yew011 / haskell_unix_domain_socket_client

Unix domain socket communication client written in Haskell.

Unix Domain Socket Client in Haskell

Example program which can connect to a unix domain socket, read a uint32_t intger and echo it back.

This is an experiment toy for testing my memory sharing change to the stenographer project.

How to Parse PacketV3 Block

Format

POSIX Memory Sharing
====================

Between stenographer and this client.

+-----------+-----------+-----------+-----------+
| 1MB Block | 1MB Block | ... ...   | 1MB Block |
+-----------+-----------+-----------+-----------+

1MB Block									Memory Address
=========									==============
											     ||
+--------------------------------+			     ||
|                                |			     ||
|   struct tpacket_block_desc    |			     ||
|                                |			     ||
|--------------------------------|			     ||
|                                |			     ||
|   struct tpacket3_hdr          |			     ||
|                                |			     ||
|--------------------------------|			     ||
|                                |			     ||
|   packet                       |			     ||
|                                |			     ||
|--------------------------------|			     \/
|                                |
|   ...                          |
|                                |
|--------------------------------|
|                                |
|   struct tpacket3_hdr          |
|                                |
|--------------------------------|
|                                |
|   packet                       |
|                                |
+--------------------------------+

Useful Fields

• The "tpacket_block_desc->hdr->num_pkts" records the number of packet in the block.
• The "tpacket3_hdr->tp_next_offset" provides the offset from the starting address of the "struct tpacket3_hrd" to the next one.
• The "tpacket3_hdr->tp_nsec" provides the timestamp in nanoseconds (I think).

Kernel Header File

if_packet.h