fgetln.c

/*      $NetBSD: fgetln.c,v 1.9 2008/04/29 06:53:03 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.
 */

#ifdef HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#else
#include "config.h"
#endif

#if !HAVE_FGETLN
#include <stdlib.h>
#ifndef HAVE_NBTOOL_CONFIG_H
/* These headers are required, but included from nbtool_config.h */
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#endif

char *
fgetln(FILE *fp, size_t *len)
{
        static char *buf = NULL;
        static size_t bufsiz = 0;
        char *ptr;


        if (buf == NULL) {
                bufsiz = BUFSIZ;
                if ((buf = malloc(bufsiz)) == NULL)
                        return NULL;
        }

        if (fgets(buf, bufsiz, fp) == NULL)
                return NULL;

        *len = 0;
        while ((ptr = strchr(&buf[*len], '\n')) == NULL) {
                size_t nbufsiz = bufsiz + BUFSIZ;
                char *nbuf = realloc(buf, nbufsiz);

                if (nbuf == NULL) {
                        int oerrno = errno;
                        free(buf);
                        errno = oerrno;
                        buf = NULL;
                        return NULL;
                } else
                        buf = nbuf;

                if (fgets(&buf[bufsiz], BUFSIZ, fp) == NULL) {
                        buf[bufsiz] = '\0';
                        *len = strlen(buf);
                        return buf;
                }

                *len = bufsiz;
                bufsiz = nbufsiz;
        }

        *len = (ptr - buf) + 1;
        return buf;
}

#endif

#ifdef TEST
int
main(int argc, char *argv[])
{
        char *p;
        size_t len;

        while ((p = fgetln(stdin, &len)) != NULL) {
                (void)printf("%zu %s", len, p);
                free(p);
        }
        return 0;
}
#endif