4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync/** @file
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Implementation of fgets as declared in <stdio.h>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This program and the accompanying materials are licensed and made available
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync under the terms and conditions of the BSD License that accompanies this
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync distribution. The full text of the license may be found at
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync http://opensource.org/licenses/bsd-license.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Copyright (c) 1990, 1993
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The Regents of the University of California. All rights reserved.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This code is derived from software contributed to Berkeley by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Chris Torek.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Redistribution and use in source and binary forms, with or without
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync modification, are permitted provided that the following conditions
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync are met:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync - Redistributions of source code must retain the above copyright
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync notice, this list of conditions and the following disclaimer.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync - Redistributions in binary form must reproduce the above copyright
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync notice, this list of conditions and the following disclaimer in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync documentation and/or other materials provided with the distribution.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync - Neither the name of the University nor the names of its contributors
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync may be used to endorse or promote products derived from this software
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync without specific prior written permission.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync POSSIBILITY OF SUCH DAMAGE.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync NetBSD: fgets.c,v 1.20 2003/12/14 23:56:28 lukem Exp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fgets.c 8.2 (Berkeley) 12/22/93
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync**/
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <LibConfig.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <assert.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <stdio.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <string.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <errno.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include "reentrant.h"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include "local.h"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync/*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Read at most n-1 characters from the given file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Stop when a newline has been read, or the count runs out.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Return first argument, or NULL if no characters were read.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncchar *
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncfgets(char *buf, int n, FILE *fp)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync{
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync size_t len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync char *s;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync unsigned char *p, *t;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(buf != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(fp != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if ((fp == NULL) || (n <= 0)) { /* sanity check */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync errno = EINVAL;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync FLOCKFILE(fp);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _SET_ORIENTATION(fp, -1);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync s = buf;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync n--; /* leave space for NUL */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync while (n != 0) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * If the buffer is empty, refill it.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (fp->_r <= 0) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (__srefill(fp)) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /* EOF/error: stop with partial or no line */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (s == buf) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync FUNLOCKFILE(fp);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync break;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync len = fp->_r;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync p = fp->_p;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Scan through at most n bytes of the current buffer,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * looking for '\n'. If found, copy up to and including
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * newline, and stop. Otherwise, copy entire chunk
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * and loop.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (len > (size_t)n)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync len = n;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync t = memchr((void *)p, '\n', len);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (t != NULL) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync len = ++t - p;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_r -= (int)len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_p = t;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (void)memcpy((void *)s, (void *)p, len);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync s[len] = 0;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync FUNLOCKFILE(fp);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (buf);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_r -= (int)len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_p += len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (void)memcpy((void *)s, (void *)p, len);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync s += len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync n -= (int)len;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *s = 0;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync FUNLOCKFILE(fp);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (buf);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync}