Jakub Hrozek modified ares_parse_srv_reply() and ares_parse_txt_reply() API

to return a linked lists of results. These were also modified to internally
use the ares_data memory struct and as such its result must be free'ed with
ares_free_data().
This commit is contained in:
Yang Tse 2009-11-20 09:06:33 +00:00
parent 5a0a473c30
commit 7e6a67b436
4 changed files with 78 additions and 76 deletions

View File

@ -476,13 +476,11 @@ CARES_EXTERN int ares_parse_ns_reply(const unsigned char *abuf,
CARES_EXTERN int ares_parse_srv_reply(const unsigned char* abuf,
int alen,
struct ares_srv_reply** srv_out,
int *nsrvreply);
struct ares_srv_reply** srv_out);
CARES_EXTERN int ares_parse_txt_reply(const unsigned char* abuf,
int alen,
struct ares_txt_reply** txt_out,
int *nsrvreply);
struct ares_txt_reply** txt_out);
CARES_EXTERN void ares_free_string(void *str);

View File

@ -34,7 +34,8 @@
** of c-ares functions returning pointers that must be free'ed using this
** function is:
**
** FIXME: specify function list.
** ares_parse_srv_reply()
** ares_parse_txt_reply()
*/
void ares_free_data(void *dataptr)

View File

@ -1,6 +1,7 @@
/* Id$ */
/* $Id$ */
/* Copyright 1998 by the Massachusetts Institute of Technology.
* Copyright (C) 2009 by Jakub Hrozek <jhrozek@redhat.com>
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
@ -15,11 +16,6 @@
* without express or implied warranty.
*/
/*
* ares_parse_srv_reply created by Jakub Hrozek <jhrozek@redhat.com>
* on behalf of Red Hat - http://www.redhat.com
*/
#include "ares_setup.h"
#ifdef HAVE_SYS_SOCKET_H
@ -47,6 +43,7 @@
#include <string.h>
#include "ares.h"
#include "ares_dns.h"
#include "ares_data.h"
#include "ares_private.h"
/* AIX portability check */
@ -56,21 +53,20 @@
int
ares_parse_srv_reply (const unsigned char *abuf, int alen,
struct ares_srv_reply **srv_out, int *nsrvreply)
struct ares_srv_reply **srv_out)
{
unsigned int qdcount, ancount;
unsigned int qdcount, ancount, i;
const unsigned char *aptr;
int status, i, rr_type, rr_class, rr_len;
int status, rr_type, rr_class, rr_len;
long len;
char *hostname = NULL, *rr_name = NULL;
struct ares_srv_reply *srv = NULL;
struct ares_srv_reply *srv_head = NULL;
struct ares_srv_reply *srv_last = NULL;
struct ares_srv_reply *srv_curr;
/* Set *srv_out to NULL for all failure cases. */
*srv_out = NULL;
/* Same with *nsrvreply. */
*nsrvreply = 0;
/* Give up if abuf doesn't have room for a header. */
if (alen < HFIXEDSZ)
return ARES_EBADRESP;
@ -96,14 +92,6 @@ ares_parse_srv_reply (const unsigned char *abuf, int alen,
}
aptr += len + QFIXEDSZ;
/* Allocate ares_srv_reply array; ancount gives an upper bound */
srv = malloc ((ancount) * sizeof (struct ares_srv_reply));
if (!srv)
{
free (hostname);
return ARES_ENOMEM;
}
/* Examine each answer resource record (RR) in turn. */
for (i = 0; i < (int) ancount; i++)
{
@ -134,40 +122,58 @@ ares_parse_srv_reply (const unsigned char *abuf, int alen,
break;
}
srv[i].priority = ntohs (*((unsigned short *)aptr));
/* Allocate storage for this SRV answer appending it to the list */
srv_curr = ares_malloc_data(ARES_DATATYPE_SRV_REPLY);
if (!srv_curr)
{
status = ARES_ENOMEM;
break;
}
if (srv_last)
{
srv_last->next = srv_curr;
}
else
{
srv_head = srv_curr;
}
srv_last = srv_curr;
srv_curr->priority = ntohs (*((unsigned short *)aptr));
aptr += sizeof(unsigned short);
srv[i].weight = ntohs (*((unsigned short *)aptr));
srv_curr->weight = ntohs (*((unsigned short *)aptr));
aptr += sizeof(unsigned short);
srv[i].port = ntohs (*((unsigned short *)aptr));
srv_curr->port = ntohs (*((unsigned short *)aptr));
aptr += sizeof(unsigned short);
status = ares_expand_name (aptr, abuf, alen, &srv[i].host, &len);
status = ares_expand_name (aptr, abuf, alen, &srv_curr->host, &len);
if (status != ARES_SUCCESS)
break;
/* Move on to the next record */
aptr += len;
/* Don't lose memory in the next iteration */
free (rr_name);
rr_name = NULL;
}
/* Don't lose memory in the next iteration */
free (rr_name);
rr_name = NULL;
}
if (hostname)
free (hostname);
if (rr_name)
free (rr_name);
/* clean up on error */
if (status != ARES_SUCCESS)
{
free (srv);
free (hostname);
free (rr_name);
if (srv_head)
ares_free_data (srv_head);
return status;
}
/* everything looks fine, return the data */
*srv_out = srv;
*nsrvreply = ancount;
*srv_out = srv_head;
free (hostname);
free (rr_name);
return status;
return ARES_SUCCESS;
}

