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      1 """
      2 Use lldb Python SBtarget.WatchAddress() API to create a watchpoint for write of '*g_char_ptr'.
      3 """
      4 
      5 import os, time
      6 import re
      7 import unittest2
      8 import lldb, lldbutil
      9 from lldbtest import *
     10 
     11 class TargetWatchAddressAPITestCase(TestBase):
     12 
     13     mydir = os.path.join("python_api", "watchpoint", "watchlocation")
     14 
     15     def setUp(self):
     16         # Call super's setUp().
     17         TestBase.setUp(self)
     18         # Our simple source filename.
     19         self.source = 'main.cpp'
     20         # Find the line number to break inside main().
     21         self.line = line_number(self.source, '// Set break point at this line.')
     22         # This is for verifying that watch location works.
     23         self.violating_func = "do_bad_thing_with_location";
     24 
     25     @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
     26     @python_api_test
     27     @dsym_test
     28     def test_watch_address_with_dsym(self):
     29         """Exercise SBTarget.WatchAddress() API to set a watchpoint."""
     30         self.buildDsym()
     31         self.do_set_watchaddress()
     32 
     33     @expectedFailureFreeBSD('llvm.org/pr16706') # Watchpoints fail on FreeBSD
     34     @skipIfLinux # llvm.org/pr14323 - skip due to incomplete multi-threaded debug support
     35     @python_api_test
     36     @dwarf_test
     37     def test_watch_address_with_dwarf(self):
     38         """Exercise SBTarget.WatchAddress() API to set a watchpoint."""
     39         self.buildDwarf()
     40         self.do_set_watchaddress()
     41 
     42     @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
     43     @python_api_test
     44     @dsym_test
     45     def test_watch_address_with_invalid_watch_size_with_dsym(self):
     46         """Exercise SBTarget.WatchAddress() API but pass an invalid watch_size."""
     47         self.buildDsym()
     48         self.do_set_watchaddress_with_invalid_watch_size()
     49 
     50     @python_api_test
     51     @dwarf_test
     52     def test_watch_address_with_invalid_watch_size_with_dwarf(self):
     53         """Exercise SBTarget.WatchAddress() API but pass an invalid watch_size."""
     54         self.buildDwarf()
     55         self.do_set_watchaddress_with_invalid_watch_size()
     56 
     57     def do_set_watchaddress(self):
     58         """Use SBTarget.WatchAddress() to set a watchpoint and verify that the program stops later due to the watchpoint."""
     59         exe = os.path.join(os.getcwd(), "a.out")
     60 
     61         # Create a target by the debugger.
     62         target = self.dbg.CreateTarget(exe)
     63         self.assertTrue(target, VALID_TARGET)
     64 
     65         # Now create a breakpoint on main.c.
     66         breakpoint = target.BreakpointCreateByLocation(self.source, self.line)
     67         self.assertTrue(breakpoint and
     68                         breakpoint.GetNumLocations() == 1,
     69                         VALID_BREAKPOINT)
     70 
     71         # Now launch the process, and do not stop at the entry point.
     72         process = target.LaunchSimple(None, None, os.getcwd())
     73 
     74         # We should be stopped due to the breakpoint.  Get frame #0.
     75         process = target.GetProcess()
     76         self.assertTrue(process.GetState() == lldb.eStateStopped,
     77                         PROCESS_STOPPED)
     78         thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
     79         frame0 = thread.GetFrameAtIndex(0)
     80 
     81         value = frame0.FindValue('g_char_ptr',
     82                                  lldb.eValueTypeVariableGlobal)
     83         pointee = value.CreateValueFromAddress("pointee",
     84                                                value.GetValueAsUnsigned(0),
     85                                                value.GetType().GetPointeeType())
     86         # Watch for write to *g_char_ptr.
     87         error = lldb.SBError();
     88         watchpoint = target.WatchAddress(value.GetValueAsUnsigned(), 1, False, True, error)
     89         self.assertTrue(value and watchpoint,
     90                         "Successfully found the pointer and set a watchpoint")
     91         self.DebugSBValue(value)
     92         self.DebugSBValue(pointee)
     93 
     94         # Hide stdout if not running with '-t' option.
     95         if not self.TraceOn():
     96             self.HideStdout()
     97 
     98         print watchpoint
     99 
    100         # Continue.  Expect the program to stop due to the variable being written to.
    101         process.Continue()
    102 
    103         if (self.TraceOn()):
    104             lldbutil.print_stacktraces(process)
    105 
    106         thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonWatchpoint)
    107         self.assertTrue(thread, "The thread stopped due to watchpoint")
    108         self.DebugSBValue(value)
    109         self.DebugSBValue(pointee)
    110 
    111         self.expect(lldbutil.print_stacktrace(thread, string_buffer=True), exe=False,
    112             substrs = [self.violating_func])
    113 
    114         # This finishes our test.
    115 
    116     def do_set_watchaddress_with_invalid_watch_size(self):
    117         """Use SBTarget.WatchAddress() to set a watchpoint with invalid watch_size and verify we get a meaningful error message."""
    118         exe = os.path.join(os.getcwd(), "a.out")
    119 
    120         # Create a target by the debugger.
    121         target = self.dbg.CreateTarget(exe)
    122         self.assertTrue(target, VALID_TARGET)
    123 
    124         # Now create a breakpoint on main.c.
    125         breakpoint = target.BreakpointCreateByLocation(self.source, self.line)
    126         self.assertTrue(breakpoint and
    127                         breakpoint.GetNumLocations() == 1,
    128                         VALID_BREAKPOINT)
    129 
    130         # Now launch the process, and do not stop at the entry point.
    131         process = target.LaunchSimple(None, None, os.getcwd())
    132 
    133         # We should be stopped due to the breakpoint.  Get frame #0.
    134         process = target.GetProcess()
    135         self.assertTrue(process.GetState() == lldb.eStateStopped,
    136                         PROCESS_STOPPED)
    137         thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
    138         frame0 = thread.GetFrameAtIndex(0)
    139 
    140         value = frame0.FindValue('g_char_ptr',
    141                                  lldb.eValueTypeVariableGlobal)
    142         pointee = value.CreateValueFromAddress("pointee",
    143                                                value.GetValueAsUnsigned(0),
    144                                                value.GetType().GetPointeeType())
    145         # Watch for write to *g_char_ptr.
    146         error = lldb.SBError();
    147         watchpoint = target.WatchAddress(value.GetValueAsUnsigned(), 365, False, True, error)
    148         self.assertFalse(watchpoint)
    149         self.expect(error.GetCString(), exe=False,
    150             substrs = ['watch size of %d is not supported' % 365])
    151 
    152 
    153 if __name__ == '__main__':
    154     import atexit
    155     lldb.SBDebugger.Initialize()
    156     atexit.register(lambda: lldb.SBDebugger.Terminate())
    157     unittest2.main()
    158