Diploma Thesis in Aerospace Engineering, January 2014

Diff: MODSERIAL/RESIZE.cpp

Revision:

0:1447d2f773db

diff -r 000000000000 -r 1447d2f773db MODSERIAL/RESIZE.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MODSERIAL/RESIZE.cpp	Wed Jul 09 07:35:50 2014 +0000
@@ -0,0 +1,123 @@
+/*
+    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)
+{
+    int rval = Ok;
+    
+    // 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) return rval;
+    
+    // Make sure the ISR cannot use the buffers while we are manipulating them.
+    disableIrq();
+    
+    // If the requested buffer size is larger than the current size, 
+    // attempt to create a new buffer and use it.
+    if (buffer_size[type] < size) {
+        rval = upSizeBuffer(size, type, memory_check);
+    }
+    else if (buffer_size[type] > size) {
+        rval = downSizeBuffer(size, type, memory_check);
+    }
+    
+    // Start the ISR system again with the new buffers.
+    enableIrq();
+    
+    return rval;
+}
+
+int 
+MODSERIAL::downSizeBuffer(int size, IrqType type, bool memory_check)
+{
+    if (size >= buffer_count[type]) {
+        return BufferOversize;
+    }
+    
+    char *s = (char *)malloc(size);
+    
+    if (s == (char *)NULL) {
+        if (memory_check) {
+            error("Failed to allocate memory for %s buffer", type == TxIrq ? "TX" : "RX");
+        }
+        return NoMemory;
+    }
+    
+    int c, new_in = 0;
+    
+    do {
+        c = __getc(false);
+        if (c != -1) s[new_in++] = (char)c;
+        if (new_in >= size) new_in = 0;
+    }
+    while (c != -1);
+    
+    free((char *)buffer[type]);
+    buffer[type]      = s;
+    buffer_in[type]   = new_in;
+    buffer_out[type]  = 0;
+    return Ok;        
+}
+
+int 
+MODSERIAL::upSizeBuffer(int size, IrqType type, bool memory_check)
+{
+    char *s = (char *)malloc(size);
+    
+    if (s == (char *)NULL) {
+        if (memory_check) {
+            error("Failed to allocate memory for %s buffer", type == TxIrq ? "TX" : "RX");
+        }
+        return NoMemory;
+    }
+    
+    if (buffer_count[type] == 0) { // Current buffer empty?
+        free((char *)buffer[type]);
+        buffer[type]      = s;
+        buffer_in[type]   = 0;
+        buffer_out[type]  = 0;
+    }        
+    else { // Copy the current contents into the new buffer.
+        int c, new_in = 0;
+        do {
+            c = __getc(false);
+            if (c != -1) s[new_in++] = (char)c;
+            if (new_in >= size) new_in = 0; // Shouldn't happen, but be sure.
+        }
+        while (c != -1);
+        free((char *)buffer[type]);
+        buffer[type]      = s;
+        buffer_in[type]   = new_in;
+        buffer_out[type]  = 0;
+    }
+    
+    buffer_size[type] = size;
+    return Ok;
+}
+
+}; // namespace AjK ends