root / prex-0.9.0 / usr / lib / libc / stdio / wsetup.c @ 03e9c04a
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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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*
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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 <stdio.h> |
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#include <stdlib.h> |
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#include "local.h" |
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/*
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* Various output routines call wsetup to be sure it is safe to write,
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* because either _flags does not include __SWR, or _buf is NULL.
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* _wsetup returns 0 if OK to write, nonzero otherwise.
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*/
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int
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__swsetup(fp) |
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FILE *fp; |
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{ |
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/* make sure stdio is set up */
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if (!__sdidinit)
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__sinit(); |
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/*
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* If we are not writing, we had better be reading and writing.
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*/
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if ((fp->_flags & __SWR) == 0) { |
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if ((fp->_flags & __SRW) == 0) |
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return (EOF); |
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if (fp->_flags & __SRD) {
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/* clobber any ungetc data */
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if (HASUB(fp))
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FREEUB(fp); |
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fp->_flags &= ~(__SRD|__SEOF); |
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fp->_r = 0;
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fp->_p = fp->_bf._base; |
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} |
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fp->_flags |= __SWR; |
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} |
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/*
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* Make a buffer if necessary, then set _w.
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*/
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if (fp->_bf._base == NULL) |
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__smakebuf(fp); |
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fp->_w = fp->_flags & (__SNBF|__SLBF) ? 0 : fp->_bf._size;
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return (0); |
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} |