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 1996 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  *	University Copyright- Copyright (c) 1982, 1986, 1988
32  *	The Regents of the University of California
33  *	All Rights Reserved
34  *
35  *	University Acknowledgment- Portions of this document are derived from
36  *	software developed by the University of California, Berkeley, and its
37  *	contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 #include "ftp_var.h"
43 
44 #ifndef sigmask
45 #define	sigmask(m)	(1 << ((m)-1))
46 #endif
47 
48 #define	set2mask(setp) ((setp)->__sigbits[0])
49 #define	mask2set(mask, setp) \
50 	((mask) == -1 ? sigfillset(setp) : (((setp)->__sigbits[0]) = (mask)))
51 
52 
53 static int
sigsetmask(int mask)54 sigsetmask(int mask)
55 {
56 	sigset_t oset;
57 	sigset_t nset;
58 
59 	(void) sigprocmask(0, (sigset_t *)0, &nset);
60 	mask2set(mask, &nset);
61 	(void) sigprocmask(SIG_SETMASK, &nset, &oset);
62 	return (set2mask(&oset));
63 }
64 
65 static int
sigblock(int mask)66 sigblock(int mask)
67 {
68 	sigset_t oset;
69 	sigset_t nset;
70 
71 	(void) sigprocmask(0, (sigset_t *)0, &nset);
72 	mask2set(mask, &nset);
73 	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
74 	return (set2mask(&oset));
75 }
76 
77 #define	signal(s, f)	sigset(s, f)
78 
79 #define	tst(a, b)	(*mode == 'r'? (b) : (a))
80 #define	RDR		0
81 #define	WTR		1
82 #define	NOFILES		20	/* just in case */
83 
84 static	pid_t *popen_pid;
85 static	rlim_t nfiles = 0;
86 
87 FILE *
mypopen(char * cmd,char * mode)88 mypopen(char *cmd, char *mode)
89 {
90 	int p[2];
91 	pid_t pid;
92 	int myside, remside, i;
93 	struct rlimit rl;
94 
95 	if (nfiles <= 0) {
96 		if (getrlimit(RLIMIT_NOFILE, &rl) == 0)
97 			nfiles = rl.rlim_max;
98 		else
99 			nfiles = NOFILES;
100 	}
101 	if (popen_pid == NULL) {
102 		popen_pid = (pid_t *)malloc((unsigned)nfiles *
103 		    sizeof (*popen_pid));
104 		if (popen_pid == NULL)
105 			return (NULL);
106 		for (i = 0; i < nfiles; i++)
107 			popen_pid[i] = (pid_t)-1;
108 	}
109 	if (pipe(p) < 0)
110 		return (NULL);
111 	myside = tst(p[WTR], p[RDR]);
112 	remside = tst(p[RDR], p[WTR]);
113 	if ((pid = vfork()) == 0) {
114 		/* myside and remside reverse roles in child */
115 		(void) close(myside);
116 		if (remside != tst(0, 1)) {
117 			(void) dup2(remside, tst(0, 1));
118 			(void) close(remside);
119 		}
120 		execl("/bin/sh", "sh", "-c", cmd, (char *)NULL);
121 		_exit(127);
122 	}
123 	if (pid == (pid_t)-1) {
124 		(void) close(myside);
125 		(void) close(remside);
126 		return (NULL);
127 	}
128 	popen_pid[myside] = pid;
129 	(void) close(remside);
130 	return (fdopen(myside, mode));
131 }
132 
133 /*ARGSUSED*/
134 static void
pabort(int sig)135 pabort(int sig)
136 {
137 	extern int mflag;
138 
139 	mflag = 0;
140 }
141 
142 int
mypclose(FILE * ptr)143 mypclose(FILE *ptr)
144 {
145 	pid_t child, pid;
146 	int omask;
147 	void (*istat)();
148 	int status;
149 
150 	child = popen_pid[fileno(ptr)];
151 	popen_pid[fileno(ptr)] = (pid_t)-1;
152 	(void) fclose(ptr);
153 	if (child == (pid_t)-1)
154 		return (-1);
155 	istat = signal(SIGINT, pabort);
156 	omask = sigblock(sigmask(SIGQUIT)|sigmask(SIGHUP));
157 	while ((pid = wait(&status)) != child && pid != (pid_t)-1)
158 		;
159 	(void) sigsetmask(omask);
160 	(void) signal(SIGINT, istat);
161 	return (pid == (pid_t)-1 ? -1 : 0);
162 }
163