xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 22c55d180ddc9772ee03d5034677d27a2735c92e)
1 //===-- CommandObjectExpression.cpp -----------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "CommandObjectExpression.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Interpreter/Args.h"
17 #include "lldb/Core/Value.h"
18 #include "lldb/Core/InputReader.h"
19 #include "lldb/Core/ValueObjectVariable.h"
20 #include "lldb/Expression/ClangExpressionVariable.h"
21 #include "lldb/Expression/ClangUserExpression.h"
22 #include "lldb/Expression/ClangFunction.h"
23 #include "lldb/Expression/DWARFExpression.h"
24 #include "lldb/Host/Host.h"
25 #include "lldb/Core/Debugger.h"
26 #include "lldb/Interpreter/CommandInterpreter.h"
27 #include "lldb/Interpreter/CommandReturnObject.h"
28 #include "lldb/Target/ObjCLanguageRuntime.h"
29 #include "lldb/Symbol/ObjectFile.h"
30 #include "lldb/Symbol/Variable.h"
31 #include "lldb/Target/Process.h"
32 #include "lldb/Target/StackFrame.h"
33 #include "lldb/Target/Target.h"
34 #include "lldb/Target/Thread.h"
35 #include "llvm/ADT/StringRef.h"
36 
37 using namespace lldb;
38 using namespace lldb_private;
39 
40 CommandObjectExpression::CommandOptions::CommandOptions (CommandInterpreter &interpreter) :
41     Options(interpreter)
42 {
43     // Keep only one place to reset the values to their defaults
44     OptionParsingStarting();
45 }
46 
47 
48 CommandObjectExpression::CommandOptions::~CommandOptions ()
49 {
50 }
51 
52 Error
53 CommandObjectExpression::CommandOptions::SetOptionValue (uint32_t option_idx, const char *option_arg)
54 {
55     Error error;
56 
57     char short_option = (char) m_getopt_table[option_idx].val;
58 
59     switch (short_option)
60     {
61       //case 'l':
62       //if (language.SetLanguageFromCString (option_arg) == false)
63       //{
64       //    error.SetErrorStringWithFormat("Invalid language option argument '%s'.\n", option_arg);
65       //}
66       //break;
67 
68     case 'g':
69         debug = true;
70         break;
71 
72     case 'f':
73         error = Args::StringToFormat(option_arg, format, NULL);
74         break;
75 
76     case 'o':
77         print_object = true;
78         break;
79 
80     case 'd':
81         {
82             bool success;
83             bool result;
84             result = Args::StringToBoolean(option_arg, true, &success);
85             if (!success)
86                 error.SetErrorStringWithFormat("Invalid dynamic value setting: \"%s\".\n", option_arg);
87             else
88             {
89                 if (result)
90                     use_dynamic = eLazyBoolYes;
91                 else
92                     use_dynamic = eLazyBoolNo;
93             }
94         }
95         break;
96 
97     case 'u':
98         bool success;
99         unwind_on_error = Args::StringToBoolean(option_arg, true, &success);
100         if (!success)
101             error.SetErrorStringWithFormat("Could not convert \"%s\" to a boolean value.", option_arg);
102         break;
103 
104     default:
105         error.SetErrorStringWithFormat("Invalid short option character '%c'.\n", short_option);
106         break;
107     }
108 
109     return error;
110 }
111 
112 void
113 CommandObjectExpression::CommandOptions::OptionParsingStarting ()
114 {
115     //language.Clear();
116     debug = false;
117     format = eFormatDefault;
118     print_object = false;
119     use_dynamic = eLazyBoolCalculate;
120     unwind_on_error = true;
121     show_types = true;
122     show_summary = true;
123 }
124 
125 const OptionDefinition*
126 CommandObjectExpression::CommandOptions::GetDefinitions ()
127 {
128     return g_option_table;
129 }
130 
131 CommandObjectExpression::CommandObjectExpression (CommandInterpreter &interpreter) :
132     CommandObject (interpreter,
133                    "expression",
134                    "Evaluate a C/ObjC/C++ expression in the current program context, using variables currently in scope.",
135                    NULL),
136     m_options (interpreter),
137     m_expr_line_count (0),
138     m_expr_lines ()
139 {
140   SetHelpLong(
141 "Examples: \n\
142 \n\
143    expr my_struct->a = my_array[3] \n\
144    expr -f bin -- (index * 8) + 5 \n\
145    expr char c[] = \"foo\"; c[0]\n");
146 
147     CommandArgumentEntry arg;
148     CommandArgumentData expression_arg;
149 
150     // Define the first (and only) variant of this arg.
