Diff: queue.cpp

Revision:

0:a03810d46457

Child:

1:2670ac23765f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/queue.cpp	Fri Oct 22 22:07:25 2010 +0000
@@ -0,0 +1,185 @@
+/* mbed queue Library
+ * Copyright (c) 2010 William Basser ( wbasser [at] gmail [dot] com )
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+// inlcude the defs
+#include "queue.h"
+
+// construction 
+Queue::Queue( int iSize, int iCount )
+{
+    // allocate space for the queue
+    if (( m_pnHead = ( unsigned char* )malloc( iSize * iCount )) != NULL )
+    {
+        // set the tail/clear the indices/set the size and length
+        m_pnTail     = m_pnHead + ( iSize * iCount );
+        m_iSize     = iSize;
+        m_iCount     = iCount;
+        m_pnRdIndex    = m_pnHead;
+        m_pnWrIndex    = m_pnHead;
+        m_iLclCount    = 0;
+    }
+}
+
+// destruction
+Queue::~Queue( )
+{
+    // free the memory
+    free( m_pnHead );
+}
+
+// put an item into the queue
+bool Queue::Put( void* pvItem )
+{
+    bool bResult = false;
+    
+    // check for room
+    if ( m_iLclCount < m_iCount )
+    {
+        __disable_irq( );
+        // copy the item/adjust the pointer/check for overflow
+        memcpy( m_pnWrIndex, pvItem, m_iSize );
+        m_pnWrIndex += m_iSize;
+        if ( m_pnWrIndex >= m_pnTail )
+            m_pnWrIndex = m_pnHead;
+
+        // increment the count
+        m_iLclCount++;
+        __enable_irq( );
+
+        // set the result to 0k
+        bResult = true;
+    }
+
+    // return the status
+    return( bResult );
+}
+
+// get an item from the queue
+bool Queue::Get( void* pvItem )
+{
+    bool bResult = false;
+    
+    // check for room
+    if ( m_iLclCount != 0 )
+    {
+        __disable_irq( );
+        // copy the item/adjust the pointer/check for overflow
+        memcpy( pvItem, m_pnRdIndex, m_iSize );
+        m_pnRdIndex += m_iSize;
+        if ( m_pnRdIndex >= m_pnTail )
+            m_pnRdIndex = m_pnHead;
+
+        // decrement the count
+        m_iLclCount--;
+        __enable_irq( );
+        // set the result to 0k
+        bResult = true;
+    }
+
+    // return the status
+    return( bResult );
+}
+
+// put an item into the queue
+bool Queue::PutIrq( void* pvItem )
+{
+    bool bResult = false;
+    
+    // check for room
+    if ( m_iLclCount < m_iCount )
+    {
+        // copy the item/adjust the pointer/check for overflow
+        memcpy( m_pnWrIndex, pvItem, m_iSize );
+        m_pnWrIndex += m_iSize;
+        if ( m_pnWrIndex >= m_pnTail )
+            m_pnWrIndex = m_pnHead;
+
+        // increment the count
+        m_iLclCount++;
+
+        // set the result to 0k
+        bResult = true;
+    }
+
+    // return the status
+    return( bResult );
+}
+
+// get an item from the queue
+bool Queue::GetIrq( void* pvItem )
+{
+    bool bResult = false;
+    
+    // check for room
+    if ( m_iLclCount != 0 )
+    {
+        // copy the item/adjust the pointer/check for overflow
+        memcpy( pvItem, m_pnRdIndex, m_iSize );
+        m_pnRdIndex += m_iSize;
+        if ( m_pnRdIndex >= m_pnTail )
+            m_pnRdIndex = m_pnHead;
+
+        // decrement the count
+        m_iLclCount--;
+
+        // set the result to 0k
+        bResult = true;
+    }
+
+    // return the status
+    return( bResult );
+}
+
+// get the number of items in the queue
+int Queue::GetNumberOfItems( void )
+{
+    // return the count
+    return( m_iLclCount );
+}
+
+// peeks at the item at the top of the queue
+bool Queue::Peek( void* pvItem )
+{
+    bool bResult = false;
+    
+    // check for room
+    if ( m_iLclCount != 0 )
+    {
+        // copy the item
+        memcpy( pvItem, m_pnRdIndex, m_iSize );
+
+        // set the result to 0k
+        bResult = true;
+    }
+
+    // return the status
+    return( bResult );
+}
+
+// flush all items from the queue
+void Queue::Flush( void )
+{
+    // reset the indices
+    m_iLclCount = 0;
+    m_pnRdIndex = m_pnWrIndex = m_pnHead;
+}
+