1 /* $NetBSD: fdopen.c,v 1.6 1997/07/13 20:14:50 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)fdopen.c 8.1 (Berkeley) 6/4/93"; 43 #else 44 __RCSID("$NetBSD: fdopen.c,v 1.6 1997/07/13 20:14:50 christos Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include <sys/types.h> 49 #include <fcntl.h> 50 #include <unistd.h> 51 #include <stdio.h> 52 #include <errno.h> 53 #include "local.h" 54 55 FILE * 56 fdopen(fd, mode) 57 int fd; 58 const char *mode; 59 { 60 register FILE *fp; 61 int flags, oflags, fdflags, tmp; 62 63 if ((flags = __sflags(mode, &oflags)) == 0) 64 return (NULL); 65 66 /* Make sure the mode the user wants is a subset of the actual mode. */ 67 if ((fdflags = fcntl(fd, F_GETFL, 0)) < 0) 68 return (NULL); 69 tmp = fdflags & O_ACCMODE; 70 if (tmp != O_RDWR && (tmp != (oflags & O_ACCMODE))) { 71 errno = EINVAL; 72 return (NULL); 73 } 74 75 if ((fp = __sfp()) == NULL) 76 return (NULL); 77 fp->_flags = flags; 78 /* 79 * If opened for appending, but underlying descriptor does not have 80 * O_APPEND bit set, assert __SAPP so that __swrite() will lseek to 81 * end before each write. 82 */ 83 if ((oflags & O_APPEND) && !(fdflags & O_APPEND)) 84 fp->_flags |= __SAPP; 85 fp->_file = fd; 86 fp->_cookie = fp; 87 fp->_read = __sread; 88 fp->_write = __swrite; 89 fp->_seek = __sseek; 90 fp->_close = __sclose; 91 return (fp); 92 } 93