1// LLDB C++ API Test: Verify that when the Debugger stdin
2// is set to a FILE *, lldb can still successfully run a
3// python command in a stop hook.
4
5#include <errno.h>
6#include <mutex>
7#include <stdio.h>
8#include <string>
9#include <vector>
10
11%include_SB_APIs%
12
13#include "common.h"
14
15using namespace lldb;
16
17void test(SBDebugger &dbg, std::vector<std::string> args) {
18  // The problem we had was that when the thread that was
19  // waiting on input went into the call to 'read' it had
20  // the file handle lock.  Then when the python interpreter
21  // Initialized itself to run the python command, it tried
22  // to flush the file channel, and that deadlocked.
23  // This only happens when Async is true, since otherwise
24  // the process event is handled on the I/O read thread,
25  // which sidestepped the problem.
26  dbg.SetAsync(true);
27
28  SBTarget target = dbg.CreateTarget(args.at(0).c_str());
29  if (!target.IsValid())
30    throw Exception("invalid target");
31
32  SBBreakpoint breakpoint = target.BreakpointCreateByName("next");
33  if (!breakpoint.IsValid())
34    throw Exception("invalid breakpoint");
35
36  SBCommandInterpreter interp = dbg.GetCommandInterpreter();
37  SBCommandReturnObject result;
38
39  // Bring in the python command. We actually add two commands,
40  // one that runs in the stop hook and sets a variable when it
41  // runs, and one that reports out the variable so we can ensure
42  // that we did indeed run the stop hook.
43  const char *source_dir = "%SOURCE_DIR%";
44  SBFileSpec script_spec(source_dir);
45  script_spec.AppendPathComponent("some_cmd.py");
46  char path[PATH_MAX];
47  script_spec.GetPath(path, PATH_MAX);
48
49  std::string import_command("command script import ");
50  import_command.append(path);
51  interp.HandleCommand(import_command.c_str(), result);
52  if (!result.Succeeded())
53    throw Exception("Couldn't import %SOURCE_DIR%/some_cmd.py");
54
55  SBProcess process = target.LaunchSimple(nullptr, nullptr, nullptr);
56  if (!process.IsValid())
57    throw Exception("Couldn't launch process.");
58  if (process.GetState() != lldb::eStateStopped)
59    throw Exception("Process was not stopped");
60
61  process.SetSelectedThreadByIndexID(0);
62
63  // Now add the stop hook:
64  interp.HandleCommand("target stop-hook add -o some-cmd", result);
65  if (!result.Succeeded())
66    throw Exception("Couldn't add a stop hook.");
67
68  // Now switch the I/O over to a pipe, which will be handled by the
69  // NativeFile class:
70  int to_lldb_des[2];
71  int pipe_result = pipe(to_lldb_des);
72  FILE *fh_lldb_in = fdopen(to_lldb_des[0], "r");
73  FILE *fh_to_lldb = fdopen(to_lldb_des[1], "w");
74
75  // We need to reset the handle before destroying the debugger
76  // or the same deadlock will stall exiting:
77  class Cleanup {
78  public:
79    Cleanup(SBDebugger dbg, int filedes[2]) : m_dbg(dbg) {
80      m_file = m_dbg.GetInputFileHandle();
81      m_filedes[0] = filedes[0];
82      m_filedes[1] = filedes[1];
83    }
84    ~Cleanup() {
85      m_dbg.SetInputFileHandle(m_file, false);
86      close(m_filedes[0]);
87      close(m_filedes[1]);
88    }
89
90  private:
91    FILE *m_file;
92    SBDebugger m_dbg;
93    int m_filedes[2];
94  };
95  Cleanup cleanup(dbg, to_lldb_des);
96
97  dbg.SetInputFileHandle(fh_lldb_in, false);
98
99  // Now run the command interpreter.  You have to pass true to
100  // start thread so we will run the I/O in a separate thread.
101  dbg.RunCommandInterpreter(false, true);
102
103  // Now issue a stepi, and fetch the running and stopped events:
104  fprintf(fh_to_lldb, "thread step-inst\n");
105
106  SBEvent proc_event;
107  StateType state;
108  bool got_event;
109
110  got_event = dbg.GetListener().WaitForEventForBroadcaster(
111      100, process.GetBroadcaster(), proc_event);
112  if (!got_event)
113    throw Exception("Didn't get running event");
114  state = SBProcess::GetStateFromEvent(proc_event);
115  if (state != eStateRunning)
116    throw Exception("Event wasn't a running event.");
117
118  got_event = dbg.GetListener().WaitForEventForBroadcaster(
119      100, process.GetBroadcaster(), proc_event);
120  if (!got_event)
121    throw Exception("Didn't get a stopped event");
122  state = SBProcess::GetStateFromEvent(proc_event);
123  if (state != eStateStopped)
124    throw Exception("Event wasn't a stop event.");
125
126  // At this point the stop hook should have run.  Check that:
127  interp.HandleCommand("report-cmd", result);
128  if (!result.Succeeded())
129    throw Exception("Didn't actually call stop hook.");
130}
131