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
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/****************************************************************************
* net/iob/iob_copyout.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_DEBUG) && defined(CONFIG_IOB_DEBUG)
/* Force debug output (from this file only) */
# undef CONFIG_DEBUG_NET
# define CONFIG_DEBUG_NET 1
#endif
#include <stdint.h>
#include <string.h>
#include <assert.h>
#include <nuttx/net/iob.h>
#include "iob.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef MIN
# define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: iob_copyout
*
* Description:
* Copy data 'len' bytes of data into the user buffer starting at 'offset'
* in the I/O buffer, returning that actual number of bytes copied out.
*
****************************************************************************/
int iob_copyout(FAR uint8_t *dest, FAR const struct iob_s *iob,
unsigned int len, unsigned int offset)
{
FAR const uint8_t *src;
unsigned int ncopy;
unsigned int avail;
unsigned int remaining;
/* Skip to the I/O buffer containing the offset */
while (offset >= iob->io_len)
{
offset -= iob->io_len;
iob = iob->io_flink;
}
/* Then loop until all of the I/O data is copied to the user buffer */
remaining = len;
while (iob && remaining > 0)
{
/* Get the source I/O buffer offset address and the amount of data
* available from that address.
*/
src = &iob->io_data[iob->io_offset + offset];
avail = iob->io_len - offset;
/* Copy the from the I/O buffer in to the user buffer */
ncopy = MIN(avail, remaining);
memcpy(dest, src, ncopy);
/* Adjust the total length of the copy and the destination address in
* the user buffer.
*/
remaining -= ncopy;
dest += ncopy;
/* Skip to the next I/O buffer in the chain */
iob = iob->io_flink;
offset = 0;
}
return len - remaining;
}
|
