xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 78a685aa2d8bbf48f25f2f93d4c0a74652eb0e9b)
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 "CommandObjectThread.h" // For DisplayThreadInfo.
17 #include "lldb/Interpreter/Args.h"
18 #include "lldb/Core/Value.h"
19 #include "lldb/Core/InputReader.h"
20 #include "lldb/Core/ValueObjectVariable.h"
21 #include "lldb/Expression/ClangExpressionVariable.h"
22 #include "lldb/Expression/ClangUserExpression.h"
23 #include "lldb/Expression/ClangFunction.h"
24 #include "lldb/Expression/DWARFExpression.h"
25 #include "lldb/Host/Host.h"
26 #include "lldb/Core/Debugger.h"
27 #include "lldb/Interpreter/CommandInterpreter.h"
28 #include "lldb/Interpreter/CommandReturnObject.h"
29 #include "lldb/Target/ObjCLanguageRuntime.h"
30 #include "lldb/Symbol/ObjectFile.h"
31 #include "lldb/Symbol/Variable.h"
32 #include "lldb/Target/Process.h"
33 #include "lldb/Target/StackFrame.h"
34 #include "lldb/Target/Target.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);
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 eInputReaderGotToken:
209         ++cmd_object_expr->m_expr_line_count;
210         if (bytes && bytes_len)
211         {
212             cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
213         }
214 
215         if (bytes_len == 0)
216             reader.SetIsDone(true);
217         //else if (out_fh && !reader->IsDone())
218         //    ::fprintf (out_fh, "%3u: ", cmd_object_expr->m_expr_line_count);
219         break;
220 
221     case eInputReaderInterrupt:
222         cmd_object_expr->m_expr_lines.clear();
223         reader.SetIsDone (true);
224         reader.GetDebugger().GetOutputStream().Printf("%s\n", "Expression evaluation cancelled.");
225         break;
226 
227     case eInputReaderEndOfFile:
228         reader.SetIsDone (true);
229         break;
230 
231     case eInputReaderDone:
232 		if (cmd_object_expr->m_expr_lines.size() > 0)
233         {
234             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
235                                                  reader.GetDebugger().GetOutputStream(),
236                                                  reader.GetDebugger().GetErrorStream());
237         }
238         break;
239     }
240 
241     return bytes_len;
242 }
243 
244 bool
245 CommandObjectExpression::EvaluateExpression
246 (
247     const char *expr,
248     Stream &output_stream,
249     Stream &error_stream,
250     CommandReturnObject *result
251 )
252 {
253     if (m_exe_ctx.target)
254     {
255         lldb::ValueObjectSP result_valobj_sp;
256 
257         ExecutionResults exe_results;
258 
259         bool keep_in_memory = true;
260         bool use_dynamic;
261         // If use dynamic is not set, get it from the target:
262         switch (m_options.use_dynamic)
263         {
264         case eLazyBoolCalculate:
265             {
266                 if (m_exe_ctx.target->GetPreferDynamicValue())
267                     use_dynamic = true;
268                 else
269                     use_dynamic = false;
270             }
271             break;
272         case eLazyBoolYes:
273             use_dynamic = true;
274             break;
275         case eLazyBoolNo:
276             use_dynamic = false;
277             break;
278         }
279 
280         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);
281 
282         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
283         {
284             if (m_exe_ctx.thread)
285                 lldb_private::DisplayThreadInfo (m_interpreter, result->GetOutputStream(), m_exe_ctx.thread, false, true);
286             else
287                 lldb_private::DisplayThreadsInfo (m_interpreter, &m_exe_ctx, *result, true, true);
288         }
289 
290         if (result_valobj_sp)
291         {
292             if (result_valobj_sp->GetError().Success())
293             {
294                 if (m_options.format != eFormatDefault)
295                     result_valobj_sp->SetFormat (m_options.format);
296 
297                 ValueObject::DumpValueObject (output_stream,
298                                               result_valobj_sp.get(),   // Variable object to dump
299                                               result_valobj_sp->GetName().GetCString(),// Root object name
300                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
301                                               0,                        // Current depth, this is the top most, so zero...
302                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
303                                               m_options.show_types,     // Show types when dumping?
304                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
305                                               m_options.print_object,   // Print the objective C object?
306                                               use_dynamic,
307                                               true,                     // Scope is already checked. Const results are always in scope.
308                                               false);                   // Don't flatten output
309                 if (result)
310                     result->SetStatus (eReturnStatusSuccessFinishResult);
311             }
312             else
313             {
314                 error_stream.PutCString(result_valobj_sp->GetError().AsCString());
315                 if (result)
316                     result->SetStatus (eReturnStatusFailed);
317             }
318         }
319     }
320     else
321     {
322         error_stream.Printf ("error: invalid execution context for expression\n");
323         return false;
324     }
325 
326     return true;
327 }
328 
329 bool
330 CommandObjectExpression::ExecuteRawCommandString
331 (
332     const char *command,
333     CommandReturnObject &result
334 )
335 {
336     m_exe_ctx = m_interpreter.GetExecutionContext();
337 
338     m_options.NotifyOptionParsingStarting();
339 
340     const char * expr = NULL;
341 
342     if (command[0] == '\0')
343     {
344         m_expr_lines.clear();
345         m_expr_line_count = 0;
346 
347         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
348         if (reader_sp)
349         {
350             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
351                                               this,                         // baton
352                                               eInputReaderGranularityLine,  // token size, to pass to callback function
353                                               NULL,                         // end token
354                                               NULL,                         // prompt
355                                               true));                       // echo input
356             if (err.Success())
357             {
358                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
359                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
360             }
361             else
362             {
363                 result.AppendError (err.AsCString());
364                 result.SetStatus (eReturnStatusFailed);
365             }
366         }
367         else
368         {
369             result.AppendError("out of memory");
370             result.SetStatus (eReturnStatusFailed);
371         }
372         return result.Succeeded();
373     }
374 
375     if (command[0] == '-')
376     {
377         // We have some options and these options MUST end with --.
378         const char *end_options = NULL;
379         const char *s = command;
380         while (s && s[0])
381         {
382             end_options = ::strstr (s, "--");
383             if (end_options)
384             {
385                 end_options += 2; // Get past the "--"
386                 if (::isspace (end_options[0]))
387                 {
388                     expr = end_options;
389                     while (::isspace (*expr))
390                         ++expr;
391                     break;
392                 }
393             }
394             s = end_options;
395         }
396 
397         if (end_options)
398         {
399             Args args (command, end_options - command);
400             if (!ParseOptions (args, result))
401                 return false;
402 
403             Error error (m_options.NotifyOptionParsingFinished());
404             if (error.Fail())
405             {
406                 result.AppendError (error.AsCString());
407                 result.SetStatus (eReturnStatusFailed);
408                 return false;
409             }
410         }
411     }
412 
413     if (expr == NULL)
414         expr = command;
415 
416     if (EvaluateExpression (expr, result.GetOutputStream(), result.GetErrorStream(), &result))
417         return true;
418 
419     result.SetStatus (eReturnStatusFailed);
420     return false;
421 }
422 
423 OptionDefinition
424 CommandObjectExpression::CommandOptions::g_option_table[] =
425 {
426   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
427 //{ 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."},
428 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
429 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
430 { 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."},
431 { 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."},
432 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
433 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
434 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
435 };
436 
437