xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision eb0103f2d08a13812614da6f4dc3f6bb80c7aa21)
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(m_interpreter)
42 {
43     // Keep only one place to reset the values to their defaults
44     ResetOptionValues();
45 }
46 
47 
48 CommandObjectExpression::CommandOptions::~CommandOptions ()
49 {
50 }
51 
52 Error
53 CommandObjectExpression::CommandOptions::SetOptionValue (int 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 'u':
81         bool success;
82         unwind_on_error = Args::StringToBoolean(option_arg, true, &success);
83         if (!success)
84             error.SetErrorStringWithFormat("Could not convert \"%s\" to a boolean value.", option_arg);
85         break;
86 
87     default:
88         error.SetErrorStringWithFormat("Invalid short option character '%c'.\n", short_option);
89         break;
90     }
91 
92     return error;
93 }
94 
95 void
96 CommandObjectExpression::CommandOptions::ResetOptionValues ()
97 {
98     //language.Clear();
99     debug = false;
100     format = eFormatDefault;
101     print_object = false;
102     unwind_on_error = true;
103     show_types = true;
104     show_summary = true;
105 }
106 
107 const OptionDefinition*
108 CommandObjectExpression::CommandOptions::GetDefinitions ()
109 {
110     return g_option_table;
111 }
112 
113 CommandObjectExpression::CommandObjectExpression (CommandInterpreter &interpreter) :
114     CommandObject (interpreter,
115                    "expression",
116                    "Evaluate a C/ObjC/C++ expression in the current program context, using variables currently in scope.",
117                    NULL),
118     m_options (interpreter),
119     m_expr_line_count (0),
120     m_expr_lines ()
121 {
122   SetHelpLong(
123 "Examples: \n\
124 \n\
125    expr my_struct->a = my_array[3] \n\
126    expr -f bin -- (index * 8) + 5 \n\
127    expr char c[] = \"foo\"; c[0]\n");
128 
129     CommandArgumentEntry arg;
130     CommandArgumentData expression_arg;
131 
132     // Define the first (and only) variant of this arg.
133     expression_arg.arg_type = eArgTypeExpression;
134     expression_arg.arg_repetition = eArgRepeatPlain;
135 
136     // There is only one variant this argument could be; put it into the argument entry.
137     arg.push_back (expression_arg);
138 
139     // Push the data for the first argument into the m_arguments vector.
140     m_arguments.push_back (arg);
141 }
142 
143 CommandObjectExpression::~CommandObjectExpression ()
144 {
145 }
146 
147 Options *
148 CommandObjectExpression::GetOptions ()
149 {
150     return &m_options;
151 }
152 
153 
154 bool
155 CommandObjectExpression::Execute
156 (
157     Args& command,
158     CommandReturnObject &result
159 )
160 {
161     return false;
162 }
163 
164 
165 size_t
166 CommandObjectExpression::MultiLineExpressionCallback
167 (
168     void *baton,
169     InputReader &reader,
170     lldb::InputReaderAction notification,
171     const char *bytes,
172     size_t bytes_len
173 )
174 {
175     CommandObjectExpression *cmd_object_expr = (CommandObjectExpression *) baton;
176 
177     switch (notification)
178     {
179     case eInputReaderActivate:
180         reader.GetDebugger().GetOutputStream().Printf("%s\n", "Enter expressions, then terminate with an empty line to evaluate:");
181         // Fall through
182     case eInputReaderReactivate:
183         //if (out_fh)
184         //    reader.GetDebugger().GetOutputStream().Printf ("%3u: ", cmd_object_expr->m_expr_line_count);
185         break;
186 
187     case eInputReaderDeactivate:
188         break;
189 
190     case eInputReaderGotToken:
191         ++cmd_object_expr->m_expr_line_count;
192         if (bytes && bytes_len)
193         {
194             cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
195         }
196 
197         if (bytes_len == 0)
198             reader.SetIsDone(true);
199         //else if (out_fh && !reader->IsDone())
200         //    ::fprintf (out_fh, "%3u: ", cmd_object_expr->m_expr_line_count);
201         break;
202 
203     case eInputReaderInterrupt:
204         cmd_object_expr->m_expr_lines.clear();
205         reader.SetIsDone (true);
206         reader.GetDebugger().GetOutputStream().Printf("%s\n", "Expression evaluation cancelled.");
207         break;
208 
209     case eInputReaderEndOfFile:
210         reader.SetIsDone (true);
211         break;
212 
213     case eInputReaderDone:
214 		if (cmd_object_expr->m_expr_lines.size() > 0)
215         {
216             cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
217                                                  reader.GetDebugger().GetOutputStream(),
218                                                  reader.GetDebugger().GetErrorStream());
219         }
220         break;
221     }
222 
223     return bytes_len;
224 }
225 
226 bool
227 CommandObjectExpression::EvaluateExpression
228 (
229     const char *expr,
230     Stream &output_stream,
231     Stream &error_stream,
232     CommandReturnObject *result
233 )
234 {
235     if (m_exe_ctx.target)
236     {
237         lldb::ValueObjectSP result_valobj_sp;
238 
239         ExecutionResults exe_results;
240 
241         bool keep_in_memory = true;
242 
243         exe_results = m_exe_ctx.target->EvaluateExpression(expr, m_exe_ctx.frame, m_options.unwind_on_error, keep_in_memory, result_valobj_sp);
244 
245         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
246         {
247             if (m_exe_ctx.thread)
248                 lldb_private::DisplayThreadInfo (m_interpreter, result->GetOutputStream(), m_exe_ctx.thread, false, true);
