C / C++ / MFC

Re: How to check null or corrupted char pointer value

8-Jan-09 1:34

Are you calling it this way (assuming 'translate' as the name of the function pointer)?

char * psz1 = "Hello";
char * psz2;
HRESULT hr = translate( psz1, psz2);

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

KASR18-Jan-09 1:41

KASR1

8-Jan-09 1:41

yes. small change as below

char * psz1 = "Hello";
char * psz2 = NULL;
HRESULT hr = translate( psz1, psz2);

Re: How to check null or corrupted char pointer value

CPallini8-Jan-09 1:50

Re: How to check null or corrupted char pointer value

8-Jan-09 1:50

Well, psz2 initialization shouldn't matter.
Have you any documentation of the library?
(Maybe the function has some weird pre-requisite, like psz2 pointing to a client-allocated buffer...I know it doesn't make sense, but several real pieces of code actually does not make sense).

Smile | :)

KASR18-Jan-09 1:57

KASR1

8-Jan-09 1:57

Thanks for replying soon.

The below logic given by Randor seems working.

MEMORY_BASIC_INFORMATION mbi;
VirtualQueryEx(GetCurrentProcess(),pVar,&mbi,sizeof(mbi));
if (mbi.Protect == PAGE_NOACCESS)
{
   // bad pointer
}

Re: How to check null or corrupted char pointer value

CPallini8-Jan-09 2:06

Re: How to check null or corrupted char pointer value

8-Jan-09 2:06

I'm glad about, but doesn't the HRESULT return value give some info about the translate operation?

Randor 8-Jan-09 2:19

Randor

8-Jan-09 2:19

Well, technically it could be other values. For example you may recieve a ramdom garbage pointer which resolves to a loaded PE image. A better implementation for checking a variable pointer would be:

MEMORY_BASIC_INFORMATION mbi;
VirtualQueryEx(GetCurrentProcess(),pVar,&mbi,sizeof(mbi));
if (mbi.Protect == PAGE_READWRITE && mbi.State = MEM_COMMIT && mbi.Type == MEM_PRIVATE)
{
	// bad string pointer
}

This ensures:

1.) You can read and write to the address.
2.) The address is allocated and committed memory.
3.) The address is within the private region.

At this point the chance of being a good pointer has become substantially higher.

Best Wishes,
-David Delaune

INetFwMgr

barneyb817-Jan-09 23:11

barneyb81

7-Jan-09 23:11

I'm trying to obtain the Windows Firewall status, which is simple enough using the get_FirewallEnabled method on INetFwProfile. The problem is that this only retrieves the local policy, which could have been overridden by the group policy and so is sometimes wrong.

Does anyone know if there's a way of retrieving the group policy? There's a get_CurrentProfileType on INetFwMgr, but this just seems to return NET_FW_PROFILE_STANDARD regardless of the policy. There's a NEW_FW_POLICY_TYPE enum, but it's not used in any methods that I can find.

Thanks!

Re: INetFwMgr

Hamid_RT7-Jan-09 23:48

7-Jan-09 23:48

MSDN has examples for work with Firewall did you see
Using Windows Firewall API[^]?

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

Re: INetFwMgr

barneyb817-Jan-09 23:55

barneyb81

7-Jan-09 23:55

Thanks. I'd read through this documentation, and can't find any way of obtaining the group policy (or indeed even of telling whether or not the local policy is being overridden). Given the existence of the NET_FW_POLICY_TYPE enum, I'd like to think it's possible, but I'm starting to think maybe it's not...

protocol using vc++

hrishiS7-Jan-09 22:09

hrishiS

7-Jan-09 22:09

hello Experts,
I would like to know the basics of how to use SIP protocol using vc++.This is not regards to any project. Just for my self learning.

Thanks,
Himangshu

CPallini7-Jan-09 22:39

7-Jan-09 22:39

Do you know the wonderful CodeProject article search engine [^]?
Smile | :)

hrishiS7-Jan-09 23:17

hrishiS

7-Jan-09 23:17

thx, I will go through it

Hamid_RT7-Jan-09 23:31

7-Jan-09 23:31

Does it[^] helpful?

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

toxcct8-Jan-09 1:30

8-Jan-09 1:30

Hamid. wrote:
Does it[^] helpful?

Should be "Is it Helpful"...

anyway, happy new year Hamid, and congratulations for your new status Wink | ;)

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You....

CPallini8-Jan-09 1:43

8-Jan-09 1:43

You grammar-nazi... Mad | :mad:

Happy new year tox! Big Grin | :-D

Re: You....

toxcct8-Jan-09 1:54

8-Jan-09 1:54

CPallini wrote:
You grammar-nazi

no insults please Poke tongue | ;-P

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Hamid_RT8-Jan-09 1:46

8-Jan-09 1:46

Thanks where are you old friend? and congratulations for your mvp again. Big Grin | :-D

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

toxcct8-Jan-09 1:52

8-Jan-09 1:52

Hamid. wrote:
where are you

under my own work... no time anymore to roam on CP baords that much Wink | ;)

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CPallini8-Jan-09 1:57

8-Jan-09 1:57

Hamid. wrote:
Thanks where are you old friend?

Tox deserted: you may find him togheter with the enemy, in the java forum... Roll eyes | :rolleyes:

Hamid_RT8-Jan-09 2:01

8-Jan-09 2:01

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

toxcct8-Jan-09 2:50

8-Jan-09 2:50

CPallini wrote:
Tox deserted

I didn't

I just don't have much time, and quite tired answering to google it or to look into an FAQ.

CPallini wrote:
with the enemy, in the java forum

Java is not enemy Mad | :mad:

not much than C# at least, so you'd better revise your judgement and spit at VB scripters instead.

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CPallini8-Jan-09 3:14

8-Jan-09 3:14

toxcct wrote:
Java is not enemy not much than C# at least

Java *is* the (MS) enemy, C# was invented to fight Java. (fighting VB scripters is like bombing the Red Cross).

BTW: Did you notice the joke icon?
Big Grin | :-D

toxcct8-Jan-09 3:25