DESCRIPTION

Print the compiled UBF buffer boolean expression evaluation Abstract Syntax Tree (AST) at tree hander to p_writef callback function. The sample output for AST is following:

int writef(char *buffer, long datalen, void *dataptr1)
{
    /* in total this will get buffer fragments like
     * ((2*(4+5)) || ((5 && ('abc' %% '..b')) && (((2/2)*4) == 5))
     * note there could be newlines (\n) between calls
     */
    return 0;
}

...
tree=Bboolco ("2 * ( 4 + 5 ) || 5 && 'abc' %% '..b' && 2/2*4==5")
...
Bboolprcb(tree, writef, NULL);

The callback function will called several times as portions of the AST are traversed with each call line is terminated with EOS (0x00 byte) symbol. The compiled tree to function is presented by tree argument, the callback is set by p_writef function. Function accepts optional dataptr1 argument which is user pointer forwarded to p_writef callback. The dataptr1 can be NULL.

The p_writef by it self receives buffer which contains ASCII chars of the AST representation, datalen includes the data buffer received (note EOS are note included in intermediate calls). The dataptr1 is user pointer passed to Bboolprcb(). In case of success the callback shall return 0, and in cases of failure a non zero value. When error occurs, the function terminates the printing.

The last call to printing includes newline and then 0x00 follows.

RETURN VALUE

Function is void and does not return any value.

ERRORS

Function is void and does not return any error.

EXAMPLE

See ubftest/test_expr.c for sample code.

BUGS

Report bugs to support@mavimax.com

SEE ALSO

Bboolpr(3) Bboolev(3) Bfloatev(3) Btreefree(3)

COPYING

© Mavimax, Ltd