2000-03-05 13:57:01 +00:00
|
|
|
/* sane - Scanner Access Now Easy.
|
2001-08-11 09:46:55 +00:00
|
|
|
Copyright (C) 1998-2001 Yuri Dario
|
2003-10-24 11:23:34 +00:00
|
|
|
Copyright (C) 2002-2003 Henning Meier-Geinitz (documentation)
|
2004-01-13 07:41:06 +00:00
|
|
|
Copyright (C) 2003-2004 Gerhard Jaeger (pthread/process support)
|
2000-03-05 13:57:01 +00:00
|
|
|
This file is part of the SANE package.
|
|
|
|
|
|
|
|
SANE is free software; you can redistribute it and/or modify it under
|
|
|
|
the terms of the GNU General Public License as published by the Free
|
|
|
|
Software Foundation; either version 2 of the License, or (at your
|
|
|
|
option) any later version.
|
|
|
|
|
|
|
|
SANE is distributed in the hope that it will be useful, but WITHOUT
|
|
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
|
|
for more details.
|
|
|
|
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
|
|
along with sane; see the file COPYING. If not, write to the Free
|
|
|
|
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
2003-07-23 14:51:27 +00:00
|
|
|
|
|
|
|
As a special exception, the authors of SANE give permission for
|
|
|
|
additional uses of the libraries contained in this release of SANE.
|
|
|
|
|
|
|
|
The exception is that, if you link a SANE library with other files
|
|
|
|
to produce an executable, this does not by itself cause the
|
|
|
|
resulting executable to be covered by the GNU General Public
|
|
|
|
License. Your use of that executable is in no way restricted on
|
|
|
|
account of linking the SANE library code into it.
|
|
|
|
|
|
|
|
This exception does not, however, invalidate any other reasons why
|
|
|
|
the executable file might be covered by the GNU General Public
|
|
|
|
License.
|
|
|
|
|
|
|
|
If you submit changes to SANE to the maintainers to be included in
|
|
|
|
a subsequent release, you agree by submitting the changes that
|
|
|
|
those changes may be distributed with this exception intact.
|
|
|
|
|
|
|
|
If you write modifications of your own for SANE, it is your choice
|
|
|
|
whether to permit this exception to apply to your modifications.
|
|
|
|
If you do not wish that, delete this exception notice.
|
|
|
|
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
|
|
|
|
|
|
|
/** @file sanei_thread.h
|
2003-10-24 11:23:34 +00:00
|
|
|
* Support for forking processes and threading.
|
|
|
|
*
|
|
|
|
* Backends should not use fork() directly because fork() does not work
|
|
|
|
* correctly on some platforms. Use the functions provided by sanei_thread
|
|
|
|
* instead. The build system decides if fork() or threads are used.
|
|
|
|
*
|
|
|
|
* Please keep in mind that the behaviour of the child process depends
|
|
|
|
* on if it's a process or thread especially concerning variables.
|
|
|
|
*
|
|
|
|
* In this file we use "task" as an umbrella term for process and thread.
|
1994-02-15 21:37:33 +00:00
|
|
|
*
|
|
|
|
* @sa sanei.h sanei_backend.h
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
2000-03-05 13:57:01 +00:00
|
|
|
|
|
|
|
#ifndef sanei_thread_h
|
|
|
|
#define sanei_thread_h
|
2001-08-11 09:46:55 +00:00
|
|
|
#include "../include/sane/config.h"
|
2000-03-05 13:57:01 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Initialize sanei_thread.
|
|
|
|
*
|
|
|
|
* This function must be called before any other sanei_thread function.
|
1994-02-15 21:37:33 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern void sanei_thread_init (void);
|
2003-10-07 07:38:37 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Do we use processes or threads?
|
|
|
|
*
|
|
|
|
* This function can be used to check if processes or threads are used.
|
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - SANE_TRUE - if processes are used (fork)
|
|
|
|
* - SANE_FALSE - i threads are used
|
2003-10-07 07:38:37 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern SANE_Bool sanei_thread_is_forked (void);
|
|
|
|
|
|
|
|
/** Spawn a new task.
|
|
|
|
*
|
|
|
|
* This function should be used to start a new task.
|
|
|
|
*
|
|
|
|
* @param func() function to call as child task
|
|
|
|
* @param args argument of the function (only one!)
|
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - task id
|
|
|
|
* - -1 if creating the new task failed
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
2007-11-16 12:31:59 +00:00
|
|
|
extern int sanei_thread_begin (int (*func) (void *args), void *args);
|
2002-01-19 22:32:05 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Terminate spawned task.
|
|
|
|
*
|
|
|
|
* This function terminates the task that was created with sanei_thread_begin.
|
|
|
|
*
|
|
|
|
* For processes, SIGTERM is sent. If threads are used, pthread_cancel()
|
|
|
|
* terminates the task.
|
|
|
|
*
|
2003-10-08 20:31:15 +00:00
|
|
|
* @param pid - the id of the task
|
2003-10-24 11:23:34 +00:00
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - 0 on success
|
|
|
|
* - any other value if an error occured while terminating the task
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern int sanei_thread_kill (int pid);
|
2002-01-19 22:32:05 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Send a signal to a task.
|
|
|
|
*
|
|
|
|
* This function can be used to send a signal to a task.
|
|
|
|
*
|
|
|
|
* For terminating the task, sanei_thread_kill() should be used.
|
|
|
|
*
|
2003-10-08 20:31:15 +00:00
|
|
|
* @param pid - the id of the task
|
|
|
|
* @param sig - the signal to send
|
2003-10-24 11:23:34 +00:00
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - 0 - on success
|
|
|
|
* - any other value - if an error occured while sending the signal
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern int sanei_thread_sendsig (int pid, int sig);
|
2002-01-19 22:32:05 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Wait for task termination.
|
|
|
|
*
|
|
|
|
* This function waits until a task that has been terminated by
|
|
|
|
* sanei_thread_kill(), sanei_thread_sendsys() or by any other means
|
|
|
|
* is finished.
|
|
|
|
*
|
|
|
|
* @param pid - the id of the task
|
|
|
|
* @param status - status of the task that has just finished
|
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - the pid of the task we have been waiting for
|
2003-10-08 20:31:15 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern int sanei_thread_waitpid (int pid, int *status);
|
2003-10-08 20:31:15 +00:00
|
|
|
|
2003-10-24 11:23:34 +00:00
|
|
|
/** Check the current status of the spawned task
|
|
|
|
*
|
|
|
|
*
|
2003-10-08 20:31:15 +00:00
|
|
|
* @param pid - the id of the task
|
2003-10-24 11:23:34 +00:00
|
|
|
*
|
|
|
|
* @return
|
|
|
|
* - SANE_STATUS_GOOD - if the task finished without errors
|
|
|
|
* - any other value - if the task finished unexpectantly or hasn't finished yet
|
2002-01-19 22:32:05 +00:00
|
|
|
*/
|
2003-10-24 11:23:34 +00:00
|
|
|
extern SANE_Status sanei_thread_get_status (int pid);
|
2000-03-05 13:57:01 +00:00
|
|
|
|
|
|
|
#endif /* sanei_thread_h */
|