The current implementation of gdb_py_tp_name() leaks a reference to the
object returned by PyType_GetFullyQualifiedName() for Python >= 3.13, and
PyType_GetQualName() for Python >= 3.11.
Managing the strong reference on the returned PyObject* with a gdbpy_ref<>
fixes the reference count, but also causes the temporary object to be
deallocated on function exit. As a consequence, the 'const char *' returned
by PyUnicode_AsUTF8AndSize() becomes dangling and can no longer safely be
returned.
The proposed approach consists in changing gdb_py_tp_name() to return a
std::string, and forcing a copy of the 'const char *' value, statically
or dynamically allocated, stored in a temporary or non-temporary PyObject,
depending on the version of Python it was compiled with.
An unfortunate side effect of this fix is that every call sites where the
tp_name is printed, must now use `.c_str()' because PyErr_Format()
and its siblings cannot handle std::string.
Approved-By: Andrew Burgess <aburgess@redhat.com>
All of our custom Python types are created as structs, like this:
struct some_new_type : public PyObject
{
... various fields ...
};
Then instances of this struct are created by calling PyObject_New,
either directly within GDB's C++ code, or within Python when a user's
Python script creates an instance of that class.
The problem is that Python is written in C, and PyObject_New doesn't
call any constructors for `some_new_type`, nor for any of the fields
within `some_new_type`.
If `some_new_type` is Plain Old Data (POD), then this is fine. Or, to
be more C++ specific, if `some_new_type` is trivially default
constructable, then we're fine.
But if a field within `some_new_type` has a non-trivial constructor,
then we're in trouble as that constructor will never be run.
An example of a problematic field type is frame_info_ptr. The
constructor for this type registers the new object with a central
management object, recording the `this` pointer, using this type within
`some_new_type` will not work as expected; frame invalidation will not
show up within the frame_info_ptr as you might expect.
And so, this type trait exists. Whenever a struct is created to define
a new Python type we should add a line like:
static_assert (gdb::is_python_allocatable_v<some_new_type>);
This will fail if any field of `some_new_type` are unsuitable for this
use.
We don't actually check is_trivially_default_constructible here. Some
types, e.g. ui_file_style::color, have non-trivial (or no default)
constructors, but are still safe to use within `some_new_type` because
their constructors just initialise data fields; there's nothing
"special" that the constructor does that cannot be achieved by
assigning the fields after creation with PyObject_New.
What actually matters is that the type is trivially destructible
(Python won't call C++ destructors, so destructors with side effects,
like deregistering from a list, would be skipped) and trivially
copyable (Python may copy objects with memcpy). Types like
frame_info_ptr, whose constructors and destructors have side effects
such as registering with a central management object, will be caught
because they are neither trivially destructible nor trivially copyable.
Simple POD types like ui_file_style are trivially destructible and
copyable, so pass this trait.
This commit adds the new type trait, and makes use of it in all cases
but one, pending_frame_object in python/py-unwind.c, has a field of
type frame_info_ptr, which is currently broken. This will be fixed,
and the static_assert added, in the next commit.
Approved-By: Tom Tromey <tom@tromey.com>
Py_TYPE (self)->tp_name is the traditional idiomatic way to get a Python
type's fully qualified name. However, in the context of the Python
limited API, PyTypeObject is opaque, so the 'tp_name' attribute is no
longer accessible. Additionally, retrieving the type of a Python object
requires Py_TYPE, which is only available as part of the stable API
starting with Python 3.14.
This patch increases minimal Python limited API version from 3.11 to 3.14.
It also introduces two new helpers to retrieve a type's fully qualified
name: gdb_py_tp_name() and gdbpy_py_obj_tp_name(), which extract the fully
qualified name from a PyTypeObject and a PyObject, respectively. Ifdefery
allows these wrappers to select the appropriate API depending on the Python
version and whether the Python limited API is enabled. For any Python
version less than 3.13, gdb_py_tp_name() fallbacks using __qualname__
instead. However, the result may differ slightly in some cases, e.g. the
module name may be missing.
Finally, this patch adapts the existing code to use these wrappers, and
adjusts some test expectations to use the fully qualified name (or
__qualname__ for versions <= 3.13) where it was not previously used.
Note that the corner case where the module name would be missing does not
appear in the testsuite.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23830
Approved-By: Tom Tromey <tom@tromey.com>
Replace all occurrences of:
strcmp (...) == 0
strcmp (...) != 0
!strcmp (...)
0 == strcmp (...)
strcmp (...) directly used as a boolean predicate
with the equivalent expression using streq.
This is for consistency (we already use streq as some places in the
testsuite) but also for clarity. I think that streq is clearer on the
intent than strcmp. It's also a bit shorter.
Change-Id: Ibbf5261b1872c240bc0c982c147f6a5477275a91
Approved-By: Andrew Burgess <aburgess@redhat.com>
Previous patches made some Python extension objects ipublicly inherit
directly or indirectly from PyObject.
In the interest of consistency, this patch makes all remaining Python
extension objects still not inheriting from PyObject do so.
