Commit 7e6a67b4 authored by Yang Tse's avatar Yang Tse
Browse files

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().
parent 5a0a473c

ares/ares.h

+2 −4
Original line number Diff line number Diff line
@@ -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);

ares/ares_data.c

+2 −1
Original line number Diff line number Diff line
@@ -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)

ares/ares_parse_srv_reply.c

+43 −37
Original line number Diff line number Diff line 
/* 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;

    }

    }



  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;

}

ares/ares_parse_txt_reply.c

+31 −34
Original line number Diff line number Diff line 
/* $Id$ */



/* 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;

}