C / C++ / MFC

Re: DFT or FFT Library for C++ and FFTW Problems

18-Jun-09 1:35

jobin007007 wrote:
I tried using FFTW from fftw.org

Why don't you try to compile the library on your system?

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]

jobin00700718-Jun-09 4:38

jobin007007

18-Jun-09 4:38

Thats what I did!!.

If you have any fftw that compiles fine in 64 bit computer in Visual Studio 2008 EITHER STATIC OR dynamic, could you send it to me?

Vc++ dll creation

anishkannan17-Jun-09 19:09

17-Jun-09 19:09

Hai:
Any body help me

i m working in c# application. i need algorithm to our application. but i have that algorithm in c++. so i converted c++ to Vc++ application using Vc++ console wizard Express Edition 2008 .after that created a dll then used in c# application . but put Entry point Exception occurred. i thing, i was used wrong wizard. which wizard want to used. and what are step are followed to this scenario..

Please Help me soon....

CPallini17-Jun-09 21:26

17-Jun-09 21:26

anishkannan wrote:
but i have that algorithm in c++. so i converted c++ to Vc++ application using Vc++ console wizard Express Edition 2008 .

You may also convert it (crafting by hand) in C#, I suppose.

anishkannan wrote:
but put Entry point Exception occurred.

What was exactly the error? When it occurred? You should be detailed and precise when reporting error (you should also possibly report both the DLL and the calling relevant code).

anishkannan wrote:
what are step are followed to this scenario..

One simple path is what you've actually done: build a DLL (compliant with system ones) and then use Platform Invoke, see, for instance [^].

anishkannan wrote:
Please Help me soon....

Do you know, you loosed man points for this?
Smile | :)

anishkannan17-Jun-09 22:56

17-Jun-09 22:56

Thank you for the replay

I was created a dll using Console application of Vc++ Express Edition. After that i used the dll in sample C# application (Used in same system and also same platform)

My code is
[DllImport("Hash.dll",EntryPoint = "getHashCode" ) ]
static extern int getHashCode();
static void Main(string[] args)
{
try
{
Console.WriteLine(getHashCode());

Console.ReadKey();

}
catch (Exception e)
{
Console.WriteLine(e.Message);

}

I got this Exception

Unable to find an entry point named 'getHashCode' in DLL 'Hash.dll'.

Thankyou

CPallini17-Jun-09 23:05

17-Jun-09 23:05

Can you see the exported getHashCode with, for instance, Depends tool?

What I mean: Is the function correctly exported? Could you show, please, the relevant DLL code?

Smile | :)

anishkannan17-Jun-09 23:34

17-Jun-09 23:34

yes, same function name used here.

This is the Vc++ code.

#include "stdafx.h"
#include "HashTable.h"

int main(array<System::String ^> ^args)
{
Console::WriteLine(L"Hello World");

return 0;
}
static int getHashCode()
{
const char* name="bhjbhj";

HashTable g;

return g.hashPJW(name);

}

Thank you

CPallini17-Jun-09 23:41

17-Jun-09 23:41

That doesn't look like an ordinary DLL exporting functions like system libraries do.
AFAIK DLL should have a DLLMain entry point (instead of main) and so on.
Why are you building a DLL with managed C++? Cannot you simply code it using C#?
Smile | :)

anishkannan17-Jun-09 23:51

17-Jun-09 23:51

so what i do, create proper one. want to used any specific wizard.

Thankyou...

CPallini18-Jun-09 0:00

18-Jun-09 0:00

Why don't you answer to my questions? Why do you need a C++ DLL if the Framework is involved? Cannot you simply write a C# function?
Smile | :)

anishkannan18-Jun-09 0:08

18-Jun-09 0:08

ya possible to write C# code. but why i am trying like this, in our application need some more algorithm to further development that also have c++ code. which is not possible to write c# code . thats may take more time. But c++ code is working properly also tested. so only we are going c++ code.

