devicesbus read data

src/message_bus/pipeline/PayloadRef.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+
+#include <QMetaType>
+
+#include "core/memory/MemoryPool.h"
+
+namespace softbus::message_bus::pipeline
+{
+
+struct PayloadRef
+{
+    softbus::core::memory::MemoryPool::BlockPtr block;
+    std::size_t offset{0};
+    std::size_t length{0};
+
+    const std::uint8_t* bytes() const
+    {
+        if (!block || !block->data || offset > block->capacity) {
+            return nullptr;
+        }
+        return block->data + offset;
+    }
+
+    bool valid() const
+    {
+        return block && block->data && (offset + length <= block->capacity);
+    }
+};
+
+} // namespace softbus::message_bus::pipeline
+
+Q_DECLARE_METATYPE(softbus::message_bus::pipeline::PayloadRef)