Partial frame support.

src/xenia/base/bit_stream.h

@@ -0,0 +1,44 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2015 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_BASE_BIT_STREAM_H_
+#define XENIA_BASE_BIT_STREAM_H_
+
+#include <cstdint>
+
+namespace xe {
+class BitStream {
+ public:
+  BitStream(uint8_t* buffer, size_t size_in_bits);
+  ~BitStream();
+
+  const uint8_t* buffer() const { return buffer_; }
+  uint8_t* buffer() { return buffer_; }
+  size_t offset_bits() const { return offset_bits_; }
+  size_t size_bits() const { return size_bits_; }
+
+  void Advance(size_t num_bits);
+  void SetOffset(size_t offset_bits);
+  size_t BitsRemaining();
+
+  // Note: num_bits MUST be in the range 0-57 (inclusive)
+  uint64_t Peek(size_t num_bits);
+  uint64_t Read(size_t num_bits);
+  bool Write(uint64_t val, size_t num_bits); // TODO: Not tested!
+
+  size_t Copy(uint8_t* dest_buffer, size_t num_bits);
+
+ private:
+  uint8_t* buffer_ = nullptr;
+  size_t offset_bits_ = 0;
+  size_t size_bits_ = 0;
+};
+}  // namespace xe
+
+#endif  // XENIA_BASE_BIT_STREAM_H_