Re: [PATCH] gdb/python: add gdb.Architecture.format_address

[Craig Blackmore <craig.blackmore@embecosm.com>]

Hi Andrew,

On 22/02/2022 13:56, Andrew Burgess via Gdb-patches wrote:
> Eli Zaretskii <eliz@gnu.org> writes:
>
>>> From: Andrew Burgess <aburgess@redhat.com>
>>> Cc: gdb-patches@sourceware.org
>>> Date: Mon, 21 Feb 2022 17:27:21 +0000
>>>
>>> I'm certainly not against renaming, if we can come up with a better
>>> name... maybe 'format_address_info'?  I don't know... I still kind of
>>> like 'format_address'...
>> I hope someone will come up with a better name.
format_address seems ok to me and I couldn't come up with anything better.
> diff --git a/gdb/python/py-arch.c b/gdb/python/py-arch.c
> index 0f273b344e4..95ae931e73e 100644
> --- a/gdb/python/py-arch.c
> +++ b/gdb/python/py-arch.c
> @@ -348,6 +348,31 @@ gdbpy_all_architecture_names (PyObject *self, PyObject *args)
>    return list.release ();
>   }
>   
> +/* Implement gdb.architecture.format_address(ADDR).  Provide access to
> +   GDB's print_address function from Python.  The returned address will
> +   have the format '0x..... <symbol+offset>'.  */
> +
> +static PyObject *
> +archpy_format_address (PyObject *self, PyObject *args, PyObject *kw)
> +{
> +  static const char *keywords[] = { "address", nullptr };
> +  PyObject *addr_obj;
> +  CORE_ADDR addr;
> +  struct gdbarch *gdbarch = nullptr;
> +
> +  ARCHPY_REQUIRE_VALID (self, gdbarch);
> +
> +  if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "O", keywords, &addr_obj))
> +    return nullptr;
> +
> +  if (get_addr_from_python (addr_obj, &addr) < 0)
> +    return nullptr;
> +
> +  string_file buf;
> +  print_address (gdbarch, addr, &buf);
> +  return PyString_FromString (buf.c_str ());
> +}
> +
>   void _initialize_py_arch ();
>   void
>   _initialize_py_arch ()
> @@ -391,6 +416,12 @@ group GROUP-NAME." },
>       METH_NOARGS,
>       "register_groups () -> Iterator.\n\
>   Return an iterator over all of the register groups in this architecture." },
> +  { "format_address", (PyCFunction) archpy_format_address,
> +    METH_VARARGS | METH_KEYWORDS,
> +    "format_address (ADDRESS) -> String.\n\
> +Format ADDRESS, an address within the currently selected inferior's\n\
> +address space, as a string.  The format of the returned string is\n\
> +'ADDRESS <SYMBOL+OFFSET>' without the quotes." },
>     {NULL}  /* Sentinel */
>   };
>   
> diff --git a/gdb/testsuite/gdb.python/py-arch.exp b/gdb/testsuite/gdb.python/py-arch.exp
> index b55778b0b72..c4854033d8c 100644
> --- a/gdb/testsuite/gdb.python/py-arch.exp
> +++ b/gdb/testsuite/gdb.python/py-arch.exp
> @@ -127,3 +127,18 @@ foreach a $arch_names b $py_arch_names {
>       }
>   }
>   gdb_assert { $lists_match }
> +
> +# Check the gdb.Architecture.format_address method.
> +set main_addr [get_hexadecimal_valueof "&main" "UNKNOWN"]
> +gdb_test "python print(\"Got: \" + gdb.selected_inferior().architecture().format_address($main_addr))" \
> +    "Got: $main_addr <main>" \
> +    "gdb.Architecture.format_address, result should have no offset"
> +set next_addr [format 0x%x [expr $main_addr + 1]]
> +gdb_test "python print(\"Got: \" + gdb.selected_inferior().architecture().format_address($next_addr))" \
> +    "Got: $next_addr <main\\+1>" \
> +    "gdb.Architecture.format_address, result should have an offset"
> +if {![is_address_zero_readable]} {
> +    gdb_test "python print(\"Got: \" + gdb.selected_inferior().architecture().format_address(0))" \
> +	"Got: 0x0" \
> +	"gdb.Architecture.format_address for address 0"
> +}
>
The code LGTM. Just one query, is it necessary to add a test case for 
printing the filename and line number when we have `set print 
symbol-filename on`?

Thanks,

Craig