Re: the memory leak - C / C++ / MFC Discussion Boards

XML Docs supported for C++ in 2003 or 2005?

Todd Smith2-Nov-05 11:53

2-Nov-05 11:53

I know XML Docs are supported for C# is VS.NET but what about C++? If XML Docs aren't supported natively for C++, has anyone come out with an add-on that implements them?

Todd Smith

Load testing & performance monitoring

Todd Smith2-Nov-05 11:33

Todd Smith

2-Nov-05 11:33

Let say I've written a MMO server. Then I write a small C++ class called Bot that emulates a typical client session. Next I write a small test harness which can launch instances of Bots in separate threads.

The questions is how can I determine the max viable number of bot threads for a given machine? Every machine will have a different CPU/RAM configuartion etc. Can I determine at run-time how many bot threads to launch? I've tested my app with 500 bots and it works fine. I crank it up to 1000 bots and my system comes to a crawl.

Todd Smith

the memory leak

valerie992-Nov-05 11:22

valerie99

2-Nov-05 11:22

good afternoon, could anyone see where is the leak from? thank you! I've checked the momory allocation, the leak is happening around here:

strcpy( FileName, BinPath );
strcat( FileName, "CALLSM" );
strcat( FileName, Cycle);
strcat( FileName, ".BIN" );
if ( _access ( FileName, 0 ) != 0 )
{
sprintf( ErrorText, "File does not exist -> %s", FileName );
Message( ErrorText, VD_ERROR );
return 0;
}
m_information_line = "Loading CALLSUM Binary File.";
PostUpdate();
CallSumBin = new CALLSUM_BIN( FileName );
if ( !CallSumBin )
{
Message( "Unable to allocate CallSumBin binfile.", VD_ERROR );
return 0;
}

here is the delete in closedown() function:
if ( CallSumBin )
{
if ( !IsStop() ) {
strcpy( FileName, BinPath );
strcat( FileName, "CALLSM" );
strcat( FileName, Cycle);
strcat( FileName, ".BIN" );
m_information_line = "Saving updated CALLSM binary file";
PostUpdate();
CallSumBin->Save( FileName );
fprintf( Report,"Updated CALLSM binary file saved.\r\n" );
}
delete CallSumBin;
}
m_information_line = " ";
PostUpdate();

-- modified at 17:23 Wednesday 2nd November, 2005

Re: the memory leak

Christian Graus2-Nov-05 11:53

Christian Graus

2-Nov-05 11:53

valerie99 wrote:
strcpy( FileName, BinPath );

Where is Filename allocated ? Is it ever deleted ?

C style string handling is a messy pile of crap, and the perfect way to get memory leaks. Why are you not using C++ here ?

Christian Graus - Microsoft MVP - C++

Re: the memory leak

kakan2-Nov-05 18:44

kakan

2-Nov-05 18:44

As far as I can see, the memory leak must be in the CALLSUM_BIN class.

Re: the memory leak

toxcct2-Nov-05 21:17

toxcct

2-Nov-05 21:17

i don't see any here...

you CallSumBin = new CALLSUM_BIN( FileName ); and always delete CallSumBin; it then...

so, you might have a look at the CALLSUM_BIN constructor... does it allocate some memory that is not deleted (at the end of the constructor or in the destructor ?

TOXCCT >>> GEII power
[toxcct][VisualCalc]

-- modified at 3:18 Thursday 3rd November, 2005

Re: the memory leak

krmed3-Nov-05 2:54

krmed

3-Nov-05 2:54

Is your code perhaps calling the function containing
CallSumBin = new CALLSUM_BIN( FileName );
more than once without having called the closedown() function?

If so, that will cause a memory leak. I would suggest the following:

if ( _access ( FileName, 0 ) != 0 )<br />
{<br />
sprintf( ErrorText, "File does not exist -> %s", FileName );<br />
Message( ErrorText, VD_ERROR );<br />
return 0;<br />
}<br />
m_information_line = "Loading CALLSUM Binary File.";<br />
PostUpdate();<br />
if (CallSumBin != NULL)<br />
{<br />
    delete CallSumBin;<br />
    CallSumBin = NULL;<br />
}<br />
CallSumBin = new CALLSUM_BIN( FileName );<br />
if ( !CallSumBin )<br />
{<br />
Message( "Unable to allocate CallSumBin binfile.", VD_ERROR );<br />
return 0;<br />
}

