1 //===-- CommandInterpreter.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 <string>
11 #include <vector>
12 
13 #include <getopt.h>
14 #include <stdlib.h>
15 
16 #include "CommandObjectScript.h"
17 #include "lldb/Interpreter/CommandObjectRegexCommand.h"
18 
19 #include "../Commands/CommandObjectApropos.h"
20 #include "../Commands/CommandObjectArgs.h"
21 #include "../Commands/CommandObjectBreakpoint.h"
22 #include "../Commands/CommandObjectDisassemble.h"
23 #include "../Commands/CommandObjectExpression.h"
24 #include "../Commands/CommandObjectFrame.h"
25 #include "../Commands/CommandObjectHelp.h"
26 #include "../Commands/CommandObjectLog.h"
27 #include "../Commands/CommandObjectMemory.h"
28 #include "../Commands/CommandObjectPlatform.h"
29 #include "../Commands/CommandObjectProcess.h"
30 #include "../Commands/CommandObjectQuit.h"
31 #include "../Commands/CommandObjectRegister.h"
32 #include "../Commands/CommandObjectSettings.h"
33 #include "../Commands/CommandObjectSource.h"
34 #include "../Commands/CommandObjectCommands.h"
35 #include "../Commands/CommandObjectSyntax.h"
36 #include "../Commands/CommandObjectTarget.h"
37 #include "../Commands/CommandObjectThread.h"
38 #include "../Commands/CommandObjectType.h"
39 #include "../Commands/CommandObjectVersion.h"
40 #include "../Commands/CommandObjectWatchpoint.h"
41 
42 #include "lldb/Interpreter/Args.h"
43 #include "lldb/Interpreter/Options.h"
44 #include "lldb/Core/Debugger.h"
45 #include "lldb/Core/InputReader.h"
46 #include "lldb/Core/Stream.h"
47 #include "lldb/Core/Timer.h"
48 #include "lldb/Host/Host.h"
49 #include "lldb/Target/Process.h"
50 #include "lldb/Target/Thread.h"
51 #include "lldb/Target/TargetList.h"
52 #include "lldb/Utility/CleanUp.h"
53 
54 #include "lldb/Interpreter/CommandReturnObject.h"
55 #include "lldb/Interpreter/CommandInterpreter.h"
56 #include "lldb/Interpreter/ScriptInterpreterNone.h"
57 #include "lldb/Interpreter/ScriptInterpreterPython.h"
58 
59 using namespace lldb;
60 using namespace lldb_private;
61 
62 ConstString &
63 CommandInterpreter::GetStaticBroadcasterClass ()
64 {
65     static ConstString class_name ("lldb.commandInterpreter");
66     return class_name;
67 }
68 
69 CommandInterpreter::CommandInterpreter
70 (
71     Debugger &debugger,
72     ScriptLanguage script_language,
73     bool synchronous_execution
74 ) :
75     Broadcaster (&debugger, "lldb.command-interpreter"),
76     m_debugger (debugger),
77     m_synchronous_execution (synchronous_execution),
78     m_skip_lldbinit_files (false),
79     m_skip_app_init_files (false),
80     m_script_interpreter_ap (),
81     m_comment_char ('#'),
82     m_repeat_char ('!'),
83     m_batch_command_mode (false),
84     m_truncation_warning(eNoTruncation),
85     m_command_source_depth (0)
86 {
87     const char *dbg_name = debugger.GetInstanceName().AsCString();
88     std::string lang_name = ScriptInterpreter::LanguageToString (script_language);
89     StreamString var_name;
90     var_name.Printf ("[%s].script-lang", dbg_name);
91     debugger.GetSettingsController()->SetVariable (var_name.GetData(), lang_name.c_str(),
92                                                    eVarSetOperationAssign, false,
93                                                    m_debugger.GetInstanceName().AsCString());
94     SetEventName (eBroadcastBitThreadShouldExit, "thread-should-exit");
95     SetEventName (eBroadcastBitResetPrompt, "reset-prompt");
96     SetEventName (eBroadcastBitQuitCommandReceived, "quit");
97 
98     CheckInWithManager ();
99 }
100 
101 void
102 CommandInterpreter::Initialize ()
103 {
104     Timer scoped_timer (__PRETTY_FUNCTION__, __PRETTY_FUNCTION__);
105 
106     CommandReturnObject result;
107 
108     LoadCommandDictionary ();
109 
110     // Set up some initial aliases.
