bgpd/bgp_io.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* BGP I/O.
   3  * Implements packet I/O in a pthread.
   4  * Copyright (C) 2017  Cumulus Networks
   5  * Quentin Young
   6  */
   7
   8 #ifndef _FRR_BGP_IO_H
   9 #define _FRR_BGP_IO_H
  10
  11 #define BGP_WRITE_PACKET_MAX 64U
  12 #define BGP_READ_PACKET_MAX  10U
  13
  14 #include "bgpd/bgpd.h"
  15 #include "frr_pthread.h"
  16
  17 /**
  18  * Start function for write thread.
  19  *
  20  * @param arg - unused
  21  */
  22 extern void *bgp_io_start(void *arg);
  23
  24 /**
  25  * Start function for write thread.
  26  *
  27  * Uninitializes all resources and stops the thread.
  28  *
  29  * @param result - where to store data result, unused
  30  */
  31 extern int bgp_io_stop(void **result, struct frr_pthread *fpt);
  32
  33 /**
  34  * Turns on packet writing for a peer.
  35  *
  36  * After this function is called, any packets placed on peer->obuf will be
  37  * written to peer->fd until no more packets remain.
  38  *
  39  * Additionally, it becomes unsafe to perform socket actions on peer->fd.
  40  *
  41  * @param peer - peer to register
  42  */
  43 extern void bgp_writes_on(struct peer *peer);
  44
  45 /**
  46  * Turns off packet writing for a peer.
  47  *
  48  * After this function returns, packets placed on peer->obuf will not be
  49  * written to peer->fd by the I/O thread.
  50  *
  51  * After this function returns it becomes safe to perform socket actions on
  52  * peer->fd.
  53  *
  54  * @param peer - peer to deregister
  55  * @param flush - as described
  56  */
  57 extern void bgp_writes_off(struct peer *peer);
  58
  59 /**
  60  * Turns on packet reading for a peer.
  61  *
  62  * After this function is called, any packets received on peer->fd will be read
  63  * and copied into the FIFO queue peer->ibuf.
  64  *
  65  * Additionally, it becomes unsafe to perform socket actions on peer->fd.
  66  *
  67  * Whenever one or more packets are placed onto peer->ibuf, a task of type
  68  * THREAD_EVENT will be placed on the main thread whose handler is
  69  *
  70  *   bgp_packet.c:bgp_process_packet()
  71  *
  72  * @param peer - peer to register
  73  */
  74 extern void bgp_reads_on(struct peer *peer);
  75
  76 /**
  77  * Turns off packet reading for a peer.
  78  *
  79  * After this function is called, any packets received on peer->fd will not be
  80  * read by the I/O thread.
  81  *
  82  * After this function returns it becomes safe to perform socket actions on
  83  * peer->fd.
  84  *
  85  * @param peer - peer to deregister
  86  */
  87 extern void bgp_reads_off(struct peer *peer);
  88
  89 #endif /* _FRR_BGP_IO_H */