ypcmd/ypupdated/openchild.c

/*
 * 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 2005 Sun Microsystems, Inc.  All rights reserved.
 *  Use is subject to license terms.
 */

/*  Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * Portions of this source code were derived from Berkeley 4.3 BSD
 * under license from the Regents of the University of California.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "%Z%%M%  %I% %E% SMI";
#endif

/*
 * openchild.c
 *
 * Open two pipes to a child process, one for reading, one for writing.
 * The pipes are accessed by FILE pointers. This is NOT a public
 * interface, but for internal use only!
 */
#include <stdio.h>

extern void *malloc();
extern char *strrchr();

static char *basename();
static char SHELL[] = "/bin/sh";

extern int close();
extern int dup();
extern int execl();
extern void exit();
extern long fork();
extern int pipe();
extern unsigned int strlen();

/*
 * returns pid, or -1 for failure
 */
int
_openchild(command, fto, ffrom)
    char *command;
    FILE **fto;
    FILE **ffrom;
{
    int i;
    int pid;
    int pdto[2];
    int pdfrom[2];
    char *com;


    if (pipe(pdto) < 0) {
        goto error1;
    }
    if (pipe(pdfrom) < 0) {
        goto error2;
    }
    switch (pid = fork()) {
    case -1:
        goto error3;

    case 0:
        /*
         * child: read from pdto[0], write into pdfrom[1]
         */
        (void) close(0);
        (void) dup(pdto[0]);
        (void) close(1);
        (void) dup(pdfrom[1]);

        /*
         * adding this closelog for bug id 1238429
         */
        closelog();
        closefrom(3);

        com = malloc((unsigned)strlen(command) + 6);
        if (com == NULL) {
            exit(1);
        }
        (void) sprintf(com, "exec %s", command);
        execl(SHELL, basename(SHELL), "-c", com, NULL);
        exit(1);

    default:
        /*
         * parent: write into pdto[1], read from pdfrom[0]
         */
        *fto = fdopen(pdto[1], "w");
        (void) close(pdto[0]);
        *ffrom = fdopen(pdfrom[0], "r");
        (void) close(pdfrom[1]);
        break;
    }
    return (pid);

    /*
     * error cleanup and return
     */
error3:
printf("openchild: error3");
    (void) close(pdfrom[0]);
    (void) close(pdfrom[1]);
error2:
printf("openchild: error2");
    (void) close(pdto[0]);
    (void) close(pdto[1]);
error1:
printf("openchild: error1");
    return (-1);
}

static char *
basename(path)
    char *path;
{
    char *p;

    p = strrchr(path, '/');
    if (p == NULL) {
        return (path);
    } else {
        return (p + 1);
    }
}