111     CommandObjectSP cmd_obj_sp = GetCommandSPExact ("quit", false);
112     if (cmd_obj_sp)
113     {
114         AddAlias ("q", cmd_obj_sp);
115         AddAlias ("exit", cmd_obj_sp);
116     }
117 
118     cmd_obj_sp = GetCommandSPExact ("process attach", false);
119     if (cmd_obj_sp)
120     {
121         AddAlias ("attach", cmd_obj_sp);
122     }
123 
124     cmd_obj_sp = GetCommandSPExact ("process continue", false);
125     if (cmd_obj_sp)
126     {
127         AddAlias ("c", cmd_obj_sp);
128         AddAlias ("continue", cmd_obj_sp);
129     }
130 
131     cmd_obj_sp = GetCommandSPExact ("_regexp-break",false);
132     if (cmd_obj_sp)
133         AddAlias ("b", cmd_obj_sp);
134 
135     cmd_obj_sp = GetCommandSPExact ("thread backtrace", false);
136     if (cmd_obj_sp)
137         AddAlias ("bt", cmd_obj_sp);
138 
139     cmd_obj_sp = GetCommandSPExact ("thread step-inst", false);
140     if (cmd_obj_sp)
141     {
142         AddAlias ("stepi", cmd_obj_sp);
143         AddAlias ("si", cmd_obj_sp);
144     }
145 
146     cmd_obj_sp = GetCommandSPExact ("thread step-inst-over", false);
147     if (cmd_obj_sp)
148     {
149         AddAlias ("nexti", cmd_obj_sp);
150         AddAlias ("ni", cmd_obj_sp);
151     }
152 
153     cmd_obj_sp = GetCommandSPExact ("thread step-in", false);
154     if (cmd_obj_sp)
155     {
156         AddAlias ("s", cmd_obj_sp);
157         AddAlias ("step", cmd_obj_sp);
158     }
159 
160     cmd_obj_sp = GetCommandSPExact ("thread step-over", false);
161     if (cmd_obj_sp)
162     {
163         AddAlias ("n", cmd_obj_sp);
164         AddAlias ("next", cmd_obj_sp);
165     }
166 
167     cmd_obj_sp = GetCommandSPExact ("thread step-out", false);
168     if (cmd_obj_sp)
169     {
170         AddAlias ("finish", cmd_obj_sp);
171     }
172 
173     cmd_obj_sp = GetCommandSPExact ("frame select", false);
174     if (cmd_obj_sp)
175     {
176         AddAlias ("f", cmd_obj_sp);
177     }
178 
179     cmd_obj_sp = GetCommandSPExact ("source list", false);
180     if (cmd_obj_sp)
181     {
182         AddAlias ("l", cmd_obj_sp);
183         AddAlias ("list", cmd_obj_sp);
184     }
185 
186     cmd_obj_sp = GetCommandSPExact ("memory read", false);
187     if (cmd_obj_sp)
188         AddAlias ("x", cmd_obj_sp);
189 
190     cmd_obj_sp = GetCommandSPExact ("_regexp-up", false);
191     if (cmd_obj_sp)
192         AddAlias ("up", cmd_obj_sp);
193 
194     cmd_obj_sp = GetCommandSPExact ("_regexp-down", false);
195     if (cmd_obj_sp)
196         AddAlias ("down", cmd_obj_sp);
197 
198     cmd_obj_sp = GetCommandSPExact ("_regexp-display", false);
199     if (cmd_obj_sp)
200         AddAlias ("display", cmd_obj_sp);
201 
202     cmd_obj_sp = GetCommandSPExact ("disassemble", false);
203     if (cmd_obj_sp)
204         AddAlias ("dis", cmd_obj_sp);
205 
206     cmd_obj_sp = GetCommandSPExact ("disassemble", false);
207     if (cmd_obj_sp)
208         AddAlias ("di", cmd_obj_sp);
209 
210 
211 
212     cmd_obj_sp = GetCommandSPExact ("_regexp-undisplay", false);
213     if (cmd_obj_sp)
214         AddAlias ("undisplay", cmd_obj_sp);
215 
216     cmd_obj_sp = GetCommandSPExact ("target create", false);
217     if (cmd_obj_sp)
218         AddAlias ("file", cmd_obj_sp);
219 
220     cmd_obj_sp = GetCommandSPExact ("target modules", false);
221     if (cmd_obj_sp)
222         AddAlias ("image", cmd_obj_sp);
223 
224 
225     OptionArgVectorSP alias_arguments_vector_sp (new OptionArgVector);
226 
227     cmd_obj_sp = GetCommandSPExact ("expression", false);
228     if (cmd_obj_sp)
229     {
230         AddAlias ("expr", cmd_obj_sp);
231 
232         ProcessAliasOptionsArgs (cmd_obj_sp, "--", alias_arguments_vector_sp);
