scoutos / prex-0.9.0 / usr / lib / libc / stdio / findfp.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 <sys/param.h> |
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#include <unistd.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <errno.h> |
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#include <string.h> |
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#include "local.h" |
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int __sdidinit;
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FILE __sF[3];
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static void |
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std(FILE *fp, FILE *next, short flags, short fileno) |
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{ |
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memset(fp, 0, sizeof(FILE)); |
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fp->next = next; |
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fp->_flags = flags; |
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fp->_file = fileno; |
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} |
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/*
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* Find a free FILE for fopen et al.
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*/
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FILE * |
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__sfp() |
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{ |
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FILE *fp, *tmp; |
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if (!__sdidinit)
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__sinit(); |
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for (fp = &__sF[0];; fp = fp->next) { |
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if (fp->_flags == 0) |
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goto found;
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if (fp->next == NULL) { |
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if ((tmp = malloc(sizeof(FILE))) == NULL) |
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break;
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fp->next = tmp; |
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fp = tmp; |
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goto found;
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} |
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} |
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return (NULL); |
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found:
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std(fp, NULL, 1, -1); |
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return (fp);
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} |
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/*
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* exit() calls _cleanup() through *__cleanup, set whenever we
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* open or buffer a file. This chicanery is done so that programs
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* that do not use stdio need not link it all in.
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*
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* The name `_cleanup' is, alas, fairly well known outside stdio.
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b */
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void
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_cleanup() |
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{ |
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/* (void) _fwalk(fclose); */
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(void) _fwalk(__sflush); /* `cheating' */ |
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} |
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/*
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* __sinit() is called whenever stdio's internal variables must be set up.
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*/
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void
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__sinit() |
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{ |
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std(&__sF[0], &__sF[1], __SRD, STDIN_FILENO); |
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std(&__sF[1], &__sF[2], __SWR, STDOUT_FILENO); |
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std(&__sF[2], NULL, __SWR|__SNBF, STDERR_FILENO); |
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/* make sure we clean up on exit */
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__cleanup = _cleanup; /* conservative */
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__sdidinit = 1;
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} |