Added FNV1a/MurmurHash3/CityHash

src/hash/FNV1a.cpp

@@ -0,0 +1,27 @@
+#include<hgl/util/hash/Hash.h>
+
+namespace hgl
+{
+    namespace util
+    {
+        namespace
+        {
+            uint32_t FNV1aHash(const void *key, int len)
+            {
+                //本代码来自Github Copilot
+
+                //FNV-1a 是一种简单且高效的哈希算法，适用于大多数场景。它具有良好的分布性和较快的计算速度。
+
+                const uint8_t *data = (const uint8_t *)key;
+                uint32_t hash = 2166136261u;
+
+                for (int i = 0; i < len; ++i) {
+                    hash ^= data[i];
+                    hash *= 16777619u;
+                }
+
+                return hash;
+            }
+        }//namespace
+    }//namespace util
+}//namespace hgl

src/hash/GoogleCityHash.cpp

@@ -0,0 +1,5 @@
+// source codes repository: https://github.com/google/cityhash.git
+
+// vcpkg： cityhash, cityhash[sse]
+
+

src/hash/MurmurHash3.cpp

@@ -0,0 +1,65 @@
+#include<hgl/util/hash/Hash.h>
+
+namespace hgl
+{
+    namespace util
+    {
+        namespace
+        {
+            //本代码来自Github Copilot
+            //MurmurHash 是一种高性能的哈希算法，特别适用于哈希表。它具有良好的分布性和较低的碰撞率。
+
+            uint32_t MurmurHash3(const void *key, int len, uint32_t seed)
+            {
+                const uint8_t *data = (const uint8_t *)key;
+                const int nblocks = len / 4;
+                uint32_t h1 = seed;
+
+                const uint32_t c1 = 0xcc9e2d51;
+                const uint32_t c2 = 0x1b873593;
+
+                // Body
+                const uint32_t *blocks = (const uint32_t *)(data + nblocks * 4);
+                for (int i = -nblocks; i; i++) {
+                    uint32_t k1 = blocks[i];
+
+                    k1 *= c1;
+                    k1 = (k1 << 15) | (k1 >> (32 - 15));
+                    k1 *= c2;
+
+                    h1 ^= k1;
+                    h1 = (h1 << 13) | (h1 >> (32 - 13));
+                    h1 = h1 * 5 + 0xe6546b64;
+                }
+
+                // Tail
+                const uint8_t *tail = (const uint8_t *)(data + nblocks * 4);
+                uint32_t k1 = 0;
+
+                switch (len & 3)
+                {
+                    case 3:
+                        k1 ^= tail[2] << 16;
+                    case 2:
+                        k1 ^= tail[1] << 8;
+                    case 1:
+                        k1 ^= tail[0];
+                        k1 *= c1;
+                        k1 = (k1 << 15) | (k1 >> (32 - 15));
+                        k1 *= c2;
+                        h1 ^= k1;
+                }
+
+                // Finalization
+                h1 ^= len;
+                h1 ^= h1 >> 16;
+                h1 *= 0x85ebca6b;
+                h1 ^= h1 >> 13;
+                h1 *= 0xc2b2ae35;
+                h1 ^= h1 >> 16;
+
+                return h1;
+            }
+        }//namespace
+    }//namespace util
+}//namespace hgl