xref: /llvm-project/lldb/test/API/functionalities/conditional_break/TestConditionalBreak.py (revision 47c4c6a7469f3fd3e364a9b3669838686d4f1de6) 
1"""
2Test conditionally break on a function and inspect its variables.
3"""
4
5from __future__ import print_function
6
7
8import lldb
9from lldbsuite.test.decorators import *
10from lldbsuite.test.lldbtest import *
11from lldbsuite.test import lldbutil
12
13# rdar://problem/8532131
14# lldb not able to digest the clang-generated debug info correctly with respect to function name
15#
16# This class currently fails for clang as well as llvm-gcc.
17
18
19class ConditionalBreakTestCase(TestBase):
20
21    mydir = TestBase.compute_mydir(__file__)
22
23    @add_test_categories(['pyapi'])
24    def test_with_python(self):
25        """Exercise some thread and frame APIs to break if c() is called by a()."""
26        self.build()
27        self.do_conditional_break()
28
29    def test_with_command(self):
30        """Simulate a user using lldb commands to break on c() if called from a()."""
31        self.build()
32        self.simulate_conditional_break_by_user()
33
34    def do_conditional_break(self):
35        """Exercise some thread and frame APIs to break if c() is called by a()."""
36        exe = self.getBuildArtifact("a.out")
37
38        target = self.dbg.CreateTarget(exe)
39        self.assertTrue(target, VALID_TARGET)
40
41        breakpoint = target.BreakpointCreateByName("c", exe)
42        self.assertTrue(breakpoint, VALID_BREAKPOINT)
43
44        # Now launch the process, and do not stop at entry point.
45        process = target.LaunchSimple(
46            None, None, self.get_process_working_directory())
47
48        self.assertTrue(process, PROCESS_IS_VALID)
49
50        # The stop reason of the thread should be breakpoint.
51        self.assertState(process.GetState(), lldb.eStateStopped,
52                         STOPPED_DUE_TO_BREAKPOINT)
53
54        # Find the line number where a's parent frame function is c.
55        line = line_number(
56            'main.c',
57            "// Find the line number where c's parent frame is a here.")
58
59        # Suppose we are only interested in the call scenario where c()'s
60        # immediate caller is a() and we want to find out the value passed from
61        # a().
62        #
63        # The 10 in range(10) is just an arbitrary number, which means we would
64        # like to try for at most 10 times.
65        for j in range(10):
66            if self.TraceOn():
67                print("j is: ", j)
68            thread = lldbutil.get_one_thread_stopped_at_breakpoint(
69                process, breakpoint)
70            self.assertIsNotNone(
71                thread, "Expected one thread to be stopped at the breakpoint")
72
73            if thread.GetNumFrames() >= 2:
74                frame0 = thread.GetFrameAtIndex(0)
75                name0 = frame0.GetFunction().GetName()
76                frame1 = thread.GetFrameAtIndex(1)
77                name1 = frame1.GetFunction().GetName()
78                # lldbutil.print_stacktrace(thread)
79                self.assertEqual(name0, "c", "Break on function c()")
80                if (name1 == "a"):
81                    # By design, we know that a() calls c() only from main.c:27.
82                    # In reality, similar logic can be used to find out the call
83                    # site.
84                    self.assertEqual(frame1.GetLineEntry().GetLine(), line,
85                                    "Immediate caller a() at main.c:%d" % line)
86
87                    # And the local variable 'val' should have a value of (int)
88                    # 3.
89                    val = frame1.FindVariable("val")
90                    self.assertEqual("int", val.GetTypeName())
91                    self.assertEqual("3", val.GetValue())
92                    break
93
94            process.Continue()
95
96    def simulate_conditional_break_by_user(self):
97        """Simulate a user using lldb commands to break on c() if called from a()."""
98
99        # Sourcing .lldb in the current working directory, which sets the main
100        # executable, sets the breakpoint on c(), and adds the callback for the
101        # breakpoint such that lldb only stops when the caller of c() is a().
102        # the "my" package that defines the date() function.
103        if self.TraceOn():
104            print("About to source .lldb")
105
106        if not self.TraceOn():
107            self.HideStdout()
108
109        # Separate out the "file " + self.getBuildArtifact("a.out") command from .lldb file, for the sake of
110        # remote testsuite.
111        self.runCmd("file " + self.getBuildArtifact("a.out"))
112        self.runCmd("command source .lldb")
113
114        self.runCmd("break list")
115
116        if self.TraceOn():
117            print("About to run.")
118        self.runCmd("run", RUN_SUCCEEDED)
119
120        self.runCmd("break list")
121
122        if self.TraceOn():
123            print("Done running")
124
125        # The stop reason of the thread should be breakpoint.
126        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
127                    substrs=['stopped', 'stop reason = breakpoint'])
128
129        # The frame info for frame #0 points to a.out`c and its immediate caller
130        # (frame #1) points to a.out`a.
131
132        self.expect("frame info", "We should stop at c()",
133                    substrs=["a.out`c"])
134
135        # Select our parent frame as the current frame.
136        self.runCmd("frame select 1")
137        self.expect("frame info", "The immediate caller should be a()",
138                    substrs=["a.out`a"])
139