Kernel: Implement peek() function for DoubleBuffer

This allows us to "peek" into a DoubleBuffer without incrementing the m_read_buffer_index, which is needed to implement MSG_PEEK.
Author: https://github.com/sw1tchbl4d3r 🔰 Commit: 2d098c88dc Pull-request: https://github.com/SerenityOS/serenity/pull/6715 Reviewed-by: https://github.com/IdanHo Reviewed-by: https://github.com/sin-ack
2025-09-02 15:46:33 +00:00 · 2021-04-28 23:22:21 +02:00 · 2021-04-28 23:22:21 +02:00 · 2d098c88dc · 2024-07-18 18:57:17 +09:00
commit 2d098c88dc
parent 9bcdbe205b
2 changed files with 25 additions and 2 deletions
--- a/Kernel/DoubleBuffer.h
+++ b/Kernel/DoubleBuffer.h
@ -29,6 +29,12 @@ public:
        auto buffer = UserOrKernelBuffer::for_kernel_buffer(data);
        return read(buffer, size);
    }
+    [[nodiscard]] ssize_t peek(UserOrKernelBuffer&, size_t);
+    [[nodiscard]] ssize_t peek(u8* data, size_t size)
+    {
+        auto buffer = UserOrKernelBuffer::for_kernel_buffer(data);
+        return peek(buffer, size);
+    }

    bool is_empty() const { return m_empty; }