Karl - WK5M
PP-ASEL-IA (N43CS)
<kmedcalf@ev1.net>
PGP Key: 0xDB02E193
PGP Key Fingerprint: 8F06 5A2E 2735 892B 821C 871A 0411 94EA DB02 E193

Re: the memory leak

Tim Smith3-Nov-05 3:55

Tim Smith

3-Nov-05 3:55

As krmed already stated, make sure your allocation routine isn't being called multiple times. However, I wouldn't make krmed's change, since that might just be fixing the symptoms and not the real issue. It is the memory allocation version of the "off by one" error where someone fixes the problem by just adding one without tracking down the reason why the value is off by one.

Another problem might be that your closedown code isn't being invoked. I often see people spend endless amounts of time trying to figure out why are routine isn't working when in fact, the routine isn't even being invoked.

Both of those problems are the same class of problem, improper execution path.

Of course, this is all assuming that it is CallSumBin that is leaking. If you haven't verified that, then you might be looking at the wrong issue.

As to what Christian said, he is right. Constructing the filename like that is akin to running with scissors. As long as you are careful, things are "ok". But a slight mistake can cause memory corruption (which can manifest itself as a leak in some instances) and security issues. I won't go so far as saying C style is crap, mainly because I have seen far too many string processing systems created with managed strings that are just dogs. But you are playing with fire and really need to understand what you are doing when you do work with C strings.

Tim Smith

I'm going to patent thought. I have yet to see any prior art.

-- modified at 9:56 Thursday 3rd November, 2005

AscW

samkook2-Nov-05 10:18

samkook

2-Nov-05 10:18

is there an equivalent function in c++ of the vb function AscW?

because I need to convert a unicode character into it's hexadecimal value.

Re: AscW

toxcct2-Nov-05 21:14

toxcct

2-Nov-05 21:14

hexadecimal is just a printing representation of an integer value...
just use the %x or %X format option in the format string of the printf(), sprintf(), .Format() functions...

TOXCCT >>> GEII power
[toxcct][VisualCalc]

Re: AscW

samkook3-Nov-05 8:28

samkook

3-Nov-05 8:28

I can convert an integer into hexadecimal, but i can't convert a wchar_t into an integer.

I tried: swprintf(iTest,"%d",wByteBuff);
but i always get the error :error C2665: 'swprintf' : none of the 2 overloads can convert parameter 1 from type 'int'

i also tried with %x,%X,%i,%u,%c but none of this is working.

xml in tree view control

gr8coaster3292-Nov-05 10:05

gr8coaster329

2-Nov-05 10:05

i am trying to load the data from an xml document into a treeview control. i know how to write the xml document but do not know how to load all of the data into tree control.

any help would be greatly appreciated.

- Kyle

Re: xml in tree view control

AskQuestion2-Nov-05 10:28

AskQuestion

2-Nov-05 10:28

look this site

http://www.codeproject.com/atl/atl_persistxml.asp[^]

Re: xml in tree view control

gr8coaster3292-Nov-05 12:41

gr8coaster329

2-Nov-05 12:41

AskQuestion wrote:
look this site

http://www.codeproject.com/atl/atl_persistxml.asp[^]

that is not vc++ is it??

- Kyle

Re: xml in tree view control

AskQuestion3-Nov-05 0:20

AskQuestion

3-Nov-05 0:20

Look, there is a *.dsw file in the demo download file. In Description the author (katasonov)wrote:

"I have created two Visual Studio 6.0 projects as an example of how easy it is to add XML support to ATL objects:........"

have a look, I hope I could help you

Anyone know a good tutorial on VC++ 6?

Lord Kixdemp2-Nov-05 8:20

Lord Kixdemp

2-Nov-05 8:20

Hello everyone! Big Grin | :-D

OK, I got VC++ 6 yesterday, and I'm trying to make a Windows app, but I got no idea how! I looked for tutorials but they're all either for command-line apps (which I already read one) or for VC++ 2003... I've coded in C++ before, but not for Windows... I need a basic introduction to how to create a GUI/form/window from scratch. Anyone know? Thanks! Wink | ;-)

Sulfurik K. Nosferathus (Darth_Sulfur)
www.SulfurMidis.com
www.SulfurSoft.tk
http://www.BeepXtreme.tk
[ftp://][http://][hotline://]tsfc.ath.cx

Re: Anyone know a good tutorial on VC++ 6?

