hashmap::hash_size - the size of hash value in bytes.
+                @copydetails traits::hash_size
             - \p opt::allocator - item allocator
                 @copydetails traits::allocator
             - \p opt::node_allocator - array node allocator.
@@ -243,20 +281,20 @@ namespace cds { namespace container {
 
                 template <typename Q>
                 node_type(hasher& h, Q const& key)
-                    : m_Value(std::move(std::make_pair(key, mapped_type())))
-                    , m_hash(h(m_Value.first))
+                    : m_Value( std::move( std::make_pair( key_type( key ), mapped_type())))
+                    , m_hash( h( m_Value.first ))
                 {}
 
                 template <typename Q, typename U >
                 node_type(hasher& h, Q const& key, U const& val)
-                    : m_Value(std::move(std::make_pair(key, mapped_type(val))))
-                    , m_hash(h(m_Value.first))
+                    : m_Value( std::move( std::make_pair( key_type( key ), mapped_type(val))))
+                    , m_hash( h( m_Value.first ))
                 {}
 
                 template <typename Q, typename... Args>
                 node_type(hasher& h, Q&& key, Args&&... args)
-                    : m_Value(std::move(std::make_pair(std::forward<Q>(key), std::move(mapped_type(std::forward<Args>(args)...)))))
-                    , m_hash(h(m_Value.first))
+                    : m_Value( std::move(std::make_pair( key_type( std::forward<Q>(key)), std::move( mapped_type(std::forward<Args>(args)...)))))
+                    , m_hash( h( m_Value.first ))
                 {}
             };
 
@@ -292,7 +330,7 @@ namespace cds { namespace container {
 
                 template <typename Q, typename... Args>
                 node_type( hasher /*h*/, Q&& key, Args&&... args )
-                    : m_Value( std::make_pair( key_type( std::forward<Q>( key )), mapped_type( std::forward<Args>(args)...) ))
+                    : m_Value( std::make_pair( key_type( std::forward<Q>( key )), mapped_type( std::forward<Args>(args)...)))
                 {}
             };