233         AddAlias ("p", cmd_obj_sp);
234         AddAlias ("print", cmd_obj_sp);
235         AddAlias ("call", cmd_obj_sp);
236         AddOrReplaceAliasOptions ("p", alias_arguments_vector_sp);
237         AddOrReplaceAliasOptions ("print", alias_arguments_vector_sp);
238         AddOrReplaceAliasOptions ("call", alias_arguments_vector_sp);
239 
240         alias_arguments_vector_sp.reset (new OptionArgVector);
241         ProcessAliasOptionsArgs (cmd_obj_sp, "-o --", alias_arguments_vector_sp);
242         AddAlias ("po", cmd_obj_sp);
243         AddOrReplaceAliasOptions ("po", alias_arguments_vector_sp);
244     }
245 
246     cmd_obj_sp = GetCommandSPExact ("process kill", false);
247     if (cmd_obj_sp)
248         AddAlias ("kill", cmd_obj_sp);
249 
250     cmd_obj_sp = GetCommandSPExact ("process launch", false);
251     if (cmd_obj_sp)
252     {
253         alias_arguments_vector_sp.reset (new OptionArgVector);
254 #if defined (__arm__)
255         ProcessAliasOptionsArgs (cmd_obj_sp, "--", alias_arguments_vector_sp);
256 #else
257         ProcessAliasOptionsArgs (cmd_obj_sp, "--shell=/bin/bash --", alias_arguments_vector_sp);
258 #endif
259         AddAlias ("r", cmd_obj_sp);
260         AddAlias ("run", cmd_obj_sp);
261         AddOrReplaceAliasOptions ("r", alias_arguments_vector_sp);
262         AddOrReplaceAliasOptions ("run", alias_arguments_vector_sp);
263     }
264 
265     cmd_obj_sp = GetCommandSPExact ("target symbols add", false);
266     if (cmd_obj_sp)
267     {
268         AddAlias ("add-dsym", cmd_obj_sp);
269     }
270 
271     cmd_obj_sp = GetCommandSPExact ("breakpoint set", false);
272     if (cmd_obj_sp)
273     {
274         alias_arguments_vector_sp.reset (new OptionArgVector);
275         ProcessAliasOptionsArgs (cmd_obj_sp, "--func-regex %1", alias_arguments_vector_sp);
276         AddAlias ("rb", cmd_obj_sp);
277         AddOrReplaceAliasOptions("rb", alias_arguments_vector_sp);
278     }
279 }
280 
281 const char *
282 CommandInterpreter::ProcessEmbeddedScriptCommands (const char *arg)
283 {
284     // This function has not yet been implemented.
285 
286     // Look for any embedded script command
287     // If found,
288     //    get interpreter object from the command dictionary,
289     //    call execute_one_command on it,
290     //    get the results as a string,
291     //    substitute that string for current stuff.
292 
293     return arg;
294 }
295 
296 
297 void
298 CommandInterpreter::LoadCommandDictionary ()
299 {
300     Timer scoped_timer (__PRETTY_FUNCTION__, __PRETTY_FUNCTION__);
301 
302     // **** IMPORTANT **** IMPORTANT *** IMPORTANT *** **** IMPORTANT **** IMPORTANT *** IMPORTANT ***
303     //
304     // Command objects that are used as cross reference objects (i.e. they inherit from CommandObjectCrossref)
305     // *MUST* be created and put into the command dictionary *BEFORE* any multi-word commands (which may use
306     // the cross-referencing stuff) are created!!!
307     //
308     // **** IMPORTANT **** IMPORTANT *** IMPORTANT *** **** IMPORTANT **** IMPORTANT *** IMPORTANT ***
309 
310 
311     // Command objects that inherit from CommandObjectCrossref must be created before other command objects
312     // are created.  This is so that when another command is created that needs to go into a crossref object,
313     // the crossref object exists and is ready to take the cross reference. Put the cross referencing command
314     // objects into the CommandDictionary now, so they are ready for use when the other commands get created.
315 
316     // Non-CommandObjectCrossref commands can now be created.
