[Plplot-devel] Plplot Ada binding

[Bernard W. <Ber...@wa...>]

Hi,

For my personal use I needed to have an Ada binding to the Plplot 5.0.3
plotting library. So I developped such a binding with a reduced set of
interface functions.

As a small contribution to the overall product I send this binding with
2 simple testing programs that perhaps you will find interesting for
somebody else. Feel free to use them as you wish.

While porting the Plplot core source on another UNIX computer, I found a
small bug in the stripchart management, in the c_plstripa() function,
which produces a SIGSEGV error. The context of the error is at line 252
of file plstripc.c:

                plcol(stripc->colline[p]); pllsty(stripc->styline[p]);
                plP_movwor(stripc->x[p][stripc->npts[p]-2],
stripc->y[p][stripc->npts[p]-2]);            <----------- here
                plP_drawor(stripc->x[p][stripc->npts[p]-1],
stripc->y[p][stripc->npts[p]-1]);
                plflush();

For the first call to the c_plstripa function, stripc->npts[p]-2 value
is -1 and generates an out of bound access in table stripc->x[p].

I personally replaced the line:

                plP_movwor(stripc->x[p][stripc->npts[p]-2],
stripc->y[p][stripc->npts[p]-2]);

by:

                if ((stripc->npts[p]-2) < 0)
                        plP_movwor(0.0, 0.0) ;
                else
                        plP_movwor(stripc->x[p][stripc->npts[p]-2],
stripc->y[p][stripc-npts[p]-2]);

I hope this will help.