Home | History | Annotate | Line # | Download | only in stdio
stdio.c revision 1.11 
      1 /*	$NetBSD: stdio.c,v 1.11 1999/09/20 04:39:33 lukem 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[] = "@(#)stdio.c	8.1 (Berkeley) 6/4/93";
     43 #else
     44 __RCSID("$NetBSD: stdio.c,v 1.11 1999/09/20 04:39:33 lukem Exp $");
     45 #endif
     46 #endif /* LIBC_SCCS and not lint */
     47 
     48 #include "namespace.h"
     49 
     50 #include <assert.h>
     51 #include <errno.h>
     52 #include <fcntl.h>
     53 #include <stdio.h>
     54 #include <unistd.h>
     55 
     56 #include "local.h"
     57 
     58 /*
     59  * Small standard I/O/seek/close functions.
     60  * These maintain the `known seek offset' for seek optimisation.
     61  */
     62 int
     63 __sread(cookie, buf, n)
     64 	void *cookie;
     65 	char *buf;
     66 	int n;
     67 {
     68 	FILE *fp = cookie;
     69 	int ret;
     70 
     71 	_DIAGASSERT(fp != NULL);
     72 	_DIAGASSERT(buf != NULL);
     73 
     74 	ret = read(fp->_file, buf, (size_t)n);
     75 	/* if the read succeeded, update the current offset */
     76 	if (ret >= 0)
     77 		fp->_offset += ret;
     78 	else
     79 		fp->_flags &= ~__SOFF;	/* paranoia */
     80 	return (ret);
     81 }
     82 
     83 int
     84 __swrite(cookie, buf, n)
     85 	void *cookie;
     86 	char const *buf;
     87 	int n;
     88 {
     89 	FILE *fp = cookie;
     90 
     91 	_DIAGASSERT(cookie != NULL);
     92 	_DIAGASSERT(buf != NULL);
     93 
     94 	if (fp->_flags & __SAPP)
     95 		(void) lseek(fp->_file, (off_t)0, SEEK_END);
     96 	fp->_flags &= ~__SOFF;	/* in case FAPPEND mode is set */
     97 	return (write(fp->_file, buf, (size_t)n));
     98 }
     99 
    100 fpos_t
    101 __sseek(cookie, offset, whence)
    102 	void *cookie;
    103 	fpos_t offset;
    104 	int whence;
    105 {
    106 	FILE *fp = cookie;
    107 	off_t ret;
    108 
    109 	_DIAGASSERT(fp != NULL);
    110 
    111 	ret = lseek(fp->_file, (off_t)offset, whence);
    112 	if (ret == -1L)
    113 		fp->_flags &= ~__SOFF;
    114 	else {
    115 		fp->_flags |= __SOFF;
    116 		fp->_offset = ret;
    117 	}
    118 	return (ret);
    119 }
    120 
    121 int
    122 __sclose(cookie)
    123 	void *cookie;
    124 {
    125 
    126 	_DIAGASSERT(cookie != NULL);
    127 
    128 	return (close(((FILE *)cookie)->_file));
    129 }
    130