libcamera: byte_stream_buffer: Add Span<> support

Add support to write and read a Span<> to and from the ByteStreamBuffer
class.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

2 files changed, 35 insertions, 0 deletions

diff --git a/src/libcamera/byte_stream_buffer.cpp b/src/libcamera/byte_stream_buffer.cpp
index cd1d8a36..17e710c4 100644
--- a/src/libcamera/byte_stream_buffer.cpp
+++ b/src/libcamera/byte_stream_buffer.cpp
@@ -233,6 +233,15 @@ int ByteStreamBuffer::skip(size_t size)
  */
 
 /**
+ * \fn template<typename T> int ByteStreamBuffer::read(const Span<T> &data)
+ * \brief Read data from the managed memory buffer into Span \a data
+ * \param[out] data Span representing the destination memory
+ * \return 0 on success, a negative error code otherwise
+ * \retval -EACCES attempting to read from a write buffer
+ * \retval -ENOSPC no more space is available in the managed memory buffer
+ */
+
+/**
  * \fn template<typename T> int ByteStreamBuffer::write(const T *t)
  * \brief Write \a t to the managed memory buffer
  * \param[in] t The data to write to memory
@@ -241,6 +250,15 @@ int ByteStreamBuffer::skip(size_t size)
  * \retval -ENOSPC no more space is available in the managed memory buffer
  */
 
+/**
+ * \fn template<typename T> int ByteStreamBuffer::write(const Span<T> &data)
+ * \brief Write \a data to the managed memory buffer
+ * \param[in] data The data to write to memory
+ * \return 0 on success, a negative error code otherwise
+ * \retval -EACCES attempting to write to a read buffer
+ * \retval -ENOSPC no more space is available in the managed memory buffer
+ */
+
 int ByteStreamBuffer::read(uint8_t *data, size_t size)
 {
 	if (!read_)
diff --git a/src/libcamera/include/byte_stream_buffer.h b/src/libcamera/include/byte_stream_buffer.h
index b5274c62..17cb0146 100644
--- a/src/libcamera/include/byte_stream_buffer.h
+++ b/src/libcamera/include/byte_stream_buffer.h
@@ -10,6 +10,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include <libcamera/span.h>
+
 namespace libcamera {
 
 class ByteStreamBuffer
@@ -33,12 +35,27 @@ public:
 	{
 		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>
 	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;