Revert async nameresolution on Unix

src/libraries/Common/src/Interop/Unix/System.Native/Interop.HostEntry.cs

@@ -32,19 +32,9 @@ internal unsafe struct HostEntry
             internal int IPAddressCount;       // Number of IP addresses in the list
         }
 
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_PlatformSupportsGetAddrInfoAsync")]
-        internal static extern bool PlatformSupportsGetAddrInfoAsync();
-
         [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetHostEntryForName")]
         internal static extern unsafe int GetHostEntryForName(string address, AddressFamily family, HostEntry* entry);
 
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetHostEntryForNameAsync")]
-        internal static extern unsafe int GetHostEntryForNameAsync(
-            string address,
-            AddressFamily family,
-            HostEntry* entry,
-            delegate* unmanaged<HostEntry*, int, void> callback);
-
         [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_FreeHostEntry")]
         internal static extern unsafe void FreeHostEntry(HostEntry* entry);
     }

src/libraries/Native/Unix/Common/pal_config.h.in

@@ -10,7 +10,6 @@
 #cmakedefine01 HAVE_F_FULLFSYNC
 #cmakedefine01 HAVE_O_CLOEXEC
 #cmakedefine01 HAVE_GETIFADDRS
-#cmakedefine01 HAVE_GETADDRINFO_A
 #cmakedefine01 HAVE_UTSNAME_DOMAINNAME
 #cmakedefine01 HAVE_STAT64
 #cmakedefine01 HAVE_FORK

src/libraries/Native/Unix/System.Native/entrypoints.c

@@ -115,9 +115,7 @@ static const Entry s_sysNative[] =
     DllImportEntry(SystemNative_ReadEvents)
     DllImportEntry(SystemNative_CreateNetworkChangeListenerSocket)
     DllImportEntry(SystemNative_CloseNetworkChangeListenerSocket)
-    DllImportEntry(SystemNative_PlatformSupportsGetAddrInfoAsync)
     DllImportEntry(SystemNative_GetHostEntryForName)
-    DllImportEntry(SystemNative_GetHostEntryForNameAsync)
     DllImportEntry(SystemNative_FreeHostEntry)
     DllImportEntry(SystemNative_GetNameInfo)
     DllImportEntry(SystemNative_GetDomainName)

src/libraries/Native/Unix/System.Native/extra_libs.cmake

@@ -13,8 +13,4 @@ macro(append_extra_system_libs NativeLibsExtra)
     if (CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
         list(APPEND ${NativeLibsExtra} "-framework Foundation")
     endif ()
-
-    if (CLR_CMAKE_TARGET_LINUX AND HAVE_GETADDRINFO_A)
-        list(APPEND ${NativeLibsExtra} anl)
-    endif ()
 endmacro()

src/libraries/Native/Unix/System.Native/pal_networking.c

@@ -60,10 +60,6 @@
 #if HAVE_LINUX_CAN_H
 #include <linux/can.h>
 #endif
-#if HAVE_GETADDRINFO_A
-#include <signal.h>
-#include <stdatomic.h>
-#endif
 #if HAVE_SYS_FILIO_H
 #include <sys/filio.h>
 #endif
@@ -339,14 +335,37 @@ static int32_t CopySockAddrToIPAddress(sockaddr* addr, sa_family_t family, IPAdd
     return -1;
 }
 
-static int32_t GetHostEntries(const uint8_t* address, struct addrinfo* info, HostEntry* entry)
+int32_t SystemNative_GetHostEntryForName(const uint8_t* address, int32_t addressFamily, HostEntry* entry)
 {
+    if (address == NULL || entry == NULL)
+    {
+        return GetAddrInfoErrorFlags_EAI_BADARG;
+    }
+
     int32_t ret = GetAddrInfoErrorFlags_EAI_SUCCESS;
 
+    struct addrinfo* info = NULL;
 #if HAVE_GETIFADDRS
     struct ifaddrs* addrs = NULL;
 #endif
 
+    sa_family_t platformFamily;
+    if (!TryConvertAddressFamilyPalToPlatform(addressFamily, &platformFamily))
+    {
+        return GetAddrInfoErrorFlags_EAI_FAMILY;
+    }
+
+    struct addrinfo hint;
+    memset(&hint, 0, sizeof(struct addrinfo));
+    hint.ai_flags = AI_CANONNAME;
+    hint.ai_family = platformFamily;
+
+    int result = getaddrinfo((const char*)address, NULL, &hint, &info);
+    if (result != 0)
+    {
+        return ConvertGetAddrInfoAndGetNameInfoErrorsToPal(result);
+    }
+
     entry->CanonicalName = NULL;
     entry->Aliases = NULL;
     entry->IPAddressList = NULL;
@@ -374,8 +393,7 @@ static int32_t GetHostEntries(const uint8_t* address, struct addrinfo* info, Hos
 
