release/src/router/libdaemon/libdaemon/dsignal.h

   1 #ifndef foodaemonsignalhfoo
   2 #define foodaemonsignalhfoo
   3
   4 /***
   5   This file is part of libdaemon.
   6
   7   Copyright 2003-2008 Lennart Poettering
   8
   9   libdaemon is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU Lesser General Public License as
  11   published by the Free Software Foundation, either version 2.1 of the
  12   License, or (at your option) any later version.
  13
  14   libdaemon is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public
  20   License along with libdaemon. If not, see
  21   <http://www.gnu.org/licenses/>.
  22 ***/
  23
  24 #ifdef __cplusplus
  25 extern "C" {
  26 #endif
  27
  28 /** \file
  29  *
  30  * Contains the API for serializing signals to a pipe for
  31  * usage with select() or poll().
  32  *
  33  * You should register all signals you
  34  * wish to handle with select() in your main loop with
  35  * daemon_signal_init() or daemon_signal_install(). After that you
  36  * should sleep on the file descriptor returned by daemon_signal_fd()
  37  * and get the next signal recieved with daemon_signal_next(). You
  38  * should call daemon_signal_done() before exiting.
  39  */
  40
  41 /** Installs signal handlers for the specified signals
  42  * @param s, ... The signals to install handlers for. The list should be terminated by 0
  43  * @return zero on success, nonzero on failure
  44  */
  45 int daemon_signal_init(int s, ...);
  46
  47 /** Install a  signal handler for the specified signal
  48  * @param s The signalto install handler for
  49  * @return zero onsuccess,nonzero on failure
  50  */
  51 int daemon_signal_install(int s);
  52
  53 /** Free resources of signal handling, should be called before daemon exit
  54  */
  55 void daemon_signal_done(void);
  56
  57 /** Return the next signal recieved. This function will not
  58  * block. Instead it returns 0 if no signal is queued.
  59  * @return The next queued signal if one is queued, zero if none is
  60  * queued, negative on failure.
  61  */
  62 int daemon_signal_next(void);
  63
  64 /** Return the file descriptor the daemon should select() on for
  65  * reading. Whenever the descriptor is ready you should call
  66  * daemon_signal_next() to get the next signal queued.
  67  * @return The file descriptor or negative on failure
  68  */
  69 int daemon_signal_fd(void);
  70
  71 #ifdef __cplusplus
  72 }
  73 #endif
  74
  75 #endif