[reactos] 02/02: [WIN32K] Check if a graphics device already exists before trying to add it

[Timo Kreuzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=77e891b8ab93dda5c1a42…

commit 77e891b8ab93dda5c1a4264df4427dc99163ac8a
Author:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
AuthorDate: Tue Jul 13 22:24:41 2021 +0200
Commit:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
CommitDate: Thu Jul 15 08:32:46 2021 +0200

    [WIN32K] Check if a graphics device already exists before trying to add it
    
    This avoids DPRINTs alleging a failure to open a device.
    Also improve another DPRINT.
---
 win32ss/gdi/eng/device.c      | 9 +++++++++
 win32ss/user/ntuser/display.c | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/win32ss/gdi/eng/device.c b/win32ss/gdi/eng/device.c
index deca6e7a9ff..12fbcd0359b 100644
--- a/win32ss/gdi/eng/device.c
+++ b/win32ss/gdi/eng/device.c
@@ -37,6 +37,7 @@ EngpUpdateGraphicsDeviceList(VOID)
 {
     ULONG iDevNum, iVGACompatible = -1, ulMaxObjectNumber = 0;
     WCHAR awcDeviceName[20];
+    UNICODE_STRING ustrDeviceName;
     WCHAR awcBuffer[256];
     NTSTATUS Status;
     PGRAPHICS_DEVICE pGraphicsDevice;
@@ -73,6 +74,14 @@ EngpUpdateGraphicsDeviceList(VOID)
     {
         /* Create the adapter's key name */
         swprintf(awcDeviceName, L"\\Device\\Video%lu", iDevNum);
+        RtlInitUnicodeString(&ustrDeviceName, awcDeviceName);
+
+        /* Check if the device exists already */
+        pGraphicsDevice = EngpFindGraphicsDevice(&ustrDeviceName, iDevNum, 0);
+        if (pGraphicsDevice != NULL)
+        {
+            continue;
+        }
 
         /* Read the reg key name */
         cbValue = sizeof(awcBuffer);
diff --git a/win32ss/user/ntuser/display.c b/win32ss/user/ntuser/display.c
index 676b7d0420c..df00c0e3974 100644
--- a/win32ss/user/ntuser/display.c
+++ b/win32ss/user/ntuser/display.c
@@ -257,7 +257,7 @@ UserEnumDisplayDevices(
     if (!pGraphicsDevice)
     {
         /* No device found */
-        ERR("No GRAPHICS_DEVICE found\n");
+        ERR("No GRAPHICS_DEVICE found for '%wZ', iDevNum %lu\n",
pustrDevice, iDevNum);
         return STATUS_UNSUCCESSFUL;
     }