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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37//#include <sys/param.h> 38#include <unistd.h> 39#include <stdio.h> 40#include <errno.h> 41#include <stdlib.h> 42#include <string.h> 43 44#include <errno_private.h> 45 46#include "local.h" 47#include "glue.h" 48 49/* Prototype needed */ 50void f_prealloc(void); 51 52int __sdidinit; 53 54/* XXX - these belong in sys/param.h 55 * Round p (pointer or byte index) up to a correctly-aligned value 56 * for all data types (int, long, ...). The result is u_int and 57 * must be cast to any desired pointer type. 58 */ 59#define ALIGNBYTES (sizeof(int) - 1) 60#define ALIGN(p) (((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES) 61 62#define NDYNAMIC 10 /* add ten more whenever necessary */ 63 64#define std(flags, file) \ 65 {0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite} 66/* p r w flags file _bf z cookie close read seek write */ 67 68 /* the usual - (stdin + stdout + stderr) */ 69static FILE usual[FOPEN_MAX - 3]; 70static struct glue uglue = { 0, FOPEN_MAX - 3, usual }; 71 72FILE __sF[3] = { 73 std(__SRD, STDIN_FILENO), /* stdin */ 74 std(__SWR, STDOUT_FILENO), /* stdout */ 75 std(__SWR|__SNBF, STDERR_FILENO) /* stderr */ 76}; 77 78struct glue __sglue = { &uglue, 3, __sF }; 79 80static struct glue * 81moreglue(n) 82 register int n; 83{ 84 register struct glue *g; 85 register FILE *p; 86 static FILE empty; 87 88 g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE)); 89 if (g == NULL) 90 return (NULL); 91 p = (FILE *)ALIGN(g + 1); 92 g->next = NULL; 93 g->niobs = n; 94 g->iobs = p; 95 while (--n >= 0) 96 *p++ = empty; 97 return (g); 98} 99 100/* 101 * Find a free FILE for fopen et al. 102 */ 103FILE * 104__sfp() 105{ 106 register FILE *fp; 107 register int n; 108 register struct glue *g; 109 110 if (!__sdidinit) 111 __sinit(); 112 for (g = &__sglue;; g = g->next) { 113 for (fp = g->iobs, n = g->niobs; --n >= 0; fp++) 114 if (fp->_flags == 0) 115 goto found; 116 if (g->next == NULL && (g->next = moreglue(NDYNAMIC)) == NULL) 117 break; 118 } 119 return (NULL); 120found: 121 fp->_flags = 1; /* reserve this slot; caller sets real flags */ 122 fp->_p = NULL; /* no current pointer */ 123 fp->_w = 0; /* nothing to read or write */ 124 fp->_r = 0; 125 fp->_bf._base = NULL; /* no buffer */ 126 fp->_bf._size = 0; 127 fp->_lbfsize = 0; /* not line buffered */ 128 fp->_file = -1; /* no file */ 129/* fp->_cookie = <any>; */ /* caller sets cookie, _read/_write etc */ 130 fp->_ub._base = NULL; /* no ungetc buffer */ 131 fp->_ub._size = 0; 132 fp->_lb._base = NULL; /* no line buffer */ 133 fp->_lb._size = 0; 134 return (fp); 135} 136 137/* 138 * XXX. Force immediate allocation of internal memory. Not used by stdio, 139 * but documented historically for certain applications. Bad applications. 140 */ 141void 142f_prealloc() 143{ 144 register struct glue *g; 145 int n; 146 147 n = getdtablesize() - FOPEN_MAX + 20; /* 20 for slop. */ 148 for (g = &__sglue; (n -= g->niobs) > 0 && g->next; g = g->next) 149 /* void */; 150 if (n > 0) 151 g->next = moreglue(n); 152} 153 154/* 155 * exit() calls _cleanup() through *__cleanup, set whenever we 156 * open or buffer a file. This chicanery is done so that programs 157 * that do not use stdio need not link it all in. 158 * 159 * The name `_cleanup' is, alas, fairly well known outside stdio. 160 */ 161void 162_cleanup() 163{ 164 /* (void) _fwalk(fclose); */ 165 (void) _fwalk(__sflush); /* `cheating' */ 166} 167 168/* 169 * __sinit() is called whenever stdio's internal variables must be set up. 170 */ 171void 172__sinit() 173{ 174 /* make sure we clean up on exit */ 175 _IO_cleanup = _cleanup; /* conservative */ 176 __sdidinit = 1; 177} 178