317 
318     lldb::ScriptLanguage script_language = m_debugger.GetScriptLanguage();
319 
320     m_command_dict["apropos"]   = CommandObjectSP (new CommandObjectApropos (*this));
321     m_command_dict["breakpoint"]= CommandObjectSP (new CommandObjectMultiwordBreakpoint (*this));
322     //m_command_dict["call"]      = CommandObjectSP (new CommandObjectCall (*this));
323     m_command_dict["command"]   = CommandObjectSP (new CommandObjectMultiwordCommands (*this));
324     m_command_dict["disassemble"] = CommandObjectSP (new CommandObjectDisassemble (*this));
325     m_command_dict["expression"]= CommandObjectSP (new CommandObjectExpression (*this));
326 //    m_command_dict["file"]      = CommandObjectSP (new CommandObjectFile (*this));
327     m_command_dict["frame"]     = CommandObjectSP (new CommandObjectMultiwordFrame (*this));
328     m_command_dict["help"]      = CommandObjectSP (new CommandObjectHelp (*this));
329     ///    m_command_dict["image"]     = CommandObjectSP (new CommandObjectImage (*this));
330     m_command_dict["log"]       = CommandObjectSP (new CommandObjectLog (*this));
331     m_command_dict["memory"]    = CommandObjectSP (new CommandObjectMemory (*this));
332     m_command_dict["platform"]  = CommandObjectSP (new CommandObjectPlatform (*this));
333     m_command_dict["process"]   = CommandObjectSP (new CommandObjectMultiwordProcess (*this));
334     m_command_dict["quit"]      = CommandObjectSP (new CommandObjectQuit (*this));
335     m_command_dict["register"]  = CommandObjectSP (new CommandObjectRegister (*this));
336     m_command_dict["script"]    = CommandObjectSP (new CommandObjectScript (*this, script_language));
337     m_command_dict["settings"]  = CommandObjectSP (new CommandObjectMultiwordSettings (*this));
338     m_command_dict["source"]    = CommandObjectSP (new CommandObjectMultiwordSource (*this));
339     m_command_dict["target"]    = CommandObjectSP (new CommandObjectMultiwordTarget (*this));
340     m_command_dict["thread"]    = CommandObjectSP (new CommandObjectMultiwordThread (*this));
341     m_command_dict["type"]      = CommandObjectSP (new CommandObjectType (*this));
342     m_command_dict["version"]   = CommandObjectSP (new CommandObjectVersion (*this));
343     m_command_dict["watchpoint"]= CommandObjectSP (new CommandObjectMultiwordWatchpoint (*this));
344 
345     std::auto_ptr<CommandObjectRegexCommand>
346     break_regex_cmd_ap(new CommandObjectRegexCommand (*this,
347                                                       "_regexp-break",
348                                                       "Set a breakpoint using a regular expression to specify the location.",
349                                                       "_regexp-break [<filename>:<linenum>]\n_regexp-break [<address>]\n_regexp-break <...>", 2));
350     if (break_regex_cmd_ap.get())
351     {
352         if (break_regex_cmd_ap->AddRegexCommand("^(.*[^[:space:]])[[:space:]]*:[[:space:]]*([[:digit:]]+)[[:space:]]*$", "breakpoint set --file '%1' --line %2") &&
353             break_regex_cmd_ap->AddRegexCommand("^(0x[[:xdigit:]]+)[[:space:]]*$", "breakpoint set --address %1") &&
354             break_regex_cmd_ap->AddRegexCommand("^[\"']?([-+]\\[.*\\])[\"']?[[:space:]]*$", "breakpoint set --name '%1'") &&
355             break_regex_cmd_ap->AddRegexCommand("^$", "breakpoint list --full") &&
356             break_regex_cmd_ap->AddRegexCommand("^(-.*)$", "breakpoint set %1") &&
357             break_regex_cmd_ap->AddRegexCommand("^(.*[^[:space:]])`(.*[^[:space:]])[[:space:]]*$", "breakpoint set --name '%2' --shlib '%1'") &&
358             break_regex_cmd_ap->AddRegexCommand("^(.*[^[:space:]])[[:space:]]*$", "breakpoint set --name '%1'"))
359         {
360             CommandObjectSP break_regex_cmd_sp(break_regex_cmd_ap.release());
361             m_command_dict[break_regex_cmd_sp->GetCommandName ()] = break_regex_cmd_sp;
362         }
363     }
364 
365     std::auto_ptr<CommandObjectRegexCommand>
366     down_regex_cmd_ap(new CommandObjectRegexCommand (*this,
367                                                      "_regexp-down",
368                                                      "Go down \"n\" frames in the stack (1 frame by default).",
369                                                      "_regexp-down [n]", 2));
370     if (down_regex_cmd_ap.get())
371     {
372         if (down_regex_cmd_ap->AddRegexCommand("^$", "frame select -r -1") &&
373             down_regex_cmd_ap->AddRegexCommand("^([0-9]+)$", "frame select -r -%1"))
