1 /*
2  * Copyright (c) 2015 Joerg Jung <jung@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /*
18  * portable fgetln() version, NOT reentrant
19  */
20 
21 #include "openbsd-compat.h"
22 
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <errno.h>
26 
27 void *reallocarray(void *, size_t, size_t);
28 
29 char *
30 fgetln(FILE *fp, size_t *len)
31 {
32 	static char *buf = NULL;
33 	static size_t bufsz = 0;
34 	size_t r = 0;
35 	char *p;
36 	int c, e;
37 
38 	if (buf == NULL) {
39 		if ((buf = calloc(1, BUFSIZ)) == NULL)
40 			return NULL;
41 		bufsz = BUFSIZ;
42 	}
43 
44 	while ((c = getc(fp)) != EOF) {
45 		buf[r++] = c;
46 		if (r == bufsz) {
47 			if (!(p = reallocarray(buf, 2, bufsz))) {
48 				e = errno;
49 				free(buf);
50 				errno = e;
51 				buf = NULL, bufsz = 0;
52 				return NULL;
53 			}
54 			buf = p, bufsz = 2 * bufsz;
55 		}
56 		if (c == '\n')
57 			break;
58 	}
59 	return (*len = r) ? buf : NULL;
60 }
61