151     expression_arg.arg_type = eArgTypeExpression;
152     expression_arg.arg_repetition = eArgRepeatPlain;
153 
154     // There is only one variant this argument could be; put it into the argument entry.
155     arg.push_back (expression_arg);
156 
157     // Push the data for the first argument into the m_arguments vector.
158     m_arguments.push_back (arg);
159 }
160 
161 CommandObjectExpression::~CommandObjectExpression ()
162 {
163 }
164 
165 Options *
166 CommandObjectExpression::GetOptions ()
167 {
168     return &m_options;
169 }
170 
171 
172 bool
173 CommandObjectExpression::Execute
174 (
175     Args& command,
176     CommandReturnObject &result
177 )
178 {
179     return false;
180 }
181 
182 
183 size_t
184 CommandObjectExpression::MultiLineExpressionCallback
185 (
186     void *baton,
187     InputReader &reader,
188     lldb::InputReaderAction notification,
189     const char *bytes,
190     size_t bytes_len
191 )
192 {
193     CommandObjectExpression *cmd_object_expr = (CommandObjectExpression *) baton;
194     bool batch_mode = reader.GetDebugger().GetCommandInterpreter().GetBatchCommandMode();
195 
196     switch (notification)
197     {
198     case eInputReaderActivate:
199         if (!batch_mode)
200         {
201             StreamSP async_strm_sp(reader.GetDebugger().GetAsyncOutputStream());
202             if (async_strm_sp)
203             {
204                 async_strm_sp->PutCString("Enter expressions, then terminate with an empty line to evaluate:\n");
205                 async_strm_sp->Flush();
206             }
207         }
208         // Fall through
209     case eInputReaderReactivate:
210         break;
211 
212     case eInputReaderDeactivate:
213         break;
214 
215     case eInputReaderAsynchronousOutputWritten:
216         break;
217 
218     case eInputReaderGotToken:
219         ++cmd_object_expr->m_expr_line_count;
220         if (bytes && bytes_len)
221         {
222             cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
223         }
224 
225         if (bytes_len == 0)
226             reader.SetIsDone(true);
227         break;
228 
229     case eInputReaderInterrupt:
230         cmd_object_expr->m_expr_lines.clear();
231         reader.SetIsDone (true);
232         if (!batch_mode)
233         {
234             StreamSP async_strm_sp (reader.GetDebugger().GetAsyncOutputStream());
235             if (async_strm_sp)
236             {
237                 async_strm_sp->PutCString("Expression evaluation cancelled.\n");
238                 async_strm_sp->Flush();
239             }
240         }
241         break;
242 
243     case eInputReaderEndOfFile:
244         reader.SetIsDone (true);
245         break;
246 
247     case eInputReaderDone:
248 		if (cmd_object_expr->m_expr_lines.size() > 0)
249         {
250             StreamSP output_stream = reader.GetDebugger().GetAsyncOutputStream();
251             StreamSP error_stream = reader.GetDebugger().GetAsyncErrorStream();
252             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
253                                                  output_stream.get(),
254                                                  error_stream.get());
255             output_stream->Flush();
256             error_stream->Flush();
257         }
258         break;
259     }
260 
261     return bytes_len;
262 }
263 
264 bool
265 CommandObjectExpression::EvaluateExpression
266 (
267     const char *expr,
268     Stream *output_stream,
269     Stream *error_stream,
