progress on session_insert_builder

source/core/utils/uuid.cpp

@@ -0,0 +1,75 @@
+#include "matador/utils/uuid.hpp"
+
+#include <random>
+
+namespace matador::utils {
+
+uuid uuid::generate() {
+    std::random_device rd;
+    std::mt19937_64 gen(rd());
+    std::uniform_int_distribution<uint64_t> dist;
+
+    uint64_t high = dist(gen);
+    uint64_t low = dist(gen);
+
+    // Set version to 4 (UUID v4)
+    high &= 0xFFFFFFFFFFFF0FFFULL;
+    high |= 0x0000000000004000ULL;
+
+    // Set variant to 10xx (RFC 4122)
+    low &= 0x3FFFFFFFFFFFFFFFULL;
+    low |= 0x8000000000000000ULL;
+
+    uuid result;
+    result._data[0] = static_cast<uint32_t>(high >> 32);
+    result._data[1] = static_cast<uint32_t>(high & 0xFFFFFFFF);
+    result._data[2] = static_cast<uint32_t>(low >> 32);
+    result._data[3] = static_cast<uint32_t>(low & 0xFFFFFFFF);
+
+    return result;
+}
+
+std::string uuid::str() const {
+    const char* hex = "0123456789abcdef";
+    char out[36]; // UUID string format is 36 characters
+    int pos = 0;
+
+    auto write_hex = [&](uint32_t value, int digits) {
+        for (int i = digits - 1; i >= 0; --i) {
+            out[pos + i] = hex[value & 0xF];
+            value >>= 4;
+        }
+        pos += digits;
+    };
+
+    write_hex(_data[0] >> 16, 8);
+    out[pos++] = '-';
+    write_hex(_data[0] & 0xFFFF, 4);
+    out[pos++] = '-';
+    write_hex(_data[1] >> 16, 4);
+    out[pos++] = '-';
+    write_hex(_data[1] & 0xFFFF, 4);
+    out[pos++] = '-';
+    write_hex(_data[2] >> 16, 4);
+    write_hex(_data[2] & 0xFFFF, 4);
+    write_hex(_data[3], 4);
+
+    return {out, 36};
+}
+
+const uuid::uuid_array& uuid::data() const {
+    return _data;
+}
+
+bool operator==( const uuid& lhs, const uuid& rhs ) {
+    return lhs._data == rhs._data;
+}
+
+bool operator!=( const uuid& lhs, const uuid& rhs ) {
+    return !(lhs == rhs);
+}
+
+bool operator<( const uuid& lhs, const uuid& rhs ) {
+    return lhs._data < rhs._data;
+}
+}