[port] Windows XP: try to support threading and event subsystems

CMakeLists.txt

@@ -429,10 +429,13 @@ CHECK_SYMBOL_EXISTS (gettimeofday    "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETTIME
 CHECK_SYMBOL_EXISTS (if_indextoname  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IF_INDEXTONAME)
 CHECK_SYMBOL_EXISTS (if_nametoindex  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IF_NAMETOINDEX)
 CHECK_SYMBOL_EXISTS (GetBestRoute2   "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETBESTROUTE2)
+CHECK_SYMBOL_EXISTS (WSAIoctl        "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_WSAIOCTL)
+CHECK_SYMBOL_EXISTS (GetQueuedCompletionStatusEx  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETQUEUEDCOMPLETIONSTATUSEX)
 CHECK_SYMBOL_EXISTS (ConvertInterfaceIndexToLuid  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_CONVERTINTERFACEINDEXTOLUID)
 CHECK_SYMBOL_EXISTS (ConvertInterfaceLuidToNameA  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_CONVERTINTERFACELUIDTONAMEA)
 CHECK_SYMBOL_EXISTS (NotifyIpInterfaceChange      "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_NOTIFYIPINTERFACECHANGE)
 CHECK_SYMBOL_EXISTS (RegisterWaitForSingleObject  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_REGISTERWAITFORSINGLEOBJECT)
+CHECK_SYMBOL_EXISTS (SetFileCompletionNotificationModes  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_SETFILECOMPLETIONNOTIFICATIONMODES)
 
 
 CHECK_SYMBOL_EXISTS (inet_net_pton   "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_INET_NET_PTON)

appveyor.yml

@@ -30,7 +30,7 @@ environment:
       SKIP_TESTS: no
       MSVC_SETUP_ARG: x86
       MSVC_SETUP_PATH: C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars32.bat
-      CMAKE_EXTRA_OPTIONS: -GNinja -DCARES_BUILD_TESTS=ON -DGTEST_ROOT=C:\projects\googletest -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreadedDebugDLL -DCARES_THREADS=OFF -DCMAKE_C_FLAGS="-D_WIN32_WINNT=0x0501" -DCMAKE_CXX_FLAGS="-D_WIN32_WINNT=0x0501"
+      CMAKE_EXTRA_OPTIONS: -GNinja -DCARES_BUILD_TESTS=ON -DGTEST_ROOT=C:\projects\googletest -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreadedDebugDLL -DCMAKE_C_FLAGS="-D_WIN32_WINNT=0x0501" -DCMAKE_CXX_FLAGS="-D_WIN32_WINNT=0x0501"
       TOOLSDIR: ./build/bin
       TESTDIR: ./build/bin
       BUILD_GOOGLETEST: yes
@@ -82,7 +82,7 @@ environment:
       TOOLSDIR: ./build/bin
       TESTDIR: ./build/bin
       PATH: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32\bin;%PATH%
-      CMAKE_EXTRA_OPTIONS: -DCARES_SHARED=OFF -GNinja -DCARES_BUILD_TESTS=ON -DGTEST_ROOT=C:\projects\googletest -DCARES_THREADS=OFF -DCMAKE_C_FLAGS="-D_WIN32_WINNT=0x0501" -DCMAKE_CXX_FLAGS="-D_WIN32_WINNT=0x0501"
+      CMAKE_EXTRA_OPTIONS: -DCARES_SHARED=OFF -GNinja -DCARES_BUILD_TESTS=ON -DGTEST_ROOT=C:\projects\googletest -DCMAKE_C_FLAGS="-D_WIN32_WINNT=0x0501" -DCMAKE_CXX_FLAGS="-D_WIN32_WINNT=0x0501"
       BUILD_GOOGLETEST: yes
 
