Block the execution of selected functions in a macro.

[Adam Lubszczyk]

Is it possible to block the execution of selected functions in a macro?

Sample in my app I call:

FERASE("temp.dbf")

x:=SIN(2)

So functions FERASE() and SIN() is add to SYMBOLS table and now is possible to execute:

x:="5+SIN(0.2)"

? &(x)   // OK

x:="5+MyStaticFun()"

? &(x)   // RTE unknown function MYSTATICFUN() - OK

but

x:="5+FERASE('baza.dbf')"

? &(x)   // OK - but I want RTE unknown function FERASE()

May be like STATIC FINCTION ...

STATIC REQUEST ferase,run,dbcreate,...

Adam

[Antonio Linares]

Adam,

You can replace the pcode pointers of those functions and redirect them to a dummy function

regards

[Lailton Fernando Mariano]

REQUEST FERASE, RUN, DBCREATE

It?

[Adam Lubszczyk]

piątek, 4 listopada 2022 o 09:14:56 UTC+1 lai...@paysoft.com.br napisał(a):

REQUEST FERASE, RUN, DBCREATE

It?

Maybe like command STATIC MyFun()

I can use MyFun() in source prg but not in macro

You add command like:

STATIC REQUEST FERASE, __RUN, DBCREATE

Now I can use FERASE() , __RUN(), DBCREATE() in source prg but not in macro.

Adam

[Adam Lubszczyk]

piątek, 4 listopada 2022 o 07:50:07 UTC+1 Antonio Linares napisał(a):

Adam,

You can replace the pcode pointers of those functions and redirect them to a dummy function

How? An example please.

 Adam

[Antonio Linares]

dummy.c

#define _HB_API_INTERNAL_
#include <hbapi.h>

HB_FUNC( REPLACEPCODE )
{
   PHB_DYNS pDynSymOne = hb_dynsymFind( "ONE" );
   PHB_DYNS pDynSymTwo = hb_dynsymFind( "TWO" );
   PHB_DYNS pDynSymDummy = hb_dynsymFind( "DUMMY" );

   pDynSymOne->pSymbol->value.pCodeFunc = pDynSymDummy->pSymbol->value.pCodeFunc;
   pDynSymTwo->pSymbol->value.pCodeFunc = pDynSymDummy->pSymbol->value.pCodeFunc;
}

example of use:

function Main()

   One()
   Two()

   ReplacePcode()

   One()
   Two()

return nil
   
function One()

   ? "one"

return nil

function Two()

   ? "two"

return nil

function Dummy()

   ? "this is a dummy function"

return nil

output:

one
two
this is a dummy function
this is a dummy function

regards

[Antonio Linares]

For Harbour function that don't use pcode, then you have to do it this way:

dummy.c

#define _HB_API_INTERNAL_
#include <hbapi.h>

void dummy( void )
{
   hb_retc( "I am a dummy function" );
}

HB_FUNC( CHANGEDATE )
{
   PHB_DYNS pDynSymDate = hb_dynsymFind( "DATE" );

   pDynSymDate->pSymbol->value.pFunPtr = dummy;
}

example of use:

function Main()

   ? Date()
 
   ChangeDate()

   ? Date()

return nil

output:

11/05/22
I am a dummy function

So before you allow the user to write a macro, you can modify the Harbour functions that you don't want the user to use, and after that you can restore the original values.

You can save the pFunPtr old values in C static values, and reload them

regards

[Antonio Linares]

Better this way:

dummy.c

#define _HB_API_INTERNAL_

#include <hbapi.h>

HB_FUNC( DUMMY )

{

   hb_retc( "I am a dummy function" );

}

HB_FUNC( CHANGEDATE )

{

   PHB_DYNS pDynSymDate = hb_dynsymFind( "DATE" );

   pDynSymDate->pSymbol->value.pFunPtr = HB_FUN_DUMMY;

}

regards

[Adam Lubszczyk]

sobota, 5 listopada 2022 o 10:35:23 UTC+1 Antonio Linares napisał(a):

[...]

Thank you for the hint.

I try set function scope to HB_FS_STATIC  but now work.

In the end, I chose this:

dummy.c

#define _HB_API_INTERNAL_
#include <hbapi.h>

static char * dummy = "*" ;

HB_FUNC( CHANGEDATE )
{
   PHB_DYNS pDynSymDate = hb_dynsymFind( "DATE" );

   if (  pDynSymDate )
     pDynSymDate->pSymbol->szName = dummy  ;
}

example of use:

function Main()
  a := "Date()"
   ? Date()
   ? &(a)
   ? "CHANGE"  

   ChangeDate()
   ? Date()

   ? &(a)

return

Output:

11/07/22
11/07/22
CHANGE
11/07/22
Error BASE/1001  Undefined function: DATE

Adam

[Francesco Perillo]

What about scanning the macro text for function names?