[PATCH] gdb/python: Add gdb.InferiorThread.details attribute

[Andrew Burgess]

This adds a new read-only attribute gdb.InferiorThread.details, this
attribute contains a string, the results of target_extra_thread_info
for the thread, or None, if target_extra_thread_info returns nullptr.

As the string returned by target_extra_thread_info is unstructured,
this attribute is only really useful for echoing straight through to
the user, but, if a user wants to write a command that displays the
same, or a similar 'Thread Id' to the one seen in 'info threads', then
they need access to this string.

Given that the string produced by target_extra_thread_info varies by
target, there's only minimal testing of this attribute, I check that
the attribute can be accessed, and that the return value is either
None, or a string.
---
 gdb/NEWS                                  |  5 +++++
 gdb/doc/python.texi                       |  7 +++++++
 gdb/python/py-infthread.c                 | 21 +++++++++++++++++++++
 gdb/testsuite/gdb.python/py-infthread.exp |  5 +++++
 4 files changed, 38 insertions(+)

diff --git a/gdb/NEWS b/gdb/NEWS
index 9da74e71796..10b5489622c 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -185,6 +185,11 @@ GNU/Linux/LoongArch    loongarch*-*-linux*
      set styling').  When false, which is the default if the argument
      is not given, then no styling is applied to the returned string.
 
+  ** New read-only attribute gdb.InferiorThread.details, which is
+     either a string, containing additional, target specific thread
+     state information, or None, if there is no such additional
+     information.
+
 * 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 c1a3f5f2a7e..ac4ebbeaeae 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -3574,6 +3574,13 @@
 a @code{gdb.Inferior} object.  This attribute is not writable.
 @end defvar
 
+@defvar InferiorThread.details
+A string containing target specific, thread state information.  The
+format of this string varies by target.  If there is no additional
+state information for this thread, then this attribute contains
+@code{None}.
+@end defvar
+
 A @code{gdb.InferiorThread} object has the following methods:
 
 @defun InferiorThread.is_valid ()
diff --git a/gdb/python/py-infthread.c b/gdb/python/py-infthread.c
index e568d8d916e..efd536688c1 100644
--- a/gdb/python/py-infthread.c
+++ b/gdb/python/py-infthread.c
@@ -76,6 +76,24 @@ thpy_get_name (PyObject *self, void *ignore)
   return PyString_FromString (name);
 }
 
+/* Return a string containing target specific additional information about
+   the state of the thread, or None, if there is no such additional
+   information.  */
+
+static PyObject *
+thpy_get_details (PyObject *self, void *ignore)
+{
+  thread_object *thread_obj = (thread_object *) self;
+
+  THPY_REQUIRE_VALID (thread_obj);
+
+  const char *extra_info = target_extra_thread_info (thread_obj->thread);
+  if (extra_info == nullptr)
+    Py_RETURN_NONE;
+
+  return PyString_FromString (extra_info);
+}
+
 static int
 thpy_set_name (PyObject *self, PyObject *newvalue, void *ignore)
 {
@@ -347,6 +365,9 @@ static gdb_PyGetSetDef thread_object_getset[] =
 {
   { "name", thpy_get_name, thpy_set_name,
     "The name of the thread, as set by the user or the OS.", NULL },
+  { "details", thpy_get_details, NULL,
+    "A target specific string containing extra thread state details.",
+    NULL },
   { "num", thpy_get_num, NULL,
     "Per-inferior number of the thread, as assigned by GDB.", NULL },
   { "global_num", thpy_get_global_num, NULL,
diff --git a/gdb/testsuite/gdb.python/py-infthread.exp b/gdb/testsuite/gdb.python/py-infthread.exp
index 5cbbe43c44c..a7754198e60 100644
--- a/gdb/testsuite/gdb.python/py-infthread.exp
+++ b/gdb/testsuite/gdb.python/py-infthread.exp
@@ -77,6 +77,11 @@ gdb_py_test_silent_cmd "python gdb.selected_thread().name = None" \
 gdb_test "python print (gdb.selected_thread().name == name)" "True" \
     "check name of current thread again"
 
+gdb_test_no_output "python details = gdb.selected_thread().details" \
+    "record the thread details string"
+gdb_test "python print(details is None or isinstance(details, str))" "True" \
+    "check that the details has an acceptable type"
+
 gdb_test "python print ('result = %s' % t0.is_stopped ())" " = True" "test InferiorThread.is_stopped"
 gdb_test "python print ('result = %s' % t0.is_running ())" " = False" "test InferiorThread.is_running"
 gdb_test "python print ('result = %s' % t0.is_exited ())" " = False" "test InferiorThread.is_exited"
-- 
2.25.4