From f4c589ff6c653d1d2a09c26e46ead3c8a15655d8 Mon Sep 17 00:00:00 2001 From: "bk@work.mysql.com" <> Date: Mon, 31 Jul 2000 21:29:14 +0200 Subject: Import changeset --- mit-pthreads/stdio/setvbuf.c | 154 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 mit-pthreads/stdio/setvbuf.c (limited to 'mit-pthreads/stdio/setvbuf.c') diff --git a/mit-pthreads/stdio/setvbuf.c b/mit-pthreads/stdio/setvbuf.c new file mode 100644 index 00000000000..288d8c32db0 --- /dev/null +++ b/mit-pthreads/stdio/setvbuf.c @@ -0,0 +1,154 @@ +/*- + * Copyright (c) 1990 The Regents of the University of California. + * Copyright (c) 1993, 1994 Chris Provenzano. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Chris Torek. + * + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +/*static char *sccsid = "from: @(#)setvbuf.c 5.5 (Berkeley) 5/6/93";*/ +static char *rcsid = "$Id$"; +#endif /* LIBC_SCCS and not lint */ + +#include +#include +#include +#include "local.h" + +/* + * Set one of the three kinds of buffering, optionally including + * a buffer. + */ +setvbuf(fp, buf, mode, size) + register FILE *fp; + char *buf; + register int mode; + register size_t size; +{ + register int ret, flags; + size_t iosize; + int ttyflag; + + /* + * Verify arguments. The `int' limit on `size' is due to this + * particular implementation. Note, buf and size are ignored + * when setting _IONBF. + */ + if (mode != _IONBF) + if ((mode != _IOFBF && mode != _IOLBF) || (int)size < 0) + return (EOF); + + flockfile(fp); + /* + * Write current buffer, if any. Discard unread input, cancel + * line buffering, and free old buffer if malloc()ed. + */ + ret = 0; + (void)__sflush(fp); + fp->_r = fp->_lbfsize = 0; + flags = fp->_flags; + if (flags & __SMBF) + free((void *)fp->_bf._base); + flags &= ~(__SLBF | __SNBF | __SMBF | __SOPT | __SNPT); + + /* If setting unbuffered mode, skip all the hard work. */ + if (mode == _IONBF) + goto nbf; + + /* + * Find optimal I/O size for seek optimization. This also returns + * a `tty flag' to suggest that we check isatty(fd), but we do not + * care since our caller told us how to buffer. + */ + flags |= __swhatbuf(fp, &iosize, &ttyflag); + if (size == 0) { + buf = NULL; /* force local allocation */ + size = iosize; + } + + /* Allocate buffer if needed. */ + if (buf == NULL) { + if ((buf = malloc(size)) == NULL) { + /* + * Unable to honor user's request. We will return + * failure, but try again with file system size. + */ + ret = EOF; + if (size != iosize) { + size = iosize; + buf = malloc(size); + } + } + if (buf == NULL) { + /* No luck; switch to unbuffered I/O. */ +nbf: + fp->_flags = flags | __SNBF; + fp->_w = 0; + fp->_bf._base = fp->_p = fp->_nbuf; + fp->_bf._size = 1; + funlockfile(fp); + return (ret); + } + flags |= __SMBF; + } + + /* + * Kill any seek optimization if the buffer is not the + * right size. + * + * SHOULD WE ALLOW MULTIPLES HERE (i.e., ok iff (size % iosize) == 0)? + */ + if (size != iosize) + flags |= __SNPT; + + /* + * Fix up the FILE fields, and set __cleanup for output flush on + * exit (since we are buffered in some way). If in r/w mode, go + * to the intermediate state, so that everyone has to call + * __srefill or __swsetup on the first operation -- it is more + * trouble than it is worth to set things up correctly here. + */ + if (mode == _IOLBF) + flags |= __SLBF; + if (flags & __SRW) + flags &= ~(__SRD | __SWR); + fp->_w = size; /* Was 0 (mevans) */ + fp->_flags = flags; + fp->_bf._base = fp->_p = (unsigned char *)buf; + fp->_bf._size = size; + fp->_lbfsize = 0; + __cleanup = _cleanup; + + funlockfile(fp); + return (ret); +} -- cgit v1.2.1