374         {
375             CommandObjectSP down_regex_cmd_sp(down_regex_cmd_ap.release());
376             m_command_dict[down_regex_cmd_sp->GetCommandName ()] = down_regex_cmd_sp;
377         }
378     }
379 
380     std::auto_ptr<CommandObjectRegexCommand>
381     up_regex_cmd_ap(new CommandObjectRegexCommand (*this,
382                                                    "_regexp-up",
383                                                    "Go up \"n\" frames in the stack (1 frame by default).",
384                                                    "_regexp-up [n]", 2));
385     if (up_regex_cmd_ap.get())
386     {
387         if (up_regex_cmd_ap->AddRegexCommand("^$", "frame select -r 1") &&
388             up_regex_cmd_ap->AddRegexCommand("^([0-9]+)$", "frame select -r %1"))
389         {
390             CommandObjectSP up_regex_cmd_sp(up_regex_cmd_ap.release());
391             m_command_dict[up_regex_cmd_sp->GetCommandName ()] = up_regex_cmd_sp;
392         }
393     }
394 
395     std::auto_ptr<CommandObjectRegexCommand>
396     display_regex_cmd_ap(new CommandObjectRegexCommand (*this,
397                                                    "_regexp-display",
398                                                    "Add an expression evaluation stop-hook.",
399                                                    "_regexp-display expression", 2));
400     if (display_regex_cmd_ap.get())
401     {
402         if (display_regex_cmd_ap->AddRegexCommand("^(.+)$", "target stop-hook add -o \"expr -- %1\""))
403         {
404             CommandObjectSP display_regex_cmd_sp(display_regex_cmd_ap.release());
405             m_command_dict[display_regex_cmd_sp->GetCommandName ()] = display_regex_cmd_sp;
406         }
407     }
408 
409     std::auto_ptr<CommandObjectRegexCommand>
410     undisplay_regex_cmd_ap(new CommandObjectRegexCommand (*this,
411                                                    "_regexp-undisplay",
412                                                    "Remove an expression evaluation stop-hook.",
413                                                    "_regexp-undisplay stop-hook-number", 2));
414     if (undisplay_regex_cmd_ap.get())
415     {
416         if (undisplay_regex_cmd_ap->AddRegexCommand("^([0-9]+)$", "target stop-hook delete %1"))
417         {
418             CommandObjectSP undisplay_regex_cmd_sp(undisplay_regex_cmd_ap.release());
419             m_command_dict[undisplay_regex_cmd_sp->GetCommandName ()] = undisplay_regex_cmd_sp;
420         }
421     }
422 
423 }
424 
425 int
426 CommandInterpreter::GetCommandNamesMatchingPartialString (const char *cmd_str, bool include_aliases,
427                                                           StringList &matches)
428 {
429     CommandObject::AddNamesMatchingPartialString (m_command_dict, cmd_str, matches);
430 
431     if (include_aliases)
432     {
433         CommandObject::AddNamesMatchingPartialString (m_alias_dict, cmd_str, matches);
434     }
435 
436     return matches.GetSize();
437 }
438 
439 CommandObjectSP
440 CommandInterpreter::GetCommandSP (const char *cmd_cstr, bool include_aliases, bool exact, StringList *matches)
441 {
442     CommandObject::CommandMap::iterator pos;
443     CommandObjectSP ret_val;
444 
445     std::string cmd(cmd_cstr);
446 
447     if (HasCommands())
448     {
449         pos = m_command_dict.find(cmd);
450         if (pos != m_command_dict.end())
451             ret_val = pos->second;
452     }
453 
454     if (include_aliases && HasAliases())
455     {
456         pos = m_alias_dict.find(cmd);
457         if (pos != m_alias_dict.end())
458             ret_val = pos->second;
459     }
460 
461     if (HasUserCommands())
462     {
463         pos = m_user_dict.find(cmd);
464         if (pos != m_user_dict.end())
465             ret_val = pos->second;
466     }
467 
468     if (!exact && !ret_val)
469     {
470         // We will only get into here if we didn't find any exact matches.
471 
472         CommandObjectSP user_match_sp, alias_match_sp, real_match_sp;
473 
474         StringList local_matches;
475         if (matches == NULL)
476             matches = &local_matches;
477 
478         unsigned int num_cmd_matches = 0;
479         unsigned int num_alias_matches = 0;
480         unsigned int num_user_matches = 0;
481 
482         // Look through the command dictionaries one by one, and if we get only one match from any of
483         // them in toto, then return that, otherwise return an empty CommandObjectSP and the list of matches.
