From dcc4520eaae826baf04cd5883ffa721ebe56eb6d Mon Sep 17 00:00:00 2001
From: Zack Grannan <zgrannan@gmail.com>
Date: Sat, 3 May 2014 17:26:21 -0700
Subject: [PATCH] Added BitInputStream + BitOutputStream

---
 BitInputStream.hpp  | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 BitOutputStream.hpp | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 104 insertions(+)
 create mode 100644 BitInputStream.hpp
 create mode 100644 BitOutputStream.hpp

diff --git a/BitInputStream.hpp b/BitInputStream.hpp
new file mode 100644
index 0000000..6d7f73c
--- /dev/null
+++ b/BitInputStream.hpp
@@ -0,0 +1,53 @@
+#ifndef BITINPUTSTREAM_HPP
+#define BITINPUTSTREAM_HPP
+
+#include <iostream>
+#include <bitset>
+
+using namespace std;
+
+/** A class for reading bits (and ints) from an istream
+ */
+class BitInputStream {
+private:
+    istream& in;  // the istream to delegate to
+    char buf;     // the buffer of bits
+  //bitset<8> buf;
+    int bufi;     // the bit buffer index
+
+public:
+  /** Initialize a BitInputStream object, given an istream.
+   */
+  BitInputStream(istream& s) : in(s), buf(0), bufi(8) { }
+  //    BitInputStream(istream& s) : in(s), bufi(8) { }
+
+    /** Read the next bit from the bit buffer.
+     *  If the bit buffer is currently empty,
+     *  fill the bit buffer by reading a char from the istream first.
+     *  Return the bit read as the least signficant bit of an int.
+     *  Return -1 on EOF.
+     *  This must be consistent with BitOutputStream::writeBit(), in terms
+     *  of ordering of bits in the stream.
+     */
+    int readBit();
+
+    /** Read a byte from the ostream.
+     *  Return -1 on EOF.
+     *  This function doesn't touch the bit buffer.
+     *  The client has to manage interaction between reading bits
+     *  and reading bytes.
+     */
+    int readByte();
+
+    /** Read a non-negative int from the ostream.
+     *  Return -1 on EOF.
+     *  This function doesn't touch the bit buffer.
+     *  The client has to manage interaction between reading bits
+     *  and reading ints.
+     */
+    int readInt();
+
+
+};
+
+#endif // BITINPUTSTREAM_HPP
diff --git a/BitOutputStream.hpp b/BitOutputStream.hpp
new file mode 100644
index 0000000..0b1f033
--- /dev/null
+++ b/BitOutputStream.hpp
@@ -0,0 +1,51 @@
+#ifndef BITOUTPUTSTREAM_HPP
+#define BITOUTPUTSTREAM_HPP
+
+#include <iostream>
+#include <bitset>
+
+using namespace std;
+
+/** A class for writing bits (and chars and ints) to an ostream
+ */
+class BitOutputStream {
+
+private:
+  ostream& out;  // the ostream to delegate to
+  char buf;     // the buffer of bits
+  //  bitset<8> buf;     // the buffer of bits
+  int bufi;     // the bit buffer index
+
+public:
+  BitOutputStream(ostream& s) : out(s), buf(0), bufi(0) { }
+  //  BitOutputStream(ostream& s) : out(s), bufi(0) { }
+
+  /** Write the least significant bit of the argument into
+   *  the bit buffer, and increment the bit buffer index.
+   *  Flush to the ostream first if the bit buffer is full.
+   *  This must be consistent with BitInputStream::readBit().
+   */
+  void writeBit(int bit);
+
+  /** Write the least significant byte of the argument to the ostream.
+   *  This function doesn't touch the bit buffer.
+   *  The client has to manage interaction between writing bits
+   *  and writing bytes.
+   */
+  void writeByte(int b);
+
+  /** Write the argument to the ostream.
+   *  This function doesn't touch the bit buffer.
+   *  The client has to manage interaction between writing bits
+   *  and writing ints.
+   */
+  void writeInt(int i);
+
+  /** If the bit buffer contains any bits, flush the bit buffer to the ostream,
+   *  clear the bit buffer, and set the bit buffer index to 0.
+   *  Also flush the ostream itself.
+   */
+  void flush();
+};
+
+#endif // BITOUTPUTSTREAM_HPP
-- 
1.9.1