FreeTDS Development Group

[Brian Bruns <camber AT ais.org>]

James,

Instead of dumping to stderr which might not be desirable in some 
applications (PHP for instance) is it possible to use tds_client_msg() to 
alert the upper layer app of the problem?

I've just checked in all my changes for the connectionless client message 
handling stuff-thing-whatchamacallit.  So we should be all set here 
whether we have a socket allocated at this time or not.

Bill, we should be able to fix all the convert errors now, sorry it took 
so long.

Brian

On 9 Aug 2002, James Cameron wrote:

> I'm yet to understand exactly how Casey's environment led to a failure
> to report hostname resolution followed by a bogus IP address being used
> ... I've asked them for more detail.
> 
> On Fri, 2002-08-09 at 09:09, Brian Bruns wrote:
> > I'm going to take part of the blame for this as well.  Our reporting of 
> > hostname resolution problems needs to be much better.  I'm not sure when 
> > I 
> > can get to rolling up a patch, anyone else up for it?
> 
> I've changed the code to report the failure of gethostbyname() to stderr
> and the TDSDUMP log.  Here are the changes I'm proposing.  I haven't
> committed them yet.  Could I have a review please?
> 
> diff -u -r1.108 ChangeLog
> --- ChangeLog   8 Aug 2002 04:33:55 -0000       1.108
> +++ ChangeLog   9 Aug 2002 01:57:16 -0000
> @@ -1,3 +1,12 @@
> +Fri Aug  9 11:56:01 2002  James Cameron  <quozl AT us.netrek.org>
> +
> +       * src/tds/config.c (lookup_host): report failure of
> gethostbyname
> +       to stderr and TDSDUMP log, and return a null string as result.
> +
> +       * src/tds/threadsafe.c (tds_gethostbyname_r): adjust the
> +       non-reentrant version of the code to return h_errno now that it
> is
> +       required by lookup_host().
> +
>  Thu Aug  8 00:13:30 EDT 2002   JK Lowden <jklowden AT schemamania.org>
>         + include/tds.h.in      tdsmoney now a union of TDS_INT8 and
> TDS_OLD_MONEY
>         + src/tds/convert.c     reinstituted numeric-based money
> handling.  
> 
> 
> 
> diff -u -r1.18 config.c
> --- src/tds/config.c    7 Jul 2002 04:33:15 -0000       1.18
> +++ src/tds/config.c    9 Aug 2002 01:57:30 -0000
> @@ -569,8 +569,32 @@
>        This call take a while and is useless for an ip address.
>        mlilback 3/2/02 */
>     ip_addr = inet_addr(servername);
> -   if (ip_addr == INADDR_NONE)
> +   if (ip_addr == INADDR_NONE) {
>        host = tds_gethostbyname_r(servername, &result, buffer, buflen,
> &h_errnop);
> +      /* check result of gethostbyname and propogate any failure */
> +      if (host == NULL) {
> +         char *reason = "unknown";
> +         switch (h_errnop) {
> +         case HOST_NOT_FOUND:
> +            reason = "specified name is unknown";
> +            break;
> +         case NO_ADDRESS:
> +         case NO_DATA:
> +            reason = "name is valid but has no IP address";
> +            break;
> +         case NO_RECOVERY:
> +            reason = "non-recoverable name server error occurred";
> +            break;
> +         case TRY_AGAIN:
> +            reason = "temporary error on authoritative name server";
> +            break;
> +         }
> +        fprintf(stderr, "src/tds/config.c: lookup_host: gethostbyname:
> %s, %s\n", servername, rea
> son);
> +         tdsdump_log(TDS_DBG_ERROR, "%L gethostbyname(%s) failed with
> \"%s\".\n",servername,reaso
> n);
> +         ip[0] = '\0';
> +         return;
> +      }
> +   }
>  
>  #ifndef NOREVERSELOOKUPS
>  /* froy AT singleentry.com 12/21/2000 */
> 
> 
> 
> 
> diff -u -r1.5 threadsafe.c
> --- src/tds/threadsafe.c        9 Jul 2002 01:55:05 -0000       1.5
> +++ src/tds/threadsafe.c        9 Aug 2002 01:57:45 -0000
> @@ -78,8 +78,10 @@
>  tds_gethostbyname_r(const char *servername, struct hostent *result,
> char *buffer, int buflen, int
>  *h_errnop)
>  {
>  #ifndef _REENTRANT
> -       return gethostbyname(servername);
> -
> +       extern int h_errno;
> +       struct hostent *result = gethostbyname(servername);
> +       h_errnop = &h_errno;
> +       return result;
>  #else
>  
>  #if defined(HAVE_FUNC_GETHOSTBYNAME_R_6)
> 
> 
>