xref: /freebsd/contrib/file/src/getline.c (revision 5608fd23c27fa1e8ee595d7b678cbfd35d657fbe)
1 /*	$NetBSD: fgetln.c,v 1.9 2008/04/29 06:53:03 martin 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 
40 public ssize_t
41 getdelim(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 				return ptr == *buf ? -1 : ptr - *buf;
57 			else
58 				return -1;
59 		}
60 		*ptr++ = c;
61 		if (c == delimiter) {
62 			*ptr = '\0';
63 			return ptr - *buf;
64 		}
65 		if (ptr + 2 >= eptr) {
66 			char *nbuf;
67 			size_t nbufsiz = *bufsiz * 2;
68 			ssize_t d = ptr - *buf;
69 			if ((nbuf = realloc(*buf, nbufsiz)) == NULL)
70 				return -1;
71 			*buf = nbuf;
72 			*bufsiz = nbufsiz;
73 			eptr = nbuf + nbufsiz;
74 			ptr = nbuf + d;
75 		}
76 	}
77 }
78 
79 ssize_t
80 getline(char **buf, size_t *bufsiz, FILE *fp)
81 {
82 	return getdelim(buf, bufsiz, '\n', fp);
83 }
84 
85 #endif
86 
87 #ifdef TEST
88 int
89 main(int argc, char *argv[])
90 {
91 	char *p = NULL;
92 	ssize_t len;
93 	size_t n = 0;
94 
95 	while ((len = getline(&p, &n, stdin)) != -1)
96 		(void)printf("%zd %s", len, p);
97 	free(p);
98 	return 0;
99 }
100 #endif
101