 #if HAVE_GETIFADDRS
     char name[_POSIX_HOST_NAME_MAX];
-
-    int result = gethostname((char*)name, _POSIX_HOST_NAME_MAX);
+    result = gethostname((char*)name, _POSIX_HOST_NAME_MAX);
 
     bool includeIPv4Loopback = true;
     bool includeIPv6Loopback = true;
@@ -425,8 +443,6 @@ static int32_t GetHostEntries(const uint8_t* address, struct addrinfo* info, Hos
             }
         }
     }
-#else
-    (void)address;
 #endif
 
     if (entry->IPAddressCount > 0)
@@ -503,158 +519,6 @@ static int32_t GetHostEntries(const uint8_t* address, struct addrinfo* info, Hos
     return ret;
 }
 
-#if HAVE_GETADDRINFO_A
-struct GetAddrInfoAsyncState
-{
-    struct gaicb gai_request;
-    struct gaicb* gai_requests;
-    struct sigevent sigevent;
-
-    struct addrinfo hint;
-    HostEntry* entry;
-    GetHostEntryForNameCallback callback;
-    char address[];
-};
-
-static void GetHostEntryForNameAsyncComplete(sigval_t context)
-{
-    struct GetAddrInfoAsyncState* state = (struct GetAddrInfoAsyncState*)context.sival_ptr;
-
-    atomic_thread_fence(memory_order_acquire);
-
-    GetHostEntryForNameCallback callback = state->callback;
-
-    int ret = ConvertGetAddrInfoAndGetNameInfoErrorsToPal(gai_error(&state->gai_request));
-
-    if (ret == 0)
-    {
-        const uint8_t* address = (const uint8_t*)state->address;
-        struct addrinfo* info = state->gai_request.ar_result;
-
-        ret = GetHostEntries(address, info, state->entry);
-    }
-
-    assert(callback != NULL);
-    callback(state->entry, ret);
-
-    free(state);
-}
-#endif
-
-static bool TrySetAddressFamily(int32_t addressFamily, struct addrinfo* hint)
-{
-    sa_family_t platformFamily;
-    if (!TryConvertAddressFamilyPalToPlatform(addressFamily, &platformFamily))
-    {
-        return false;
-    }
-
-    memset(hint, 0, sizeof(struct addrinfo));
-
-    hint->ai_flags = AI_CANONNAME;
-    hint->ai_family = platformFamily;
-
-    return true;
-}
-
-int32_t SystemNative_PlatformSupportsGetAddrInfoAsync()
-{
-    return HAVE_GETADDRINFO_A;
-}
-
-int32_t SystemNative_GetHostEntryForName(const uint8_t* address, int32_t addressFamily, HostEntry* entry)
-{
-    if (address == NULL || entry == NULL)
-    {
-        return GetAddrInfoErrorFlags_EAI_BADARG;
-    }
-
-    struct addrinfo hint;
-    if (!TrySetAddressFamily(addressFamily, &hint))
-    {
-        return GetAddrInfoErrorFlags_EAI_FAMILY;
-    }
-
-    struct addrinfo* info = NULL;
-
-    int result = getaddrinfo((const char*)address, NULL, &hint, &info);
-    if (result != 0)
-    {
-        return ConvertGetAddrInfoAndGetNameInfoErrorsToPal(result);
-    }
-
-    return GetHostEntries(address, info, entry);
-}
-
-int32_t SystemNative_GetHostEntryForNameAsync(const uint8_t* address, int32_t addressFamily, HostEntry* entry, GetHostEntryForNameCallback callback)
-{
-#if HAVE_GETADDRINFO_A
-    if (address == NULL || entry == NULL)
-    {
-        return GetAddrInfoErrorFlags_EAI_BADARG;
-    }
-
-    size_t addrlen = strlen((const char*)address);
-
-    if (addrlen > _POSIX_HOST_NAME_MAX)
-    {
-        return GetAddrInfoErrorFlags_EAI_BADARG;
-    }
-
-    struct GetAddrInfoAsyncState* state = malloc(sizeof(*state) + addrlen + 1);
-
-    if (state == NULL)
-    {
-        return GetAddrInfoErrorFlags_EAI_MEMORY;
-    }
-
-    if (!TrySetAddressFamily(addressFamily, &state->hint))
-    {
-        free(state);
-        return GetAddrInfoErrorFlags_EAI_FAMILY;
-    }
-
-    memcpy(state->address, address, addrlen + 1);
-
-    state->gai_request = (struct gaicb) {
-        .ar_name = state->address,
-        .ar_service = NULL,
-        .ar_request = &state->hint,
-        .ar_result = NULL
-    };
-    state->gai_requests = &state->gai_request;
-    state->sigevent = (struct sigevent) {
-        .sigev_notify = SIGEV_THREAD,
-        .sigev_value = {
-            .sival_ptr = state
-        },
-        .sigev_notify_function = GetHostEntryForNameAsyncComplete
-    };
-    state->entry = entry;
-    state->callback = callback;
-
-    atomic_thread_fence(memory_order_release);
-
-    int32_t result = getaddrinfo_a(GAI_NOWAIT, &state->gai_requests, 1, &state->sigevent);
-
-    if (result != 0)
-    {
-        free(state);
-        return ConvertGetAddrInfoAndGetNameInfoErrorsToPal(result);
-    }
-
-    return result;
-#else
-    (void)address;
-    (void)addressFamily;
-    (void)entry;
-    (void)callback;
-
-    // GetHostEntryForNameAsync is not supported on this platform.
-    return -1;
-#endif
-}
-
 void SystemNative_FreeHostEntry(HostEntry* entry)
 {
     if (entry != NULL)

