fdopen.c revision 56698
11573Srgrimes/*- 21573Srgrimes * Copyright (c) 1990, 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * This code is derived from software contributed to Berkeley by 61573Srgrimes * Chris Torek. 71573Srgrimes * 81573Srgrimes * Redistribution and use in source and binary forms, with or without 91573Srgrimes * modification, are permitted provided that the following conditions 101573Srgrimes * are met: 111573Srgrimes * 1. Redistributions of source code must retain the above copyright 121573Srgrimes * notice, this list of conditions and the following disclaimer. 131573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141573Srgrimes * notice, this list of conditions and the following disclaimer in the 151573Srgrimes * documentation and/or other materials provided with the distribution. 161573Srgrimes * 3. All advertising materials mentioning features or use of this software 171573Srgrimes * must display the following acknowledgement: 181573Srgrimes * This product includes software developed by the University of 191573Srgrimes * California, Berkeley and its contributors. 201573Srgrimes * 4. Neither the name of the University nor the names of its contributors 211573Srgrimes * may be used to endorse or promote products derived from this software 221573Srgrimes * without specific prior written permission. 231573Srgrimes * 241573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341573Srgrimes * SUCH DAMAGE. 3555837Sjasone * 3655837Sjasone * $FreeBSD: head/lib/libc/stdio/fdopen.c 56698 2000-01-27 23:07:25Z jasone $ 371573Srgrimes */ 381573Srgrimes 391573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 401573Srgrimesstatic char sccsid[] = "@(#)fdopen.c 8.1 (Berkeley) 6/4/93"; 411573Srgrimes#endif /* LIBC_SCCS and not lint */ 421573Srgrimes 431573Srgrimes#include <sys/types.h> 441573Srgrimes#include <fcntl.h> 451573Srgrimes#include <unistd.h> 461573Srgrimes#include <stdio.h> 471573Srgrimes#include <errno.h> 481573Srgrimes#include "local.h" 491573Srgrimes 501573SrgrimesFILE * 511573Srgrimesfdopen(fd, mode) 521573Srgrimes int fd; 531573Srgrimes const char *mode; 541573Srgrimes{ 551573Srgrimes register FILE *fp; 561573Srgrimes static int nofile; 571573Srgrimes int flags, oflags, fdflags, tmp; 581573Srgrimes 591573Srgrimes if (nofile == 0) 601573Srgrimes nofile = getdtablesize(); 611573Srgrimes 621573Srgrimes if ((flags = __sflags(mode, &oflags)) == 0) 631573Srgrimes return (NULL); 641573Srgrimes 651573Srgrimes /* Make sure the mode the user wants is a subset of the actual mode. */ 6656698Sjasone if ((fdflags = _fcntl(fd, F_GETFL, 0)) < 0) 671573Srgrimes return (NULL); 681573Srgrimes tmp = fdflags & O_ACCMODE; 691573Srgrimes if (tmp != O_RDWR && (tmp != (oflags & O_ACCMODE))) { 701573Srgrimes errno = EINVAL; 711573Srgrimes return (NULL); 721573Srgrimes } 731573Srgrimes 741573Srgrimes if ((fp = __sfp()) == NULL) 751573Srgrimes return (NULL); 761573Srgrimes fp->_flags = flags; 771573Srgrimes /* 781573Srgrimes * If opened for appending, but underlying descriptor does not have 791573Srgrimes * O_APPEND bit set, assert __SAPP so that __swrite() will lseek to 801573Srgrimes * end before each write. 811573Srgrimes */ 821573Srgrimes if ((oflags & O_APPEND) && !(fdflags & O_APPEND)) 831573Srgrimes fp->_flags |= __SAPP; 841573Srgrimes fp->_file = fd; 851573Srgrimes fp->_cookie = fp; 861573Srgrimes fp->_read = __sread; 871573Srgrimes fp->_write = __swrite; 881573Srgrimes fp->_seek = __sseek; 891573Srgrimes fp->_close = __sclose; 901573Srgrimes return (fp); 911573Srgrimes} 92