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

[Andrew Burgess <aburgess@redhat.com>]

Craig Blackmore <craig.blackmore@embecosm.com> writes:

> 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`?

Yes, I only learned about 'set print symbol-filename' during the doc
review, and neglected to add a new test.

I've posted a V2 patch which include a new test for this.

Thanks,
Andrew