[PATCH 0/5] Change how "target:" gets into filenames

[Gary Benson <gbenson at redhat dot com>]

Hi all,

This is a continuation of this thread:
https://sourceware.org/ml/gdb/2015-07/msg00038.html

In summary, GDB since April automatically locates and fetches
binary files from remote systems.  A number of people would
like this not to happen.

This automation hinged on changing the default sysroot from ""
to "target:".  This series reverts that change, and instead
updates solib_find_1 to use "target:" as the sysroot where it
would be necessary to access the files.

Most use cases proceed as before, but with this series the
files are *not* transferred if you supply GDB an executable
either on the command line or with a "file" command.

Remote examples:

  $ gdb ./a.out
  (gdb) target remote :9999
  # no "target:" prefix (=no files transferred)

  $ gdb
  (gdb) file a.out
  (gdb) target remote :9999
  # no "target:" prefix (=no files transferred)

  $ gdb
  (gdb) target remote :9999
  # "target:" prefix, files transferred

Aside from fixing this issue, GDB with this change has the advantage
that users don't see the "target:" prefix unless either they are
using GDB in a way that didn't work in 7.9 (remote target without
"file" and "set sysroot" commands, containerized target) or they
explitictly set it themselves (e.g. "set sysroot target:/foo/bar").

I've Cc'd Joel because, if this is the way we want to go, it would
be nice to have this in 7.10 as it minimises the difference from
7.9 and would avoid having 7.10 introduce the "target:" sysroot
only for 7.11 to remove it.

I've Cc'd Jan because he's working on making sysroot be a search
path. (defaulting to something like "/", "target:/").  I think you
could do that from this series by treating the auto-target-prefix
boolean as a stepping-stone that could be removed.  If nothing else
this series is a map of the places you'll need to update :)

Built and regtested on RHEL 6.6 x86_64.

Opinions?  (Should I commit this, and if so where?)

Cheers,
Gary

--
http://gbenson.net/