freebsd-skq/bin/sh/jobs.h
Jilles Tjoelker b823fb59f1 sh: Fix race condition with signals and wait or set -T.
The change in r238888 was incomplete. It was still possible for a trapped
signal to arrive before the shell went to sleep (sigsuspend()) because a
check was missing or because the signal arrived before in_waitcmd was set.

On SMP, this bug sometimes caused the builtins/wait4.0 test to take 1 second
to execute; it then might or might not fail. On UP, the test almost always
failed.
2013-09-02 21:57:46 +00:00

101 lines
3.6 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)jobs.h 8.2 (Berkeley) 5/4/95
* $FreeBSD$
*/
/* Mode argument to forkshell. Don't change FORK_FG or FORK_BG. */
#define FORK_FG 0
#define FORK_BG 1
#define FORK_NOJOB 2
#include <signal.h> /* for sig_atomic_t */
/*
* A job structure contains information about a job. A job is either a
* single process or a set of processes contained in a pipeline. In the
* latter case, pidlist will be non-NULL, and will point to a -1 terminated
* array of pids.
*/
struct procstat {
pid_t pid; /* process id */
int status; /* status flags (defined above) */
char *cmd; /* text of command being run */
};
/* states */
#define JOBSTOPPED 1 /* all procs are stopped */
#define JOBDONE 2 /* all procs are completed */
struct job {
struct procstat ps0; /* status of process */
struct procstat *ps; /* status or processes when more than one */
short nprocs; /* number of processes */
pid_t pgrp; /* process group of this job */
char state; /* true if job is finished */
char used; /* true if this entry is in used */
char changed; /* true if status has changed */
char foreground; /* true if running in the foreground */
char remembered; /* true if $! referenced */
#if JOBS
char jobctl; /* job running under job control */
struct job *next; /* job used after this one */
#endif
};
enum {
SHOWJOBS_DEFAULT, /* job number, status, command */
SHOWJOBS_VERBOSE, /* job number, PID, status, command */
SHOWJOBS_PIDS, /* PID only */
SHOWJOBS_PGIDS /* PID of the group leader only */
};
extern int job_warning; /* user was warned about stopped jobs */
void setjobctl(int);
void showjobs(int, int);
struct job *makejob(union node *, int);
pid_t forkshell(struct job *, union node *, int);
pid_t vforkexecshell(struct job *, char **, char **, const char *, int, int []);
int waitforjob(struct job *, int *);
int stoppedjobs(void);
int backgndpidset(void);
pid_t backgndpidval(void);
char *commandtext(union node *);
#if ! JOBS
#define setjobctl(on) /* do nothing */
#endif