270     CommandReturnObject *result
271 )
272 {
273     if (m_exe_ctx.target)
274     {
275         lldb::ValueObjectSP result_valobj_sp;
276 
277         ExecutionResults exe_results;
278 
279         bool keep_in_memory = true;
280         lldb::DynamicValueType use_dynamic;
281         // If use dynamic is not set, get it from the target:
282         switch (m_options.use_dynamic)
283         {
284         case eLazyBoolCalculate:
285             use_dynamic = m_exe_ctx.target->GetPreferDynamicValue();
286             break;
287         case eLazyBoolYes:
288             use_dynamic = lldb::eDynamicCanRunTarget;
289             break;
290         case eLazyBoolNo:
291             use_dynamic = lldb::eNoDynamicValues;
292             break;
293         }
294 
295         exe_results = m_exe_ctx.target->EvaluateExpression(expr, m_exe_ctx.frame, m_options.unwind_on_error, keep_in_memory, use_dynamic, result_valobj_sp);
296 
297         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
298         {
299             uint32_t start_frame = 0;
300             uint32_t num_frames = 1;
301             uint32_t num_frames_with_source = 0;
302             if (m_exe_ctx.thread)
303             {
304                 m_exe_ctx.thread->GetStatus (result->GetOutputStream(),
305                                              start_frame,
306                                              num_frames,
307                                              num_frames_with_source);
308             }
309             else if (m_exe_ctx.process)
310             {
311                 bool only_threads_with_stop_reason = true;
312                 m_exe_ctx.process->GetThreadStatus (result->GetOutputStream(),
313                                                     only_threads_with_stop_reason,
314                                                     start_frame,
315                                                     num_frames,
316                                                     num_frames_with_source);
317             }
318         }
319 
320         if (result_valobj_sp)
321         {
322             if (result_valobj_sp->GetError().Success())
323             {
324 
325                 result_valobj_sp.get()->SetIsExpressionResult(true);
326 
327                 if (m_options.format != eFormatDefault)
328                     result_valobj_sp->SetFormat (m_options.format);
329 
330                 ValueObject::DumpValueObject (*(output_stream),
331                                               result_valobj_sp.get(),   // Variable object to dump
332                                               result_valobj_sp->GetName().GetCString(),// Root object name
333                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
334                                               0,                        // Current depth, this is the top most, so zero...
335                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
336                                               m_options.show_types,     // Show types when dumping?
337                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
338                                               m_options.print_object,   // Print the objective C object?
339                                               use_dynamic,
340                                               true,                     // Use synthetic children if available
341                                               true,                     // Scope is already checked. Const results are always in scope.