src/libraries/Native/Unix/System.Native/pal_networking.h

@@ -301,16 +301,8 @@ typedef struct
     uint32_t Padding;    // Pad out to 8-byte alignment
 } SocketEvent;
 
-PALEXPORT int32_t SystemNative_PlatformSupportsGetAddrInfoAsync(void);
-
 PALEXPORT int32_t SystemNative_GetHostEntryForName(const uint8_t* address, int32_t addressFamily, HostEntry* entry);
 
-typedef void (*GetHostEntryForNameCallback)(HostEntry* entry, int status);
-PALEXPORT int32_t SystemNative_GetHostEntryForNameAsync(const uint8_t* address,
-                                                        int32_t addressFamily,
-                                                        HostEntry* entry,
-                                                        GetHostEntryForNameCallback callback);
-
 PALEXPORT void SystemNative_FreeHostEntry(HostEntry* entry);
 
 

src/libraries/Native/Unix/configure.cmake

@@ -6,7 +6,6 @@ include(CheckPrototypeDefinition)
 include(CheckStructHasMember)
 include(CheckSymbolExists)
 include(CheckTypeSize)
-include(CMakePushCheckState)
 include(CheckLibraryExists)
 
 # CMP0075 Include file check macros honor CMAKE_REQUIRED_LIBRARIES.
@@ -918,19 +917,6 @@ check_symbol_exists(
     HAVE_INOTIFY_RM_WATCH)
 set (CMAKE_REQUIRED_LIBRARIES ${PREVIOUS_CMAKE_REQUIRED_LIBRARIES})
 
-if (CLR_CMAKE_TARGET_LINUX)
-    cmake_push_check_state(RESET)
-    set (CMAKE_REQUIRED_DEFINITIONS "-D_GNU_SOURCE")
-    set (CMAKE_REQUIRED_LIBRARIES "-lanl")
-
-    check_symbol_exists(
-        getaddrinfo_a
-        netdb.h
-        HAVE_GETADDRINFO_A)
-
-    cmake_pop_check_state()
-endif ()
-
 set (HAVE_INOTIFY 0)
 if (HAVE_INOTIFY_INIT AND HAVE_INOTIFY_ADD_WATCH AND HAVE_INOTIFY_RM_WATCH)
     set (HAVE_INOTIFY 1)

src/libraries/System.Net.NameResolution/src/System/Net/Dns.cs

@@ -547,6 +547,8 @@ private static Task GetHostEntryOrAddressesCoreAsync(string hostName, bool justR
             {
                 if (NameResolutionPal.SupportsGetAddrInfoAsync)
                 {
+#pragma warning disable CS0162 // Unreachable code detected -- SupportsGetAddrInfoAsync is a constant on *nix.
+
                     // If the OS supports it and 'hostName' is not an IP Address, resolve the name asynchronously
                     // instead of calling the synchronous version in the ThreadPool.
                     // If it fails, we will fall back to ThreadPool as well.
@@ -571,6 +573,7 @@ private static Task GetHostEntryOrAddressesCoreAsync(string hostName, bool justR
                     {
                         return t;
                     }
+#pragma warning restore CS0162
                 }
 
                 asyncState = family == AddressFamily.Unspecified ? (object)hostName : new KeyValuePair<string, AddressFamily>(hostName, family);