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/* $OpenBSD: vsnprintf.c,v 1.16 2015/08/31 02:53:57 guenther Exp $ */ |
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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 <limits.h> |
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#include <stdio.h> |
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#include <string.h> |
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#include "local.h" |
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int |
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vsnprintf(char *str, size_t n, const char *fmt, __va_list ap) |
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{ |
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int ret; |
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char dummy; |
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FILE f; |
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struct __sfileext fext; |
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_FILEEXT_SETUP(&f, &fext); |
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/* While snprintf(3) specifies size_t stdio uses an int internally */ |
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if (n > INT_MAX) |
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n = INT_MAX; |
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/* Stdio internals do not deal correctly with zero length buffer */ |
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if (n == 0) { |
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str = &dummy; |
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n = 1; |
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} |
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f._file = -1; |
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f._flags = __SWR | __SSTR; |
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f._bf._base = f._p = (unsigned char *)str; |
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f._bf._size = f._w = n - 1; |
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ret = __vfprintf(&f, fmt, ap); |
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*f._p = '\0'; |
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return (ret); |
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} |
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DEF_STRONG(vsnprintf); |