mirror of
https://gitlab.freedesktop.org/libbsd/libbsd.git
synced 2025-10-25 02:06:07 +02:00
cb7bc0d85e
This avoids buffer overwrites during concurrent or intermixed calls to fgetln() when using more than one different stream (currently 32), which the original interface supports natively by using an internal buffer from the FILE structure. Although this workaround is rudimentary, it should cover most of the theoretically problematic cases.
74 lines
2.4 KiB
C
74 lines
2.4 KiB
C
/*
|
|
* Copyright © 2005 Hector Garcia Alvarez
|
|
* Copyright © 2005, 2008-2012 Guillem Jover <guillem@hadrons.org>
|
|
*
|
|
* 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.
|
|
* 3. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <sys/cdefs.h>
|
|
#include <sys/types.h>
|
|
#include <string.h>
|
|
|
|
#ifdef HAVE_GETLINE
|
|
struct filebuf {
|
|
FILE *fp;
|
|
char *buf;
|
|
size_t len;
|
|
};
|
|
|
|
#define FILEBUF_POOL_ITEMS 32
|
|
|
|
static struct filebuf fb_pool[FILEBUF_POOL_ITEMS];
|
|
static int fb_pool_cur;
|
|
|
|
char *
|
|
fgetln(FILE *stream, size_t *len)
|
|
{
|
|
struct filebuf *fb;
|
|
ssize_t nread;
|
|
|
|
/* Try to diminish the possibility of several fgetln() calls being
|
|
* used on different streams, by using a pool of buffers per file. */
|
|
fb = &fb_pool[fb_pool_cur];
|
|
if (fb->fp != stream && fb->fp != NULL) {
|
|
fb_pool_cur++;
|
|
fb_pool_cur %= FILEBUF_POOL_ITEMS;
|
|
fb = &fb_pool[fb_pool_cur];
|
|
}
|
|
fb->fp = stream;
|
|
|
|
nread = getline(&fb->buf, &fb->len, stream);
|
|
/* Note: the getdelim/getline API ensures nread != 0. */
|
|
if (nread == -1) {
|
|
*len = 0;
|
|
return NULL;
|
|
} else {
|
|
*len = (size_t)nread;
|
|
return fb->buf;
|
|
}
|
|
}
|
|
#else
|
|
#error "Function fgetln() needs to be ported."
|
|
#endif
|