1 files changed, 89 insertions, 0 deletions
diff --git a/include/libcamera/internal/byte_stream_buffer.h b/include/libcamera/internal/byte_stream_buffer.h
new file mode 100644
index 00000000..b3aaa8b9
--- /dev/null
+++ b/include/libcamera/internal/byte_stream_buffer.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * byte_stream_buffer.h - Byte stream buffer
+ */
+#ifndef __LIBCAMERA_BYTE_STREAM_BUFFER_H__
+#define __LIBCAMERA_BYTE_STREAM_BUFFER_H__
+
+#include <stddef.h>
+#include <stdint.h>
+#include <type_traits>
+
+#include <libcamera/span.h>
+
+namespace libcamera {
+
+class ByteStreamBuffer
+{
+public:
+	ByteStreamBuffer(const uint8_t *base, size_t size);
+	ByteStreamBuffer(uint8_t *base, size_t size);
+	ByteStreamBuffer(ByteStreamBuffer &&other);
+	ByteStreamBuffer &operator=(ByteStreamBuffer &&other);
+
+	const uint8_t *base() const { return base_; }
+	uint32_t offset() const { return (write_ ? write_ : read_) - base_; }
+	size_t size() const { return size_; }
+	bool overflow() const { return overflow_; }
+
+	ByteStreamBuffer carveOut(size_t size);
+	int skip(size_t size);
+
+	template<typename T>
+	int read(T *t)
+	{
+		return read(reinterpret_cast<uint8_t *>(t), sizeof(*t));
+	}
+
+	template<typename T>
+	int read(const Span<T> &data)
+	{
+		return read(reinterpret_cast<uint8_t *>(data.data()),
+			    data.size_bytes());
+	}
+
+	template<typename T>
+	const std::remove_reference_t<T> *read(size_t count = 1)
+	{
+		using return_type = const std::remove_reference_t<T> *;
+		return reinterpret_cast<return_type>(read(sizeof(T), count));
+	}
+
+	template<typename T>
+	int write(const T *t)
+	{
+		return write(reinterpret_cast<const uint8_t *>(t), sizeof(*t));
+	}
+
+	template<typename T>
+	int write(const Span<T> &data)
+	{
+		return write(reinterpret_cast<const uint8_t *>(data.data()),
+			     data.size_bytes());
+	}
+
+private:
+	ByteStreamBuffer(const ByteStreamBuffer &other) = delete;
+	ByteStreamBuffer &operator=(const ByteStreamBuffer &other) = delete;
+
+	void setOverflow();
+
+	int read(uint8_t *data, size_t size);
+	const uint8_t *read(size_t size, size_t count);
+	int write(const uint8_t *data, size_t size);
+
+	ByteStreamBuffer *parent_;
+
+	const uint8_t *base_;
+	size_t size_;
+	bool overflow_;
+
+	const uint8_t *read_;
+	uint8_t *write_;
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_BYTE_STREAM_BUFFER_H__ */