add pop function in FIFOBuff

FIFOBuff/FIFOBuffChar.c

@@ -122,6 +122,34 @@ bool FIFOBuffChar_get(FIFOBuffChar_t *fifo, char *p) // Change the function para
     return ok;
 }
 
+bool FIFOBuffChar_pop(FIFOBuffChar_t *fifo)
+{
+    bool ok = true;
+
+    if (fifo->FirstEl_p == NULL)
+    { // buffer is empty
+        ok = false;
+    }
+    else
+    { // there is data in the buffer
+        // find the second last element
+        FIFOBuffChar_element_t* secondLastEl; = fifo->FirstEl_p;
+        while (secondLastEl->nextElement != fifo->LastEl_p)
+        {
+            secondLastEl = secondLastEl->nextElement;
+        }
+
+        // remove last element
+        free(fifo->LastEl_p);
+
+        // update chain
+        secondLastEl->nextElement == NULL;
+        fifo->LastEl_p = secondLastEl;
+    }
+
+    return ok;
+}
+
 bool FIFOBuffChar_is_full(FIFOBuffChar_t *fifo)
 {
     return fifo->full;

FIFOBuff/FIFOBuffChar.h

@@ -32,7 +32,10 @@ extern bool FIFOBuffChar_put(FIFOBuffChar_t *fifo, char i);
 
 // get value from buffer and writes it to *p if buffer not empty
 // returns true on success or false otherways
-extern bool FIFOBuffChar_get(FIFOBuffChar_t *fifo, char *p);                    //moet dit "char" zijn of "uint8_t"
+extern bool FIFOBuffChar_get(FIFOBuffChar_t *fifo, char *p);
+
+// pop last added value from the buffer
+extern bool FIFOBuffChar_pop(FIFOBuffChar_t *fifo);
 
 // returns false if last put fails to gain memory and no get is called afterwards or true otherwise
 extern bool FIFOBuffChar_is_full(FIFOBuffChar_t *fifo);