[reactos] 05/06: [WIN32SS:ENG] Add EngpLinkGraphicsDevice, to add a device to gpGraphicsDeviceFirst list

[Hervé Poussineau]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=b3cdb7e713da0801b6af5…

commit b3cdb7e713da0801b6af5c6ddafcdfc1fb3aac8e
Author:     Hervé Poussineau <hpoussin(a)reactos.org>
AuthorDate: Thu Nov 10 22:11:22 2022 +0100
Commit:     Hervé Poussineau <hpoussin(a)reactos.org>
CommitDate: Tue Nov 15 23:16:10 2022 +0100

    [WIN32SS:ENG] Add EngpLinkGraphicsDevice, to add a device to gpGraphicsDeviceFirst
list
---
 win32ss/gdi/eng/device.c | 37 +++++++++++++++++++++++++++++++------
 1 file changed, 31 insertions(+), 6 deletions(-)

diff --git a/win32ss/gdi/eng/device.c b/win32ss/gdi/eng/device.c
index 8a0d686d2ea..1e2a46a0a17 100644
--- a/win32ss/gdi/eng/device.c
+++ b/win32ss/gdi/eng/device.c
@@ -98,6 +98,36 @@ EngpHasVgaDriver(
     return (_wcsnicmp(awcServiceName, L"VGA", 3) == 0);
 }
 
+/*
+ * Add a device to gpGraphicsDeviceFirst/gpGraphicsDeviceLast list (if not already
present).
+ */
+_Requires_lock_held_(ghsemGraphicsDeviceList)
+static
+VOID
+EngpLinkGraphicsDevice(
+    _In_ PGRAPHICS_DEVICE pToAdd)
+{
+    PGRAPHICS_DEVICE pGraphicsDevice;
+
+    TRACE("EngLinkGraphicsDevice(%p)\n", pToAdd);
+
+    /* Search if device is not already linked */
+    for (pGraphicsDevice = gpGraphicsDeviceFirst;
+         pGraphicsDevice;
+         pGraphicsDevice = pGraphicsDevice->pNextGraphicsDevice)
+    {
+        if (pGraphicsDevice == pToAdd)
+            return;
+    }
+
+    pToAdd->pNextGraphicsDevice = NULL;
+    if (gpGraphicsDeviceLast)
+        gpGraphicsDeviceLast->pNextGraphicsDevice = pToAdd;
+    gpGraphicsDeviceLast = pToAdd;
+    if (!gpGraphicsDeviceFirst)
+        gpGraphicsDeviceFirst = pToAdd;
+}
+
 /*
  * Remove a device from gpGraphicsDeviceFirst/gpGraphicsDeviceLast list.
  */
@@ -567,12 +597,7 @@ EngpRegisterGraphicsDevice(
     EngAcquireSemaphore(ghsemGraphicsDeviceList);
 
     /* Insert the device into the global list */
-    pGraphicsDevice->pNextGraphicsDevice = NULL;
-    if (gpGraphicsDeviceLast)
-        gpGraphicsDeviceLast->pNextGraphicsDevice = pGraphicsDevice;
-    gpGraphicsDeviceLast = pGraphicsDevice;
-    if (!gpGraphicsDeviceFirst)
-        gpGraphicsDeviceFirst = pGraphicsDevice;
+    EngpLinkGraphicsDevice(pGraphicsDevice);
 
     /* Increment the device number */
     giDevNum++;