 # Disabled until AppVeyor updates their Visual Studio with this patch:

configure.ac

@@ -595,11 +595,14 @@ AC_CHECK_DECL(pipe2,           [AC_DEFINE([HAVE_PIPE2],             1, [Define t
 AC_CHECK_DECL(kqueue,          [AC_DEFINE([HAVE_KQUEUE],            1, [Define to 1 if you have `kqueue`]         )], [], $cares_all_includes)
 AC_CHECK_DECL(epoll_create1,   [AC_DEFINE([HAVE_EPOLL],             1, [Define to 1 if you have `epoll_{create1,ctl,wait}`])], [], $cares_all_includes)
 AC_CHECK_DECL(GetBestRoute2,   [AC_DEFINE([HAVE_GETBESTROUTE2],     1, [Define to 1 if you have `GetBestRoute2`]  )], [], $cares_all_includes)
+AC_CHECK_DECL(GetQueuedCompletionStatusEx, [AC_DEFINE([HAVE_GETQUEUEDCOMPLETIONSTATUSEX], 1, [Define to 1 if you have `GetQueuedCompletionStatusEx`])], [], $cares_all_includes)
 AC_CHECK_DECL(ConvertInterfaceIndexToLuid, [AC_DEFINE([HAVE_CONVERTINTERFACEINDEXTOLUID], 1, [Define to 1 if you have `ConvertInterfaceIndexToLuid`])], [], $cares_all_includes)
 AC_CHECK_DECL(ConvertInterfaceLuidToNameA, [AC_DEFINE([HAVE_CONVERTINTERFACELUIDTONAMEA], 1, [Define to 1 if you have `ConvertInterfaceLuidToNameA`])], [], $cares_all_includes)
 AC_CHECK_DECL(NotifyIpInterfaceChange,     [AC_DEFINE([HAVE_NOTIFYIPINTERFACECHANGE],     1, [Define to 1 if you have `NotifyIpInterfaceChange`]    )], [], $cares_all_includes)
 AC_CHECK_DECL(RegisterWaitForSingleObject, [AC_DEFINE([HAVE_REGISTERWAITFORSINGLEOBJECT], 1, [Define to 1 if you have `RegisterWaitForSingleObject`])], [], $cares_all_includes)
 AC_CHECK_DECL(__system_property_get,       [AC_DEFINE([HAVE___SYSTEM_PROPERTY_GET],       1, [Define to 1 if you have `__system_property_get`]      )], [], $cares_all_includes)
+AC_CHECK_DECL(SetFileCompletionNotificationModes, [AC_DEFINE([HAVE_SETFILECOMPLETIONNOTIFICATIONMODES], 1, [Define to 1 if you have `SetFileCompletionNotificationModes`])], [], $cares_all_includes)
+AC_CHECK_DECL(WSAIoctl, [AC_DEFINE([HAVE_WSAIoctl], 1, [Define to 1 if you have `WSAIoctl`])], [], $cares_all_includes)
 
 
 dnl ###############################################################################

src/lib/ares_config.h.cmake

@@ -148,6 +148,12 @@
 /* Define to 1 if you have the `GetBestRoute2' function. */
 #cmakedefine HAVE_GETBESTROUTE2 1
 
+/* Define to 1 if you have the `WSAIoctl' function. */
+#cmakedefine HAVE_WSAIOCTL 1
+
+/* Define to 1 if you have the `GetQueuedCompletionStatusEx' function. */
+#cmakedefine HAVE_GETQUEUEDCOMPLETIONSTATUSEX 1
+
 /* Define to 1 if you have the `ConvertInterfaceIndexToLuid' function. */
 #cmakedefine HAVE_CONVERTINTERFACEINDEXTOLUID 1
 
@@ -160,6 +166,9 @@
 /* Define to 1 if you have the `RegisterWaitForSingleObject' function. */
 #cmakedefine HAVE_REGISTERWAITFORSINGLEOBJECT 1
 
+/* Define to 1 if you have the `SetFileCompletionNotificationModes' function. */
+#cmakedefine HAVE_SETFILECOMPLETIONNOTIFICATIONMODES 1
+
 /* Define to 1 if you have a IPv6 capable working inet_net_pton function. */
 #cmakedefine HAVE_INET_NET_PTON 1
 

src/lib/config-win32.h

@@ -237,10 +237,8 @@
 #  undef HAVE_NETIOAPI_H
 #endif
 
-/* Threading support enabled for Vista+ */
-#if !defined(_WIN32_WINNT) || _WIN32_WINNT >= 0x0600
-#  define CARES_THREADS 1
-#endif
+/* Threading support enabled on Windows always (really XP+ only). */
+#define CARES_THREADS 1
 
 /* ---------------------------------------------------------------- */
 /*                       TYPEDEF REPLACEMENTS                       */
@@ -360,6 +358,15 @@
 /* Define to 1 if you have the `RegisterWaitForSingleObject' function. */
 #define HAVE_REGISTERWAITFORSINGLEOBJECT 1
 
+#if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0600)
+/* Define to 1 if you have the `SetFileCompletionNotificationModes' function. */
+#  define HAVE_SETFILECOMPLETIONNOTIFICATIONMODES 1
+/* Define to 1 if you have the `WSAIoctl' function. */
+#  define HAVE_WSAIOCTL 1
+/* Define to 1 if you have the `GetQueuedCompletionStatusEx' function. */
+#  define HAVE_GETQUEUEDCOMPLETIONSTATUSEX 1
+#endif
+
 #if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0600) && \
   !defined(__WATCOMC__) && !defined(WATT32)
 /* Define if you have if_nametoindex() */

src/lib/event/ares_event_win32.c

@@ -404,10 +404,12 @@ static ares_slist_node_t *ares_afd_handle_create(ares_evsys_win32_t *ew)
     goto fail;
   }
 