Thankyou

CPallini18-Jun-09 0:38

How to Connect C++ code with MySQL

18-Jun-09 0:38

In order to build an ordinary DLL with Visual Studio (at least the 2005 one), you may choose Win32 project and then DLL in the Application Settings window.
Smile | :)

6kyAngel17-Jun-09 18:13

6kyAngel

17-Jun-09 18:13

Hi,

I already download the example code and try to connect to MySQL using "mysql-connector-c++-noinstall-1.0.5-win32-vs2005".

The problem that I'm facing is, I can't even compile the code-error:

fatal error C1083: Cannot open include file: 'mysql.h': No such file or directory

The example program that I used is as below. I already change the setting, include the HEADER file and INCLUDE file while compiling, but still got error.:

///////////////////////////////////////////////////////////////////////////////////////
//// mysqlplus.cpp
///////////////////////////////////////////////////////////////////////////////////////

#include "mysqlplus.h"

#include <stdio.h>

///////////////////////////////////////////////////////////////////////////////////////
//// sql_connection_c

sql_connection_c::sql_connection_c()
{
   host = user = password = database = 0;
   opendbbase = 0;
   errc = 0;
}

sql_connection_c::sql_connection_c( char *__database, char *__host, char *__user, char *__password )
{
   host = user = password = database = 0;
   opendbbase = 0;
   errc = 0;

   connect( __database, __host, __user, __password );
}

sql_connection_c::~sql_connection_c()
{
   if ( host )
   {
	   delete[] host;
      host = 0;
   }

   if ( user )
   {
	   delete[] user;
      user = 0;
   }

   if ( password )
   {
	   delete[] password;
      password = 0;
   }
   if ( database )
   {
	   delete[] database;
      database = 0;
   }

   OPENDB *odb;
	for ( odb = opendbbase; odb; odb = odb->next )
   {
      mysql_close( &odb->mysql );
   }

   while ( opendbbase )
   {
	   odb = opendbbase;
	   opendbbase = opendbbase->next;
	   if ( odb -> busy )
      {
		   //fprintf(stderr,"destroying Database object before Connect object(s)\n");
      }

	   delete odb;
   }
}

///////////////////////////////////////////////////////////////////////////////////////

void sql_connection_c::connect( char *__database, char *__host, char *__user, char *__password )
{
   host = new char[ strlen( __host ) + 1 ];
   strcpy( host, __host );
   
   if ( __user )
   {
      user = new char[ strlen( __user ) + 1 ];
      strcpy( user, __user );
   }
   if ( __password )
   {
      password = new char[ strlen( __password ) + 1 ];
      strcpy( password, __password );
   }

   database = new char[ strlen( __database ) + 1 ];
   strcpy( database, __database );

   freedb( grabdb() ); //// open one connection
}

///////////////////////////////////////////////////////////////////////////////////////

OPENDB *sql_connection_c::grabdb()
{
   OPENDB *odb;
   for ( odb = opendbbase; odb; odb = odb->next )
   {
      if ( !odb->busy )
      {
         break;
      }
   }

   if ( !odb )
   {
	   odb = new OPENDB;
	   if ( !mysql_init( &odb->mysql ) )
	   {
		   //fprintf( stderr, "mysql_init() failed\n" );
		   errc = 1;
	   }
	   if ( !mysql_connect( &odb->mysql, host, user, password ) )
	   {
		   //fprintf( stderr, "mysql_connect(%s,%s,***) failed\n", host, user );
		   errc = 2;
	   }
	   if ( mysql_select_db( &odb->mysql, database ) )
	   {
		   //fprintf( stderr, "mysql_select_db(%s,%s,%s,%s) failed\n", host, user, password, database );
		   errc = 3;
	   }

	   odb->busy = 1;
	   odb->next = opendbbase;
	   opendbbase = odb;
   }
   else
   {
      odb->busy++;
   }

