1 files changed, 60 insertions, 0 deletions
diff --git a/xfa/src/fxbarcode/src/BC_CommonBitSource.cpp b/xfa/src/fxbarcode/src/BC_CommonBitSource.cpp
new file mode 100644
index 0000000000..de29002753
--- /dev/null
+++ b/xfa/src/fxbarcode/src/BC_CommonBitSource.cpp
@@ -0,0 +1,60 @@
+// Copyright 2014 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "barcode.h"
+#include "include/BC_CommonBitSource.h"
+CBC_CommonBitSource::CBC_CommonBitSource(CFX_ByteArray* bytes)
+{
+    m_bytes.Copy((*bytes));
+    m_bitOffset = 0;
+    m_byteOffset = 0;
+}
+CBC_CommonBitSource::~CBC_CommonBitSource()
+{
+}
+FX_INT32 CBC_CommonBitSource::ReadBits(FX_INT32 numBits, FX_INT32 &e)
+{
+    if (numBits < 1 || numBits > 32) {
+        e = BCExceptionIllegalArgument;
+        return 0;
+    }
+    FX_INT32 result = 0;
+    if (m_bitOffset > 0) {
+        FX_INT32 bitsLeft = 8 - m_bitOffset;
+        FX_INT32 toRead = numBits < bitsLeft ? numBits : bitsLeft;
+        FX_INT32 bitsToNotRead = bitsLeft - toRead;
+        FX_INT32 mask = (0xff >> (8 - toRead)) << bitsToNotRead;
+        result = (m_bytes[m_byteOffset] & mask) >> bitsToNotRead;
+        numBits -= toRead;
+        m_bitOffset += toRead;
+        if (m_bitOffset == 8) {
+            m_bitOffset = 0;
+            m_byteOffset++;
+        }
+    }
+    if (numBits > 0) {
+        while(numBits >= 8) {
+            result = (result << 8) | (m_bytes[m_byteOffset] & 0xff);
+            m_byteOffset++;
+            numBits -= 8;
+        }
+        if (numBits > 0) {
+            FX_INT32 bitsToNotRead = 8 - numBits;
+            FX_INT32 mask = (0xff >> bitsToNotRead) << bitsToNotRead;
+            result = (result << numBits) | ((m_bytes[m_byteOffset] & mask) >> bitsToNotRead);
+            m_bitOffset += numBits;
+        }
+    }
+    return result;
+}
+FX_INT32 CBC_CommonBitSource::Available()
+{
+    return 8 * (m_bytes.GetSize() - m_byteOffset) - m_bitOffset;
+}
+FX_INT32 CBC_CommonBitSource::getByteOffset()
+{
+    return m_byteOffset;
+}