xref: /onnv-gate/usr/src/lib/libbc/libc/stdio/common/fdopen.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 1989 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*      Copyright (c) 1984 AT&T */
28*0Sstevel@tonic-gate /*        All Rights Reserved   */
29*0Sstevel@tonic-gate 
30*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"  /* from S5R2 1.4 */
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate /*LINTLIBRARY*/
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  * Unix routine to do an "fopen" on file descriptor
35*0Sstevel@tonic-gate  * The mode has to be repeated because you can't query its
36*0Sstevel@tonic-gate  * status
37*0Sstevel@tonic-gate  */
38*0Sstevel@tonic-gate 
39*0Sstevel@tonic-gate #include <stdio.h>
40*0Sstevel@tonic-gate #include <sys/errno.h>
41*0Sstevel@tonic-gate 
42*0Sstevel@tonic-gate extern int  errno;
43*0Sstevel@tonic-gate extern long lseek();
44*0Sstevel@tonic-gate extern FILE *_findiop();
45*0Sstevel@tonic-gate 
46*0Sstevel@tonic-gate FILE *
fdopen(fd,mode)47*0Sstevel@tonic-gate fdopen(fd, mode)
48*0Sstevel@tonic-gate int	fd;
49*0Sstevel@tonic-gate register char *mode;
50*0Sstevel@tonic-gate {
51*0Sstevel@tonic-gate 	static int nofile = -1;
52*0Sstevel@tonic-gate 	register FILE *iop;
53*0Sstevel@tonic-gate 
54*0Sstevel@tonic-gate 	if(nofile < 0)
55*0Sstevel@tonic-gate 		nofile = getdtablesize();
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate 	if(fd < 0 || fd >= nofile) {
58*0Sstevel@tonic-gate 		errno = EINVAL;
59*0Sstevel@tonic-gate 		return(NULL);
60*0Sstevel@tonic-gate 	}
61*0Sstevel@tonic-gate 
62*0Sstevel@tonic-gate 	if((iop = _findiop()) == NULL)
63*0Sstevel@tonic-gate 		return(NULL);
64*0Sstevel@tonic-gate 
65*0Sstevel@tonic-gate 	iop->_cnt = 0;
66*0Sstevel@tonic-gate 	iop->_file = fd;
67*0Sstevel@tonic-gate 	iop->_base = iop->_ptr = NULL;
68*0Sstevel@tonic-gate 	iop->_bufsiz = 0;
69*0Sstevel@tonic-gate 	switch(*mode) {
70*0Sstevel@tonic-gate 
71*0Sstevel@tonic-gate 		case 'r':
72*0Sstevel@tonic-gate 			iop->_flag = _IOREAD;
73*0Sstevel@tonic-gate 			break;
74*0Sstevel@tonic-gate 		case 'a':
75*0Sstevel@tonic-gate 			(void) lseek(fd, 0L, 2);
76*0Sstevel@tonic-gate 			/* No break */
77*0Sstevel@tonic-gate 		case 'w':
78*0Sstevel@tonic-gate 			iop->_flag = _IOWRT;
79*0Sstevel@tonic-gate 			break;
80*0Sstevel@tonic-gate 		default:
81*0Sstevel@tonic-gate 			errno = EINVAL;
82*0Sstevel@tonic-gate 			return(NULL);
83*0Sstevel@tonic-gate 	}
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate 	if(mode[1] == '+')
86*0Sstevel@tonic-gate 		iop->_flag = _IORW;
87*0Sstevel@tonic-gate 
88*0Sstevel@tonic-gate 	return(iop);
89*0Sstevel@tonic-gate }
90