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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* cscope - interactive C symbol cross-reference
*
* process execution functions
*/
#include "global.h"
#include <sys/types.h>
#include <sys/wait.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <libgen.h>
#define getdtablesize() _NFILE
#define MAXARGS 100 /* maximum number of arguments to executed command */
pid_t childpid; /* child's process ID */
static SIGTYPE (*oldsigquit)(); /* old value of quit signal */
static SIGTYPE (*oldsigtstp)(); /* old value of terminal stop signal */
static pid_t myfork(void);
static int join(pid_t p);
/*
* execute forks and executes a program or shell script, waits for it to
* finish, and returns its exit code.
*/
/*VARARGS0*/
int
execute(char *path, ...)
{
va_list ap;
char *args[MAXARGS + 1];
int exitcode;
int i;
char msg[MSGLEN + 1];
pid_t p;
/* fork and exec the program or shell script */
exitcurses();
if ((p = myfork()) == 0) {
/* close all files except stdin, stdout, and stderr */
for (i = 3; i < getdtablesize() && close(i) == 0; ++i) {
;
}
/* execute the program or shell script */
va_start(ap, path);
for (i = 0; i < MAXARGS &&
(args[i] = va_arg(ap, char *)) != NULL; ++i) {
}
va_end(ap);
args[i] = NULL; /* in case MAXARGS reached */
args[0] = basename(args[0]);
(void) execvp(path, args); /* returns only on failure */
(void) sprintf(msg, "\ncscope: cannot execute %s", path);
(void) perror(msg); /* display the reason */
askforreturn(); /* wait until the user sees the message */
exit(1); /* exit the child */
} else {
exitcode = join(p); /* parent */
}
if (noacttimeout) {
(void) fprintf(stderr,
"cscope: no activity time out--exiting\n");
myexit(SIGALRM);
}
entercurses();
return (exitcode);
}
/* myfork acts like fork but also handles signals */
static pid_t
myfork(void)
{
pid_t p; /* process number */
oldsigtstp = signal(SIGTSTP, SIG_DFL);
/* the parent ignores the interrupt and quit signals */
if ((p = fork()) > 0) {
childpid = p;
oldsigquit = signal(SIGQUIT, SIG_IGN);
}
/* so they can be used to stop the child */
else if (p == 0) {
(void) signal(SIGINT, SIG_DFL);
(void) signal(SIGQUIT, SIG_DFL);
(void) signal(SIGHUP, SIG_DFL); /* restore hangup default */
}
/* check for fork failure */
if (p == -1) {
myperror("Cannot fork");
}
return (p);
}
/* join is the compliment of fork */
static int
join(pid_t p)
{
int status;
pid_t w;
/* wait for the correct child to exit */
do {
w = wait(&status);
} while (p != -1 && w != p);
childpid = 0;
/* restore signal handling */
(void) signal(SIGQUIT, oldsigquit);
(void) signal(SIGTSTP, oldsigtstp);
/* return the child's exit code */
return (status >> 8);
}
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