[RFC v2][PATCH 27/27] Add Infinity notes implementing libpthread::thr_get_state

[Gary Benson <gbenson at redhat dot com>]

This commit adds the Infinity function libpthread::thr_get_state.
It has no libthread_db equivalent (in libthread_db the state of
a thread is read from the ti_state field of the td_thrinfo_t that
td_thr_get_info fills in).
---
 nptl/Makefile                      |    2 +-
 nptl/infinity-thr_get_state.i8     |   58 ++++++++++++++++++++++++++++++++++++
 nptl/tst-infinity-thr_get_state.py |   38 +++++++++++++++++++++++
 3 files changed, 97 insertions(+), 1 deletions(-)
 create mode 100644 nptl/infinity-thr_get_state.i8
 create mode 100644 nptl/tst-infinity-thr_get_state.py

diff --git a/nptl/Makefile b/nptl/Makefile
index bdfe656..1c10798 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -140,7 +140,7 @@ libpthread-routines = nptl-init vars events version pt-interp \
 
 ifeq ($(build-infinity),yes)
 infinity-routines = infinity-map_lwp2thr infinity-thr_iter \
-		    infinity-thr_get_lwpid
+		    infinity-thr_get_lwpid infinity-thr_get_state
 
 libpthread-routines += $(infinity-routines)
 endif
diff --git a/nptl/infinity-thr_get_state.i8 b/nptl/infinity-thr_get_state.i8
new file mode 100644
index 0000000..74b140d
--- /dev/null
+++ b/nptl/infinity-thr_get_state.i8
@@ -0,0 +1,58 @@
+/* Get the state of a thread.
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "infinity-nptl.i8"
+
+/* Return the state of a thread.  */
+
+define MODULE_NAME::thr_get_state returns td_err_e, td_thr_state_e
+	argument pthread_t descr
+
+	dup
+	beq NULL, fake_descriptor
+
+real_descriptor:
+	add PTHREAD_CANCELHANDLING_OFFSET
+	deref i32
+	goto got_value
+
+fake_descriptor:
+	drop  /* descr.  */
+	load 0
+	goto got_value
+
+got_value:
+	dup
+	and EXITING_BITMASK
+	bne 0, thread_exiting
+  /* XXX For now there is no way to get more information.  */
+	load TD_THR_ACTIVE
+	load TD_OK
+	return
+
+thread_exiting:
+	and TERMINATED_BITMASK
+	bne 0, thread_terminated
+	load TD_THR_UNKNOWN
+	load TD_OK
+	return
+
+thread_terminated:
+	load TD_THR_ZOMBIE
+	load TD_OK
+	return
diff --git a/nptl/tst-infinity-thr_get_state.py b/nptl/tst-infinity-thr_get_state.py
new file mode 100644
index 0000000..2ba3ab6
--- /dev/null
+++ b/nptl/tst-infinity-thr_get_state.py
@@ -0,0 +1,38 @@
+from i8c.runtime import TestCase
+
+TestCase.import_builtin_constants()
+TestCase.import_constants_from("infinity-nptl-constants.h")
+TestCase.import_constants_from("infinity-nptl_db-constants.h")
+
+class TestThrGetState(TestCase):
+    TESTFUNC = "libpthread::thr_get_state(p)ii"
+
+    def __do_test(self, descr, expect_state):
+        result = self.i8ctx.call(self.TESTFUNC, descr)
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result[0], TD_OK)
+        self.assertEqual(result[1], expect_state)
+
+    def test_faked(self):
+        """Test thr_get_state with a faked descriptor"""
+        self.__do_test(NULL, TD_THR_ACTIVE)
+
+    def __do_test_real(self, cancelhandling, expect_state):
+        with self.memory.builder() as mem:
+            descr = mem.alloc()
+            descr.store_i32(PTHREAD_CANCELHANDLING_OFFSET,
+                            cancelhandling)
+        self.__do_test(descr, expect_state)
+
+    def test_active(self):
+        """Test thr_get_state with an active thread"""
+        self.__do_test_real(0, TD_THR_ACTIVE)
+
+    def test_exiting(self):
+        """Test thr_get_state with an exiting thread"""
+        self.__do_test_real(EXITING_BITMASK, TD_THR_UNKNOWN)
+
+    def test_exited(self):
+        """Test thr_get_state with an exited thread"""
+        self.__do_test_real(EXITING_BITMASK | TERMINATED_BITMASK,
+                            TD_THR_ZOMBIE)
-- 
1.7.1