xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 969ed3d10f2bed3ef9c4d53114594827fefecf68)
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             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
238                                                  reader.GetDebugger().GetOutputStream(),
239                                                  reader.GetDebugger().GetErrorStream());
240         }
241         break;
242     }
243 
244     return bytes_len;
245 }
246 
247 bool
248 CommandObjectExpression::EvaluateExpression
249 (
250     const char *expr,
251     Stream &output_stream,
252     Stream &error_stream,
253     CommandReturnObject *result
254 )
255 {
256     if (m_exe_ctx.target)
257     {
258         lldb::ValueObjectSP result_valobj_sp;
259 
260         ExecutionResults exe_results;
261 
262         bool keep_in_memory = true;
263         bool use_dynamic;
264         // If use dynamic is not set, get it from the target:
265         switch (m_options.use_dynamic)
266         {
267         case eLazyBoolCalculate:
268             {
269                 if (m_exe_ctx.target->GetPreferDynamicValue())
270                     use_dynamic = true;
271                 else
272                     use_dynamic = false;
273             }
274             break;
275         case eLazyBoolYes:
276             use_dynamic = true;
277             break;
278         case eLazyBoolNo:
279             use_dynamic = false;
280             break;
281         }
282 
283         exe_results = m_exe_ctx.target->EvaluateExpression(expr, m_exe_ctx.frame, m_options.unwind_on_error, use_dynamic, keep_in_memory, result_valobj_sp);
284 
285         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
286         {
287             uint32_t start_frame = 0;
288             uint32_t num_frames = 1;
289             uint32_t num_frames_with_source = 0;
290             if (m_exe_ctx.thread)
291             {
292                 m_exe_ctx.thread->GetStatus (result->GetOutputStream(),
293                                              start_frame,
294                                              num_frames,
295                                              num_frames_with_source);
296             }
297             else if (m_exe_ctx.process)
298             {
299                 bool only_threads_with_stop_reason = true;
300                 m_exe_ctx.process->GetThreadStatus (result->GetOutputStream(),
301                                                     only_threads_with_stop_reason,
302                                                     start_frame,
303                                                     num_frames,
304                                                     num_frames_with_source);
305             }
306         }
307 
308         if (result_valobj_sp)
309         {
310             if (result_valobj_sp->GetError().Success())
311             {
312                 if (m_options.format != eFormatDefault)
313                     result_valobj_sp->SetFormat (m_options.format);
314 
315                 ValueObject::DumpValueObject (output_stream,
316                                               result_valobj_sp.get(),   // Variable object to dump
317                                               result_valobj_sp->GetName().GetCString(),// Root object name
318                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
319                                               0,                        // Current depth, this is the top most, so zero...
320                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
321                                               m_options.show_types,     // Show types when dumping?
322                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
323                                               m_options.print_object,   // Print the objective C object?
324                                               use_dynamic,
325                                               true,                     // Scope is already checked. Const results are always in scope.
326                                               false);                   // Don't flatten output
327                 if (result)
328                     result->SetStatus (eReturnStatusSuccessFinishResult);
329             }
330             else
331             {
332                 error_stream.PutCString(result_valobj_sp->GetError().AsCString());
333                 if (result)
334                     result->SetStatus (eReturnStatusFailed);
335             }
336         }
337     }
338     else
339     {
340         error_stream.Printf ("error: invalid execution context for expression\n");
341         return false;
342     }
343 
344     return true;
345 }
346 
347 bool
348 CommandObjectExpression::ExecuteRawCommandString
349 (
350     const char *command,
351     CommandReturnObject &result
352 )
353 {
354     m_exe_ctx = m_interpreter.GetExecutionContext();
355 
356     m_options.NotifyOptionParsingStarting();
357 
358     const char * expr = NULL;
359 
360     if (command[0] == '\0')
361     {
362         m_expr_lines.clear();
363         m_expr_line_count = 0;
364 
365         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
366         if (reader_sp)
367         {
368             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
369                                               this,                         // baton
370                                               eInputReaderGranularityLine,  // token size, to pass to callback function
371                                               NULL,                         // end token
372                                               NULL,                         // prompt
373                                               true));                       // echo input
374             if (err.Success())
375             {
376                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
377                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
378             }
379             else
380             {
381                 result.AppendError (err.AsCString());
382                 result.SetStatus (eReturnStatusFailed);
383             }
384         }
385         else
386         {
387             result.AppendError("out of memory");
388             result.SetStatus (eReturnStatusFailed);
389         }
390         return result.Succeeded();
391     }
392 
393     if (command[0] == '-')
394     {
395         // We have some options and these options MUST end with --.
396         const char *end_options = NULL;
397         const char *s = command;
398         while (s && s[0])
399         {
400             end_options = ::strstr (s, "--");
401             if (end_options)
402             {
403                 end_options += 2; // Get past the "--"
404                 if (::isspace (end_options[0]))
405                 {
406                     expr = end_options;
407                     while (::isspace (*expr))
408                         ++expr;
409                     break;
410                 }
411             }
412             s = end_options;
413         }
414 
415         if (end_options)
416         {
417             Args args (command, end_options - command);
418             if (!ParseOptions (args, result))
419                 return false;
420 
421             Error error (m_options.NotifyOptionParsingFinished());
422             if (error.Fail())
423             {
424                 result.AppendError (error.AsCString());
425                 result.SetStatus (eReturnStatusFailed);
426                 return false;
427             }
428         }
429     }
430 
431     if (expr == NULL)
432         expr = command;
433 
434     if (EvaluateExpression (expr, result.GetOutputStream(), result.GetErrorStream(), &result))
435         return true;
436 
437     result.SetStatus (eReturnStatusFailed);
438     return false;
439 }
440 
441 OptionDefinition
442 CommandObjectExpression::CommandOptions::g_option_table[] =
443 {
444   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
445 //{ 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."},
446 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
447 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
448 { 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."},
449 { 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."},
450 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
451 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
452 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
453 };
454 
455