xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 5fd05903d488cc91dc53c40bc0c7e802b4998ce8)
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 out_stream = reader.GetDebugger().GetAsyncOutputStream();
202             out_stream->Printf("%s\n", "Enter expressions, then terminate with an empty line to evaluate:");
203             out_stream->Flush();
204         }
205         // Fall through
206     case eInputReaderReactivate:
207         break;
208 
209     case eInputReaderDeactivate:
210         break;
211 
212     case eInputReaderAsynchronousOutputWritten:
213         break;
214 
215     case eInputReaderGotToken:
216         ++cmd_object_expr->m_expr_line_count;
217         if (bytes && bytes_len)
218         {
219             cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
220         }
221 
222         if (bytes_len == 0)
223             reader.SetIsDone(true);
224         break;
225 
226     case eInputReaderInterrupt:
227         cmd_object_expr->m_expr_lines.clear();
228         reader.SetIsDone (true);
229         if (!batch_mode)
230         {
231             StreamSP out_stream = reader.GetDebugger().GetAsyncOutputStream();
232             out_stream->Printf("%s\n", "Expression evaluation cancelled.");
233             out_stream->Flush();
234         }
235         break;
236 
237     case eInputReaderEndOfFile:
238         reader.SetIsDone (true);
239         break;
240 
241     case eInputReaderDone:
242 		if (cmd_object_expr->m_expr_lines.size() > 0)
243         {
244             StreamSP output_stream = reader.GetDebugger().GetAsyncOutputStream();
245             StreamSP error_stream = reader.GetDebugger().GetAsyncErrorStream();
246             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
247                                                  output_stream.get(),
248                                                  error_stream.get());
249             output_stream->Flush();
250             error_stream->Flush();
251         }
252         break;
253     }
254 
255     return bytes_len;
256 }
257 
258 bool
259 CommandObjectExpression::EvaluateExpression
260 (
261     const char *expr,
262     Stream *output_stream,
263     Stream *error_stream,
264     CommandReturnObject *result
265 )
266 {
267     if (m_exe_ctx.target)
268     {
269         lldb::ValueObjectSP result_valobj_sp;
270 
271         ExecutionResults exe_results;
272 
273         bool keep_in_memory = true;
274         lldb::DynamicValueType use_dynamic;
275         // If use dynamic is not set, get it from the target:
276         switch (m_options.use_dynamic)
277         {
278         case eLazyBoolCalculate:
279             use_dynamic = m_exe_ctx.target->GetPreferDynamicValue();
280             break;
281         case eLazyBoolYes:
282             use_dynamic = lldb::eDynamicCanRunTarget;
283             break;
284         case eLazyBoolNo:
285             use_dynamic = lldb::eNoDynamicValues;
286             break;
287         }
288 
289         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);
290 
291         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
292         {
293             uint32_t start_frame = 0;
294             uint32_t num_frames = 1;
295             uint32_t num_frames_with_source = 0;
296             if (m_exe_ctx.thread)
297             {
298                 m_exe_ctx.thread->GetStatus (result->GetOutputStream(),
299                                              start_frame,
300                                              num_frames,
301                                              num_frames_with_source);
302             }
303             else if (m_exe_ctx.process)
304             {
305                 bool only_threads_with_stop_reason = true;
306                 m_exe_ctx.process->GetThreadStatus (result->GetOutputStream(),
307                                                     only_threads_with_stop_reason,
308                                                     start_frame,
309                                                     num_frames,
310                                                     num_frames_with_source);
311             }
312         }
313 
314         if (result_valobj_sp)
315         {
316             if (result_valobj_sp->GetError().Success())
317             {
318                 if (m_options.format != eFormatDefault)
319                     result_valobj_sp->SetFormat (m_options.format);
320 
321                 ValueObject::DumpValueObject (*(output_stream),
322                                               result_valobj_sp.get(),   // Variable object to dump
323                                               result_valobj_sp->GetName().GetCString(),// Root object name
324                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
325                                               0,                        // Current depth, this is the top most, so zero...
