Re: [MI] -file-list-exec-source-files

[Bob Rossi <bob at brasko dot net>]

On Tue, Feb 17, 2004 at 02:47:55PM -0500, Andrew Cagney wrote:
> >On Tue, Feb 17, 2004 at 02:12:38PM -0500, Daniel Jacobowitz wrote:
> >
> >>On Tue, Feb 17, 2004 at 02:10:05PM -0500, Bob Rossi wrote:
> >
> >>> I have one last question that didn't get answered, could the psymtab be
> >>> modified to contain the dirname?
> >
> >>
> >>Probably, but the dirname -> fullname conversion may be expensive - it
> >>involves a lot of stat() calls.
> >
> 
> As a first cut, don't worry about performance (or more correctly 
> scaleability).   Just correctness (especially of the symtab interface).

Ok.

> 
> >2. -file-list-exec-fetch-fullname [filename]
> >
> >   This will be a new MI command.
> >
> >   This will return a fullname given a filename.
> >   If the symtab is read in, it calls source.c:symtab_to_filename.
> >   If the symtab is not read in, it reads it in and calls the above
> >   function.
> >
> >   This function is necessary because all of the other MI commands still
> >   output just the filename and not the fullname. For example, breakpoints,
> >   stack, ...

Yes, I guess it's a bug. However, these commands have never returned the 
fullname. 

Here you are making a big change to the way GDB deals with front ends.
You are saying that GDB should only let the front end know about
fullnames, and know nothing about filenames.

I consider this desirable as a front end writer, since the fullname is
the only valid unique key to a front end.

It would be nice if I could do this in 2 phase's. 
First add this function, for backwards compatibility, and then, change
all the existing commands to return fullnames.

Although, leaving this function around, doesn't hurt anything.

> >3. -file-list-exec-source-files [force_fullnames]
> >
> >   This will implement an existing unimplemented MI command.
> >
> >   By default, this will return 
> >   1. filename for each psymtab, with no fullname
> >   2. filename/fullname for each symtab
> >
> >   If the option "force_fullnames" is passed, it will have GDB convert all
> >   of the psymtabs to symtabs, thus printing out the filename/fullname for 
> >   all symtabs. The overhead of doing this is probably high, and
> >   undesirable by default.
> >
> >   If the front end wants to be more efficient, it could show the user the
> >   "filenames" and then do the "fullname" lookup just on that file. Thus,
> >   only reading in one symtab.
> 
> This specification is too heavily dependent on GDB's current underlying 
> implementation - symtab and psymtab are internal details and do not 
> belong in this interface specification.

I was just showing how this interface is affected by GDB's
implementation of psymtab/symtab. The user will have no idea of these 2
concepts.

Anyways, if I can get the dirname into psymtab, this will no longer be an 
issue. The user will always get the filename/fullname combo.

With that said, do you like the implementation?

Thanks,
Bob Rossi