iphlpapi: _res is per-thread in glibc.

dlls/iphlpapi/iphlpapi_main.c

@@ -66,16 +66,13 @@ WINE_DEFAULT_DEBUG_CHANNEL(iphlpapi);
 #define INADDR_NONE ~0UL
 #endif
 
-static int resolver_initialised;
-
 /* call res_init() just once because of a bug in Mac OS X 10.4 */
+/* Call once per thread on systems that have per-thread _res. */
+/* FIXME: should do same fix in dnsapi (or use dnsapi here?) */
 static void initialise_resolver(void)
 {
-    if (!resolver_initialised)
-    {
+    if ((_res.options & RES_INIT) == 0)
         res_init();
-        resolver_initialised = 1;
-    }
 }
 
 BOOL WINAPI DllMain (HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)

dlls/iphlpapi/tests/iphlpapi.c

@@ -765,11 +765,12 @@ GetBestRoute
 IpReleaseAddress
 IpRenewAddress
 */
-static void testWin98Functions(void)
+static DWORD CALLBACK testWin98Functions(void *p)
 {
   testGetInterfaceInfo();
   testGetAdaptersInfo();
   testGetNetworkParams();
+  return 0;
 }
 
 static void testGetPerAdapterInfo(void)
@@ -885,9 +886,16 @@ START_TEST(iphlpapi)
 
   loadIPHlpApi();
   if (hLibrary) {
+    HANDLE thread;
+
     testWin98OnlyFunctions();
     testWinNT4Functions();
-    testWin98Functions();
+
+    /* run testGetXXXX in two threads at once to make sure we don't crash in that case */
+    thread = CreateThread(NULL, 0, testWin98Functions, NULL, 0, NULL);
+    testWin98Functions(NULL);
+    WaitForSingleObject(thread, INFINITE);
+
     testWin2KFunctions();
     test_GetAdaptersAddresses();
     freeIPHlpApi();