.
[glibc/history.git] / libio / filedoalloc.c
blobca02dbeb3405dd16d5608e7509161e56c36f3eef
1 /* Copyright (C) 1993, 1997, 2001, 2002 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA.
19 As a special exception, if you link the code in this file with
20 files compiled with a GNU compiler to produce an executable,
21 that does not cause the resulting executable to be covered by
22 the GNU Lesser General Public License. This exception does not
23 however invalidate any other reasons why the executable file
24 might be covered by the GNU Lesser General Public License.
25 This exception applies to code released by its copyright holders
26 in files containing the exception. */
29 Copyright (C) 1990 The Regents of the University of California.
30 All rights reserved.
32 Redistribution and use in source and binary forms, with or without
33 modification, are permitted provided that the following conditions
34 are met:
36 1. Redistributions of source code must retain the above copyright
37 notice, this list of conditions and the following disclaimer.
38 2. Redistributions in binary form must reproduce the above copyright
39 notice, this list of conditions and the following disclaimer in the
40 documentation and/or other materials provided with the distribution.
41 4. Neither the name of the University nor the names of its contributors
42 may be used to endorse or promote products derived from this software
43 without specific prior written permission.
45 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
46 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48 ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
49 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55 SUCH DAMAGE.*/
57 /* Modified for GNU iostream by Per Bothner 1991, 1992. */
59 #ifndef _POSIX_SOURCE
60 # define _POSIX_SOURCE
61 #endif
62 #include "libioP.h"
63 #include <sys/types.h>
64 #include <sys/stat.h>
65 #ifdef __STDC__
66 #include <stdlib.h>
67 #include <unistd.h>
68 #endif
70 #ifdef _LIBC
71 # undef isatty
72 # define isatty(Fd) __isatty (Fd)
74 # include <device-nrs.h>
75 #endif
78 * Allocate a file buffer, or switch to unbuffered I/O.
79 * Per the ANSI C standard, ALL tty devices default to line buffered.
81 * As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
82 * optimisation) right after the _fstat() that finds the buffer size.
85 int
86 _IO_file_doallocate (fp)
87 _IO_FILE *fp;
89 _IO_size_t size;
90 char *p;
91 struct _G_stat64 st;
93 #ifndef _LIBC
94 /* If _IO_cleanup_registration_needed is non-zero, we should call the
95 function it points to. This is to make sure _IO_cleanup gets called
96 on exit. We call it from _IO_file_doallocate, since that is likely
97 to get called by any program that does buffered I/O. */
98 if (__builtin_expect (_IO_cleanup_registration_needed != NULL, 0))
99 (*_IO_cleanup_registration_needed) ();
100 #endif
102 size = _IO_BUFSIZ;
103 if (fp->_fileno >= 0 && __builtin_expect (_IO_SYSSTAT (fp, &st), 0) >= 0)
105 if (S_ISCHR (st.st_mode))
107 /* Possibly a tty. */
108 if (
109 #ifdef DEV_TTY_P
110 DEV_TTY_P (&st) ||
111 #endif
112 isatty (fp->_fileno))
113 fp->_flags |= _IO_LINE_BUF;
115 #if _IO_HAVE_ST_BLKSIZE
116 if (st.st_blksize > 0)
117 size = st.st_blksize;
118 #endif
120 ALLOC_BUF (p, size, EOF);
121 INTUSE(_IO_setb) (fp, p, p + size, 1);
122 return 1;
124 INTDEF(_IO_file_doallocate)