73ef4ff3
 Hu Chunming
提交三方库
|
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
|
.\"
.\" Copyright 1998 by the Massachusetts Institute of Technology.
.\"
.\" Permission to use, copy, modify, and distribute this
.\" software and its documentation for any purpose and without
.\" fee is hereby granted, provided that the above copyright
.\" notice appear in all copies and that both that copyright
.\" notice and this permission notice appear in supporting
.\" documentation, and that the name of M.I.T. not be used in
.\" advertising or publicity pertaining to distribution of the
.\" software without specific, written prior permission.
.\" M.I.T. makes no representations about the suitability of
.\" this software for any purpose. It is provided "as is"
.\" without express or implied warranty.
.\"
.TH ARES_PARSE_TXT_REPLY 3 "27 October 2009"
.SH NAME
ares_parse_txt_reply \- Parse a reply to a DNS query of type TXT
.SH SYNOPSIS
.nf
.B #include <ares.h>
.PP
.B int ares_parse_txt_reply(const unsigned char* \fIabuf\fP, int \fIalen\fP,
.B struct ares_txt_reply **\fItxt_out\fP);
.PP
.B int ares_parse_txt_reply_ext(const unsigned char* \fIabuf\fP, int \fIalen\fP,
.B struct ares_txt_ext **\fItxt_out\fP);
.fi
.SH DESCRIPTION
The
.BR "ares_parse_txt_reply" " (" "ares_parse_txt_reply_ext" ")"
function parses the response to a query of type TXT into a
linked list (one element per sub-string) of
.IR "struct ares_txt_reply" " (" "struct ares_txt_ext" ")"
The parameters
.I abuf
and
.I alen
give the contents of the response. The result is stored in allocated
memory and a pointer to it stored into the variable pointed to by
.IR txt_out .
It is the caller's responsibility to free the resulting
.IR txt_out
structure when it is no longer needed using the function
.B ares_free_data
.PP
The structure
.I ares_txt_reply
contains the following fields:
.sp
.in +4n
.nf
struct ares_txt_reply {
struct ares_txt_reply *next;
unsigned int length;
unsigned char *txt;
};
.fi
.in
.PP
The structure
.I ares_txt_ext
contains the following fields:
.sp
.in +4n
.nf
struct ares_txt_ext {
struct ares_txt_ext *next;
unsigned int length;
unsigned char *txt;
unsigned char record_start;
};
.fi
.in
.PP
The
.I record_start
field in
.I struct ares_txt_ext
is 1 if this structure is a start of a TXT record, and 0 if the structure is a
continuation of a previous record. The linked list of the
.I struct ares_txt_ext
will have at least one item with
.I record_start
equal to 1, and may have some items with
.I record_start
equal to 0 between them.
.PP
These sequences of
.I struct ares_txt_ext
(starting from the item with
.I record_start
equal to 1, and ending right before the record start item) may be treated as
either components of a single TXT record or as a multi-parted TXT record,
depending on particular use case.
.PP
.SH RETURN VALUES
.BR "ares_parse_txt_reply" " (" "ares_parse_txt_reply_ext" ")"
can return any of the following values:
.TP 15
.B ARES_SUCCESS
The response was successfully parsed.
.TP 15
.B ARES_EBADRESP
The response was malformatted.
.TP 15
.B ARES_ENODATA
The response did not contain an answer to the query.
.TP 15
.B ARES_ENOMEM
Memory was exhausted.
.SH AVAILABILITY
This function was first introduced in c-ares version 1.7.0.
.SH SEE ALSO
.BR ares_query (3)
.BR ares_free_data (3)
.SH AUTHOR
Written by Jakub Hrozek <jhrozek@redhat.com>, on behalf of Red Hat, Inc http://www.redhat.com
.PP
Amended by Fedor Indutny <fedor@indutny.com>, on behalf of PayPal, Inc https://www.paypal.com
|
