minix/lib/libc/other/fgetln.c

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/* $NetBSD: fgetln.c,v 1.5 2008/04/29 05:46:08 martin Exp $ */
/*-
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
/*
* XXX: This implementation doesn't quite conform to the specification
* in the man page, in that it only manages one buffer at all, not one
* per stdio stream. Since the previous implementation did the same,
* this won't break anything new.
*/
char *
fgetln(fp, len)
FILE *fp;
size_t *len;
{
static char *buf = NULL;
static size_t bufsiz = 0;
static size_t buflen = 0;
int c;
if (buf == NULL) {
bufsiz = BUFSIZ;
if ((buf = malloc(bufsiz)) == NULL)
return NULL;
}
buflen = 0;
while ((c = fgetc(fp)) != EOF) {
if (buflen >= bufsiz) {
size_t nbufsiz = bufsiz + BUFSIZ;
char *nbuf = realloc(buf, nbufsiz);
if (nbuf == NULL) {
int oerrno = errno;
free(buf);
errno = oerrno;
buf = NULL;
return NULL;
}
buf = nbuf;
bufsiz = nbufsiz;
}
buf[buflen++] = c;
if (c == '\n')
break;
}
*len = buflen;
return buflen == 0 ? NULL : buf;
}