484 
485         if (HasCommands())
486         {
487             num_cmd_matches = CommandObject::AddNamesMatchingPartialString (m_command_dict, cmd_cstr, *matches);
488         }
489 
490         if (num_cmd_matches == 1)
491         {
492             cmd.assign(matches->GetStringAtIndex(0));
493             pos = m_command_dict.find(cmd);
494             if (pos != m_command_dict.end())
495                 real_match_sp = pos->second;
496         }
497 
498         if (include_aliases && HasAliases())
499         {
500             num_alias_matches = CommandObject::AddNamesMatchingPartialString (m_alias_dict, cmd_cstr, *matches);
501 
502         }
503 
504         if (num_alias_matches == 1)
505         {
506             cmd.assign(matches->GetStringAtIndex (num_cmd_matches));
507             pos = m_alias_dict.find(cmd);
508             if (pos != m_alias_dict.end())
509                 alias_match_sp = pos->second;
510         }
511 
512         if (HasUserCommands())
513         {
514             num_user_matches = CommandObject::AddNamesMatchingPartialString (m_user_dict, cmd_cstr, *matches);
515         }
516 
517         if (num_user_matches == 1)
518         {
519             cmd.assign (matches->GetStringAtIndex (num_cmd_matches + num_alias_matches));
520 
521             pos = m_user_dict.find (cmd);
522             if (pos != m_user_dict.end())
523                 user_match_sp = pos->second;
524         }
525 
526         // If we got exactly one match, return that, otherwise return the match list.
527 
528         if (num_user_matches + num_cmd_matches + num_alias_matches == 1)
529         {
530             if (num_cmd_matches)
531                 return real_match_sp;
532             else if (num_alias_matches)
533                 return alias_match_sp;
534             else
535                 return user_match_sp;
536         }
537     }
538     else if (matches && ret_val)
539     {
540         matches->AppendString (cmd_cstr);
541     }
542 
543 
544     return ret_val;
545 }
546 
547 bool
548 CommandInterpreter::AddCommand (const char *name, const lldb::CommandObjectSP &cmd_sp, bool can_replace)
549 {
550     if (name && name[0])
551     {
552         std::string name_sstr(name);
553         if (!can_replace)
554         {
555             if (m_command_dict.find (name_sstr) != m_command_dict.end())
556                 return false;
557         }
558         m_command_dict[name_sstr] = cmd_sp;
559         return true;
560     }
561     return false;
562 }
563 
564 bool
565 CommandInterpreter::AddUserCommand (std::string name,
566                                     const lldb::CommandObjectSP &cmd_sp,
567                                     bool can_replace)
568 {
569     if (!name.empty())
570     {
571 
572         const char* name_cstr = name.c_str();
573 
574         // do not allow replacement of internal commands
575         if (CommandExists(name_cstr))
576             return false;
577 
578         if (can_replace == false && UserCommandExists(name_cstr))
579             return false;
580 
581         m_user_dict[name] = cmd_sp;
582         return true;
583     }
584     return false;
585 }
586 
587 CommandObjectSP
588 CommandInterpreter::GetCommandSPExact (const char *cmd_cstr, bool include_aliases)
589 {
590     Args cmd_words (cmd_cstr); // Break up the command string into words, in case it's a multi-word command.
591     CommandObjectSP ret_val;   // Possibly empty return value.
592 
593     if (cmd_cstr == NULL)
594         return ret_val;
595 
596     if (cmd_words.GetArgumentCount() == 1)
597         return GetCommandSP(cmd_cstr, include_aliases, true, NULL);
598     else
599     {
600         // We have a multi-word command (seemingly), so we need to do more work.
601         // First, get the cmd_obj_sp for the first word in the command.
602         CommandObjectSP cmd_obj_sp = GetCommandSP (cmd_words.GetArgumentAtIndex (0), include_aliases, true, NULL);
603         if (cmd_obj_sp.get() != NULL)
604         {
605             // Loop through the rest of the words in the command (everything passed in was supposed to be part of a
606             // command name), and find the appropriate sub-command SP for each command word....
607             size_t end = cmd_words.GetArgumentCount();
608             for (size_t j= 1; j < end; ++j)
609             {
610                 if (cmd_obj_sp->IsMultiwordObject())
611                 {
612                     cmd_obj_sp = ((CommandObjectMultiword *) cmd_obj_sp.get())->GetSubcommandSP
613                     (cmd_words.GetArgumentAtIndex (j));
614                     if (cmd_obj_sp.get() == NULL)
615                         // The sub-command name was invalid.  Fail and return the empty 'ret_val'.
616                         return ret_val;
617                 }
618                 else
619                     // We have more words in the command name, but we don't have a multiword object. Fail and return
620                     // empty 'ret_val'.
621                     return ret_val;
622             }
623             // We successfully looped through all the command words and got valid command objects for them.  Assign the
624             // last object retrieved to 'ret_val'.
625             ret_val = cmd_obj_sp;
626         }
627     }
628     return ret_val;
629 }
630 
631 CommandObject *
632 CommandInterpreter::GetCommandObjectExact (const char *cmd_cstr, bool include_aliases)
633 {
634     return GetCommandSPExact (cmd_cstr, include_aliases).get();
635 }
636 
637 CommandObject *
638 CommandInterpreter::GetCommandObject (const char *cmd_cstr, StringList *matches)
639 {
640     CommandObject *command_obj = GetCommandSP (cmd_cstr, false, true, matches).get();
641 
642     // If we didn't find an exact match to the command string in the commands, look in
643     // the aliases.
