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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
/**
* @file
* SNMP pbuf stream wrapper implementation (internal API, do not use in client code).
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Martin Hentschel <[email protected]>
*
*/
#include "lwip/apps/snmp_opts.h"
#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
#include "snmp_pbuf_stream.h"
#include "lwip/def.h"
#include <string.h>
err_t
snmp_pbuf_stream_init(struct snmp_pbuf_stream *pbuf_stream, struct pbuf *p, u16_t offset, u16_t length)
{
pbuf_stream->offset = offset;
pbuf_stream->length = length;
pbuf_stream->pbuf = p;
return ERR_OK;
}
err_t
snmp_pbuf_stream_read(struct snmp_pbuf_stream *pbuf_stream, u8_t *data)
{
if (pbuf_stream->length == 0) {
return ERR_BUF;
}
if (pbuf_copy_partial(pbuf_stream->pbuf, data, 1, pbuf_stream->offset) == 0) {
return ERR_BUF;
}
pbuf_stream->offset++;
pbuf_stream->length--;
return ERR_OK;
}
err_t
snmp_pbuf_stream_write(struct snmp_pbuf_stream *pbuf_stream, u8_t data)
{
return snmp_pbuf_stream_writebuf(pbuf_stream, &data, 1);
}
err_t
snmp_pbuf_stream_writebuf(struct snmp_pbuf_stream *pbuf_stream, const void *buf, u16_t buf_len)
{
if (pbuf_stream->length < buf_len) {
return ERR_BUF;
}
if (pbuf_take_at(pbuf_stream->pbuf, buf, buf_len, pbuf_stream->offset) != ERR_OK) {
return ERR_BUF;
}
pbuf_stream->offset += buf_len;
pbuf_stream->length -= buf_len;
return ERR_OK;
}
err_t
snmp_pbuf_stream_writeto(struct snmp_pbuf_stream *pbuf_stream, struct snmp_pbuf_stream *target_pbuf_stream, u16_t len)
{
if ((pbuf_stream == NULL) || (target_pbuf_stream == NULL)) {
return ERR_ARG;
}
if ((len > pbuf_stream->length) || (len > target_pbuf_stream->length)) {
return ERR_ARG;
}
if (len == 0) {
len = LWIP_MIN(pbuf_stream->length, target_pbuf_stream->length);
}
while (len > 0) {
u16_t chunk_len;
err_t err;
u16_t target_offset;
struct pbuf *pbuf = pbuf_skip(pbuf_stream->pbuf, pbuf_stream->offset, &target_offset);
if ((pbuf == NULL) || (pbuf->len == 0)) {
return ERR_BUF;
}
chunk_len = LWIP_MIN(len, pbuf->len);
err = snmp_pbuf_stream_writebuf(target_pbuf_stream, &((u8_t *)pbuf->payload)[target_offset], chunk_len);
if (err != ERR_OK) {
return err;
}
pbuf_stream->offset += chunk_len;
pbuf_stream->length -= chunk_len;
len -= chunk_len;
}
return ERR_OK;
}
err_t
snmp_pbuf_stream_seek(struct snmp_pbuf_stream *pbuf_stream, s32_t offset)
{
if (((pbuf_stream->offset + offset) < 0) || (offset > pbuf_stream->length)) {
/* we cannot seek backwards or forward behind stream end */
return ERR_ARG;
}
pbuf_stream->offset += (u16_t)offset;
pbuf_stream->length -= (u16_t)offset;
return ERR_OK;
}
err_t
snmp_pbuf_stream_seek_abs(struct snmp_pbuf_stream *pbuf_stream, u32_t offset)
{
s32_t rel_offset = offset - pbuf_stream->offset;
return snmp_pbuf_stream_seek(pbuf_stream, rel_offset);
}
#endif /* LWIP_SNMP */
|
