Re: [PATCH, master + 11][gdb/cli] Don't assert on empty string for core-file

[Andrew Burgess <andrew.burgess@embecosm.com>]

* Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> [2021-08-30 12:32:25 +0200]:

> Hi,
> 
> With current gdb we run into:
> ...
> $ gdb -batch '' ''
> : No such file or directory.
> pathstuff.cc:132: internal-error: \
>   gdb::unique_xmalloc_ptr<char> gdb_abspath(const char*): \
>   Assertion `path != NULL && path[0] != '\0'' failed.
> ...
> 
> Fix this by skipping the call to gdb_abspath in core_target_open in the
> empty-string case, such that we have instead:
> ...
> $ gdb -batch '' ''
> : No such file or directory.
> : No such file or directory.
> $
> ...
> 
> Tested on x86_64-linux.
> 
> Any comments?

The error messages aren't massively helpful, but I'm not convinced its
worth putting too much effort into making them more hopeful, so LGTM.

Thanks,
Andrew

> 
> Thanks,
> - Tom
> 
> [gdb/cli] Don't assert on empty string for core-file
> 
> gdb/ChangeLog:
> 
> 2021-08-30  Tom de Vries  <tdevries@suse.de>
> 
> 	PR cli/28290
> 	* gdb/corelow.c (core_target_open): Skip call to gdb_abspath in the
> 	empty-string case.
> 
> gdb/testsuite/ChangeLog:
> 
> 2021-08-30  Tom de Vries  <tdevries@suse.de>
> 
> 	PR cli/28290
> 	* gdb.base/batch-exit-status.exp: Add gdb '' and gdb '' '' tests.
> 
> ---
>  gdb/corelow.c                                | 3 ++-
>  gdb/testsuite/gdb.base/batch-exit-status.exp | 4 ++++
>  2 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/gdb/corelow.c b/gdb/corelow.c
> index eb785a08633..711e86c4cd4 100644
> --- a/gdb/corelow.c
> +++ b/gdb/corelow.c
> @@ -428,7 +428,8 @@ core_target_open (const char *arg, int from_tty)
>      }
>  
>    gdb::unique_xmalloc_ptr<char> filename (tilde_expand (arg));
> -  if (!IS_ABSOLUTE_PATH (filename.get ()))
> +  if (strlen (filename.get ()) != 0
> +      && !IS_ABSOLUTE_PATH (filename.get ()))
>      filename = gdb_abspath (filename.get ());
>  
>    flags = O_BINARY | O_LARGEFILE;
> diff --git a/gdb/testsuite/gdb.base/batch-exit-status.exp b/gdb/testsuite/gdb.base/batch-exit-status.exp
> index 085dfc6ad56..9a080196bd6 100644
> --- a/gdb/testsuite/gdb.base/batch-exit-status.exp
> +++ b/gdb/testsuite/gdb.base/batch-exit-status.exp
> @@ -76,3 +76,7 @@ test_exit_status 1 "-batch -x $good_commands -x $bad_commands" \
>      "-batch -x good-commands -x bad-commands"
>  test_exit_status 1 "-batch -x $good_commands -ex \"set not-a-thing 4\"" \
>      "-batch -x good-commands -ex \"set not-a-thing 4\""
> +
> +set no_such_re ": No such file or directory\\."
> +test_exit_status 1 "-batch \"\"" $no_such_re
> +test_exit_status 1 "-batch \"\" \"\"" [multi_line $no_such_re $no_such_re]