342                                               false,                    // Don't flatten output
343                                               0,                        // Always use summaries (you might want an option --no-summary like there is for frame variable)
344                                               false);                   // Do not show more children than settings allow
345                 if (result)
346                     result->SetStatus (eReturnStatusSuccessFinishResult);
347             }
348             else
349             {
350                 const char *error_cstr = result_valobj_sp->GetError().AsCString();
351                 if (error_cstr && error_cstr[0])
352                 {
353                     int error_cstr_len = strlen (error_cstr);
354                     const bool ends_with_newline = error_cstr[error_cstr_len - 1] == '\n';
355                     if (strstr(error_cstr, "error:") != error_cstr)
356                         error_stream->PutCString ("error: ");
357                     error_stream->Write(error_cstr, error_cstr_len);
358                     if (!ends_with_newline)
359                         error_stream->EOL();
360                 }
361                 else
362                 {
363                     error_stream->PutCString ("error: unknown error\n");
364                 }
365 
366                 if (result)
367                     result->SetStatus (eReturnStatusFailed);
368             }
369         }
370     }
371     else
372     {
373         error_stream->Printf ("error: invalid execution context for expression\n");
374         return false;
375     }
376 
377     return true;
378 }
379 
380 bool
381 CommandObjectExpression::ExecuteRawCommandString
382 (
383     const char *command,
384     CommandReturnObject &result
385 )
386 {
387     m_exe_ctx = m_interpreter.GetExecutionContext();
388 
389     m_options.NotifyOptionParsingStarting();
390 
391     const char * expr = NULL;
392 
393     if (command[0] == '\0')
394     {
395         m_expr_lines.clear();
396         m_expr_line_count = 0;
397 
398         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
399         if (reader_sp)
400         {
401             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
402                                               this,                         // baton
403                                               eInputReaderGranularityLine,  // token size, to pass to callback function
404                                               NULL,                         // end token
405                                               NULL,                         // prompt
406                                               true));                       // echo input
407             if (err.Success())
408             {
409                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
410                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
411             }
412             else
413             {
414                 result.AppendError (err.AsCString());
415                 result.SetStatus (eReturnStatusFailed);
416             }
417         }
418         else
419         {
420             result.AppendError("out of memory");
421             result.SetStatus (eReturnStatusFailed);
422         }
423         return result.Succeeded();
424     }
425 
426     if (command[0] == '-')
427     {
428         // We have some options and these options MUST end with --.
429         const char *end_options = NULL;
430         const char *s = command;
431         while (s && s[0])
432         {
433             end_options = ::strstr (s, "--");
434             if (end_options)
435             {
436                 end_options += 2; // Get past the "--"
437                 if (::isspace (end_options[0]))
438                 {
439                     expr = end_options;
440                     while (::isspace (*expr))
441                         ++expr;
442                     break;
443                 }
444             }
445             s = end_options;
446         }
447 
448         if (end_options)
449         {
450             Args args (command, end_options - command);
451             if (!ParseOptions (args, result))
452                 return false;
453 
454             Error error (m_options.NotifyOptionParsingFinished());
455             if (error.Fail())
456             {
457                 result.AppendError (error.AsCString());
458                 result.SetStatus (eReturnStatusFailed);
459                 return false;
460             }
461         }
462     }
463 
464     if (expr == NULL)
465         expr = command;
466 
467     if (EvaluateExpression (expr, &(result.GetOutputStream()), &(result.GetErrorStream()), &result))
468         return true;
469 
470     result.SetStatus (eReturnStatusFailed);
471     return false;
472 }
473 
474 OptionDefinition
475 CommandObjectExpression::CommandOptions::g_option_table[] =
476 {
477 //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
478 //{ LLDB_OPT_SET_1, false, "format",     'f', required_argument, NULL, 0, "[ [bool|b] | [bin] | [char|c] | [oct|o] | [dec|i|d|u] | [hex|x] | [float|f] | [cstr|s] ]",  "Specify the format that the expression output should use."},
479 { LLDB_OPT_SET_1,   false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat, "Specify the format that the expression output should use."},
480 { LLDB_OPT_SET_2,   false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone,       "Print the object description of the value resulting from the expression."},
481 { LLDB_OPT_SET_2,   false, "dynamic-value",      'd', required_argument, NULL, 0, eArgTypeBoolean,    "Upcast the value resulting from the expression to its dynamic type if available."},
482 { LLDB_OPT_SET_ALL, false, "unwind-on-error",    'u', required_argument, NULL, 0, eArgTypeBoolean,    "Clean up program state if the expression causes a crash, breakpoint hit or signal."},
483 { LLDB_OPT_SET_ALL, false, "debug",              'g', no_argument,       NULL, 0, eArgTypeNone,       "Enable verbose debug logging of the expression parsing and evaluation."},
484 { LLDB_OPT_SET_ALL, false, "use-ir",             'i', no_argument,       NULL, 0, eArgTypeNone,       "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
485 { 0,                false, NULL,                 0,   0,                 NULL, 0, eArgTypeNone,       NULL }
486 };
487 
488