1//===-- ThreadPlanShouldStopHere.h ------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLDB_TARGET_THREADPLANSHOULDSTOPHERE_H
10#define LLDB_TARGET_THREADPLANSHOULDSTOPHERE_H
11
12#include "lldb/Target/ThreadPlan.h"
13
14namespace lldb_private {
15
16// This is an interface that ThreadPlans can adopt to allow flexible
17// modifications of the behavior when a thread plan comes to a place where it
18// would ordinarily stop. If such modification makes sense for your plan,
19// inherit from this class, and when you would be about to stop (in your
20// ShouldStop method), call InvokeShouldStopHereCallback, passing in the frame
21// comparison between where the step operation started and where you arrived.
22// If it returns true, then QueueStepOutFromHere will queue the plan to execute
23// instead of stopping.
24//
25// The classic example of the use of this is ThreadPlanStepInRange not stopping
26// in frames that have no debug information.
27//
28// This class also defines a set of flags to control general aspects of this
29// "ShouldStop" behavior.
30// A class implementing this protocol needs to define a default set of flags,
31// and can provide access to
32// changing that default flag set if it wishes.
33
34class ThreadPlanShouldStopHere {
35public:
36 struct ThreadPlanShouldStopHereCallbacks {
37 ThreadPlanShouldStopHereCallbacks() {
38 should_stop_here_callback = nullptr;
39 step_from_here_callback = nullptr;
40 }
41
42 ThreadPlanShouldStopHereCallbacks(
43 ThreadPlanShouldStopHereCallback should_stop,
44 ThreadPlanStepFromHereCallback step_from_here) {
45 should_stop_here_callback = should_stop;
46 step_from_here_callback = step_from_here;
47 }
48
49 void Clear() {
50 should_stop_here_callback = nullptr;
51 step_from_here_callback = nullptr;
52 }
53
54 ThreadPlanShouldStopHereCallback should_stop_here_callback;
55 ThreadPlanStepFromHereCallback step_from_here_callback;
56 };
57
58 enum {
59 eNone = 0,
60 eAvoidInlines = (1 << 0),
61 eStepInAvoidNoDebug = (1 << 1),
62 eStepOutAvoidNoDebug = (1 << 2)
63 };
64
65 // Constructors and Destructors
66 ThreadPlanShouldStopHere(ThreadPlan *owner);
67
68 ThreadPlanShouldStopHere(ThreadPlan *owner,
69 const ThreadPlanShouldStopHereCallbacks *callbacks,
70 void *baton = nullptr);
71 virtual ~ThreadPlanShouldStopHere();
72
73 // Set the ShouldStopHere callbacks. Pass in null to clear them and have no
74 // special behavior (though you can also call ClearShouldStopHereCallbacks
75 // for that purpose. If you pass in a valid pointer, it will adopt the non-
76 // null fields, and any null fields will be set to the default values.
77
78 void
79 SetShouldStopHereCallbacks(const ThreadPlanShouldStopHereCallbacks *callbacks,
80 void *baton) {
81 if (callbacks) {
82 m_callbacks = *callbacks;
83 if (!m_callbacks.should_stop_here_callback)
84 m_callbacks.should_stop_here_callback =
85 ThreadPlanShouldStopHere::DefaultShouldStopHereCallback;
86 if (!m_callbacks.step_from_here_callback)
87 m_callbacks.step_from_here_callback =
88 ThreadPlanShouldStopHere::DefaultStepFromHereCallback;
89 } else {
90 ClearShouldStopHereCallbacks();
91 }
92 m_baton = baton;
93 }
94
95 void ClearShouldStopHereCallbacks() { m_callbacks.Clear(); }
96
97 bool InvokeShouldStopHereCallback(lldb::FrameComparison operation,
98 Status &status);
99
100 lldb::ThreadPlanSP
101 CheckShouldStopHereAndQueueStepOut(lldb::FrameComparison operation,
102 Status &status);
103
104 lldb_private::Flags &GetFlags() { return m_flags; }
105
106 const lldb_private::Flags &GetFlags() const { return m_flags; }
107
108protected:
109 static bool DefaultShouldStopHereCallback(ThreadPlan *current_plan,
110 Flags &flags,
111 lldb::FrameComparison operation,
112 Status &status, void *baton);
113
114 static lldb::ThreadPlanSP
115 DefaultStepFromHereCallback(ThreadPlan *current_plan, Flags &flags,
116 lldb::FrameComparison operation, Status &status,
117 void *baton);
118
119 virtual lldb::ThreadPlanSP
120 QueueStepOutFromHerePlan(Flags &flags, lldb::FrameComparison operation,
121 Status &status);
122
123 // Implement this, and call it in the plan's constructor to set the default
124 // flags.
125 virtual void SetFlagsToDefault() = 0;
126
127 ThreadPlanShouldStopHereCallbacks m_callbacks;
128 void *m_baton;
129 ThreadPlan *m_owner;
130 lldb_private::Flags m_flags;
131
132private:
133 ThreadPlanShouldStopHere(const ThreadPlanShouldStopHere &) = delete;
134 const ThreadPlanShouldStopHere &
135 operator=(const ThreadPlanShouldStopHere &) = delete;
136};
137
138} // namespace lldb_private
139
140#endif // LLDB_TARGET_THREADPLANSHOULDSTOPHERE_H
141

source code of lldb/include/lldb/Target/ThreadPlanShouldStopHere.h