326                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
327                                               m_options.show_types,     // Show types when dumping?
328                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
329                                               m_options.print_object,   // Print the objective C object?
330                                               use_dynamic,
331                                               true,                     // Scope is already checked. Const results are always in scope.
332                                               false);                   // Don't flatten output
333                 if (result)
334                     result->SetStatus (eReturnStatusSuccessFinishResult);
335             }
336             else
337             {
338                 const char *error_cstr = result_valobj_sp->GetError().AsCString();
339                 if (error_cstr && error_cstr[0])
340                 {
341                     int error_cstr_len = strlen (error_cstr);
342                     const bool ends_with_newline = error_cstr[error_cstr_len - 1] == '\n';
343                     if (strstr(error_cstr, "error:") != error_cstr)
344                         error_stream->PutCString ("error: ");
345                     error_stream->Write(error_cstr, error_cstr_len);
346                     if (!ends_with_newline)
347                         error_stream->EOL();
348                 }
349                 else
350                 {
351                     error_stream->PutCString ("error: unknown error\n");
352                 }
353 
354                 if (result)
355                     result->SetStatus (eReturnStatusFailed);
356             }
357         }
358     }
359     else
360     {
361         error_stream->Printf ("error: invalid execution context for expression\n");
362         return false;
363     }
364 
365     return true;
366 }
367 
368 bool
369 CommandObjectExpression::ExecuteRawCommandString
370 (
371     const char *command,
372     CommandReturnObject &result
373 )
374 {
375     m_exe_ctx = m_interpreter.GetExecutionContext();
376 
377     m_options.NotifyOptionParsingStarting();
378 
379     const char * expr = NULL;
380 
381     if (command[0] == '\0')
382     {
383         m_expr_lines.clear();
384         m_expr_line_count = 0;
385 
386         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
387         if (reader_sp)
388         {
389             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
390                                               this,                         // baton
391                                               eInputReaderGranularityLine,  // token size, to pass to callback function
392                                               NULL,                         // end token
393                                               NULL,                         // prompt
394                                               true));                       // echo input
395             if (err.Success())
396             {
397                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
398                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
399             }
400             else
401             {
402                 result.AppendError (err.AsCString());
403                 result.SetStatus (eReturnStatusFailed);
404             }
405         }
406         else
407         {
408             result.AppendError("out of memory");
409             result.SetStatus (eReturnStatusFailed);
410         }
411         return result.Succeeded();
412     }
413 
414     if (command[0] == '-')
415     {
416         // We have some options and these options MUST end with --.
417         const char *end_options = NULL;
418         const char *s = command;
419         while (s && s[0])
420         {
421             end_options = ::strstr (s, "--");
422             if (end_options)
423             {
424                 end_options += 2; // Get past the "--"
425                 if (::isspace (end_options[0]))
426                 {
427                     expr = end_options;
428                     while (::isspace (*expr))
429                         ++expr;
430                     break;
431                 }
432             }
433             s = end_options;
434         }
435 
436         if (end_options)
437         {
438             Args args (command, end_options - command);
439             if (!ParseOptions (args, result))
440                 return false;
441 
442             Error error (m_options.NotifyOptionParsingFinished());
443             if (error.Fail())
444             {
445                 result.AppendError (error.AsCString());
446                 result.SetStatus (eReturnStatusFailed);
447                 return false;
448             }
449         }
450     }
451 
452     if (expr == NULL)
453         expr = command;
454 
455     if (EvaluateExpression (expr, &(result.GetOutputStream()), &(result.GetErrorStream()), &result))
456         return true;
457 
458     result.SetStatus (eReturnStatusFailed);
459     return false;
460 }
461 
462 OptionDefinition
463 CommandObjectExpression::CommandOptions::g_option_table[] =
464 {
465   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
466 //{ 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."},
467 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
468 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
469 { 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."},
470 { 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."},
471 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
472 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
473 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
474 };
475 
476