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      1 """
      2 Use lldb Python SBTarget API to iterate on the watchpoint(s) for the target.
      3 """
      4 
      5 import os, time
      6 import re
      7 import unittest2
      8 import lldb, lldbutil
      9 from lldbtest import *
     10 
     11 class WatchpointIteratorTestCase(TestBase):
     12 
     13     mydir = os.path.join("python_api", "watchpoint")
     14 
     15     def setUp(self):
     16         # Call super's setUp().
     17         TestBase.setUp(self)
     18         # Our simple source filename.
     19         self.source = 'main.c'
     20         # Find the line number to break inside main().
     21         self.line = line_number(self.source, '// Set break point at this line.')
     22 
     23     @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
     24     @python_api_test
     25     @dsym_test
     26     def test_watch_iter_with_dsym(self):
     27         """Exercise SBTarget.watchpoint_iter() API to iterate on the available watchpoints."""
     28         self.buildDsym()
     29         self.do_watchpoint_iter()
     30 
     31     @expectedFailureFreeBSD('llvm.org/pr16706') # Watchpoints fail on FreeBSD
     32     @python_api_test
     33     @dwarf_test
     34     def test_watch_iter_with_dwarf(self):
     35         """Exercise SBTarget.watchpoint_iter() API to iterate on the available watchpoints."""
     36         self.buildDwarf()
     37         self.do_watchpoint_iter()
     38 
     39     def do_watchpoint_iter(self):
     40         """Use SBTarget.watchpoint_iter() to do Pythonic iteration on the available watchpoints."""
     41         exe = os.path.join(os.getcwd(), "a.out")
     42 
     43         # Create a target by the debugger.
     44         target = self.dbg.CreateTarget(exe)
     45         self.assertTrue(target, VALID_TARGET)
     46 
     47         # Create a breakpoint on main.c in order to set our watchpoint later.
     48         breakpoint = target.BreakpointCreateByLocation(self.source, self.line)
     49         self.assertTrue(breakpoint and
     50                         breakpoint.GetNumLocations() == 1,
     51                         VALID_BREAKPOINT)
     52 
     53         # Now launch the process, and do not stop at the entry point.
     54         process = target.LaunchSimple(None, None, os.getcwd())
     55 
     56         # We should be stopped due to the breakpoint.  Get frame #0.
     57         process = target.GetProcess()
     58         self.assertTrue(process.GetState() == lldb.eStateStopped,
     59                         PROCESS_STOPPED)
     60         thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
     61         frame0 = thread.GetFrameAtIndex(0)
     62 
     63         # Watch 'global' for read and write.
     64         value = frame0.FindValue('global', lldb.eValueTypeVariableGlobal)
     65         error = lldb.SBError();
     66         watchpoint = value.Watch(True, True, True, error)
     67         self.assertTrue(value and watchpoint,
     68                         "Successfully found the variable and set a watchpoint")
     69         self.DebugSBValue(value)
     70 
     71         # Hide stdout if not running with '-t' option.
     72         if not self.TraceOn():
     73             self.HideStdout()
     74 
     75         # There should be only 1 watchpoint location under the target.
     76         self.assertTrue(target.GetNumWatchpoints() == 1)
     77         self.assertTrue(watchpoint.IsEnabled())
     78         watch_id = watchpoint.GetID()
     79         self.assertTrue(watch_id != 0)
     80 
     81         # Continue.  Expect the program to stop due to the variable being written to.
     82         process.Continue()
     83 
     84         # Hide stdout if not running with '-t' option.
     85         if not self.TraceOn():
     86             self.HideStdout()
     87 
     88         # Print the stack traces.
     89         lldbutil.print_stacktraces(process)
     90 
     91         thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonWatchpoint)
     92         self.assertTrue(thread, "The thread stopped due to watchpoint")
     93         self.DebugSBValue(value)
     94 
     95         # We currently only support hardware watchpoint.  Verify that we have a
     96         # meaningful hardware index at this point.  Exercise the printed repr of
     97         # SBWatchpointLocation.
     98         print watchpoint
     99         self.assertTrue(watchpoint.GetHardwareIndex() != -1)
    100 
    101         # SBWatchpoint.GetDescription() takes a description level arg.
    102         print lldbutil.get_description(watchpoint, lldb.eDescriptionLevelFull)
    103 
    104         # Now disable the 'rw' watchpoint.  The program won't stop when it reads
    105         # 'global' next.
    106         watchpoint.SetEnabled(False)
    107         self.assertTrue(watchpoint.GetHardwareIndex() == -1)
    108         self.assertFalse(watchpoint.IsEnabled())
    109 
    110         # Continue.  The program does not stop again when the variable is being
    111         # read from because the watchpoint location has been disabled.
    112         process.Continue()
    113 
    114         # At this point, the inferior process should have exited.
    115         self.assertTrue(process.GetState() == lldb.eStateExited, PROCESS_EXITED)
    116 
    117         # Verify some vital statistics and exercise the iterator API.
    118         for watchpoint in target.watchpoint_iter():
    119             self.assertTrue(watchpoint)
    120             self.assertTrue(watchpoint.GetWatchSize() == 4)
    121             self.assertTrue(watchpoint.GetHitCount() == 1)
    122             print watchpoint
    123 
    124 
    125 if __name__ == '__main__':
    126     import atexit
    127     lldb.SBDebugger.Initialize()
    128     atexit.register(lambda: lldb.SBDebugger.Terminate())
    129     unittest2.main()
    130