a77546fbb3
This implements the gets_s(3) function as documented at http://en.cppreference.com/w/c/io/gets. It facilitates the optional removal of gets(3). Reviewed by: ed MFC after: 2 weeks Relnotes: yes Differential Revision: https://reviews.freebsd.org/D12785
103 lines
3.0 KiB
C
103 lines
3.0 KiB
C
/*-
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* SPDX-License-Identifier: BSD-3-Clause
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*
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* Copyright (c) 1990, 1993
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* The Regents of the University of California. All rights reserved.
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* Copyright (c) 2017, 2018
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* Cyril S. E. Schubert. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Chris Torek.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "namespace.h"
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#include <errno.h>
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#include <unistd.h>
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#include <stdint.h>
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#include <stdio.h>
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#include "un-namespace.h"
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#include "libc_private.h"
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#include "local.h"
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static inline char *
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_gets_s(char *buf, rsize_t n)
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{
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int c;
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char *s;
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ORIENT(stdin, -1);
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for (s = buf, n--; (c = __sgetc(stdin)) != '\n' && n > 0 ; n--) {
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if (c == EOF) {
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if (s == buf) {
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return (NULL);
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} else
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break;
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} else
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*s++ = c;
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}
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/*
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* If end of buffer reached, discard until \n or eof.
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* Then throw an error.
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*/
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if (n == 0) {
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/* discard */
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while ((c = __sgetc(stdin)) != '\n' && c != EOF);
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/* throw the error after lock released prior to exit */
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__throw_constraint_handler_s("gets_s : end of buffer", E2BIG);
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return (NULL);
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}
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*s = 0;
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return (buf);
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}
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/* ISO/IEC 9899:2011 K.3.7.4.1 */
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char *
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gets_s(char *buf, rsize_t n)
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{
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char *ret;
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if (buf == NULL) {
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__throw_constraint_handler_s("gets_s : str is NULL", EINVAL);
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return(NULL);
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} else if (n > RSIZE_MAX) {
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__throw_constraint_handler_s("gets_s : n > RSIZE_MAX",
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EINVAL);
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return(NULL);
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} else if (n == 0) {
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__throw_constraint_handler_s("gets_s : n == 0", EINVAL);
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return(NULL);
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}
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FLOCKFILE_CANCELSAFE(stdin);
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ret = _gets_s(buf, n);
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FUNLOCKFILE_CANCELSAFE();
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return (ret);
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}
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