iolog_gets.c

/*
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 2009-2021 Todd C. Miller <[email protected]>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STDBOOL_H
# include <stdbool.h>
#else
# include <compat/stdbool.h>
#endif
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <time.h>

#include <sudo_compat.h>
#include <sudo_debug.h>
#include <sudo_iolog.h>

/*
 * Like fgets() but for struct iolog_file.
 */
char *
iolog_gets(struct iolog_file *iol, char *buf, int bufsize,
    const char **errstr)
{
    char *str;
    debug_decl(iolog_gets, SUDO_DEBUG_UTIL);

    if (bufsize < 0) {
	errno = EINVAL;
	if (errstr != NULL)
	    *errstr = strerror(errno);
	debug_return_str(NULL);
    }

#ifdef HAVE_ZLIB_H
    if (iol->compressed) {
	if ((str = gzgets(iol->fd.g, buf, bufsize)) == NULL) {
	    if (errstr != NULL) {
		int errnum;
		*errstr = gzerror(iol->fd.g, &errnum);
		if (errnum == Z_ERRNO)
		    *errstr = strerror(errno);
	    }
	}
    } else
#endif
    {
	if ((str = fgets(buf, bufsize, iol->fd.f)) == NULL) {
	    if (errstr != NULL)
		*errstr = strerror(errno);
	}
    }
    debug_return_str(str);
}