Approved-By: Tom Tromey <tom@tromey.com>
This updates the copyright headers to include 2026. I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
When GDB is built with undefined behavior sanitizer,
gdb.python/py-style.exp fails because of this:
$ ./gdb -q -nx --data-directory=data-directory -ex "python filename_style = gdb.Style('filename')" -ex "python filename_style.intensity = -3"
/home/simark/src/binutils-gdb/gdb/python/py-style.c:239:11: runtime error: load of value 4294967293, which is not a valid value for type 'intensity'
Fix it by casting the value to ui_file_style::intensity only after
validating the raw value.
Change-Id: I38eb471a9cb3bfc3bb8b2c88afa76b8025e4e893
Approved-By: Tom Tromey <tom@tromey.com>
It is already possible to produce styled output from Python by
converting the gdb.Style to its escape code sequence, and writing that
to the output stream.
But this commit adds an alternative option to the mix by extending the
existing gdb.write() function to accept a 'style' argument. The value
of this argument can be 'None' to indicate no style change should be
performed, this is the default, and matches the existing behaviour.
Or the new 'style' argument can be a gdb.Style object, in which case
the specified style is applied only for the string passed to
gdb.write, after which the default style is re-applied.
Using gdb.write with a style object more closely matches how GDB
handles styling internally, and has the benefit that the user doesn't
need to remember to restore the default style when they are done.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
This commit adds a new gdb.Style class. This class represents a
complete style within GDB. A complete style is a collection of
foreground color, background color, and an intensity.
A gdb.Style comes in two flavours, named, and unnamed.
A named style is one that is based on an existing style within GDB.
For example, we have 'set style filename ...', the name of this style
is 'filename'. We also have 'set style disassembler mnemonic ...',
the name of this style is 'disassembler mnemonic'. A named style is
created by passing the name of the style, like this:
(gdb) python s1 = gdb.Style("filename")
(gdb) python s2 = gdb.Style("disassembler mnemonic")
The other type of style is an unnamed style. An unnamed style is
created using a foreground and background color, along with an
intensity. Colors are specified using gdb.Color objects. An example
of creating an unnamed style is:
(gdb) python s3 = gdb.Style(foreground=gdb.Color('red'),
background=gdb.Color('green'),
intensity=gdb.INTENSITY_BOLD)
We can see here an example of the new intensity constants that have
been added in this commit, there is gdb.INTENSITY_NORMAL,
gdb.INTENSITY_BOLD, and gdb.INTENSITY_DIM. All of the arguments are
optional, the default for the colors is gdb.Color(), which will apply
the terminal default, and the default intensity is
gdb.INTENSITY_NORMAL.
Having created a gdb.Style object there are two ways that it can be
used to style GDB's output. The Style.escape_sequence() method
returns the escape sequence needed to apply this style, this can be
used as in:
(gdb) python print(s1.escape_sequence() + "Filename Style")
The problem with this approach is that it is the users responsibility
to restore the style to the default when they are done. In the above
example, all output after the escape sequence is printed, including
the next GDB prompt, will be in the s1 (filename) style. Which is why
the Style.apply method exists. This method takes a string and returns
the same string with escape sequences added before and after. The
before sequence switches to the style, while the after escape sequence
restores the terminal default style. This can be used like:
(gdb) python print(s1.apply("Filename Style"))
Now only the 'Filename Style' text will be styled. The next GDB
prompt will be in the default terminal style. Personally, I think the
apply method is the more useful, but having 'escape_sequence' matches
what gdb.Color offers, though if/when this patch is merged, I might
propose a similar 'apply' type method for the gdb.Color class.
The gdb.Style class has 'foreground', 'background', and 'intensity'
attributes which, when read, return the obvious values. These
attributes can also be written too.
When writing to an attribute of an unnamed Style object then the Style
object itself is updated, as you might expect.
When writing to an attribute of a named Style then the style setting
itself is updated as the following example shows:
(gdb) python s1 = gdb.Style("filename")
(gdb) python print(s1.foreground)
green
(gdb) show style filename foreground
The "filename" style foreground color is: green
(gdb) python s1.foreground=gdb.Color("red")
(gdb) python print(s1.foreground)
red
(gdb) show style filename foreground
The "filename" style foreground color is: red
(gdb)
We can see that a gdb.Style object is connected to the underlying
style settings, it doesn't take a copy of the style settings at
creation time. And the relationship works both ways. Continuing the
above example:
(gdb) set style filename foreground blue
(gdb) python print(s1.foreground)
blue
(gdb)
Here we see that changing the setting value causes the gdb.Style
object to update. And this is what you would want. I imagine this
being used in a Python extension to GDB, where a user might create
global objects for some named styles, and then use these globals to
format output from some custom commands. If a user of an extension
changes a style setting then the extension wants to adapt to that
change.
Both the Style.escape_sequence and Style.apply methods take the global
style enabled setting into consideration. If styling is disabled then
Style.escape_sequence will return an empty string, and Style.apply
will return an unmodified copy of the original string object (actually
the input object with Py_INCREF applied).
There is also support for representing a gdb.Style as a string:
(gdb) python s1 = gdb.Style("filename")
(gdb) python print(s1)
<gdb.Style name='filename', fg=green, bg=none, intensity=normal>
(gdb)
Unnamed styles are similar, but don't have a 'name' field.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
