GDB TUI doesn't build

[Andrew Cagney <ac131313 at cygnus dot com>]

[I had several requests for this so I'm going to add it to the gdb/TODO
file].

For those that are interested, my list of TUI problems are below.

There is also a more general issue.  I know HP have an in-house version
of the TUI.  It might be easiest to replace the current public version
with HP's (even if it still doesn't build) and then start on bring it up
to scratch.

Fix TUI

     o  readline/*.h bitrot

        The TUI isn't up-to-date with
        respect to the readline currently
        bundled with GDB.  Importing a
        new readline is on the 5.1 wish
        list so this can only get worse.

        Grep for things like term_cursor_move.

        (To be honest, I don't see anyone
        importing a new readline before 5.1 is
        out)

     o  tui.c:va_catch_errors() bitrot

        This nasty piece of work used knowledge
        of the internals of GDBs error functions :-(
        Ever since those internals were cleaned
        up this code has been broken. :-(

     o  tuiWin.c:c_makeVisibleWithNewHeight() broken
        tuiLayout.c:_extractDisplayStartAddr() broken

        Both these function call find_line_pc()
        incorrectly (wrong args, wrong return value).

        I suspect this bug has always been there!
        It had been hidden because those files
        didn't include the necessary header files
        from gdb proper :-(

     o  tuiRegs() host dependant

        Not suprisingly, this isn't a very portable
        section of code.  However, I'm sure people
        could live with no regs in the short to
        medium term.

     o  defs.h: #include "tui.h" et.al.

        I'm not sure where this came from.
        It was a really bad idea.

        To get things to compile I did a nasty
        hack (Just declare what was needed and
        replace any expressions like xx->y.z()
        in GDB proper with function calls).  I
        could commit it slightly cleaned up if
        you like.

        Medium Term. the #ifdef TUI and TuiDo()
        should be changed to hooks (like GDBTK).
        The gdb-events.[hc] is there for that
        purpose (1)

     o  tui.c:_tuiReset() host dependant

        tui.c contains a lump of termio[s]
        I suspect an equivalent block of
        code can be lifted from readline.
        An equivalent readline function may
        even be available.

     o  curses.h vs ncurses.h.

        Simple portability problem.

     o  subsetCompare()

        This function is a mystery - where is it?

     o  tui-file.[hc] cleanup

        This can be significantly simplified.

     o  The code should be pacified. (-Werror -W...)

        There are plenty of #includes,
        duplicate #includes, missing function decls
        and the like.

        Some of the problems I found were through
        fixing a few of the warnings.

     o  The code should be GNUtified.

        It would be very nice to have this code
        look like the rest of GDB.  That way people
        would be more accepting of it as a true
        gdb component.

        Until it is GNUtified it is going to stick
        out like a sore thumb to the programmer.

     o  The code should be clearly copyrighted

        (FSF, with due credit to HP)