[omniORB] Memory problem with string_out argument

Thu, 16 Nov 2000 10:20:46 -0500

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Hello... List !

I have a little problem with an out argument of type "string" and the
destruction...
A BIG ASSERT!!!

the IDL Interface goes like this :
interface server
{
	long get_string(out string message);
};

The problem raise from the use of "_var" type. The client call the
get_string as it follow :
{
server_ptr MyServer =3D ...; // Valid ref
CORBA::Long Result;
CORBA::String_var buffer;
...

Result =3D get_string(buffer);	// Everything goes fine and I have the
message.
cout << Buffer; 			// Everything goes fine and I see
the message.
...				// No used of buffer at all.
return Result;
}				// Crash with the String_var::~String_var()

And the line that could help me is this one. Does anybody got a hint =
for
that problem

       /*
         * If this ASSERT fails, a bad pointer has been passed in. It =
may be
         * totally bogus, or it may have been allocated from another =
heap.
         * The pointer MUST come from the 'local' heap.
         */
        _ASSERTE(_CrtIsValidHeapPointer(pUserData));   // pUserData =
realy
point to my returned string...!!! and CRASH.

Does the _out agument created by the proxy are allocated on my 'local' =
heap
?

Just to be sure, I can create and destroy string_var like this without =
any
problem :
{
	CORBA::String_var buffer =3D (const char *)"Olivier";
}

Thanks for help

      Olivier Thibout=F4t
      VOXCO Inc.
      o.thiboutot@voxco.com
      tel  : (514) 861-9255
      fax : (514) 861-9209

P.S. : this code work fine but the _var solution should work too, no ?
{
	CORBA::Long Result;
	char * Buffer;
			/*	CORBA::String_var Buffer;   */

	Result =3D get_string(Buffer);
	cout << Buffer;
	CORBA::string_free(Buffer); 	// Everything goes fine !!!!
}

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<P><FONT SIZE=3D2 FACE=3D"Arial">Hello... List !</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">I have a little problem with an out =
argument of type &quot;string&quot; and the destruction...</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">A BIG ASSERT!!!</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">the IDL Interface goes like this =
:</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">interface server</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">{</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">long get_string(out string message);</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">};</FONT>
</P>

The problem raise from the use of =
&quot;_var&quot; type. The client call the get_string as it follow =
:
 {
 server_ptr MyServer =3D ...; // Valid =
ref
 CORBA::Long Result;
 CORBA::String_var buffer;
 ...

<P><FONT SIZE=3D2 FACE=3D"Arial">Result =3D =
get_string(buffer);&nbsp;&nbsp;&nbsp; // Everything goes fine and I =
have the message.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">cout &lt;&lt; Buffer; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Everything goes fine and =
I see the message.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">...&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // No used of buffer at =
all.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">return Result;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">}&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Crash with the =
String_var::~String_var()</FONT>
</P>

And the line that could help me is =
this one. Does anybody got a hint for that problem

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
/*
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; * If =
this ASSERT fails, a bad pointer has been passed in. It may be
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; * =
totally bogus, or it may have been allocated from another heap.
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; * =
The pointer MUST come from the 'local' heap.
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
*/
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
_ASSERTE(_CrtIsValidHeapPointer(pUserData));&nbsp;&nbsp; // pUserData =
realy point to my returned string...!!! and CRASH.

<P><FONT SIZE=3D2 FACE=3D"Arial">Does the _out agument created by the =
proxy are allocated on my 'local' heap ?</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Just to be sure, I can create and =
destroy string_var like this without any problem :</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">{</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">CORBA::String_var buffer =3D (const char =
*)&quot;Olivier&quot;;</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">}</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Thanks for help</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Olivier =
Thibout=F4t</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; VOXCO =
Inc.</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
o.thiboutot@voxco.com</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
tel&nbsp; : (514) 861-9255</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; fax : =
(514) 861-9209</FONT>
</P>
<BR>

P.S. : this code work fine but the =
_var solution should work too, no ?
 {
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CORBA::Long Result;
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; char * Buffer;
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /*&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CORBA::String_var =
Buffer;&nbsp;&nbsp; */

<P>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">Result =3D get_string(Buffer);</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">cout &lt;&lt; Buffer;</FONT>
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <FONT SIZE=3D2 =
FACE=3D"Arial">CORBA::string_free(Buffer); &nbsp;&nbsp;&nbsp; // =
Everything goes fine !!!!</FONT>
<BR><FONT SIZE=3D2 FACE=3D"Arial">}</FONT>
</P>

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