src/lib/net/alertsock.h

   1 /* Copyright (c) 2003-2004, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file alertsock.h
   8  *
   9  * \brief Header for alertsock.c
  10  **/
  11
  12 #ifndef TOR_ALERTSOCK_H
  13 #define TOR_ALERTSOCK_H
  14
  15 #include "orconfig.h"
  16 #include "lib/net/nettypes.h"
  17 #include "lib/cc/torint.h"
  18
  19 /** Helper type used to manage waking up the main thread while it's in
  20  * the libevent main loop.  Used by the work queue code. */
  21 typedef struct alert_sockets_t {
  22   /* XXXX This structure needs a better name. */
  23   /** Socket that the main thread should listen for EV_READ events on.
  24    * Note that this socket may be a regular fd on a non-Windows platform.
  25    */
  26   tor_socket_t read_fd;
  27   /** Socket to use when alerting the main thread. */
  28   tor_socket_t write_fd;
  29   /** Function to alert the main thread */
  30   int (*alert_fn)(tor_socket_t write_fd);
  31   /** Function to make the main thread no longer alerted. */
  32   int (*drain_fn)(tor_socket_t read_fd);
  33 } alert_sockets_t;
  34
  35 /* Flags to disable one or more alert_sockets backends. */
  36 #define ASOCKS_NOEVENTFD2   (1u<<0)
  37 #define ASOCKS_NOEVENTFD    (1u<<1)
  38 #define ASOCKS_NOPIPE2      (1u<<2)
  39 #define ASOCKS_NOPIPE       (1u<<3)
  40 #define ASOCKS_NOSOCKETPAIR (1u<<4)
  41
  42 int alert_sockets_create(alert_sockets_t *socks_out, uint32_t flags);
  43 void alert_sockets_close(alert_sockets_t *socks);
  44
  45 #endif /* !defined(TOR_ALERTSOCK_H) */