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
|
/*
* read() - POSIX 1003.1b 6.4.1 - Read From a File
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
* Copyright assigned to U.S. Government, 1994.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#include "libio_.h"
/* XXX newlib has the prototype for this wrong. It will be a bit painful */
/* XXX to fix so we are choosing to delay fixing this. */
int read(
int fd,
void *buffer,
unsigned32 count
)
{
int rc; /* XXX change to a size_t when prototype is fixed */
rtems_libio_t *iop;
rtems_libio_check_fd( fd );
iop = rtems_libio_iop( fd );
rtems_libio_check_buffer( buffer );
rtems_libio_check_count( count );
rtems_libio_check_permissions( iop, LIBIO_FLAGS_READ );
/*
* If this file descriptor is mapped to an external set of handlers,
* then pass the request on to them.
*/
if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
rtems_libio_read_t fp;
fp = rtems_libio_handlers[
(iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].read;
if ( fp == NULL )
set_errno_and_return_minus_one( EBADF );
return (*fp)( fd, buffer, count );
}
/*
* Now process the read().
*/
if ( !iop->handlers->read )
set_errno_and_return_minus_one( ENOTSUP );
rc = (*iop->handlers->read)( iop, buffer, count );
if ( rc > 0 )
iop->offset += rc;
return rc;
}
/*
* _read_r
*
* This is the Newlib dependent reentrant version of read().
*/
#if defined(RTEMS_NEWLIB)
#include <reent.h>
_ssize_t _read_r(
struct _reent *ptr,
int fd,
void *buf,
size_t nbytes
)
{
return read( fd, buf, nbytes );
}
#endif
|
