[PATCHv2 1/2] gdb/python: add gdb.host_charset function

[Andrew Burgess]

Thanks for the reviews.  I pushed this patch.  I'm holding off on
patch 2/2 to give more folk a chance to comment.

Thanks,
Andrew

* Andrew Burgess <aburgess@redhat.com> [2022-01-12 14:30:27 +0000]:

> We already have gdb.target_charset and gdb.target_wide_charset.  This
> commit adds gdb.host_charset along the same lines.
> ---
>  gdb/NEWS                                |  3 ++
>  gdb/doc/python.texi                     |  8 ++++
>  gdb/python/python.c                     | 13 +++++++
>  gdb/testsuite/gdb.python/py-charset.exp | 50 +++++++++++++++++++++++++
>  4 files changed, 74 insertions(+)
>  create mode 100644 gdb/testsuite/gdb.python/py-charset.exp
> 
> diff --git a/gdb/NEWS b/gdb/NEWS
> index c1f30563a93..8c13cefb22f 100644
> --- a/gdb/NEWS
> +++ b/gdb/NEWS
> @@ -143,6 +143,9 @@ show debug lin-lwp
>       is equivalent to the existing 'maint packet' CLI command; it
>       allows a user specified packet to be sent to the remote target.
>  
> +  ** New function gdb.host_charset(), returns a string, which is the
> +     name of the current host charset.
> +
>  * New features in the GDB remote stub, GDBserver
>  
>    ** GDBserver is now supported on OpenRISC GNU/Linux.
> diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
> index 6bd5f6b90ac..38fce5b38e3 100644
> --- a/gdb/doc/python.texi
> +++ b/gdb/doc/python.texi
> @@ -518,6 +518,14 @@
>  never returned.
>  @end defun
>  
> +@findex gdb.host_charset
> +@defun gdb.host_charset ()
> +Return a string, the name of the current host character set
> +(@pxref{Character Sets}).  This differs from
> +@code{gdb.parameter('host-charset')} in that @samp{auto} is never
> +returned.
> +@end defun
> +
>  @findex gdb.solib_name
>  @defun gdb.solib_name (address)
>  Return the name of the shared library holding the given @var{address}
> diff --git a/gdb/python/python.c b/gdb/python/python.c
> index e05b99c0bec..4dcda53d9ab 100644
> --- a/gdb/python/python.c
> +++ b/gdb/python/python.c
> @@ -571,6 +571,16 @@ gdbpy_target_wide_charset (PyObject *self, PyObject *args)
>    return PyUnicode_Decode (cset, strlen (cset), host_charset (), NULL);
>  }
>  
> +/* Implement gdb.host_charset().  */
> +
> +static PyObject *
> +gdbpy_host_charset (PyObject *self, PyObject *args)
> +{
> +  const char *cset = host_charset ();
> +
> +  return PyUnicode_Decode (cset, strlen (cset), host_charset (), NULL);
> +}
> +
>  /* A Python function which evaluates a string using the gdb CLI.  */
>  
>  static PyObject *
> @@ -2281,6 +2291,9 @@ Return the name of the current target charset." },
>    { "target_wide_charset", gdbpy_target_wide_charset, METH_NOARGS,
>      "target_wide_charset () -> string.\n\
>  Return the name of the current target wide charset." },
> +  { "host_charset", gdbpy_host_charset, METH_NOARGS,
> +    "host_charset () -> string.\n\
> +Return the name of the current host charset." },
>    { "rbreak", (PyCFunction) gdbpy_rbreak, METH_VARARGS | METH_KEYWORDS,
>      "rbreak (Regex) -> List.\n\
>  Return a Tuple containing gdb.Breakpoint objects that match the given Regex." },
> diff --git a/gdb/testsuite/gdb.python/py-charset.exp b/gdb/testsuite/gdb.python/py-charset.exp
> new file mode 100644
> index 00000000000..e4af0e5b56f
> --- /dev/null
> +++ b/gdb/testsuite/gdb.python/py-charset.exp
> @@ -0,0 +1,50 @@
> +# Copyright 2022 Free Software Foundation, Inc.
> +
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +
> +load_lib gdb-python.exp
> +
> +gdb_exit
> +gdb_start
> +
> +# Skip all tests if Python scripting is not enabled.
> +if { [skip_python_tests] } { continue }
> +
> +# Each test data has 4 parts:
> +# 1. The string used in 'show XXX-charset' command,
> +# 2. The string expected in the output of the command used in #1,
> +# 3. The string used is gdb.XXXX_charset() python function call,
> +# 4. A string that is a regexp appended to the result of #1, used to
> +#    match the output of #3
> +foreach test_data { {host host host ""} \
> +			{target target target ""} \
> +			{target-wide "target wide" \
> +			     "target_wide" "(LE|BE)?"} } {
> +    with_test_prefix "charset=[lindex $test_data 0]" {
> +	set charset "unknown"
> +	gdb_test_multiple "show [lindex $test_data 0]-charset" "" {
> +	    -re "The [lindex $test_data 1] character set is \"auto; currently (\[^\"\]*)\".*$gdb_prompt $" {
> +		set charset $expect_out(1,string)
> +		pass $gdb_test_name
> +	    }
> +	    -re "The [lindex $test_data 1] character set is \"(\[^\"\]*)\".*$gdb_prompt $" {
> +		set charset $expect_out(1,string)
> +		pass $gdb_test_name
> +	    }
> +	}
> +	set charset "${charset}[lindex $test_data 3]"
> +	gdb_test "python print(gdb.[lindex $test_data 2]_charset())" \
> +	    "${charset}"
> +    }
> +}
> -- 
> 2.25.4
>