644 
645     if (command_obj == NULL)
646     {
647         command_obj = GetCommandSP (cmd_cstr, true, true, matches).get();
648     }
649 
650     // Finally, if there wasn't an exact match among the aliases, look for an inexact match
651     // in both the commands and the aliases.
652 
653     if (command_obj == NULL)
654         command_obj = GetCommandSP(cmd_cstr, true, false, matches).get();
655 
656     return command_obj;
657 }
658 
659 bool
660 CommandInterpreter::CommandExists (const char *cmd)
661 {
662     return m_command_dict.find(cmd) != m_command_dict.end();
663 }
664 
665 bool
666 CommandInterpreter::ProcessAliasOptionsArgs (lldb::CommandObjectSP &cmd_obj_sp,
667                                             const char *options_args,
668                                             OptionArgVectorSP &option_arg_vector_sp)
669 {
670     bool success = true;
671     OptionArgVector *option_arg_vector = option_arg_vector_sp.get();
672 
673     if (!options_args || (strlen (options_args) < 1))
674         return true;
675 
676     std::string options_string (options_args);
677     Args args (options_args);
678     CommandReturnObject result;
679     // Check to see if the command being aliased can take any command options.
680     Options *options = cmd_obj_sp->GetOptions ();
681     if (options)
682     {
683         // See if any options were specified as part of the alias;  if so, handle them appropriately.
684         options->NotifyOptionParsingStarting ();
685         args.Unshift ("dummy_arg");
686         args.ParseAliasOptions (*options, result, option_arg_vector, options_string);
687         args.Shift ();
688         if (result.Succeeded())
689             options->VerifyPartialOptions (result);
690         if (!result.Succeeded() && result.GetStatus() != lldb::eReturnStatusStarted)
691         {
692             result.AppendError ("Unable to create requested alias.\n");
693             return false;
694         }
695     }
696 
697     if (!options_string.empty())
698     {
699         if (cmd_obj_sp->WantsRawCommandString ())
700             option_arg_vector->push_back (OptionArgPair ("<argument>",
701                                                           OptionArgValue (-1,
702                                                                           options_string)));
703         else
704         {
705             int argc = args.GetArgumentCount();
706             for (size_t i = 0; i < argc; ++i)
707                 if (strcmp (args.GetArgumentAtIndex (i), "") != 0)
708                     option_arg_vector->push_back
709                                 (OptionArgPair ("<argument>",
710                                                 OptionArgValue (-1,
711                                                                 std::string (args.GetArgumentAtIndex (i)))));
712         }
713     }
714 
715     return success;
716 }
717 
718 bool
719 CommandInterpreter::AliasExists (const char *cmd)
720 {
721     return m_alias_dict.find(cmd) != m_alias_dict.end();
722 }
723 
724 bool
725 CommandInterpreter::UserCommandExists (const char *cmd)
726 {
727     return m_user_dict.find(cmd) != m_user_dict.end();
728 }
729 
730 void
731 CommandInterpreter::AddAlias (const char *alias_name, CommandObjectSP& command_obj_sp)
732 {
733     command_obj_sp->SetIsAlias (true);
734     m_alias_dict[alias_name] = command_obj_sp;
735 }
736 
737 bool
738 CommandInterpreter::RemoveAlias (const char *alias_name)
739 {
740     CommandObject::CommandMap::iterator pos = m_alias_dict.find(alias_name);
741     if (pos != m_alias_dict.end())
742     {
743         m_alias_dict.erase(pos);
744         return true;
745     }
746     return false;
747 }
748 bool
749 CommandInterpreter::RemoveUser (const char *alias_name)
750 {
751     CommandObject::CommandMap::iterator pos = m_user_dict.find(alias_name);
752     if (pos != m_user_dict.end())
753     {
754         m_user_dict.erase(pos);
755         return true;
756     }
757     return false;
758 }
759 
760 void
761 CommandInterpreter::GetAliasHelp (const char *alias_name, const char *command_name, StreamString &help_string)
762 {
763     help_string.Printf ("'%s", command_name);
764     OptionArgVectorSP option_arg_vector_sp = GetAliasOptions (alias_name);
765 
766     if (option_arg_vector_sp)
767     {
768         OptionArgVector *options = option_arg_vector_sp.get();
769         for (int i = 0; i < options->size(); ++i)
770         {
771             OptionArgPair cur_option = (*options)[i];
772             std::string opt = cur_option.first;
773             OptionArgValue value_pair = cur_option.second;
774             std::string value = value_pair.second;
775             if (opt.compare("<argument>") == 0)
776             {
777                 help_string.Printf (" %s", value.c_str());
778             }
