[Spice-devel] [PATCH 08/17] Use C++ style for cursor message initialization instead of C style

[Lukáš Hrázký]

On Fri, 2018-02-16 at 17:15 +0100, Christophe de Dinechin wrote:
> From: Christophe de Dinechin <dinechin at redhat.com>
> 
> Signed-off-by: Christophe de Dinechin <dinechin at redhat.com>
> ---
>  src/spice-streaming-agent.cpp | 47 +++++++++++++++++++++++++------------------
>  1 file changed, 27 insertions(+), 20 deletions(-)
> 
> diff --git a/src/spice-streaming-agent.cpp b/src/spice-streaming-agent.cpp
> index 1e19e43..720173a 100644
> --- a/src/spice-streaming-agent.cpp
> +++ b/src/spice-streaming-agent.cpp
> @@ -285,38 +285,45 @@ static void usage(const char *progname)
>  }
>  
>  static void
> -send_cursor(int streamfd, unsigned width, unsigned height, int hotspot_x, int hotspot_y,
> +send_cursor(int streamfd,
> +            uint16_t width, uint16_t height,
> +            uint16_t hotspot_x, uint16_t hotspot_y,
>              std::function<void(uint32_t *)> fill_cursor)
>  {
>      if (width >= STREAM_MSG_CURSOR_SET_MAX_WIDTH ||
>          height >= STREAM_MSG_CURSOR_SET_MAX_HEIGHT)
>          return;
>  
> -    size_t cursor_size =
> -        sizeof(StreamDevHeader) + sizeof(StreamMsgCursorSet) +
> -        width * height * sizeof(uint32_t);
> -    std::unique_ptr<uint8_t[]> msg(new uint8_t[cursor_size]);
> +    const uint32_t cursor_msgsize =
> +        sizeof(SpiceStreamCursorMessage) + width * height * sizeof(uint32_t);
> +    const uint32_t hdrsize  = sizeof(StreamDevHeader);

Seems like inconsistent naming "cursor_msgsize" vs "hdrsize", two
spaces before =, maybe the sizeof(StreamDevHeader) could be used
directly below.

> -    StreamDevHeader &dev_hdr(*reinterpret_cast<StreamDevHeader*>(msg.get()));
> -    memset(&dev_hdr, 0, sizeof(dev_hdr));
> -    dev_hdr.protocol_version = STREAM_DEVICE_PROTOCOL;
> -    dev_hdr.type = STREAM_TYPE_CURSOR_SET;
> -    dev_hdr.size = cursor_size - sizeof(StreamDevHeader);
> +    std::unique_ptr<uint8_t[]> storage(new uint8_t[cursor_msgsize]);
>  
> -    StreamMsgCursorSet &cursor_msg(*reinterpret_cast<StreamMsgCursorSet *>(msg.get() + sizeof(StreamDevHeader)));
> -    memset(&cursor_msg, 0, sizeof(cursor_msg));
> -
> -    cursor_msg.type = SPICE_CURSOR_TYPE_ALPHA;
> -    cursor_msg.width = width;
> -    cursor_msg.height = height;
> -    cursor_msg.hot_spot_x = hotspot_x;
> -    cursor_msg.hot_spot_y = hotspot_y;
> +    SpiceStreamCursorMessage *cursor_msg =
> +        new(storage.get()) SpiceStreamCursorMessage {
> +        .hdr = {
> +            .protocol_version = STREAM_DEVICE_PROTOCOL,
> +            .padding = 0,       // Workaround GCC internal / not implemented compiler error
> +            .type = STREAM_TYPE_CURSOR_SET,
> +            .size = cursor_msgsize - hdrsize
> +        },
> +        .msg = {
> +            .width = width,
> +            .height = height,
> +            .hot_spot_x = hotspot_x,
> +            .hot_spot_y = hotspot_y,
> +            .type = SPICE_CURSOR_TYPE_ALPHA,
> +            .padding1 = { },
> +            .data = { }
> +        }
> +    };
>  
> -    uint32_t *pixels = reinterpret_cast<uint32_t *>(cursor_msg.data);
> +    uint32_t *pixels = reinterpret_cast<uint32_t *>(cursor_msg->msg.data);
>      fill_cursor(pixels);
>  
>      std::lock_guard<std::mutex> stream_guard(stream_mtx);
> -    write_all(streamfd, msg.get(), cursor_size);
> +    write_all(streamfd, storage.get(), cursor_msgsize);
>  }
>  
>  static void cursor_changes(int streamfd, Display *display, int event_base)