xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.bin/ftp/pclose.c (revision 533affcbc7fc4d0c8132976ea454aaa715fe2307)
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 #include "ftp_var.h"
41 
42 #ifndef sigmask
43 #define	sigmask(m)	(1 << ((m)-1))
44 #endif
45 
46 #define	set2mask(setp) ((setp)->__sigbits[0])
47 #define	mask2set(mask, setp) \
48 	((mask) == -1 ? sigfillset(setp) : (((setp)->__sigbits[0]) = (mask)))
49 
50 
51 static int
52 sigsetmask(int mask)
53 {
54 	sigset_t oset;
55 	sigset_t nset;
56 
57 	(void) sigprocmask(0, (sigset_t *)0, &nset);
58 	mask2set(mask, &nset);
59 	(void) sigprocmask(SIG_SETMASK, &nset, &oset);
60 	return (set2mask(&oset));
61 }
62 
63 static int
64 sigblock(int mask)
65 {
66 	sigset_t oset;
67 	sigset_t nset;
68 
69 	(void) sigprocmask(0, (sigset_t *)0, &nset);
70 	mask2set(mask, &nset);
71 	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
72 	return (set2mask(&oset));
73 }
74 
75 #define	signal(s, f)	sigset(s, f)
76 
77 #define	tst(a, b)	(*mode == 'r'? (b) : (a))
78 #define	RDR		0
79 #define	WTR		1
80 #define	NOFILES		20	/* just in case */
81 
82 static	pid_t *popen_pid;
83 static	rlim_t nfiles = 0;
84 
85 FILE *
86 mypopen(char *cmd, char *mode)
87 {
88 	int p[2];
89 	pid_t pid;
90 	int myside, remside, i;
91 	struct rlimit rl;
92 
93 	if (nfiles <= 0) {
94 		if (getrlimit(RLIMIT_NOFILE, &rl) == 0)
95 			nfiles = rl.rlim_max;
96 		else
97 			nfiles = NOFILES;
98 	}
99 	if (popen_pid == NULL) {
100 		popen_pid = (pid_t *)malloc((unsigned)nfiles *
101 		    sizeof (*popen_pid));
102 		if (popen_pid == NULL)
103 			return (NULL);
104 		for (i = 0; i < nfiles; i++)
105 			popen_pid[i] = (pid_t)-1;
106 	}
107 	if (pipe(p) < 0)
108 		return (NULL);
109 	myside = tst(p[WTR], p[RDR]);
110 	remside = tst(p[RDR], p[WTR]);
111 	if ((pid = vfork()) == 0) {
112 		/* myside and remside reverse roles in child */
113 		(void) close(myside);
114 		if (remside != tst(0, 1)) {
115 			(void) dup2(remside, tst(0, 1));
116 			(void) close(remside);
117 		}
118 		execl("/bin/sh", "sh", "-c", cmd, (char *)NULL);
119 		_exit(127);
120 	}
121 	if (pid == (pid_t)-1) {
122 		(void) close(myside);
123 		(void) close(remside);
124 		return (NULL);
125 	}
126 	popen_pid[myside] = pid;
127 	(void) close(remside);
128 	return (fdopen(myside, mode));
129 }
130 
131 /*ARGSUSED*/
132 static void
133 pabort(int sig)
134 {
135 	extern int mflag;
136 
137 	mflag = 0;
138 }
139 
140 int
141 mypclose(FILE *ptr)
142 {
143 	pid_t child, pid;
144 	int omask;
145 	void (*istat)();
146 	int status;
147 
148 	child = popen_pid[fileno(ptr)];
149 	popen_pid[fileno(ptr)] = (pid_t)-1;
150 	(void) fclose(ptr);
151 	if (child == (pid_t)-1)
152 		return (-1);
153 	istat = signal(SIGINT, pabort);
154 	omask = sigblock(sigmask(SIGQUIT)|sigmask(SIGHUP));
155 	while ((pid = wait(&status)) != child && pid != (pid_t)-1)
156 		;
157 	(void) sigsetmask(omask);
158 	(void) signal(SIGINT, istat);
159 	return (pid == (pid_t)-1 ? -1 : 0);
160 }
161