xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 6e8dc334db05a281f56753ce0fed054fbee68862)
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 
195     switch (notification)
196     {
197     case eInputReaderActivate:
198         reader.GetDebugger().GetOutputStream().Printf("%s\n", "Enter expressions, then terminate with an empty line to evaluate:");
199         // Fall through
200     case eInputReaderReactivate:
201         //if (out_fh)
202         //    reader.GetDebugger().GetOutputStream().Printf ("%3u: ", cmd_object_expr->m_expr_line_count);
203         break;
204 
205     case eInputReaderDeactivate:
206         break;
207 
208     case eInputReaderAsynchronousOutputWritten:
209         break;
210 
211     case eInputReaderGotToken:
212         ++cmd_object_expr->m_expr_line_count;
213         if (bytes && bytes_len)
214         {
215             cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
216         }
217 
218         if (bytes_len == 0)
219             reader.SetIsDone(true);
220         //else if (out_fh && !reader->IsDone())
221         //    ::fprintf (out_fh, "%3u: ", cmd_object_expr->m_expr_line_count);
222         break;
223 
224     case eInputReaderInterrupt:
225         cmd_object_expr->m_expr_lines.clear();
226         reader.SetIsDone (true);
227         reader.GetDebugger().GetOutputStream().Printf("%s\n", "Expression evaluation cancelled.");
228         break;
229 
230     case eInputReaderEndOfFile:
231         reader.SetIsDone (true);
232         break;
233 
234     case eInputReaderDone:
235 		if (cmd_object_expr->m_expr_lines.size() > 0)
236         {
237             StreamSP output_stream = reader.GetDebugger().GetAsyncOutputStream();
238             StreamSP error_stream = reader.GetDebugger().GetAsyncErrorStream();
239             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
240                                                  output_stream.get(),
241                                                  error_stream.get());
242             output_stream->Flush();
243             error_stream->Flush();
244         }
245         break;
246     }
247 
248     return bytes_len;
249 }
250 
251 bool
252 CommandObjectExpression::EvaluateExpression
253 (
254     const char *expr,
255     Stream *output_stream,
256     Stream *error_stream,
257     CommandReturnObject *result
258 )
259 {
260     if (m_exe_ctx.target)
261     {
262         lldb::ValueObjectSP result_valobj_sp;
263 
264         ExecutionResults exe_results;
265 
266         bool keep_in_memory = true;
267         lldb::DynamicValueType use_dynamic;
268         // If use dynamic is not set, get it from the target:
269         switch (m_options.use_dynamic)
270         {
271         case eLazyBoolCalculate:
272             use_dynamic = m_exe_ctx.target->GetPreferDynamicValue();
273             break;
274         case eLazyBoolYes:
275             use_dynamic = lldb::eDynamicCanRunTarget;
276             break;
277         case eLazyBoolNo:
278             use_dynamic = lldb::eNoDynamicValues;
279             break;
280         }
281 
282         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);
283 
284         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
285         {
286             uint32_t start_frame = 0;
287             uint32_t num_frames = 1;
288             uint32_t num_frames_with_source = 0;
289             if (m_exe_ctx.thread)
290             {
291                 m_exe_ctx.thread->GetStatus (result->GetOutputStream(),
292                                              start_frame,
293                                              num_frames,
294                                              num_frames_with_source);
295             }
296             else if (m_exe_ctx.process)
297             {
298                 bool only_threads_with_stop_reason = true;
299                 m_exe_ctx.process->GetThreadStatus (result->GetOutputStream(),
300                                                     only_threads_with_stop_reason,
301                                                     start_frame,
302                                                     num_frames,
303                                                     num_frames_with_source);
304             }
305         }
306 
307         if (result_valobj_sp)
308         {
309             if (result_valobj_sp->GetError().Success())
310             {
311                 if (m_options.format != eFormatDefault)
312                     result_valobj_sp->SetFormat (m_options.format);
313 
314                 ValueObject::DumpValueObject (*(output_stream),
315                                               result_valobj_sp.get(),   // Variable object to dump
316                                               result_valobj_sp->GetName().GetCString(),// Root object name
317                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
318                                               0,                        // Current depth, this is the top most, so zero...
319                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
320                                               m_options.show_types,     // Show types when dumping?
321                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
322                                               m_options.print_object,   // Print the objective C object?
323                                               use_dynamic,
324                                               true,                     // Scope is already checked. Const results are always in scope.
325                                               false);                   // Don't flatten output
326                 if (result)
327                     result->SetStatus (eReturnStatusSuccessFinishResult);
328             }
329             else
330             {
331                 error_stream->PutCString(result_valobj_sp->GetError().AsCString());
332                 if (result)
333                     result->SetStatus (eReturnStatusFailed);
334             }
335         }
336     }
337     else
338     {
339         error_stream->Printf ("error: invalid execution context for expression\n");
340         return false;
341     }
342 
343     return true;
344 }
345 
346 bool
347 CommandObjectExpression::ExecuteRawCommandString
348 (
349     const char *command,
350     CommandReturnObject &result
351 )
352 {
353     m_exe_ctx = m_interpreter.GetExecutionContext();
354 
355     m_options.NotifyOptionParsingStarting();
356 
357     const char * expr = NULL;
358 
359     if (command[0] == '\0')
360     {
361         m_expr_lines.clear();
362         m_expr_line_count = 0;
363 
364         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
365         if (reader_sp)
366         {
367             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
368                                               this,                         // baton
369                                               eInputReaderGranularityLine,  // token size, to pass to callback function
370                                               NULL,                         // end token
371                                               NULL,                         // prompt
372                                               true));                       // echo input
373             if (err.Success())
374             {
375                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
376                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
377             }
378             else
379             {
380                 result.AppendError (err.AsCString());
381                 result.SetStatus (eReturnStatusFailed);
382             }
383         }
384         else
385         {
386             result.AppendError("out of memory");
387             result.SetStatus (eReturnStatusFailed);
388         }
389         return result.Succeeded();
390     }
391 
392     if (command[0] == '-')
393     {
394         // We have some options and these options MUST end with --.
395         const char *end_options = NULL;
396         const char *s = command;
397         while (s && s[0])
398         {
399             end_options = ::strstr (s, "--");
400             if (end_options)
401             {
402                 end_options += 2; // Get past the "--"
403                 if (::isspace (end_options[0]))
404                 {
405                     expr = end_options;
406                     while (::isspace (*expr))
407                         ++expr;
408                     break;
409                 }
410             }
411             s = end_options;
412         }
413 
414         if (end_options)
415         {
416             Args args (command, end_options - command);
417             if (!ParseOptions (args, result))
418                 return false;
419 
420             Error error (m_options.NotifyOptionParsingFinished());
421             if (error.Fail())
422             {
423                 result.AppendError (error.AsCString());
424                 result.SetStatus (eReturnStatusFailed);
425                 return false;
426             }
427         }
428     }
429 
430     if (expr == NULL)
431         expr = command;
432 
433     if (EvaluateExpression (expr, &(result.GetOutputStream()), &(result.GetErrorStream()), &result))
434         return true;
435 
436     result.SetStatus (eReturnStatusFailed);
437     return false;
438 }
439 
440 OptionDefinition
441 CommandObjectExpression::CommandOptions::g_option_table[] =
442 {
443   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
444 //{ 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."},
445 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
446 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
447 { 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."},
448 { 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."},
449 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
450 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
451 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
452 };
453 
454