   return odb;
}

void sql_connection_c::freedb( OPENDB *odb )
{
   odb->busy = 0;
}

short sql_connection_c::errcode()
{
   return errc;
}

///////////////////////////////////////////////////////////////////////////////////////
//// sql_query_c

sql_query_c::sql_query_c()
{
   sql_connection = 0;
   odb = 0;
   res = 0;
   row = 0;

   results.set_size( 0 );
}

sql_query_c::sql_query_c( sql_connection_c *__sql_connection )
{
   sql_connection = __sql_connection;
   odb = sql_connection->grabdb();
   res = 0;
   row = 0;

   results.set_size( 0 );
}

sql_query_c::sql_query_c( sql_connection_c *__sql_connection, char *sql )
{
   sql_connection = __sql_connection;
   odb = sql_connection->grabdb();
   res = 0;
   row = 0;

   try_execute( sql );

   results.set_size( 0 );
}

sql_query_c::~sql_query_c()
{
   for ( int idx = 0; idx < results.n_items(); idx++ )
   {
      delete results[ idx ];
      results[ idx ] = 0;
   }

   if ( res )
   {
	   mysql_free_result( res );
   }

   if ( odb )
   {
	   sql_connection->freedb( odb );
   }
}

///////////////////////////////////////////////////////////////////////////////////////

int sql_query_c::try_execute( char *sql )
{
   if ( sql_connection && odb && !res )
   {
	   if ( !mysql_query( &odb->mysql, sql ) )
      {
         return 1;
      }
   }

   return 0;
}

int sql_query_c::execute( char *sql )
{
   if ( sql_connection && odb && !res )
   {
	   if ( try_execute( sql ) )
      {
		   res = mysql_store_result( &odb->mysql );
      }
   }

   return (int)res;
}

sql_result_c *sql_query_c::store()
{
   if ( !res )
   {
      return 0;
   }

   sql_result_c *p = new sql_result_c( this, res );
   results.add( p );

   res = 0; //// prevent someone else from freeing this block

   return p;
}

void sql_query_c::free_result( sql_result_c *sql_result )
{
   for ( int idx = 0; idx < results.n_items(); idx++ )
   {
      if ( results[ idx ] == sql_result )
      {
         delete results[ idx ];
         results[ idx ] = 0;
         results.del( idx );
         break;
      }
   }
}

void sql_query_c::free_result()
{
   if ( sql_connection && odb && res )
   {
	   mysql_free_result( res );
	   res = 0;
	   row = 0;
   }
}

///////////////////////////////////////////////////////////////////////////////////////

__int64 sql_query_c::insert_id()
{
   if ( sql_connection && odb )
   {
	   return mysql_insert_id( &odb->mysql );
   }

   return -1;
}

///////////////////////////////////////////////////////////////////////////////////////

MYSQL_FIELD *sql_query_c::fetch_field()
{
   if ( sql_connection && odb && res )
   {
      return mysql_fetch_field( res );
   }

   return 0;
}

char *sql_query_c::fetch_fieldname()
{
   MYSQL_FIELD *field = 0;

   if ( sql_connection && odb && res )
   {
      field = mysql_fetch_field( res );
   }

   return field ? field->name : "";
}

///////////////////////////////////////////////////////////////////////////////////////

int sql_query_c::ping()
{
   if ( odb )
   {
      return mysql_ping( &odb->mysql );
   }

   return -1;
}

///////////////////////////////////////////////////////////////////////////////////////
//// sql_var_c

sql_var_c::sql_var_c()
{
   value = 0;
}

sql_var_c::sql_var_c( int i )
{
   value = 0;
   *this = i;
}

sql_var_c::sql_var_c( double d )
{
   value = 0;
   *this = d;
}

sql_var_c::sql_var_c( char *s )
{
   value = 0;
   *this = s;
}

sql_var_c::sql_var_c( const char *s )
{
   value = 0;
   *this = (char *)s;
}

sql_var_c::~sql_var_c()
{
   release();
}

///////////////////////////////////////////////////////////////////////////////////////

