DESCRIPTION

Register callback function to Boolean expression evaluator. The function name which appears in UBF expression is set in funcname argument in callback. The callback function by it is self is set in functionPtr. The callback function receives the buffer on which it is being evaluated in p_ub, and callback receives the function name too in funcname.

In case if using Bboolsetcbf2() additionally arg1 argument is received from Boolean expression script.

Min length for function name is 1 symbols and max length is 64.

Min arg1 length is 0 (just two single quotes) and arg1 length is 510.

Example:

long callback_no_args(UBFH *p_ub, char *funcname)
{
    return 888;
}

long callback_with_args(UBFH *p_ub, char *funcname, char *arg1)
{
    if (0==strcmp(arg1, "OK"))
     return 0;
    else
     return 1;
}


Bboolsetcbf ("callback_no_args", callback_no_args);

Bboolsetcbf2 ("callback_with_args", callback_with_args);

tree=Bboolco ("callback_no_args()==888 && callback_with_args('OK')==0 && callback_with_args('NOK')==1");

If calling Bboolsetcbf() or Bboolsetcbf2() with NULL function pointer, the function is removed from callback mappings. But this cannot be done in case if some tree is already compiled, as it holds the pointer to function map entry and this pointer is compiled tree is not reset. This shall be controlled by developer, otherwise if removing mapping for already compiled tree and tree is being evaluated, the segmentation fault is possible.

arg1 for Bboolsetcbf2() is passed in callback function in single quotes. The single quotes cannot be escaped, other C escapes are not processed too. Argument data escaping is subject for future changes.

RETURN VALUE

On success, Bboolsetcbf() returns 0. On error -1 is returned, with Berror set to indicate the error.

ERRORS

Note that Bstrerror() returns generic error message plus custom message with debug info from last function call.

BBADNAME Invalid function name

EXAMPLE

See ubftest/test_expr.c for sample code.

BUGS

Report bugs to support@mavimax.com

SEE ALSO

Bboolco(3) Bfloatev(3) Btreefree(3)

COPYING

© Mavimax, Ltd