1/* Copyright (C) 1993, 1997 Free Software Foundation, Inc. 2 This file is part of the GNU IO Library. 3 4 This library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU General Public License as 6 published by the Free Software Foundation; either version 2, or (at 7 your option) any later version. 8 9 This library is distributed in the hope that it will be useful, but 10 WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this library; see the file COPYING. If not, write to 16 the Free Software Foundation, 59 Temple Place - Suite 330, Boston, 17 MA 02111-1307, USA. 18 19 As a special exception, if you link this library with files 20 compiled with a GNU compiler to produce an executable, this does 21 not cause the resulting executable to be covered by the GNU General 22 Public License. This exception does not however invalidate any 23 other reasons why the executable file might be covered by the GNU 24 General Public License. */ 25 26/* 27 * Copyright (c) 1990 The Regents of the University of California. 28 * All rights reserved. 29 * 30 * Redistribution and use in source and binary forms are permitted 31 * provided that the above copyright notice and this paragraph are 32 * duplicated in all such forms and that any documentation, 33 * advertising materials, and other materials related to such 34 * distribution and use acknowledge that the software was developed 35 * by the University of California, Berkeley. The name of the 36 * University may not be used to endorse or promote products derived 37 * from this software without specific prior written permission. 38 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 39 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 40 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 41 */ 42 43/* Modified for GNU iostream by Per Bothner 1991, 1992. */ 44 45#include "libioP.h" 46#include <sys/types.h> 47#include <sys/stat.h> 48#ifdef __STDC__ 49#include <stdlib.h> 50#include <unistd.h> 51#endif 52 53#ifdef _LIBC 54# undef isatty 55# define isatty(Fd) __isatty (Fd) 56#endif 57 58/* 59 * Allocate a file buffer, or switch to unbuffered I/O. 60 * Per the ANSI C standard, ALL tty devices default to line buffered. 61 * 62 * As a side effect, we set __SOPT or __SNPT (en/dis-able fseek 63 * optimisation) right after the _fstat() that finds the buffer size. 64 */ 65 66int 67_IO_file_doallocate (fp) 68 _IO_FILE *fp; 69{ 70 _IO_size_t size; 71 int couldbetty; 72 char *p; 73 struct stat st; 74 75#if !defined(_LIBC) && !defined(__linux__) 76 /* If _IO_cleanup_registration_needed is non-zero, we should call the 77 function it points to. This is to make sure _IO_cleanup gets called 78 on exit. We call it from _IO_file_doallocate, since that is likely 79 to get called by any program that does buffered I/O. */ 80 if (_IO_cleanup_registration_needed) 81 (*_IO_cleanup_registration_needed) (); 82#endif 83 84 if (fp->_fileno < 0 || _IO_SYSSTAT (fp, &st) < 0) 85 { 86 couldbetty = 0; 87 size = _IO_BUFSIZ; 88#if 0 89 /* do not try to optimise fseek() */ 90 fp->_flags |= __SNPT; 91#endif 92 } 93 else 94 { 95 couldbetty = S_ISCHR (st.st_mode); 96#if _IO_HAVE_ST_BLKSIZE 97 size = st.st_blksize <= 0 ? _IO_BUFSIZ : st.st_blksize; 98#else 99 size = _IO_BUFSIZ; 100#endif 101 } 102 ALLOC_BUF (p, size, EOF); 103 _IO_setb (fp, p, p + size, 1); 104 if (couldbetty && isatty (fp->_fileno)) 105 fp->_flags |= _IO_LINE_BUF; 106 return 1; 107} 108