getline.c revision 276415 
1/*	$NetBSD: getline.c,v 1.2 2014/09/16 17:23:50 christos Exp $	*/
2
3/*-
4 * Copyright (c) 2011 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas.
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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include "file.h"
33#if !HAVE_GETLINE
34#include <stdlib.h>
35#include <stdio.h>
36#include <unistd.h>
37#include <errno.h>
38#include <string.h>
39
40public ssize_t
41getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp)
42{
43	char *ptr, *eptr;
44
45
46	if (*buf == NULL || *bufsiz == 0) {
47		*bufsiz = BUFSIZ;
48		if ((*buf = malloc(*bufsiz)) == NULL)
49			return -1;
50	}
51
52	for (ptr = *buf, eptr = *buf + *bufsiz;;) {
53		int c = fgetc(fp);
54		if (c == -1) {
55			if (feof(fp)) {
56				ssize_t diff = (ssize_t)(ptr - *buf);
57				if (diff != 0) {
58					*ptr = '\0';
59					return diff;
60				}
61			}
62			return -1;
63		}
64		*ptr++ = c;
65		if (c == delimiter) {
66			*ptr = '\0';
67			return ptr - *buf;
68		}
69		if (ptr + 2 >= eptr) {
70			char *nbuf;
71			size_t nbufsiz = *bufsiz * 2;
72			ssize_t d = ptr - *buf;
73			if ((nbuf = realloc(*buf, nbufsiz)) == NULL)
74				return -1;
75			*buf = nbuf;
76			*bufsiz = nbufsiz;
77			eptr = nbuf + nbufsiz;
78			ptr = nbuf + d;
79		}
80	}
81}
82
83ssize_t
84getline(char **buf, size_t *bufsiz, FILE *fp)
85{
86	return getdelim(buf, bufsiz, '\n', fp);
87}
88
89#endif
90
91#ifdef TEST
92int
93main(int argc, char *argv[])
94{
95	char *p = NULL;
96	ssize_t len;
97	size_t n = 0;
98
99	while ((len = getline(&p, &n, stdin)) != -1)
100		(void)printf("%" SIZE_T_FORMAT "d %s", len, p);
101	free(p);
102	return 0;
103}
104#endif
105