xref: /llvm-project/lldb/source/Commands/CommandObjectExpression.cpp (revision 8b2fe6dcbdf27b0df84ef4bdf514f9bc577c5804)
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 () :
41     Options()
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     Options::ResetOptionValues();
99     //language.Clear();
100     debug = false;
101     format = eFormatDefault;
102     print_object = false;
103     unwind_on_error = true;
104     show_types = true;
105     show_summary = true;
106 }
107 
108 const lldb::OptionDefinition*
109 CommandObjectExpression::CommandOptions::GetDefinitions ()
110 {
111     return g_option_table;
112 }
113 
114 CommandObjectExpression::CommandObjectExpression (CommandInterpreter &interpreter) :
115     CommandObject (interpreter,
116                    "expression",
117                    "Evaluate a C/ObjC/C++ expression in the current program context, using variables currently in scope.",
118                    NULL),
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         lldb::ExecutionResults exe_results;
240         exe_results = m_exe_ctx.target->EvaluateExpression(expr, m_exe_ctx.frame, m_options.unwind_on_error, result_valobj_sp);
241 
242         if (exe_results == eExecutionInterrupted && !m_options.unwind_on_error)
243         {
244             if (m_exe_ctx.thread)
245                 lldb_private::DisplayThreadInfo (m_interpreter, result->GetOutputStream(), m_exe_ctx.thread, false, true);
246             else
247                 lldb_private::DisplayThreadsInfo (m_interpreter, &m_exe_ctx, *result, true, true);
248         }
249 
250         if (result_valobj_sp)
251         {
252             if (result_valobj_sp->GetError().Success())
253             {
254                 if (m_options.format != eFormatDefault)
255                     result_valobj_sp->SetFormat (m_options.format);
256 
257                 ValueObject::DumpValueObject (output_stream,
258                                               m_exe_ctx.GetBestExecutionContextScope(),
259                                               result_valobj_sp.get(),   // Variable object to dump
260                                               result_valobj_sp->GetName().GetCString(),// Root object name
261                                               0,                        // Pointer depth to traverse (zero means stop at pointers)
262                                               0,                        // Current depth, this is the top most, so zero...
263                                               UINT32_MAX,               // Max depth to go when dumping concrete types, dump everything...
264                                               m_options.show_types,     // Show types when dumping?
265                                               false,                    // Show locations of variables, no since this is a host address which we don't care to see
266                                               m_options.print_object,   // Print the objective C object?
267                                               true,                     // Scope is already checked. Const results are always in scope.
268                                               false);                   // Don't flatten output
269                 if (result)
270                     result->SetStatus (eReturnStatusSuccessFinishResult);
271             }
272             else
273             {
274                 error_stream.PutCString(result_valobj_sp->GetError().AsCString());
275                 if (result)
276                     result->SetStatus (eReturnStatusFailed);
277             }
278         }
279     }
280     else
281     {
282         error_stream.Printf ("error: invalid execution context for expression\n");
283         return false;
284     }
285 
286     return true;
287 }
288 
289 bool
290 CommandObjectExpression::ExecuteRawCommandString
291 (
292     const char *command,
293     CommandReturnObject &result
294 )
295 {
296     m_exe_ctx = m_interpreter.GetDebugger().GetExecutionContext();
297 
298     m_options.ResetOptionValues();
299 
300     const char * expr = NULL;
301 
302     if (command[0] == '\0')
303     {
304         m_expr_lines.clear();
305         m_expr_line_count = 0;
306 
307         InputReaderSP reader_sp (new InputReader(m_interpreter.GetDebugger()));
308         if (reader_sp)
309         {
310             Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
311                                               this,                         // baton
312                                               eInputReaderGranularityLine,  // token size, to pass to callback function
313                                               NULL,                         // end token
314                                               NULL,                         // prompt
315                                               true));                       // echo input
316             if (err.Success())
317             {
318                 m_interpreter.GetDebugger().PushInputReader (reader_sp);
319                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
320             }
321             else
322             {
323                 result.AppendError (err.AsCString());
324                 result.SetStatus (eReturnStatusFailed);
325             }
326         }
327         else
328         {
329             result.AppendError("out of memory");
330             result.SetStatus (eReturnStatusFailed);
331         }
332         return result.Succeeded();
333     }
334 
335     if (command[0] == '-')
336     {
337         // We have some options and these options MUST end with --.
338         const char *end_options = NULL;
339         const char *s = command;
340         while (s && s[0])
341         {
342             end_options = ::strstr (s, "--");
343             if (end_options)
344             {
345                 end_options += 2; // Get past the "--"
346                 if (::isspace (end_options[0]))
347                 {
348                     expr = end_options;
349                     while (::isspace (*expr))
350                         ++expr;
351                     break;
352                 }
353             }
354             s = end_options;
355         }
356 
357         if (end_options)
358         {
359             Args args (command, end_options - command);
360             if (!ParseOptions (args, result))
361                 return false;
362         }
363     }
364 
365     if (expr == NULL)
366         expr = command;
367 
368     if (EvaluateExpression (expr, result.GetOutputStream(), result.GetErrorStream(), &result))
369         return true;
370 
371     result.SetStatus (eReturnStatusFailed);
372     return false;
373 }
374 
375 lldb::OptionDefinition
376 CommandObjectExpression::CommandOptions::g_option_table[] =
377 {
378   //{ LLDB_OPT_SET_ALL, false, "language",   'l', required_argument, NULL, 0, "[c|c++|objc|objc++]",          "Sets the language to use when parsing the expression."},
379 //{ 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."},
380 { LLDB_OPT_SET_1, false, "format",             'f', required_argument, NULL, 0, eArgTypeExprFormat,  "Specify the format that the expression output should use."},
381 { LLDB_OPT_SET_2, false, "object-description", 'o', no_argument,       NULL, 0, eArgTypeNone, "Print the object description of the value resulting from the expression."},
382 { 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."},
383 { LLDB_OPT_SET_ALL, false, "debug",            'g', no_argument,       NULL, 0, eArgTypeNone, "Enable verbose debug logging of the expression parsing and evaluation."},
384 { LLDB_OPT_SET_ALL, false, "use-ir",           'i', no_argument,       NULL, 0, eArgTypeNone, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
385 { 0, false, NULL, 0, 0, NULL, NULL, eArgTypeNone, NULL }
386 };
387 
388