From 1fec6e5f77e9d5ef73fd88dee8f5587b7c76f5ed Mon Sep 17 00:00:00 2001
From: Andy CA6JAU <juribeparada@gmail.com>
Date: Mon, 16 Jul 2018 16:04:49 -0400
Subject: [PATCH] Optimizing memory for bit ring buffer

---
 BitRB.cpp | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/BitRB.cpp b/BitRB.cpp
index 0aa8ae5..0260d10 100644
--- a/BitRB.cpp
+++ b/BitRB.cpp
@@ -1,7 +1,7 @@
 /*
 TX fifo control - Copyright (C) KI6ZUM 2015
 Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
-Copyright (C) 2016,2017 by Andy Uribe CA6JAU
+Copyright (C) 2016,2017,2018 by Andy Uribe CA6JAU
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Library General Public
@@ -21,6 +21,11 @@ Boston, MA  02110-1301, USA.
 
 #include "BitRB.h"
 
+const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U};
+
+#define WRITE_BIT1(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
+#define READ_BIT1(p,i)    ((p[(i)>>3] & BIT_MASK_TABLE[(i)&7]) >> (7 - ((i)&7)))
+ 
 CBitRB::CBitRB(uint16_t length) :
 m_length(length),
 m_bits(NULL),
@@ -30,7 +35,7 @@ m_tail(0U),
 m_full(false),
 m_overflow(false)
 {
-  m_bits    = new uint8_t[length];
+  m_bits    = new uint8_t[length / 8U];
   m_control = new uint8_t[length];
 }
 
@@ -68,7 +73,7 @@ bool CBitRB::put(uint8_t bit, uint8_t control)
     return false;
   }
 
-  m_bits[m_head]    = bit;
+  WRITE_BIT1(m_bits, m_head, bit);
   m_control[m_head] = control;
 
   m_head++;
@@ -86,7 +91,7 @@ bool CBitRB::get(uint8_t& bit, uint8_t& control)
   if (m_head == m_tail && !m_full)
     return false;
 
-  bit     = m_bits[m_tail];
+  bit     = READ_BIT1(m_bits, m_tail);
   control = m_control[m_tail];
 
   m_full = false;