Ravi Bhavnani2-Nov-05 8:38

Ravi Bhavnani

2-Nov-05 8:38

See this[^] link.

/ravi

My new year's resolution: 2048 x 1536
Home | Music | Articles | Freeware | Trips
ravib(at)ravib(dot)com

Re: Anyone know a good tutorial on VC++ 6?

Lord Kixdemp2-Nov-05 9:06

Lord Kixdemp

2-Nov-05 9:06

Yeah, that's one of the sites that are for VC++ 2003... Frown | :(

But I already figured out how to do it... Now I need to know how to retrieve the text from a text label on my dialog. Do you know how? Thanks! Wink | ;-)

Sulfurik K. Nosferathus (Darth_Sulfur)
www.SulfurMidis.com
www.SulfurSoft.tk
http://www.BeepXtreme.tk
[ftp://][http://][hotline://]tsfc.ath.cx

Re: Anyone know a good tutorial on VC++ 6?

Kevin McFarlane2-Nov-05 9:24

Kevin McFarlane

2-Nov-05 9:24

Darth_Sulfur wrote:
Yeah, that's one of the sites that are for VC++ 2003...

I had a quick glance at this the other day and in certain places they give instructions for both VC++ 6 and VC++ 2003.

Darth_Sulfur wrote:
Now I need to know how to retrieve the text from a text label on my dialog.

Haven't done any VC++/MFC for quite some time but, from memory, you may need something like GetWindowText() or GetDlgItemText().

Kevin

Re: Anyone know a good tutorial on VC++ 6?

Ravi Bhavnani2-Nov-05 9:46

Ravi Bhavnani

2-Nov-05 9:46

Also see this[^] article.

To get/set a control's text, use GetWindowText() or SetWindowText().

A good book on MFC and the basics of Windows programming is Programming Windows with MFC by Jeff Prosise[^]. You can find cheap on EBay here[^].

/ravi

My new year's resolution: 2048 x 1536
Home | Music | Articles | Freeware | Trips
ravib(at)ravib(dot)com

Re: Anyone know a good tutorial on VC++ 6?

Steve Mayfield2-Nov-05 10:23

Steve Mayfield

2-Nov-05 10:23

totally agree...the Prosise book is a great MFC book. I also have the Petzold book right next to it (programming Windows 5th Ed)

Steve

Re: Anyone know a good tutorial on VC++ 6?

Lord Kixdemp2-Nov-05 13:56

Lord Kixdemp

2-Nov-05 13:56

Yeah, that GetDlgItemText() worked! Thanks! Big Grin | :-D

And I'll buy that book if I find it on a store, you need to be very wise and powerful and have tons of patience to convince my dad to buy something off eBay... Thanks! Big Grin | :-D

Now, I got into new trouble... I accidentally put in a breakpoint in some file which of I can't remember its name... How do I remove all of the breakpoints? I can't run my program anymore! Frown | :-(

Thanks!

Sulfurik K. Nosferathus (Darth_Sulfur)
www.SulfurMidis.com
www.SulfurSoft.tk
http://www.BeepXtreme.tk
[ftp://][http://][hotline://]tsfc.ath.cx

Re: Anyone know a good tutorial on VC++ 6?

Ravi Bhavnani3-Nov-05 2:16

Ravi Bhavnani

3-Nov-05 2:16

Darth_Sulfur wrote:
How do I remove all of the breakpoints?

Re: Anyone know a good tutorial on VC++ 6?

toxcct3-Nov-05 3:35

toxcct

3-Nov-05 3:35

Darth_Sulfur wrote:
How do I remove all of the breakpoints?

Ravi Bhavnani wrote:
Edit | Breakpoints | Remove All

Ctrl + Shift + F9 Smile | :)

TOXCCT >>> GEII power
[toxcct][VisualCalc]

-- modified at 9:41 Thursday 3rd November, 2005

Re: Anyone know a good tutorial on VC++ 6?

Ravi Bhavnani3-Nov-05 4:32

Ravi Bhavnani

3-Nov-05 4:32

Even better!

/ravi

My new year's resolution: 2048 x 1536
Home | Music | Articles | Freeware | Trips
ravib(at)ravib(dot)com

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