Copyright 1998 by the Massachusetts Institute of Technology.
SPDX-License-Identifier: MIT
ARES_PARSE_TXT_REPLY 3 "27 October 2009"
NAME
ares_parse_txt_reply - Parse a reply to a DNS query of type TXT
SYNOPSIS
#include <ares.h> int ares_parse_txt_reply(const unsigned char* abuf, int alen, struct ares_txt_reply **txt_out); int ares_parse_txt_reply_ext(const unsigned char* abuf, int alen, struct ares_txt_ext **txt_out);
DESCRIPTION
The ares_parse_txt_reply(3) and ares_parse_txt_reply_ext(3)
functions parse the response to a query of type TXT into a linked list (one
element per sub-string) of
"struct ares_txt_reply" " (" "struct ares_txt_ext" ")" The parameters
abuf and
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
txt_out . It is the caller's responsibility to free the resulting
txt_out structure when it is no longer needed using the function
ares_free_data(3).
The structure
ares_txt_reply contains the following fields:
struct ares_txt_reply { struct ares_txt_reply *next; unsigned int length; unsigned char *txt; };The structure ares_txt_ext contains the following fields:
struct ares_txt_ext { struct ares_txt_ext *next; unsigned int length; unsigned char *txt; unsigned char record_start; };The record_start field in 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 struct ares_txt_ext will have at least one item with record_start equal to 1, and may have some items with record_start equal to 0 between them. These sequences of struct ares_txt_ext (starting from the item with 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.
RETURN VALUES
"ares_parse_txt_reply" " (" "ares_parse_txt_reply_ext" ")" can return any of the following values:
15 ARES_SUCCESS The response was successfully parsed.
15 ARES_EBADRESP The response was malformatted.
15 ARES_ENODATA The response did not contain an answer to the query.
15 ARES_ENOMEM Memory was exhausted.
AVAILABILITY
This function was first introduced in c-ares version 1.7.0.
SEE ALSO
ares_query (3) ares_free_data (3) AUTHOR
Written by Jakub Hrozek <jhrozek@redhat.com>, on behalf of Red Hat, Inc http://www.redhat.com
Amended by Fedor Indutny <fedor@indutny.com>, on behalf of PayPal, Inc https://www.paypal.com