xref: /onnv-gate/usr/src/lib/libc/port/stdio/fgets.c (revision 6812:febeba71273d)
10Sstevel@tonic-gate /*
20Sstevel@tonic-gate  * CDDL HEADER START
30Sstevel@tonic-gate  *
40Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*6812Sraf  * Common Development and Distribution License (the "License").
6*6812Sraf  * You may not use this file except in compliance with the License.
70Sstevel@tonic-gate  *
80Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
90Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
100Sstevel@tonic-gate  * See the License for the specific language governing permissions
110Sstevel@tonic-gate  * and limitations under the License.
120Sstevel@tonic-gate  *
130Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
140Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
150Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
160Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
170Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
180Sstevel@tonic-gate  *
190Sstevel@tonic-gate  * CDDL HEADER END
200Sstevel@tonic-gate  */
21*6812Sraf 
220Sstevel@tonic-gate /*
23*6812Sraf  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
240Sstevel@tonic-gate  * Use is subject to license terms.
250Sstevel@tonic-gate  */
260Sstevel@tonic-gate 
270Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
280Sstevel@tonic-gate /*	  All Rights Reserved  	*/
290Sstevel@tonic-gate 
30*6812Sraf #pragma ident	"%Z%%M%	%I%	%E% SMI"
310Sstevel@tonic-gate 
32*6812Sraf #include "lint.h"
330Sstevel@tonic-gate #include "file64.h"
340Sstevel@tonic-gate #include "mtlib.h"
350Sstevel@tonic-gate #include <stdio.h>
360Sstevel@tonic-gate #include <memory.h>
370Sstevel@tonic-gate #include <errno.h>
380Sstevel@tonic-gate #include <thread.h>
390Sstevel@tonic-gate #include <synch.h>
400Sstevel@tonic-gate #include <sys/types.h>
410Sstevel@tonic-gate #include "stdiom.h"
420Sstevel@tonic-gate #include "mse.h"
430Sstevel@tonic-gate 
440Sstevel@tonic-gate /* read size-max line from stream, including '\n' */
450Sstevel@tonic-gate char *
fgets(char * buf,int size,FILE * iop)460Sstevel@tonic-gate fgets(char *buf, int size, FILE *iop)
470Sstevel@tonic-gate {
480Sstevel@tonic-gate 	char *ptr = buf;
490Sstevel@tonic-gate 	int n;
500Sstevel@tonic-gate 	Uchar *bufend;
510Sstevel@tonic-gate 	char *p;
520Sstevel@tonic-gate 	rmutex_t *lk;
530Sstevel@tonic-gate 
540Sstevel@tonic-gate 	FLOCKFILE(lk, iop);
550Sstevel@tonic-gate 
560Sstevel@tonic-gate 	_SET_ORIENTATION_BYTE(iop);
570Sstevel@tonic-gate 
580Sstevel@tonic-gate 	if (!(iop->_flag & (_IOREAD | _IORW))) {
590Sstevel@tonic-gate 		errno = EBADF;
600Sstevel@tonic-gate 		FUNLOCKFILE(lk);
610Sstevel@tonic-gate 		return (NULL);
620Sstevel@tonic-gate 	}
630Sstevel@tonic-gate 
640Sstevel@tonic-gate 	if (iop->_base == NULL) {
650Sstevel@tonic-gate 		if ((bufend = _findbuf(iop)) == NULL) {
660Sstevel@tonic-gate 			FUNLOCKFILE(lk);
670Sstevel@tonic-gate 			return (NULL);
680Sstevel@tonic-gate 		}
690Sstevel@tonic-gate 	}
700Sstevel@tonic-gate 	else
710Sstevel@tonic-gate 		bufend = _bufend(iop);
720Sstevel@tonic-gate 
730Sstevel@tonic-gate 	size--;		/* room for '\0' */
740Sstevel@tonic-gate 	while (size > 0) {
750Sstevel@tonic-gate 		/* empty buffer */
760Sstevel@tonic-gate 		if (iop->_cnt <= 0) {
770Sstevel@tonic-gate 			if (__filbuf(iop) != EOF) {
780Sstevel@tonic-gate 				iop->_ptr--;	/* put back the character */
790Sstevel@tonic-gate 				iop->_cnt++;
800Sstevel@tonic-gate 			} else if (ptr == buf) {  /* never read anything */
810Sstevel@tonic-gate 				FUNLOCKFILE(lk);
820Sstevel@tonic-gate 				return (NULL);
830Sstevel@tonic-gate 			} else
840Sstevel@tonic-gate 				break;		/* nothing left to read */
850Sstevel@tonic-gate 		}
860Sstevel@tonic-gate 		n = (int)(size < iop->_cnt ? size : iop->_cnt);
870Sstevel@tonic-gate 		if ((p = memccpy(ptr, (char *)iop->_ptr, '\n',
880Sstevel@tonic-gate 		    (size_t)n)) != NULL)
890Sstevel@tonic-gate 			n = (int)(p - ptr);
900Sstevel@tonic-gate 		ptr += n;
910Sstevel@tonic-gate 		iop->_cnt -= n;
920Sstevel@tonic-gate 		iop->_ptr += n;
930Sstevel@tonic-gate 		if (_needsync(iop, bufend))
940Sstevel@tonic-gate 			_bufsync(iop, bufend);
950Sstevel@tonic-gate 		if (p != NULL)
960Sstevel@tonic-gate 			break; /* newline found */
970Sstevel@tonic-gate 		size -= n;
980Sstevel@tonic-gate 	}
990Sstevel@tonic-gate 	FUNLOCKFILE(lk);
1000Sstevel@tonic-gate 	*ptr = '\0';
1010Sstevel@tonic-gate 	return (buf);
1020Sstevel@tonic-gate }
103