Dynamic char Array - C / C++ / MFC Discussion Boards

led mike2-Jul-09 9:00

2-Jul-09 9:00

I've never used that API but based on the documentation my first guess would be that if entriesRead is more than 1 the buffer will contain an array of them so you would iterate through the array, something like:

PLOCALGROUP_MEMBERS_INFO_1 pData = (PLOCALGROUP_MEMBERS_INFO_1)buffer;

for(int i = 0;i< entriesRead ;i++, pData++)
{
  pData->lgrmi1_sid;  // etc.
}

Of course I would have to verify that by debugging since I've never worked with it.

BTW: Don't forget to free the buffer Wink | ;)

"bufptr [out]

Pointer to the address that receives the return information structure. The format of this data depends on the value of the level parameter. This buffer is allocated by the system and must be freed using the NetApiBufferFree function. Note that you must free the buffer even if the function fails with ERROR_MORE_DATA."

Re: convert vbscript to c++

Mogaambo2-Jul-09 9:06

Mogaambo

2-Jul-09 9:06

Here what i get after a lot of googling or say binging

LPLOCALGROUP_MEMBERS_INFO_1 pstMembersInfo = 0;
DWORD entriesread = 0;
DWORD totalentries = 0;
if( 0 != NetLocalGroupGetMembers( NULL, _T("Administrators"), 1, (LPBYTE*)
&pstMembersInfo,MAX_PREFERRED_LENGTH,
&entriesread, &totalentries, 0 ))
{
AfxMessageBox( _T("NetLocalGroupGetMembers failed !"));
return ;
}
for( DWORD dwIdx =0; dwIdx < entriesread; dwIdx ++ )
{
AfxMessageBox( pstMembersInfo[dwIdx].lgrmi1_name );
}
NetApiBufferFree( pstMembersInfo );

“You will never be a leader unless you first learn to follow and be led.”
–Tiorio

"Coming together is a beginning, staying together is progress, and working together is success." Henry Ford

Re: convert vbscript to c++

Stuart Dootson2-Jul-09 9:26

Stuart Dootson

2-Jul-09 9:26

That's pretty much equivalent to Mike's - it's just the casting's done slightly differently.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: convert vbscript to c++

Mogaambo2-Jul-09 9:28

Mogaambo

2-Jul-09 9:28

cout<< pData->lgrmi1_name <<std::endl; //how can i get name here as it is printing only address like below

printf("%S\n", pData->lgrmi1_name );;

“You will never be a leader unless you first learn to follow and be led.”
–Tiorio

"Coming together is a beginning, staying together is progress, and working together is success." Henry Ford

Re: convert vbscript to c++

David Crow2-Jul-09 9:31

David Crow

2-Jul-09 9:31

Mogaambo wrote:
cout<< pData->lgrmi1_name <<std::endl; how="" can="" i="" get="" name="" here="" as="" it="" is="" printing="" only="" address="" like="" below<="" blockquote="">

Have you tried wcout?

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Re: convert vbscript to c++

Mogaambo2-Jul-09 9:39

Mogaambo

2-Jul-09 9:39

Thanks to all for helping me a lot, actually i am c# programmer and i dont know all these jargons.

Thks alot

“You will never be a leader unless you first learn to follow and be led.”
–Tiorio

"Coming together is a beginning, staying together is progress, and working together is success." Henry Ford

Re: convert vbscript to c++

Mogaambo2-Jul-09 9:41

Mogaambo

2-Jul-09 9:41

// adminGroup.cpp : Defines the entry point for the console application.
//
#pragma comment(lib,"Netapi32.lib")
#include <stdio.h>
#include <windows.h>

#include < LMCONS.H>
#include <Lm.h>
#include <Lmaccess.h>
#define MAX_PREFERRED_LENGTH ((DWORD) -1)
#include "stdafx.h"

#include <iostream>

#include <string>
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{

// NET_API_STATUS ret = 0 ;
//LPCWSTR servername = NULL;
//LPCWSTR groupname = L"Administrators";
LPBYTE buffer = NULL;
//DWORD entriesRead;
//DWORD totalEntries;
//DWORD resumeHandle =0;
//
//typedef struct _LOCALGROUP_MEMBERS_INFO_1 {
// PSID lgrmi1_sid;
// SID_NAME_USE lgrmi1_sidusage;
// LPWSTR lgrmi1_name;
//}LOCALGROUP_MEMBERS_INFO_1, *PLOCALGROUP_MEMBERS_INFO_1, *LPLOCALGROUP_MEMBERS_INFO_1;
////function call
//ret=NetLocalGroupGetMembers (NULL, groupname, 1, &buffer, MAX_PREFERRED_LENGTH, &entriesRead, &totalEntries, &resumeHandle);
//LPLOCALGROUP_MEMBERS_INFO_1 pstMembersInfo = 0;
//for( DWORD dwIdx =0; dwIdx < entriesRead; dwIdx ++ )
//{
// //std::cout<< pstMembersInfo[dwIdx].lgrmi1_name ;
//}
//int n=0;