249             else
250                 lldb_private::DisplayThreadsInfo (m_interpreter, &m_exe_ctx, *result, true, true);
251         }
252 
253         if (result_valobj_sp)
254         {
255             if (result_valobj_sp->GetError().Success())
256             {
257                 if (m_options.format != eFormatDefault)
258                     result_valobj_sp->SetFormat (m_options.format);
259 
260                 ValueObject::DumpValueObject (output_stream,
261                                               result_valobj_sp.get(),   // Variable object to dump
262                                               result_valobj_sp->GetName().GetCString(),// Root object name
263                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
264                                               0,                        // Current depth, this is the top most, so zero...
265                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
266                                               m_options.show_types,     // Show types when dumping?
267                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
268                                               m_options.print_object,   // Print the objective C object?
269                                               true,                     // Scope is already checked. Const results are always in scope.
270                                               false);                   // Don't flatten output
271                 if (result)
272                     result->SetStatus (eReturnStatusSuccessFinishResult);
273             }
274             else
275             {
276                 error_stream.PutCString(result_valobj_sp->GetError().AsCString());
277                 if (result)
278                     result->SetStatus (eReturnStatusFailed);
279             }
280         }
281     }
282     else
283     {
284         error_stream.Printf ("error: invalid execution context for expression\n");
285         return false;
286     }
287 
288     return true;
289 }
290 
291 bool
292 CommandObjectExpression::ExecuteRawCommandString
293 (
294     const char *command,
295     CommandReturnObject &result
296 )
297 {
298     m_exe_ctx = m_interpreter.GetDebugger().GetExecutionContext();
299 
300     m_options.Reset();
301 
302     const char * expr = NULL;
303 
304     if (command[0] == '\0')
305     {
306         m_expr_lines.clear();
307         m_expr_line_count = 0;
308 
309         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
310         if (reader_sp)
311         {
312             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
313                                               this,                         // baton
314                                               eInputReaderGranularityLine,  // token size, to pass to callback function
315                                               NULL,                         // end token
316                                               NULL,                         // prompt
317                                               true));                       // echo input
318             if (err.Success())
319             {
320                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
321                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
322             }
323             else
324             {
325                 result.AppendError (err.AsCString());
326                 result.SetStatus (eReturnStatusFailed);
327             }
328         }
329         else
330         {
331             result.AppendError("out of memory");
332             result.SetStatus (eReturnStatusFailed);
333         }
334         return result.Succeeded();
335     }
336 
337     if (command[0] == '-')
338     {
339         // We have some options and these options MUST end with --.
340         const char *end_options = NULL;
341         const char *s = command;
342         while (s && s[0])
343         {
344             end_options = ::strstr (s, "--");
345             if (end_options)
346             {
347                 end_options += 2; // Get past the "--"
348                 if (::isspace (end_options[0]))
349                 {
350                     expr = end_options;
351                     while (::isspace (*expr))
352                         ++expr;
353                     break;
354                 }
355             }
356             s = end_options;
357         }
358 
359         if (end_options)
360         {
361             Args args (command, end_options - command);
362             if (!ParseOptions (args, result))
363                 return false;
364         }
365     }
366 
367     if (expr == NULL)
368         expr = command;
369 
370     if (EvaluateExpression (expr, result.GetOutputStream(), result.GetErrorStream(), &result))
371         return true;
372 
373     result.SetStatus (eReturnStatusFailed);
374     return false;
375 }
376 
377 OptionDefinition
378 CommandObjectExpression::CommandOptions::g_option_table[] =
379 {
380   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
381 //{ 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."},
382 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
383 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
384 { 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."},
385 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
386 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
387 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
388 };
389 
390