sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

MdeModulePkg: TerminalDxe: avoid checking uninitialized variable

Browse Source 
The SerialIo->GetControl() function is not required to set the
Control output parameter on error. Make sure we apply the
EFI_SERIAL_INPUT_BUFFER_EMPTY optimization in
TerminalConInTimerHandler() only if the SerialIo->GetControl()
function call set that bit in the Control variable.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18962 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Star Zeng 2015-11-26 08:46:20 +00:00 committed by lzeng14
parent 1b96428d92
commit d9b51b21e7
1 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
View File

@ -2,7 +2,7 @@
Implementation for EFI_SIMPLE_TEXT_INPUT_PROTOCOL protocol. Implementation for EFI_SIMPLE_TEXT_INPUT_PROTOCOL protocol.
(C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR> (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR> Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at which accompanies this distribution. The full text of the license may be found at
@ -562,10 +562,11 @@ TerminalConInTimerHandler (
} }
// //
// Check whether serial buffer is empty. // Check whether serial buffer is empty.
// Skip the key transfer loop only if the SerialIo protocol instance
// successfully reports EFI_SERIAL_INPUT_BUFFER_EMPTY.
// //
Status = SerialIo->GetControl (SerialIo, &Control); Status = SerialIo->GetControl (SerialIo, &Control);
if (EFI_ERROR (Status) || ((Control & EFI_SERIAL_INPUT_BUFFER_EMPTY) == 0)) {
if ((Control & EFI_SERIAL_INPUT_BUFFER_EMPTY) == 0) {
// //
// Fetch all the keys in the serial buffer, // Fetch all the keys in the serial buffer,
// and insert the byte stream into RawFIFO. // and insert the byte stream into RawFIFO.