github.com/sagernet/gvisor@v0.0.0-20240428053021-e691de28565f/pkg/tcpip/stack/packet_buffer_unsafe.go (about)

     1  // Copyright 2021 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package stack
    16  
    17  import "unsafe"
    18  
    19  // PacketBufferStructSize is the minimal size of the packet buffer overhead.
    20  const PacketBufferStructSize = int(unsafe.Sizeof(PacketBuffer{}))
    21  
    22  // ID returns a unique ID for the underlying storage of the packet.
    23  //
    24  // Two *PacketBuffers have the same IDs if and only if they point to the same
    25  // location in memory.
    26  func (pk *PacketBuffer) ID() uintptr {
    27  	return uintptr(unsafe.Pointer(pk))
    28  }