[PATCH 3/6] winhttp: Use the thread pool for asynchronous hostname resolution.

[Hans Leidekker]

Signed-off-by: Hans Leidekker 
---
 dlls/winhttp/net.c | 46 ++++++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/dlls/winhttp/net.c b/dlls/winhttp/net.c
index af1d19d212..a1ad0461d4 100644
--- a/dlls/winhttp/net.c
+++ b/dlls/winhttp/net.c
@@ -651,42 +651,44 @@ static DWORD resolve_hostname( const WCHAR *name, INTERNET_PORT port, struct soc
     return ERROR_SUCCESS;
 }

-struct resolve_args
+struct async_resolve
 {
     const WCHAR             *hostname;
     INTERNET_PORT            port;
-    struct sockaddr_storage *sa;
+    struct sockaddr_storage *addr;
+    DWORD                    result;
+    HANDLE                   done;
 };

-static DWORD CALLBACK resolve_proc( LPVOID arg )
+static void CALLBACK resolve_proc( TP_CALLBACK_INSTANCE *instance, void *ctx )
 {
-    struct resolve_args *ra = arg;
-    return resolve_hostname( ra->hostname, ra->port, ra->sa );
+    struct async_resolve *async = ctx;
+    async->result = resolve_hostname( async->hostname, async->port, async->addr );
+    SetEvent( async->done );
 }

-BOOL netconn_resolve( WCHAR *hostname, INTERNET_PORT port, struct sockaddr_storage *sa, int timeout )
+BOOL netconn_resolve( WCHAR *hostname, INTERNET_PORT port, struct sockaddr_storage *addr, int timeout )
 {
     DWORD ret;

-    if (timeout)
+    if (!timeout) ret = resolve_hostname( hostname, port, addr );
+    else
     {
-        DWORD status;
-        HANDLE thread;
-        struct resolve_args ra;
-
-        ra.hostname = hostname;
-        ra.port     = port;
-        ra.sa       = sa;
-
-        thread = CreateThread( NULL, 0, resolve_proc, &ra, 0, NULL );
-        if (!thread) return FALSE;
+        struct async_resolve async;

-        status = WaitForSingleObject( thread, timeout );
-        if (status == WAIT_OBJECT_0) GetExitCodeThread( thread, &ret );
-        else ret = ERROR_WINHTTP_TIMEOUT;
-        CloseHandle( thread );
+        async.hostname = hostname;
+        async.port     = port;
+        async.addr     = addr;
+        if (!(async.done = CreateEventW( NULL, FALSE, FALSE, NULL ))) return FALSE;
+        if (!TrySubmitThreadpoolCallback( resolve_proc, &async, NULL ))
+        {
+            CloseHandle( async.done );
+            return FALSE;
+        }
+        if (WaitForSingleObject( async.done, timeout ) != WAIT_OBJECT_0) ret = ERROR_WINHTTP_TIMEOUT;
+        else ret = async.result;
+        CloseHandle( async.done );
     }
-    else ret = resolve_hostname( hostname, port, sa );

if (ret)
     {

[Jacek Caban]

Hi Hans,

On 11/23/18 11:35 AM, Hans Leidekker wrote:
> -
>    DWORD status;
> -
>    HANDLE thread;
> -
>    struct resolve_args ra;
> -
> -
>    ra.hostname = hostname;
> -
>    ra.port     = port;
> -
>    ra.sa       = sa;
> -
> -
>    thread = CreateThread( NULL, 0, resolve_proc, &ra, 0, NULL );
> -
>    if (!thread) return FALSE;
> -
>    struct async_resolve async;
>
> -
>    status = WaitForSingleObject( thread, timeout );
> -
>    if (status == WAIT_OBJECT_0) GetExitCodeThread( thread, &ret );
> -
>    else ret = ERROR_WINHTTP_TIMEOUT;
> -
>    CloseHandle( thread );
> -
>    async.hostname = hostname;
> -
>    async.port     = port;
> -
>    async.addr     = addr;
> -
>    if (!(async.done = CreateEventW( NULL, FALSE, FALSE, NULL ))) return FALSE;
> -
>    if (!TrySubmitThreadpoolCallback( resolve_proc, &async, NULL ))

The patch looks good to me, but note that we could consider just using 
GetAddrInfoEx instead (although it doesn't support timeout yet).

Jacek