proxy_data.h 文件参考

Zero-copy proxy message envelope carrying raw payload plus routing metadata. 更多...

#include <cstdint>
#include <string_view>
#include "../base/bytes.h"

proxy_data.h 的引用(Include)关系图:

浏览该文件的源代码.

命名空间
namespace	vlink
namespace	vlink::zerocopy

函数
struct	vlink::zerocopy::VLINK_EXPORT_AND_ALIGNED (8) CameraFrame final

详细描述

Zero-copy proxy message envelope carrying raw payload plus routing metadata.

ProxyData is used by the VLink proxy layer to bundle a serialised message with its routing context (URL, serialisation type, source hostname) and control fields (control ID, mode, timestamp, sequence number) into a single flat allocation.

The struct is exactly 80 bytes on 64-bit platforms. Internally a single owned buffer is laid out as:

[ raw data | url string | ser type string | hostname string ]

Position and length of each region are stored as uint32_t fields in the struct itself so that after binary round-trip the sub-buffers can be accessed as std::string_view without additional allocation.

Binary wire format

[ magic_begin (4) | ProxyData struct (80) | variable payload | magic_end (4) ]

Usage

vlink::zerocopy::ProxyData pd;
pd.set_control_id(42);
pd.set_timestamp(get_time_us());
pd.create(raw_bytes, "dds://my/topic", "demo.proto.PointCloud",
          static_cast<uint32_t>(SchemaType::kProtobuf), "host01");
 
vlink::Bytes wire;
pd >> wire;                         // serialise
 
vlink::zerocopy::ProxyData pd2;
pd2 << wire;                        // deserialise (zero-copy, borrows wire)
auto url = pd2.url();               // std::string_view into wire

注解

• 32-bit architectures emit a compile-time warning and are not supported.
• After operator<<, all sub-buffer string_views reference memory inside the source Bytes. The Bytes must outlive the ProxyData.
• is_valid() performs an additional internal consistency check that all position + size values are contiguous and sum correctly.