View File

@ -1,8 +1,7 @@
/* $Id$ */
/* Copyright 1998 by the Massachusetts Institute of Technology.
* Copyright (C) 2009 Jakub Hrozek <jhrozek@redhat.com>
* Copyright (C) 2009 Yang Tse <yangsita@gmail.com>
* Copyright (C) 2009 by Jakub Hrozek <jhrozek@redhat.com>
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
@ -49,11 +48,12 @@
#include "ares.h"
#include "ares_dns.h"
#include "ares_data.h"
#include "ares_private.h"
int
ares_parse_txt_reply (const unsigned char *abuf, int alen,
struct ares_txt_reply **txt_out, int *ntxtreply)
struct ares_txt_reply **txt_out)
{
size_t substr_len, str_len;
unsigned int qdcount, ancount, i;
@ -62,14 +62,13 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
int status, rr_type, rr_class, rr_len;
long len;
char *hostname = NULL, *rr_name = NULL;
struct ares_txt_reply *txt = NULL;
struct ares_txt_reply *txt_head = NULL;
struct ares_txt_reply *txt_last = NULL;
struct ares_txt_reply *txt_curr;
/* Set *txt_out to NULL for all failure cases. */
*txt_out = NULL;
/* Same with *ntxtreply. */
*ntxtreply = 0;
/* Give up if abuf doesn't have room for a header. */
if (alen < HFIXEDSZ)
return ARES_EBADRESP;
@ -95,21 +94,6 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
}
aptr += len + QFIXEDSZ;
/* Allocate ares_txt_reply array; ancount gives an upper bound */
txt = malloc ((ancount) * sizeof (struct ares_txt_reply));
if (!txt)
{
free (hostname);
return ARES_ENOMEM;
}
/* Initialize ares_txt_reply array */
for (i = 0; i < ancount; i++)
{
txt[i].txt = NULL;
txt[i].length = 0;
}
/* Examine each answer resource record (RR) in turn. */
for (i = 0; i < ancount; i++)
{
@ -133,6 +117,23 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
/* Check if we are really looking at a TXT record */
if (rr_class == C_IN && rr_type == T_TXT)
{
/* Allocate storage for this SRV answer appending it to the list */
txt_curr = ares_malloc_data(ARES_DATATYPE_TXT_REPLY);
if (!txt_curr)
{
status = ARES_ENOMEM;
break;
}
if (txt_last)
{
txt_last->next = txt_curr;
}
else
{
txt_head = txt_curr;
}
txt_last = txt_curr;
/*
* There may be multiple substrings in a single TXT record. Each
* substring may be up to 255 characters in length, with a
@ -146,13 +147,13 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
while (strptr < (aptr + rr_len))
{
substr_len = (unsigned char)*strptr;
txt[i].length += substr_len;
txt_curr->length += substr_len;
strptr += substr_len + 1;
}
/* Including null byte */
txt[i].txt = malloc (txt[i].length + 1);
if (txt[i].txt == NULL)
txt_curr->txt = malloc (txt_curr->length + 1);
if (txt_curr->txt == NULL)
{
status = ARES_ENOMEM;
break;
@ -165,12 +166,12 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
{
substr_len = (unsigned char)*strptr;
strptr++;
memcpy ((char *) txt[i].txt + str_len, strptr, substr_len);
memcpy ((char *) txt_curr->txt + str_len, strptr, substr_len);
str_len += substr_len;
strptr += substr_len;
}
/* Make sure we NULL-terminate */
txt[i].txt[txt[i].length] = '\0';
*((char *) txt_curr->txt + txt_curr->length) = '\0';
/* Move on to the next record */
aptr += rr_len;
@ -189,17 +190,13 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen,
/* clean up on error */
if (status != ARES_SUCCESS)
{
for (i = 0; i < ancount; i++)
{
if (txt[i].txt)
free (txt[i].txt);
}
if (txt_head)
ares_free_data (txt_head);
return status;
}
/* everything looks fine, return the data */
*txt_out = txt;
*ntxtreply = ancount;
*txt_out = txt_head;
return ARES_SUCCESS;
}