From c6f01e113d244a0c7ab22a3c4f1bab55693dd011 Mon Sep 17 00:00:00 2001
From: Lars Op den Kamp <lars@opdenkamp.eu>
Date: Fri, 1 Jun 2012 00:30:07 +0200
Subject: [PATCH] cec: hold a lock when changing the ackmask in
 CUSBCECAdapterCommunication::Open

---
 src/lib/CECProcessor.cpp                      |  3 --
 .../adapter/USBCECAdapterCommunication.cpp    | 30 ++++++++++++-------
 src/lib/adapter/USBCECAdapterCommunication.h  |  5 ++++
 3 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/src/lib/CECProcessor.cpp b/src/lib/CECProcessor.cpp
index fe40990..0012a53 100644
--- a/src/lib/CECProcessor.cpp
+++ b/src/lib/CECProcessor.cpp
@@ -148,9 +148,6 @@ bool CCECProcessor::OpenConnection(const char *strPort, uint16_t iBaudRate, uint
 
   m_libcec->AddLog(CEC_LOG_NOTICE, "connection opened");
 
-  // always start by setting the ackmask to 0, to clear previous values
-  SetAckMask(0);
-
   // mark as initialised
   SetCECInitialised(true);
 
diff --git a/src/lib/adapter/USBCECAdapterCommunication.cpp b/src/lib/adapter/USBCECAdapterCommunication.cpp
index 33eb260..d6d9b5c 100644
--- a/src/lib/adapter/USBCECAdapterCommunication.cpp
+++ b/src/lib/adapter/USBCECAdapterCommunication.cpp
@@ -66,6 +66,7 @@ CUSBCECAdapterCommunication::CUSBCECAdapterCommunication(IAdapterCommunicationCa
   for (unsigned int iPtr = CECDEVICE_TV; iPtr < CECDEVICE_BROADCAST; iPtr++)
     m_bWaitingForAck[iPtr] = false;
   m_port = new CSerialPort(strPort, iBaudRate);
+  m_commands = new CUSBCECAdapterCommands(this);
 }
 
 CUSBCECAdapterCommunication::~CUSBCECAdapterCommunication(void)
@@ -76,6 +77,13 @@ CUSBCECAdapterCommunication::~CUSBCECAdapterCommunication(void)
   DELETE_AND_NULL(m_port);
 }
 
+void CUSBCECAdapterCommunication::ResetMessageQueue(void)
+{
+  DELETE_AND_NULL(m_adapterMessageQueue);
+  m_adapterMessageQueue = new CCECAdapterMessageQueue(this);
+  m_adapterMessageQueue->CreateThread();
+}
+
 bool CUSBCECAdapterCommunication::Open(uint32_t iTimeoutMs /* = CEC_DEFAULT_CONNECT_TIMEOUT */, bool bSkipChecks /* = false */, bool bStartListening /* = true */)
 {
   bool bConnectionOpened(false);
@@ -96,15 +104,7 @@ bool CUSBCECAdapterCommunication::Open(uint32_t iTimeoutMs /* = CEC_DEFAULT_CONN
       return true;
     }
 
-    /* adapter commands */
-    if (!m_commands)
-      m_commands = new CUSBCECAdapterCommands(this);
-
-    if (!m_adapterMessageQueue)
-    {
-      m_adapterMessageQueue = new CCECAdapterMessageQueue(this);
-      m_adapterMessageQueue->CreateThread();
-    }
+    ResetMessageQueue();
 
     /* try to open the connection */
     CStdString strError;
@@ -145,6 +145,9 @@ bool CUSBCECAdapterCommunication::Open(uint32_t iTimeoutMs /* = CEC_DEFAULT_CONN
     ClearInputBytes();
   }
 
+  // always start by setting the ackmask to 0, to clear previous values
+  SetAckMask(0);
+
   if (!CreateThread())
   {
     bConnectionOpened = false;
@@ -493,11 +496,15 @@ bool CUSBCECAdapterCommunication::StartBootloader(void)
 
 bool CUSBCECAdapterCommunication::SetAckMask(uint16_t iMask)
 {
-  if (m_iAckMask == iMask)
-    return true;
+  {
+    CLockObject lock(m_mutex);
+    if (m_iAckMask == iMask)
+      return true;
+  }
 
   if (IsOpen() && m_commands->SetAckMask(iMask))
   {
+    CLockObject lock(m_mutex);
     m_iAckMask = iMask;
     return true;
   }
@@ -508,6 +515,7 @@ bool CUSBCECAdapterCommunication::SetAckMask(uint16_t iMask)
 
 uint16_t CUSBCECAdapterCommunication::GetAckMask(void)
 {
+  CLockObject lock(m_mutex);
   return m_iAckMask;
 }
 
diff --git a/src/lib/adapter/USBCECAdapterCommunication.h b/src/lib/adapter/USBCECAdapterCommunication.h
index 7409e86..0177f08 100644
--- a/src/lib/adapter/USBCECAdapterCommunication.h
+++ b/src/lib/adapter/USBCECAdapterCommunication.h
@@ -157,6 +157,11 @@ namespace CEC
      */
     void MarkAsWaiting(const cec_logical_address dest);
 
+    /*!
+     * @brief Clear and reset the message queue.
+     */
+    void ResetMessageQueue(void);
+
     PLATFORM::ISocket *                          m_port;                 /**< the com port connection */
     PLATFORM::CMutex                             m_mutex;                /**< mutex for changes in this class */
     uint8_t                                      m_iLineTimeout;         /**< the current line timeout on the CEC line */
-- 
2.34.1