xref: /illumos-gate/usr/src/cmd/ypcmd/ypupdated/openchild.c (revision 2aeafac3612e19716bf8164f89c3c9196342979c)
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 /*
36  * openchild.c
37  *
38  * Open two pipes to a child process, one for reading, one for writing.
39  * The pipes are accessed by FILE pointers. This is NOT a public
40  * interface, but for internal use only!
41  */
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <strings.h>
45 
46 static char *basename(char *);
47 static char SHELL[] = "/bin/sh";
48 
49 /*
50  * returns pid, or -1 for failure
51  */
52 int
53 _openchild(char *command, FILE **fto, FILE **ffrom)
54 {
55 	int i;
56 	int pid;
57 	int pdto[2];
58 	int pdfrom[2];
59 	char *com;
60 
61 
62 	if (pipe(pdto) < 0) {
63 		goto error1;
64 	}
65 	if (pipe(pdfrom) < 0) {
66 		goto error2;
67 	}
68 	switch (pid = fork()) {
69 	case -1:
70 		goto error3;
71 
72 	case 0:
73 		/*
74 		 * child: read from pdto[0], write into pdfrom[1]
75 		 */
76 		(void) close(0);
77 		(void) dup(pdto[0]);
78 		(void) close(1);
79 		(void) dup(pdfrom[1]);
80 
81 		/*
82 		 * adding this closelog for bug id 1238429
83 		 */
84 		closelog();
85 		closefrom(3);
86 
87 		com = malloc((unsigned)strlen(command) + 6);
88 		if (com == NULL) {
89 			exit(1);
90 		}
91 		(void) sprintf(com, "exec %s", command);
92 		execl(SHELL, basename(SHELL), "-c", com, NULL);
93 		exit(1);
94 
95 	default:
96 		/*
97 		 * parent: write into pdto[1], read from pdfrom[0]
98 		 */
99 		*fto = fdopen(pdto[1], "w");
100 		(void) close(pdto[0]);
101 		*ffrom = fdopen(pdfrom[0], "r");
102 		(void) close(pdfrom[1]);
103 		break;
104 	}
105 	return (pid);
106 
107 	/*
108 	 * error cleanup and return
109 	 */
110 error3:
111 printf("openchild: error3");
112 	(void) close(pdfrom[0]);
113 	(void) close(pdfrom[1]);
114 error2:
115 printf("openchild: error2");
116 	(void) close(pdto[0]);
117 	(void) close(pdto[1]);
118 error1:
119 printf("openchild: error1");
120 	return (-1);
121 }
122 
123 static char *
124 basename(char *path)
125 {
126 	char *p;
127 
128 	p = strrchr(path, '/');
129 	if (p == NULL) {
130 		return (path);
131 	} else {
132 		return (p + 1);
133 	}
134 }
135