Added DnsRecords class.

src/base/net/dns/DnsRecords.cpp

@@ -0,0 +1,107 @@
+/* XMRig
+ * Copyright (c) 2018-2021 SChernykh   <https://github.com/SChernykh>
+ * Copyright (c) 2016-2021 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <uv.h>
+
+
+#include "base/net/dns/DnsRecords.h"
+
+
+const xmrig::DnsRecord &xmrig::DnsRecords::get(DnsRecord::Type prefered) const
+{
+    static const DnsRecord defaultRecord;
+
+    if (isEmpty()) {
+        return defaultRecord;
+    }
+
+    const size_t ipv4 = m_ipv4.size();
+    const size_t ipv6 = m_ipv6.size();
+
+    if (ipv6 && (prefered == DnsRecord::AAAA || !ipv4)) {
+        return m_ipv6[ipv6 == 1 ? 0 : static_cast<size_t>(rand()) % ipv6];
+    }
+
+    if (ipv4) {
+        return m_ipv4[ipv4 == 1 ? 0 : static_cast<size_t>(rand()) % ipv4];
+    }
+
+    return defaultRecord;
+}
+
+
+size_t xmrig::DnsRecords::count(DnsRecord::Type type) const
+{
+    if (type == DnsRecord::A) {
+        return m_ipv4.size();
+    }
+
+    if (type == DnsRecord::AAAA) {
+        return m_ipv6.size();
+    }
+
+    return m_ipv4.size() + m_ipv6.size();
+}
+
+
+void xmrig::DnsRecords::clear()
+{
+    m_ipv4.clear();
+    m_ipv6.clear();
+}
+
+
+void xmrig::DnsRecords::parse(addrinfo *res)
+{
+    clear();
+
+    addrinfo *ptr = res;
+    size_t ipv4   = 0;
+    size_t ipv6   = 0;
+
+    while (ptr != nullptr) {
+        if (ptr->ai_family == AF_INET) {
+            ++ipv4;
+        }
+        else if (ptr->ai_family == AF_INET6) {
+            ++ipv6;
+        }
+
+        ptr = ptr->ai_next;
+    }
+
+    if (ipv4 == 0 && ipv6 == 0) {
+        return;
+    }
+
+    m_ipv4.reserve(ipv4);
+    m_ipv6.reserve(ipv6);
+
+    ptr = res;
+    while (ptr != nullptr) {
+        if (ptr->ai_family == AF_INET) {
+            m_ipv4.emplace_back(ptr);
+        }
+        else if (ptr->ai_family == AF_INET6) {
+            m_ipv6.emplace_back(ptr);
+        }
+
+        ptr = ptr->ai_next;
+    }
+}