Diff: WNCInterface/WncControllerK64F/MODSERIAL/RESIZE.cpp

Revision:

15:6f2798e45099

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WNCInterface/WncControllerK64F/MODSERIAL/RESIZE.cpp	Thu Dec 01 18:05:38 2016 +0000
@@ -0,0 +1,97 @@
+/*
+    Copyright (c) 2010 Andy Kirkham
+ 
+    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.
+*/
+
+#include "MODSERIAL.h"
+#include "MACROS.h"
+
+namespace AjK {
+
+int
+MODSERIAL::resizeBuffer(int size, IrqType type, bool memory_check)
+{    
+    // Make sure the ISR cannot use the buffers while we are manipulating them.
+    NVIC_DisableIRQ(_IRQ);
+    
+    // If the requested size is the same as the current size there's nothing to do,
+    // just continue to use the same buffer as it's fine as it is.
+    if (buffer_size[type] == size)
+    {
+        NVIC_EnableIRQ(_IRQ);  
+        return Ok;
+    }
+    
+    // is new buffer is big enough?
+    if (size <= buffer_count[type])
+    {
+        NVIC_EnableIRQ(_IRQ);  
+        return BufferOversize;
+    }
+    
+    // allocate new buffer
+    char * newBuffer = (char*)malloc(size);
+    
+    // allocation failed?
+    if (newBuffer == (char*)NULL)
+    {
+        if (memory_check)
+            error("Failed to allocate memory for %s buffer", type == TxIrq ? "TX" : "RX");
+            
+        return NoMemory;
+    }
+    
+    // copy old buffer content to new one
+    moveRingBuffer(newBuffer, type);
+    
+    // free old buffer and reset ring buffer cursor
+    free((char*)buffer[type]);
+        
+    buffer[type]      = newBuffer;
+    buffer_size[type] = size;
+    buffer_in[type]   = buffer_count[type];
+    buffer_out[type]  = 0;    
+    
+    // Start the ISR system again with the new buffers.
+    NVIC_EnableIRQ(_IRQ);    
+    return Ok;
+}
+
+void MODSERIAL::moveRingBuffer(char * newBuffer, IrqType type)
+{   
+    // copy old buffer content to new one
+    if(buffer_in[type] > buffer_out[type])      
+    {   // content in the middle of the ring buffer
+        memcpy(&newBuffer[0], (char*)&buffer[type][buffer_out[type]], buffer_count[type]);
+    }  
+    else if(buffer_in[type] < buffer_out[type]) 
+    {   // content split, free space in the middle
+        // copy last part of the old buffer
+        int end_count= buffer_size[type] - buffer_out[type];
+        memcpy(&newBuffer[0], (char*)&buffer[type][buffer_out[type]], end_count);
+        
+        // copy first part of old buffer
+        memcpy(&newBuffer[end_count], (char*)buffer[type], buffer_in[type]);
+    }
+    // else old buffer empty
+}
+
+}; // namespace AjK ends
+