1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
/* Copyright (C) 1994, 1995, 1996 Free Software Foundation, Inc.
Ported to standalone by Joel Sherrill jsherril@redstone-emh2.army.mil,
On-Line Applications Research Corporation.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <errno.h>
#include <unistd.h>
#include <stddef.h>
#include "filedesc.h"
#include <fcntl.h>
#include <standalone.h>
/* Read NBYTES into BUF from FD. Return the number read or -1. */
ssize_t
__libc_read (int fd, void *buf, size_t nbytes)
{
char *buffer = (char *) buf;
int data;
int poll;
__set_errno (0);
if (nbytes == 0)
return 0;
if ( !__FD_Is_valid( fd ) || !__FD_Table[ fd ].in_use )
{
__set_errno (EBADF);
return -1;
}
if (buf == NULL)
{
__set_errno (EINVAL);
return -1;
}
if ( __FD_Table[ fd ].flags & O_WRONLY ) /* is it write only? */
{
__set_errno (EBADF);
return -1;
}
/* If this is a non-blocking fd, then we want to poll the console. */
poll = ( __FD_Table[ fd ].flags & O_NONBLOCK ) ? 1 : 0;
/* Read a single character. This is a cheap way to insure that the
upper layers get every character because _Console_Getc can't timeout
or otherwise know when to stop. */
data = _Console_Getc(poll);
if ( data == -1 ) /* if no data return */
return -1;
(void) _Console_Putc(data); /* echo the character */
if ( data == '\r' ) { /* translate CR -> CR/LF */
(void) _Console_Putc('\n');
data = '\n';
}
*buffer = data;
return 1;
}
weak_alias (__libc_read, __read)
weak_alias (__libc_read, read)
|