sql_var_c::operator int ()
{
   if ( !value )
   {
      return 0;
   }

   return atoi( value );
}

sql_var_c::operator double ()
{
   if ( !value )
   {
      return 0;
   }

   return atof( value );
}

sql_var_c::operator char * ()
{
   return value;
}

sql_var_c::operator const char * ()
{
   return value;
}

///////////////////////////////////////////////////////////////////////////////////////

sql_var_c::operator = ( int i )
{
   release();

   value = new char [ 11 + 1 ];
   itoa( i, value, 10 );
}

sql_var_c::operator = ( double d )
{
   release();

   value = new char [ 32 ];
   sprintf( value, "%15.5f", d );
}

sql_var_c::operator = ( char *s )
{
   release();

   value = new char [ strlen( s ) + 1 ];
   strcpy( value, s );
}

sql_var_c::operator = ( const char *s )
{
   *this = (char *)s;
}

///////////////////////////////////////////////////////////////////////////////////////

void sql_var_c::release()
{
   if ( value )
   {
      delete[] value;
      value = 0;
   }
}

///////////////////////////////////////////////////////////////////////////////////////
//// sql_row_c

sql_row_c::sql_row_c()
{
   row = 0;
   __allow_null = 1; //// by default, return null values
}

sql_row_c::sql_row_c( MYSQL_ROW __row )
{
   row = __row;
   __allow_null = 1; //// by default, return null values
}

///////////////////////////////////////////////////////////////////////////////////////

void sql_row_c::allow_null( int allow )
{
   __allow_null = allow;
}

///////////////////////////////////////////////////////////////////////////////////////

sql_var_c sql_row_c::operator [] ( int idx )
{
   return sql_var_c( __allow_null ? ( row[ idx ] ) : ( row[ idx ] ? row[ idx ] : "" ) );
}

///////////////////////////////////////////////////////////////////////////////////////
//// sql_field_c

sql_field_c::sql_field_c()
{
   field = 0;
}

sql_field_c::sql_field_c( MYSQL_FIELD *__field )
{
   field = __field;
}

///////////////////////////////////////////////////////////////////////////////////////

char *sql_field_c::get_name()
{
   return field->name;
}

char *sql_field_c::get_default_value()
{
   return field->def;
}

enum_field_types sql_field_c::get_type()
{
   return field->type;
}

unsigned int sql_field_c::get_max_length()
{
   return field->max_length;
}

///////////////////////////////////////////////////////////////////////////////////////
//// sql_result_c

sql_result_c::sql_result_c()
{
   query = 0;
   res = 0;
}

sql_result_c::sql_result_c( sql_query_c *__query, MYSQL_RES *__res )
{
   query = __query;
   res = __res;
}

sql_result_c::~sql_result_c()
{
   if ( res )
   {
	   mysql_free_result( res );
   }
}

///////////////////////////////////////////////////////////////////////////////////////

__int64 sql_result_c::n_rows()
{
   if ( query && res )
   {
      return mysql_num_rows( res );
   }

   return 0;
}

sql_row_c sql_result_c::fetch_row()
{
   MYSQL_ROW row = mysql_fetch_row( res );

   return sql_row_c( row );
}

///////////////////////////////////////////////////////////////////////////////////////

unsigned int sql_result_c::n_fields()
{
   if ( query && res )
   {
      return mysql_num_fields( res );
   }

   return 0;
}

sql_field_c sql_result_c::fetch_field( unsigned int field_idx )
{
   if ( query && res )
   {
      MYSQL_FIELD *field = mysql_fetch_field_direct( res, field_idx );
      return sql_field_c( field );
   }

   return sql_field_c();
}

Re: How to Connect C++ code with MySQL

CPallini17-Jun-09 21:36