xref: /titanic_50/usr/src/ucblib/libucb/port/stdio/fopen.c (revision 0b5ce10aee80822ecc7df77df92a5e24078ba196)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 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 /*LINTLIBRARY*/
41 
42 #include <sys/types.h>
43 #include "file64.h"
44 #include <stdio.h>
45 #include <sys/fcntl.h>
46 #include <unistd.h>
47 #include <sys/file.h>
48 #include "stdiom.h"
49 
50 /* Final argument to _endopen depends on build environment */
51 #define	ALWAYS_LARGE_OPEN	1
52 #define	LARGE_OPEN	(_FILE_OFFSET_BITS == 64)
53 
54 static FILE *
55 _endopen(const char *file, const char *mode, FILE *iop, int largefile)
56 {
57 	int	plus, oflag, fd;
58 
59 	if (iop == NULL || file == NULL || file[0] == '\0')
60 		return (NULL);
61 	plus = (mode[1] == '+');
62 	switch (mode[0]) {
63 	case 'w':
64 		oflag = (plus ? O_RDWR : O_WRONLY) | O_TRUNC | O_CREAT;
65 		break;
66 	case 'a':
67 		oflag = (plus ? O_RDWR : O_WRONLY) | O_CREAT;
68 		break;
69 	case 'r':
70 		oflag = plus ? O_RDWR : O_RDONLY;
71 		break;
72 	default:
73 		return (NULL);
74 	}
75 
76 	if (largefile) {
77 		fd = open64(file, oflag, 0666);	/* mapped to open() for V9 */
78 	} else {
79 		fd = open(file, oflag, 0666);
80 	}
81 	if (fd < 0)
82 		return (NULL);
83 	iop->_cnt = 0;
84 #ifdef _LP64
85 	iop->_file = fd;
86 #else
87 	if (fd <= _FILE_FD_MAX) {
88 		SET_FILE(iop, fd);
89 	} else if (_file_set(iop, fd, mode) != 0) {
90 		/* errno set in _file_set() */
91 		(void) close(fd);
92 		return (NULL);
93 	}
94 #endif
95 	iop->_flag = plus ? _IORW : (mode[0] == 'r') ? _IOREAD : _IOWRT;
96 	if (mode[0] == 'a')   {
97 		if ((lseek64(fd, 0L, SEEK_END)) < 0)  {
98 			(void) close(fd);
99 			return (NULL);
100 		}
101 	}
102 	iop->_base = iop->_ptr = NULL;
103 	/*
104 	 * Sys5 does not support _bufsiz
105 	 *
106 	 * iop->_bufsiz = 0;
107 	 */
108 	return (iop);
109 }
110 
111 FILE *
112 fopen(const char *file, const char *mode)
113 {
114 	FILE	*iop;
115 	FILE	*rc;
116 
117 	iop = _findiop();
118 	rc = _endopen(file, mode, iop, LARGE_OPEN);
119 	if (rc == NULL && iop != NULL)
120 		iop->_flag = 0;	/* release iop */
121 	return (rc);
122 }
123 
124 /*
125  * For _LP64, all fopen() calls are 64-bit calls, i.e., open64() system call.
126  * There should not be fopen64() calls.
127  * Similar for freopen64().
128  */
129 #if !defined(_LP64)
130 FILE *
131 fopen64(const char *file, const char *mode)
132 {
133 	FILE	*iop;
134 	FILE	*rc;
135 
136 	iop = _findiop();
137 	rc = _endopen(file, mode, iop, ALWAYS_LARGE_OPEN);
138 	if (rc == NULL && iop != NULL)
139 		iop->_flag = 0;	/* release iop */
140 	return (rc);
141 }
142 #endif
143 
144 FILE *
145 freopen(const char *file, const char *mode, FILE *iop)
146 {
147 	(void) fclose(iop); /* doesn't matter if this fails */
148 	return (_endopen(file, mode, iop, LARGE_OPEN));
149 }
150 
151 #if !defined(_LP64)
152 FILE *
153 freopen64(const char *file, const char *mode, FILE *iop)
154 {
155 	(void) fclose(iop); /* doesn't matter if this fails */
156 	return (_endopen(file, mode, iop, ALWAYS_LARGE_OPEN));
157 }
158 #endif
159