xref: /freebsd/tools/build/cross-build/fgetln_fallback.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*
2  * Copyright © 2005 Hector Garcia Alvarez
3  * Copyright © 2005, 2008-2012 Guillem Jover <guillem@hadrons.org>
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
18  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
19  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <stdio.h>
29 
30 #include <sys/types.h>
31 #include <string.h>
32 
33 #include "local-link.h"
34 
35 #define HAVE_GETLINE 1
36 #ifdef HAVE_GETLINE
37 struct filebuf {
38 	FILE *fp;
39 	char *buf;
40 	size_t len;
41 };
42 
43 #define FILEBUF_POOL_ITEMS 32
44 
45 static struct filebuf fb_pool[FILEBUF_POOL_ITEMS];
46 static int fb_pool_cur;
47 
48 char *
49 fgetln(FILE *stream, size_t *len)
50 {
51 	struct filebuf *fb;
52 	ssize_t nread;
53 
54 	flockfile(stream);
55 
56 	/* Try to diminish the possibility of several fgetln() calls being
57 	 * used on different streams, by using a pool of buffers per file. */
58 	fb = &fb_pool[fb_pool_cur];
59 	if (fb->fp != stream && fb->fp != NULL) {
60 		fb_pool_cur++;
61 		fb_pool_cur %= FILEBUF_POOL_ITEMS;
62 		fb = &fb_pool[fb_pool_cur];
63 	}
64 	fb->fp = stream;
65 
66 	nread = getline(&fb->buf, &fb->len, stream);
67 
68 	funlockfile(stream);
69 
70 	/* Note: the getdelim/getline API ensures nread != 0. */
71 	if (nread == -1) {
72 		*len = 0;
73 		return NULL;
74 	} else {
75 		*len = (size_t)nread;
76 		return fb->buf;
77 	}
78 }
79 libbsd_link_warning(fgetln,
80                     "This function cannot be safely ported, use getline(3) "
81                     "instead, as it is supported by GNU and POSIX.1-2008.")
82 #else
83 #error "Function fgetln() needs to be ported."
84 #endif
85