4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync/** @file
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Implementation of internal file buffer allocation functions.
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: makebuf.c,v 1.14 2003/08/07 16:43:28 agc Exp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync makebuf.c 8.1 (Berkeley) 6/4/93
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync**/
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <LibConfig.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include "namespace.h"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <sys/types.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <sys/stat.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <assert.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <stdio.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <stdlib.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <unistd.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include "reentrant.h"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include "local.h"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync#include <MainData.h>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync/*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Allocate a file buffer, or switch to unbuffered I/O.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Per the ANSI C standard, ALL tty devices default to line buffered.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * optimisation) right after the fstat() that finds the buffer size.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncvoid
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync__smakebuf(FILE *fp)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync{
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync void *p;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync int flags;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync size_t size;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync int couldbetty;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(fp != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (fp != NULL) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (fp->_flags & __SNBF) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._base = fp->_p = fp->_nbuf;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._size = 1;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync flags = __swhatbuf(fp, &size, &couldbetty);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if ((p = malloc(size)) == NULL) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_flags |= __SNBF;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._base = fp->_p = fp->_nbuf;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._size = 1;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync gMD->cleanup = _cleanup;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync flags |= __SMBF;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._base = fp->_p = p;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_bf._size = (int)size;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (couldbetty || isatty(fp->_file))
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync flags |= __SLBF;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_flags |= flags;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync}
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync/*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Internal routine to determine `proper' buffering for a file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncint
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync__swhatbuf(FILE *fp, size_t *bufsize, int *couldbetty)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync{
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync struct stat st;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(fp != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(bufsize != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync _DIAGASSERT(couldbetty != NULL);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if(fp == NULL) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (__SNPT);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (fp->_file < 0 || fstat(fp->_file, &st) < 0) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *couldbetty = 0;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *bufsize = BUFSIZ;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (__SNPT);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /* could be a tty iff it is a character device */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *couldbetty = S_ISCHR(st.st_mode);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if (st.st_blksize == 0) {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *bufsize = BUFSIZ;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return (__SNPT);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /*
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * Optimise fseek() only if it is a regular file. (The test for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * __sseek is mainly paranoia.) It is safe to set _blksize
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync * unconditionally; it will only be used if __SOPT is also set.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync *bufsize = st.st_blksize;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fp->_blksize = st.st_blksize;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync return ((st.st_mode & S_IFMT) == S_IFREG && fp->_seek == __sseek ?
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync __SOPT : __SNPT);
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync}