src/sys/loop.h

   1 /** @file loop.h
   2  *  Declarations for program main loop
   3 */
   4 /*  2ooM: The Master of Orion II Reverse Engineering Project
   5  *  Copyright (C) 2006 Nick Bowler
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  */
  21
  22 #ifndef LOOP_H_
  23 #define LOOP_H_
  24
  25 /** Adds a procedure to the main loop.
  26  * The procedure is added to an internal list and is then called as part of the
  27  * program main loop.  If the callback procedure returns a non-zero value, the
  28  * main loop will end.
  29  *
  30  * @see loop_delfunc
  31  * @param callback Procedure to add to main loop.
  32  * @return An identifier for the added procedure, or -1 on failure.
  33  */
  34 int loop_addfunc(int (*callback)(void));
  35
  36 /** Removes a procedure from the main loop.
  37  * The specified procedure which was previously added to the main loop is
  38  * removed from the internal list.  It will no longer be called as part of the
  39  * program main loop.
  40  *
  41  * @see loop_addfunc
  42  * @param entry Identifier for the procedure, as returned by loop_addfunc().
  43  * @return 0 if successful, otherwise -1.
  44  */
  45 int loop_delfunc(int entry);
  46
  47 /** Starts the program main loop.
  48  * Begins executing procedures added to the internal list.  At least one
  49  * procedure must be added prior to calling this routine.  The loop ends when
  50  * one of the procedures returns a nonzero value.  Note that if no procedure
  51  * in the list blocks, this loop will not be friendly towards the scheduler...
  52  *
  53  * @see loop_addfunc
  54  * @see loop_delfunc
  55  * @return 0 on normal loop exit, -1 if the procedure list was empty.
  56  */
  57 int loop_run(void);
  58
  59 #endif