+#ifdef HAVE_SETFILECOMPLETIONNOTIFICATIONMODES
   if (!SetFileCompletionNotificationModes(afd->afd_handle,
                                           FILE_SKIP_SET_EVENT_ON_HANDLE)) {
     goto fail;
   }
+#endif
 
   node = ares_slist_insert(ew->afd_handles, afd);
   if (node == NULL) {
@@ -521,6 +523,11 @@ static ares_bool_t ares_evsys_win32_init(ares_event_thread_t *e)
 
 static ares_socket_t ares_evsys_win32_basesocket(ares_socket_t socket)
 {
+#ifndef HAVE_WSAIOCTL
+  /* Assume we don't have an LSP and return the provided socket as the base
+   * socket.  WSAIoctl() isn't supported on Windows XP or below */
+  return socket;
+#else
   while (1) {
     DWORD         bytes; /* Not used */
     ares_socket_t base_socket = ARES_SOCKET_BAD;
@@ -558,6 +565,7 @@ static ares_socket_t ares_evsys_win32_basesocket(ares_socket_t socket)
   }
 
   return socket;
+#endif
 }
 
 static ares_bool_t ares_evsys_win32_afd_enqueue(ares_event_t      *event,
@@ -906,6 +914,46 @@ static ares_bool_t ares_evsys_win32_process_socket_event(
   return ARES_TRUE;
 }
 
+static BOOL ares_GetQueuedCompletionStatusEx(
+  HANDLE CompletionPort,
+  LPOVERLAPPED_ENTRY lpCompletionPortEntries,
+  ULONG ulCount,
+  PULONG ulNumEntriesRemoved,
+  DWORD dwMilliseconds,
+  BOOL fAlertable)
+{
+#ifdef HAVE_GETQUEUEDCOMPLETIONSTATUSEX
+  return GetQueuedCompletionStatusEx(CompletionPort, lpCompletionPortEntries,
+    ulCount, ulNumEntriesRemoved, dwMilliseconds, fAlertable);
+#else
+  ULONG i;
+
+  (void)fAlertable;
+
+  memset(lpCompletionPortEntries, 0,
+         ulCount * sizeof(*lpCompletionPortEntries));
+  (*ulNumEntriesRemoved) = 0;
+
+  for (i=0; i<ulCount; i++) {
+    if (!GetQueuedCompletionStatus(CompletionPort,
+         &lpCompletionPortEntries[i].dwNumberOfBytesTransferred,
+         &lpCompletionPortEntries[i].lpCompletionKey,
+         &lpCompletionPortEntries[i].lpOverlapped,
+         dwMilliseconds)) {
+      break;
+    }
+
+    (*ulNumEntriesRemoved)++;
+  }
+
+  if (*ulNumEntriesRemove > 0) {
+    return TRUE;
+  }
+
+  return FALSE;
+#endif
+}
+
 static size_t ares_evsys_win32_wait(ares_event_thread_t *e,
                                     unsigned long        timeout_ms)
 {
@@ -923,8 +971,9 @@ static size_t ares_evsys_win32_wait(ares_event_thread_t *e,
    * on subsequent attempts, ensure the timeout is 0 */
   do {
     nentries = maxentries;
-    status   = GetQueuedCompletionStatusEx(ew->iocp_handle, entries, nentries,
-                                           &nentries, tout, FALSE);
+    status   = ares_GetQueuedCompletionStatusEx(ew->iocp_handle, entries,
+                                                nentries, &nentries, tout,
+                                                FALSE);
 
     /* Next loop around, we want to return instantly if there are no events to
      * be processed */

src/lib/event/ares_event_win32.h

@@ -156,6 +156,16 @@ typedef NTSTATUS(NTAPI *NtCreateFile_t)(
 #    define HANDLE_FLAG_INHERIT 0x00000001
 #  endif
 
+
+#  if defined(_WIN32_WINNT) && (_WIN32_WINNT < 0x0600)
+typedef struct _OVERLAPPED_ENTRY {
+  ULONG_PTR    lpCompletionKey;
+  LPOVERLAPPED lpOverlapped;
+  ULONG_PTR    Internal;
+  DWORD        dwNumberOfBytesTransferred;
+} OVERLAPPED_ENTRY, *LPOVERLAPPED_ENTRY;
+#  endif
+
 #endif /* _WIN32 */
 
 #endif /* __ARES_EVENT_WIN32_H */