Export the watchpoint related API (SBWatchpointLocation class and added SBTarget methods)

to the Python interface.

Implement yet another (threre're 3 now) iterator protocol for SBTarget: watchpoint_location_iter(),
to iterate on the available watchpoint locations.  And add a print representation for
SBWatchpointLocation.

Exercise some of these Python API with TestWatchpointLocationIter.py.

llvm-svn: 140595

lldb/test/python_api/watchpoint/TestWatchpointLocationIter.py

@@ -0,0 +1,118 @@
+"""
+Use lldb Python SBTarget API to iterate on the watchpoint(s) for the target.
+"""
+
+import os, time
+import re
+import unittest2
+import lldb, lldbutil
+from lldbtest import *
+
+class WatchpointLocationIteratorTestCase(TestBase):
+
+    mydir = os.path.join("python_api", "watchpoint")
+
+    def setUp(self):
+        # Call super's setUp().
+        TestBase.setUp(self)
+        # Our simple source filename.
+        self.source = 'main.c'
+        # Find the line number to break inside main().
+        self.line = line_number(self.source, '// Set break point at this line.')
+
+    @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
+    @python_api_test
+    def test_watch_loc_iter_with_dsym(self):
+        """Exercise SBTarget.watchpoint_location_iter() API to iterate on the available watchpoint locations."""
+        self.buildDsym()
+        self.do_watchpoint_location_iter()
+
+    @python_api_test
+    def test_watch_loc_iter_with_dwarf(self):
+        """Exercise SBTarget.watchpoint_location_iter() API to iterate on the available watchpoint locations."""
+        self.buildDwarf()
+        self.do_watchpoint_location_iter()
+
+    def do_watchpoint_location_iter(self):
+        """Use SBTarget.watchpoint_location_iter() to do Pythonic iteration on the available watchpoint locations."""
+        exe = os.path.join(os.getcwd(), "a.out")
+
+        # Create a target by the debugger.
+        target = self.dbg.CreateTarget(exe)
+        self.assertTrue(target, VALID_TARGET)
+
+        # Create a breakpoint on main.c in order to set our watchpoint later.
+        breakpoint = target.BreakpointCreateByLocation(self.source, self.line)
+        self.assertTrue(breakpoint and
+                        breakpoint.GetNumLocations() == 1,
+                        VALID_BREAKPOINT)
+
+        # Now launch the process, and do not stop at the entry point.
+        process = target.LaunchSimple(None, None, os.getcwd())
+
+        # We should be stopped due to the breakpoint.  Get frame #0.
+        process = target.GetProcess()
+        self.assertTrue(process.GetState() == lldb.eStateStopped,
+                        PROCESS_STOPPED)
+        thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
+        frame0 = thread.GetFrameAtIndex(0)
+
+        value = frame0.WatchValue('global',
+                                  lldb.eValueTypeVariableGlobal,
+                                  lldb.LLDB_WATCH_TYPE_READ|lldb.LLDB_WATCH_TYPE_WRITE)
+        self.assertTrue(value, "Successfully found the variable and set a watchpoint")
+        self.DebugSBValue(value)
+
+        # There should be only 1 watchpoint location under the target.
+        self.assertTrue(target.GetNumWatchpointLocations() == 1)
+        wp_loc = target.GetWatchpointLocationAtIndex(0) 
+        self.assertTrue(wp_loc.IsEnabled())
+        watch_id = wp_loc.GetID()
+        self.assertTrue(watch_id != 0)
+
+        # Continue.  Expect the program to stop due to the variable being written to.
+        process.Continue()
+
+        # Hide stdout if not running with '-t' option.
+        if not self.TraceOn():
+            self.HideStdout()
+
+        # Print the stack traces.
+        lldbutil.print_stacktraces(process)
+
+        thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonWatchpoint)
+        self.assertTrue(thread, "The thread stopped due to watchpoint")
+        self.DebugSBValue(value)
+
+        # We currently only support hardware watchpoint.  Verify that we have a
+        # meaningful hardware index at this point.  Exercise the printed repr of
+        # SBWatchpointLocation.
+        print wp_loc
+        self.assertTrue(wp_loc.GetHardwareIndex() != -1)
+
+        # Now disable the 'rw' watchpoint.  The program won't stop when it reads
+        # 'global' next.
+        wp_loc.SetEnabled(False)
+        self.assertTrue(wp_loc.GetHardwareIndex() == -1)
+        self.assertFalse(wp_loc.IsEnabled())
+
+        # Continue.  The program does not stop again when the variable is being
+        # read from because the watchpoint location has been disabled.
+        process.Continue()
+
+        # At this point, the inferior process should have exited.
+        self.assertTrue(process.GetState() == lldb.eStateExited, PROCESS_EXITED)
+
+        # Verify some vital statistics and exercise the iterator API.
+        for wp_loc in target.watchpoint_location_iter():
+            self.assertTrue(wp_loc)
+            self.assertTrue(wp_loc.GetWatchSize() == 4)
+            self.assertTrue(wp_loc.GetHitCount() == 1)
+            print wp_loc
+
+
+if __name__ == '__main__':
+    import atexit
+    lldb.SBDebugger.Initialize()
+    atexit.register(lambda: lldb.SBDebugger.Terminate())
+    unittest2.main()