usr/src/cmd/ypcmd/ypupdated/openchild.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  *      Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  *      Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * Portions of this source code were derived from Berkeley 4.3 BSD
  32  * under license from the Regents of the University of California.
  33  */
  34
  35 #pragma ident   "%Z%%M% %I%     %E% SMI"
  36
  37 #if !defined(lint) && defined(SCCSIDS)
  38 static char sccsid[] = "%Z%%M%  %I%     %E% SMI";
  39 #endif
  40
  41 /*
  42  * openchild.c
  43  *
  44  * Open two pipes to a child process, one for reading, one for writing.
  45  * The pipes are accessed by FILE pointers. This is NOT a public
  46  * interface, but for internal use only!
  47  */
  48 #include <stdio.h>
  49
  50 extern void *malloc();
  51 extern char *strrchr();
  52
  53 static char *basename();
  54 static char SHELL[] = "/bin/sh";
  55
  56 extern int close();
  57 extern int dup();
  58 extern int execl();
  59 extern void exit();
  60 extern long fork();
  61 extern int pipe();
  62 extern unsigned int strlen();
  63
  64 /*
  65  * returns pid, or -1 for failure
  66  */
  67 int
  68 _openchild(command, fto, ffrom)
  69         char *command;
  70         FILE **fto;
  71         FILE **ffrom;
  72 {
  73         int i;
  74         int pid;
  75         int pdto[2];
  76         int pdfrom[2];
  77         char *com;
  78
  79
  80         if (pipe(pdto) < 0) {
  81                 goto error1;
  82         }
  83         if (pipe(pdfrom) < 0) {
  84                 goto error2;
  85         }
  86         switch (pid = fork()) {
  87         case -1:
  88                 goto error3;
  89
  90         case 0:
  91                 /*
  92                  * child: read from pdto[0], write into pdfrom[1]
  93                  */
  94                 (void) close(0);
  95                 (void) dup(pdto[0]);
  96                 (void) close(1);
  97                 (void) dup(pdfrom[1]);
  98
  99                 /*
 100                  * adding this closelog for bug id 1238429
 101                  */
 102                 closelog();
 103                 closefrom(3);
 104
 105                 com = malloc((unsigned)strlen(command) + 6);
 106                 if (com == NULL) {
 107                         exit(1);
 108                 }
 109                 (void) sprintf(com, "exec %s", command);
 110                 execl(SHELL, basename(SHELL), "-c", com, NULL);
 111                 exit(1);
 112
 113         default:
 114                 /*
 115                  * parent: write into pdto[1], read from pdfrom[0]
 116                  */
 117                 *fto = fdopen(pdto[1], "w");
 118                 (void) close(pdto[0]);
 119                 *ffrom = fdopen(pdfrom[0], "r");
 120                 (void) close(pdfrom[1]);
 121                 break;
 122         }
 123         return (pid);
 124
 125         /*
 126          * error cleanup and return
 127          */
 128 error3:
 129 printf("openchild: error3");
 130         (void) close(pdfrom[0]);
 131         (void) close(pdfrom[1]);
 132 error2:
 133 printf("openchild: error2");
 134         (void) close(pdto[0]);
 135         (void) close(pdto[1]);
 136 error1:
 137 printf("openchild: error1");
 138         return (-1);
 139 }
 140
 141 static char *
 142 basename(path)
 143         char *path;
 144 {
 145         char *p;
 146
 147         p = strrchr(path, '/');
 148         if (p == NULL) {
 149                 return (path);
 150         } else {
 151                 return (p + 1);
 152         }
 153 }