LPLOCALGROUP_MEMBERS_INFO_1 pstMembersInfo = 0;
DWORD entriesread = 0;
DWORD totalentries = 0;
LPWSTR FromFile2=NULL;
if( 0 != NetLocalGroupGetMembers( NULL, _T("Administrators"), 1, (LPBYTE*)
&buffer,MAX_PREFERRED_LENGTH,
&entriesread, &totalentries, 0 ))
{
//AfxMessageBox( _T("NetLocalGroupGetMembers failed !"));
// return ;
}
PLOCALGROUP_MEMBERS_INFO_1 pData = (PLOCALGROUP_MEMBERS_INFO_1)buffer;
for( DWORD dwIdx =0; dwIdx < entriesread; dwIdx ++ , pData++)
{
//printf("%S\n", pstMembersInfo[dwIdx].lgrmi1_name );;

//lstrcpy(FromFile2,pstMembersInfo[dwIdx].lgrmi1_name);
//std::cout<<(std::string) pstMembersInfo[dwIdx].lgrmi1_name <<std::endl;
wcout<< pData->lgrmi1_name <<std::endl;
//printf("%S\n", pData->lgrmi1_name );;
}
NetApiBufferFree( buffer );

return 0;

}

“You will never be a leader unless you first learn to follow and be led.”
–Tiorio

"Coming together is a beginning, staying together is progress, and working together is success." Henry Ford

Dynamic char Array

jlgeris2-Jul-09 5:38

jlgeris

2-Jul-09 5:38

Essentially, I'm reading some names from a text file, and I need to allocate the array at runtime. I'm missing something regarding the allocation of each individual name. After I copy the first name into the array slot, it fills up every spot in the array with the first value. After the loop finishes I have an array with [count] copies of the initial value I read from the file.

I'm using the StreamReader class in other places in the program so that's why I'm marshaling the string to a char*. Maybe not the ideal solution, but I believe the problem is separate from that.

char **temp=NULL;
my_malloc((void**)&temp,count*sizeof(char*));

StreamReader^ din = File::OpenText(fileName);
String^ str;

while ((str = din->ReadLine()) != nullptr)
{			
  char* x = (char*)System::Runtime::InteropServices::Marshal::StringToHGlobalAnsi(str).ToPointer();
  my_malloc((void**)&temp[count],strlen(x)*sizeof(char)+1);  //i imagine the problem is here
  strcpy(temp[count],x);				     //or here
  System::Runtime::InteropServices::Marshal::FreeHGlobal((IntPtr)x);
  count++;
}

The my_malloc function is just a wrapper around free() and malloc().

Thanks for the help.

Re: Dynamic char Array

jlgeris2-Jul-09 5:42

jlgeris

2-Jul-09 5:42

FYI

int my_malloc(void **param_adr, int param_size)
{
    my_free(param_adr);
    if ((*param_adr = malloc(param_size)) == NULL)
    {
        return -1;
    }
    memset(*param_adr,0,param_size);

    return 0;
}

void my_free(void **param_adr)
{
    if (*param_adr != NULL)
    {
        free(*param_adr);
        *param_adr = NULL;
    }
    return;
}

Re: Dynamic char Array

«_Superman_»2-Jul-09 5:54

«_Superman_»

2-Jul-09 5:54

You're mixing managed and unmanaged code in a very strange way.

«_Superman_»
I love work. It gives me something to do between weekends.

Re: Dynamic char Array

jlgeris2-Jul-09 7:14

jlgeris

2-Jul-09 7:14

I know. This was the quick and dirty solution, but i'm open to alternatives.

Re: Dynamic char Array

Stuart Dootson2-Jul-09 9:20

Stuart Dootson

2-Jul-09 9:20

How about using an

<a href="http://msdn.microsoft.com/en-us/library/ts4c4dw6(VS.80).aspx">array</a><<a href="http://msdn.microsoft.com/en-us/library/system.string(VS.80).aspx">String</a>^>^

(i.e. a C++/CLI array of C++/CLI strings) instead of standard C types?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: Dynamic char Array

jlgeris2-Jul-09 9:32

jlgeris

2-Jul-09 9:32

Well, I need the array in that format because I'm working with another proprietary API that works only with standard C types.

