[aandrejevic] 60526: [NTVDM] Properly handle the case when the console framebuffer could not be created.

Author: aandrejevic
Date: Fri Oct  4 21:16:58 2013
New Revision: 60526

URL: http://svn.reactos.org/svn/reactos?rev=60526&view=rev
Log:
[NTVDM]
Properly handle the case when the console framebuffer could not be created.

Modified:
    branches/ntvdm/subsystems/ntvdm/vga.c

Modified: branches/ntvdm/subsystems/ntvdm/vga.c
URL: http://svn.reactos.org/svn/reactos/branches/ntvdm/subsystems/ntvdm/vga.c?rev...
==============================================================================
--- branches/ntvdm/subsystems/ntvdm/vga.c	[iso-8859-1] (original)
+++ branches/ntvdm/subsystems/ntvdm/vga.c	[iso-8859-1] Fri Oct  4 21:16:58 2013
@@ -488,12 +488,22 @@
     if (!(VgaGcRegisters[VGA_GC_MISC_REG] & VGA_GC_MISC_NOALPHA))
     {
         /* Enter new text mode */
-        if (!VgaEnterTextMode(&Resolution)) return;
+        if (!VgaEnterTextMode(&Resolution))
+        {
+            DisplayMessage(L"An unexpected VGA error occurred while switching into text mode.");
+            VdmRunning = FALSE;
+            return;
+        }
     }
     else
     {
         /* Enter 8-bit graphics mode */
-        if (!VgaEnterGraphicsMode(&Resolution)) return;
+        if (!VgaEnterGraphicsMode(&Resolution))
+        {
+            DisplayMessage(L"An unexpected VGA error occurred while switching into graphics mode.");
+            VdmRunning = FALSE;
+            return;
+        }
     }

/* Trigger a full update of the screen */
@@ -515,6 +525,12 @@
     DWORD Address = (VgaCrtcRegisters[VGA_CRTC_START_ADDR_HIGH_REG] << 8)
                     + VgaCrtcRegisters[VGA_CRTC_START_ADDR_LOW_REG];
     DWORD ScanlineSize = (DWORD)VgaCrtcRegisters[VGA_CRTC_OFFSET_REG] * 2;
+
+    /*
+     * If console framebuffer is NULL, that means something went wrong
+     * earlier and this is the final display refresh.
+     */
+    if (ConsoleFramebuffer == NULL) return;

/* Check if this is text mode or graphics mode */
     if (VgaGcRegisters[VGA_GC_MISC_REG] & VGA_GC_MISC_NOALPHA)