[245] Additional Sockaddr functionality for better multicast usage.

core/include/userver/engine/io/sockaddr.hpp

@@ -55,9 +55,23 @@ class Sockaddr final {
         ::memcpy(&data_, data, Sockaddr::Addrlen(domain));
     }
 
+    /// @brief Creates address of an IP socket with passed address.
+    static Sockaddr MakeIPSocketAddress(const char* ip_address);
+
     /// @brief Creates address of a Unix socket located at the specified path.
     static Sockaddr MakeUnixSocketAddress(std::string_view path);
 
+    /// @brief Creates the IPv6 wildcard address `[::]:0` that also handles IPv4
+    /// connections.
+    ///
+    /// A program needs to support only this API type to support IPv4 and IPv6.
+    static Sockaddr MakeInaddrAny() noexcept;
+
+    /// @brief Creates the IPv4 only wildcard address `0.0.0.0:0`.
+    ///
+    /// Prefer a more generic MakeInaddrAny() function if not sure.
+    static Sockaddr MakeIPv4InaddrAny() noexcept;
+
     /// @brief Creates the IPv6 loopback address `[::1]:0` that also handles IPv4
     /// connections.
     ///

core/src/engine/io/sockaddr.cpp

@@ -18,6 +18,21 @@ USERVER_NAMESPACE_BEGIN
 
 namespace engine::io {
 
+Sockaddr Sockaddr::MakeIPSocketAddress(const char* ip_address) {
+    Sockaddr addr;
+    auto* ipv4_sa = addr.As<struct sockaddr_in>();
+    if (inet_pton(AF_INET, ip_address, &ipv4_sa->sin_addr) == 1) {
+        ipv4_sa->sin_family = AF_INET;
+        return addr;
+    }
+    auto* ipv6_sa = addr.As<struct sockaddr_in6>();
+    if (inet_pton(AF_INET6, ip_address, &ipv6_sa->sin6_addr) == 1) {
+        ipv6_sa->sin6_family = AF_INET6;
+        return addr;
+    }
+    throw AddrException(fmt::format("Invalid IP address: {}", ip_address));
+}
+
 Sockaddr Sockaddr::MakeUnixSocketAddress(std::string_view path) {
     Sockaddr addr;
     auto* sa = addr.As<struct sockaddr_un>();
@@ -39,6 +54,26 @@ Sockaddr Sockaddr::MakeUnixSocketAddress(std::string_view path) {
     return addr;
 }
 
+Sockaddr Sockaddr::MakeInaddrAny() noexcept {
+    Sockaddr addr;
+    auto* sa = addr.As<struct sockaddr_in6>();
+    sa->sin6_family = AF_INET6;
+    sa->sin6_addr = in6addr_any;
+    UASSERT(sa->sin6_port == 0);
+    return addr;
+}
+
+Sockaddr Sockaddr::MakeIPv4InaddrAny() noexcept {
+    Sockaddr addr;
+    auto* sa = addr.As<struct sockaddr_in>();
+    sa->sin_family = AF_INET;
+    // may be implemented as a macro
+    // NOLINTNEXTLINE(hicpp-no-assembler, readability-isolate-declaration)
+    sa->sin_addr.s_addr = htonl(INADDR_ANY);
+    UASSERT(sa->sin_port == 0);
+    return addr;
+}
+
 Sockaddr Sockaddr::MakeLoopbackAddress() noexcept {
     Sockaddr addr;
     auto* sa = addr.As<struct sockaddr_in6>();

core/src/engine/io/socket_test.cpp

@@ -474,10 +474,8 @@ UTEST(Socket, UdpIpMreqIPv4) {
 
         auto receiver = engine::io::Socket(engine::io::AddrDomain::kInet, engine::io::SocketType::kDgram);
 
-        sockaddr_in any_addr{};
-        any_addr.sin_family = AF_INET;
-        any_addr.sin_port = htons(kPort);
-        any_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+        auto any_addr = engine::io::Sockaddr::MakeIPv4InaddrAny();
+        any_addr.SetPort(kPort);
         receiver.Bind(engine::io::Sockaddr(&any_addr));
 
         engine::io::IpMreq mreq(kGroup, 0);
@@ -500,10 +498,8 @@ UTEST(Socket, UdpIpMreqIPv6) {
 
     auto receiver = engine::io::Socket(engine::io::AddrDomain::kInet6, engine::io::SocketType::kDgram);
 
-    sockaddr_in6 any_addr{};
-    any_addr.sin6_family = AF_INET6;
-    any_addr.sin6_port = htons(kPort);
-    any_addr.sin6_addr = in6addr_any;
+    auto any_addr = engine::io::Sockaddr::MakeInaddrAny();
+    any_addr.SetPort(kPort);
     receiver.Bind(engine::io::Sockaddr(&any_addr));
 
     engine::io::IpMreq mreq(kGroup, 0);
@@ -522,11 +518,8 @@ UTEST_MT(Socket, UdpIpMreqMultipleReceiversIPv6, 3) {
     static constexpr const char* kGroup = "ff02::42";
     static constexpr int packets_count = 3;
 
-    sockaddr_in6 raw_multiaddr{};
-    raw_multiaddr.sin6_family = AF_INET6;
-    raw_multiaddr.sin6_port = htons(kPort);
-    inet_pton(AF_INET6, kGroup, &raw_multiaddr.sin6_addr);
-    io::Sockaddr multiaddr(&raw_multiaddr);
+    auto multiaddr = engine::io::Sockaddr::MakeIPSocketAddress(kGroup);
+    multiaddr.SetPort(kPort);
     io::IpMreq mreq(kGroup, 0);
 
     std::vector<engine::TaskWithResult<void>> tasks;
@@ -535,10 +528,8 @@ UTEST_MT(Socket, UdpIpMreqMultipleReceiversIPv6, 3) {
         const auto& receiver =
             receivers.emplace_back(std::make_shared<io::Socket>(io::AddrDomain::kInet6, io::SocketType::kDgram));
 
-        sockaddr_in6 any{};
-        any.sin6_family = AF_INET6;
-        any.sin6_port = htons(kPort);
-        any.sin6_addr = in6addr_any;
+        auto any = engine::io::Sockaddr::MakeInaddrAny();
+        any.SetPort(kPort);
         receiver->Bind(io::Sockaddr(&any));
         io::AddMembership(*receiver, mreq);