Re: Dynamic char Array

Stuart Dootson2-Jul-09 10:46

Stuart Dootson

2-Jul-09 10:46

jlgeris wrote:
temp[count]

When you allocated temp, you allocated temp[0] to temp[count-1] - temp[count] is undefined. Either use a different index variable or reset count to 0

jlgeris wrote:
strlen(x)*sizeof(char)+1

As sizeof(char)==1, it makes no difference, but you really wanted (strlen(x)+1)*sizeof(char)

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

CString::Format causing Advanced Direct Buffer Access error

colm omahony2-Jul-09 5:18

colm omahony

2-Jul-09 5:18

Hello,
my program takes in a large file(s) of byte code and writes it into thousands of smaller files.
The program gives an MFC42D.DLL: 0xC00000005 Access Violation when it reaches the first of two lines of code below.

<pre> siteAndChannelIDStr.Format("C:\\Network Data\\Unclassified Events\\Last Extracted\\%s\\#%d\\", siteNamesArray[listBoxIndex], OCUIDfromEALFile);
CreateDirectory(siteAndChannelIDStr, NULL);

The CString object and directory are successfully created during the previous iterations, but oddly fails this time round.

I have followed the program execution using the debugger and it falls down at "if" statement in the "Advanced direct buffer access" bit in MFC\SRC\STRCORE.cpp

<code> if (GetData()->nRefs > 1 || nMinBufLength > GetData()->nAllocLength)

I have tried setting siteAndChannelIDStr = ""; after use
And changing the Format function to one described on the microsoft website <a href="http://support.microsoft.com/kb/127038"></a>
And tried using CString Arrays for the siteNamesArray

But no luck!
Has anyone come across this type of problem before?

I have tried the program out on 3 different files, but it fails at the same line (although prog had passed this line for each previous hundreds of iterations)

It fails after subfile 4977/10893 in file1
after subfile 4901/8135 in file2
after subfile 384/13321 in file3

Any help would be greatly appreciated!
I can provide more information if necessary. I cannot put up source code as it is for my work.

Thanks,
Colm

Re: CString::Format causing Advanced Direct Buffer Access error

Stuart Dootson2-Jul-09 6:33

Stuart Dootson

2-Jul-09 6:33

The error implies GetData() is returning zero - why is that happening?

Are you running out of memory possibly?

What are the parameter values going into the function?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: CString::Format causing Advanced Direct Buffer Access error

colm omahony3-Jul-09 3:29

colm omahony

3-Jul-09 3:29

Just checked in the debugger and nMinBufLength is 91 for the other calls to GetBuffer() is only 55 on the call that causes the error.
So I think running out of memeory is the problem somehow...
I've tried siteAndChannelIDStr.ReleaseBuffer(); and siteAndChannelIDStr = "";

I tried shortening the lenght of the filePath and it is still failing at the same location.

What params do you require -
I cannot get anymore values - for previous iterations nRefs=-1, nDataLength=0, nAllocLength=0

Thanks again,
Colm

Re: CString::Format causing Advanced Direct Buffer Access error

Stuart Dootson3-Jul-09 3:37

Stuart Dootson

3-Jul-09 3:37

colm omahony wrote:
Just checked in the debugger and nMinBufLength is 91 for the other calls to GetBuffer() is only 55 on the call that causes the error.
So I think running out of memeory is the problem somehow...

In that case, you need to be releasing memory somewhere - but what is it that's taking up all the memory?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: CString::Format causing Advanced Direct Buffer Access error

colm omahony12-Jul-09 23:15

colm omahony

12-Jul-09 23:15

Hi, I was on holidays for last while. Thanks for assistance. Will look into what is taking the memory.

Re: CString::Format causing Advanced Direct Buffer Access error

colm omahony12-Jul-09 23:55

colm omahony

12-Jul-09 23:55

Hello Stuart, is this a memory leak or is it likely to be something different. I am not getting a memory leak error message.

Re: CString::Format causing Advanced Direct Buffer Access error

Stuart Dootson12-Jul-09 23:59

Stuart Dootson

12-Jul-09 23:59

Either that or you're using an invalid string object in there somehow.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

transparent window with OpenGL

kedanz2-Jul-09 5:08

kedanz

2-Jul-09 5:08

Hi,

OpenGL default background is black. I want the background is total transparent in Windows. Anyone has an example how to do it?

Re: transparent window with OpenGL

led mike2-Jul-09 5:35

led mike

2-Jul-09 5:35

Never used it. A quick investigation using Google tells me that basically it is not directly supported. Some people have stated that this solution[^] works. Good luck.

Re: transparent window with OpenGL

Sarath C2-Jul-09 5:39

Sarath C

2-Jul-09 5:39

I never programmed an OpenGL with transperancy in background. Are you looking for something like this?

ftp://download.nvidia.com/XFree86/Linux-x86/169.12/README/chapter-23.html[^]

-Sarath.
"Great hopes make everything great possible" - Benjamin Franklin

My blog - Sharing My Thoughts

Re: transparent window with OpenGL

Karl Phillip2-Jun-11 6:10

Karl Phillip

2-Jun-11 6:10

This thread shows how: http://stackoverflow.com/q/4052940/176769

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.