Annotation of prex/usr/lib/libc/stdio/findfp.c, Revision 1.1
1.1 ! nbrk 1: /*-
! 2: * Copyright (c) 1990, 1993
! 3: * The Regents of the University of California. All rights reserved.
! 4: *
! 5: * This code is derived from software contributed to Berkeley by
! 6: * Chris Torek.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: */
! 32:
! 33: #include <sys/param.h>
! 34: #include <unistd.h>
! 35: #include <stdio.h>
! 36: #include <stdlib.h>
! 37: #include <errno.h>
! 38: #include <string.h>
! 39: #include "local.h"
! 40:
! 41: int __sdidinit;
! 42:
! 43: #define std(next, flags, file) \
! 44: {next,NULL,0,0,flags,file,{0,0},{0,0},NULL,0,{0},{0}}
! 45: /* p r w flags file _bf z */
! 46:
! 47: FILE __sF[3] = {
! 48: std(&__sF[1], __SRD, STDIN_FILENO),
! 49: std(&__sF[2], __SWR, STDOUT_FILENO),
! 50: std(NULL, __SWR|__SNBF, STDERR_FILENO)
! 51: };
! 52:
! 53: /*
! 54: * Find a free FILE for fopen et al.
! 55: */
! 56: FILE *
! 57: __sfp()
! 58: {
! 59: FILE *fp, *tmp;
! 60:
! 61: if (!__sdidinit)
! 62: __sinit();
! 63: for (fp = &__sF[0];; fp = fp->next) {
! 64: if (fp->_flags == 0)
! 65: goto found;
! 66: if (fp->next == NULL) {
! 67: if ((tmp = malloc(sizeof(FILE))) == NULL)
! 68: break;
! 69: tmp->next = NULL;
! 70: fp->next = tmp;
! 71: fp = tmp;
! 72: goto found;
! 73: }
! 74: }
! 75: return (NULL);
! 76: found:
! 77: fp->_flags = 1; /* reserve this slot; caller sets real flags */
! 78: fp->_p = NULL; /* no current pointer */
! 79: fp->_w = 0; /* nothing to read or write */
! 80: fp->_r = 0;
! 81: fp->_bf._base = NULL; /* no buffer */
! 82: fp->_bf._size = 0;
! 83: fp->_file = -1; /* no file */
! 84: fp->_ub._base = NULL; /* no ungetc buffer */
! 85: fp->_ub._size = 0;
! 86: return (fp);
! 87: }
! 88:
! 89: /*
! 90: * exit() calls _cleanup() through *__cleanup, set whenever we
! 91: * open or buffer a file. This chicanery is done so that programs
! 92: * that do not use stdio need not link it all in.
! 93: *
! 94: * The name `_cleanup' is, alas, fairly well known outside stdio.
! 95: b */
! 96: void
! 97: _cleanup()
! 98: {
! 99: /* (void) _fwalk(fclose); */
! 100: (void) _fwalk(__sflush); /* `cheating' */
! 101: }
! 102:
! 103: /*
! 104: * __sinit() is called whenever stdio's internal variables must be set up.
! 105: */
! 106: void
! 107: __sinit()
! 108: {
! 109: /* make sure we clean up on exit */
! 110: __cleanup = _cleanup; /* conservative */
! 111: __sdidinit = 1;
! 112: }
CVSweb