779             else
780             {
781                 help_string.Printf (" %s", opt.c_str());
782                 if ((value.compare ("<no-argument>") != 0)
783                     && (value.compare ("<need-argument") != 0))
784                 {
785                     help_string.Printf (" %s", value.c_str());
786                 }
787             }
788         }
789     }
790 
791     help_string.Printf ("'");
792 }
793 
794 size_t
795 CommandInterpreter::FindLongestCommandWord (CommandObject::CommandMap &dict)
796 {
797     CommandObject::CommandMap::const_iterator pos;
798     CommandObject::CommandMap::const_iterator end = dict.end();
799     size_t max_len = 0;
800 
801     for (pos = dict.begin(); pos != end; ++pos)
802     {
803         size_t len = pos->first.size();
804         if (max_len < len)
805             max_len = len;
806     }
807     return max_len;
808 }
809 
810 void
811 CommandInterpreter::GetHelp (CommandReturnObject &result,
812                              uint32_t cmd_types)
813 {
814     CommandObject::CommandMap::const_iterator pos;
815     uint32_t max_len = FindLongestCommandWord (m_command_dict);
816 
817     if ( (cmd_types & eCommandTypesBuiltin) == eCommandTypesBuiltin )
818     {
819 
820         result.AppendMessage("The following is a list of built-in, permanent debugger commands:");
821         result.AppendMessage("");
822 
823         for (pos = m_command_dict.begin(); pos != m_command_dict.end(); ++pos)
824         {
825             OutputFormattedHelpText (result.GetOutputStream(), pos->first.c_str(), "--", pos->second->GetHelp(),
826                                      max_len);
827         }
828         result.AppendMessage("");
829 
830     }
831 
832     if (!m_alias_dict.empty() && ( (cmd_types & eCommandTypesAliases) == eCommandTypesAliases ))
833     {
834         result.AppendMessage("The following is a list of your current command abbreviations "
835                              "(see 'help command alias' for more info):");
836         result.AppendMessage("");
837         max_len = FindLongestCommandWord (m_alias_dict);
838 
839         for (pos = m_alias_dict.begin(); pos != m_alias_dict.end(); ++pos)
840         {
841             StreamString sstr;
842             StreamString translation_and_help;
843             std::string entry_name = pos->first;
844             std::string second_entry = pos->second.get()->GetCommandName();
845             GetAliasHelp (pos->first.c_str(), pos->second->GetCommandName(), sstr);
846 
847             translation_and_help.Printf ("(%s)  %s", sstr.GetData(), pos->second->GetHelp());
848             OutputFormattedHelpText (result.GetOutputStream(), pos->first.c_str(), "--",
849                                      translation_and_help.GetData(), max_len);
850         }
851         result.AppendMessage("");
852     }
853 
854     if (!m_user_dict.empty() && ( (cmd_types & eCommandTypesUserDef) == eCommandTypesUserDef ))
855     {
856         result.AppendMessage ("The following is a list of your current user-defined commands:");
857         result.AppendMessage("");
858         max_len = FindLongestCommandWord (m_user_dict);
859         for (pos = m_user_dict.begin(); pos != m_user_dict.end(); ++pos)
860         {
861             OutputFormattedHelpText (result.GetOutputStream(), pos->first.c_str(), "--", pos->second->GetHelp(),
862                                      max_len);
863         }
864         result.AppendMessage("");
865     }
866 
867     result.AppendMessage("For more information on any particular command, try 'help <command-name>'.");
868 }
869 
870 CommandObject *
871 CommandInterpreter::GetCommandObjectForCommand (std::string &command_string)
872 {
873     // This function finds the final, lowest-level, alias-resolved command object whose 'Execute' function will
874     // eventually be invoked by the given command line.
875 
876     CommandObject *cmd_obj = NULL;
877     std::string white_space (" \t\v");
878     size_t start = command_string.find_first_not_of (white_space);
879     size_t end = 0;
880     bool done = false;
881     while (!done)
882     {
883         if (start != std::string::npos)
884         {
885             // Get the next word from command_string.
886             end = command_string.find_first_of (white_space, start);
887             if (end == std::string::npos)
888                 end = command_string.size();
889             std::string cmd_word = command_string.substr (start, end - start);
890 
891             if (cmd_obj == NULL)
892                 // Since cmd_obj is NULL we are on our first time through this loop. Check to see if cmd_word is a valid
893                 // command or alias.
894                 cmd_obj = GetCommandObject (cmd_word.c_str());
895             else if (cmd_obj->IsMultiwordObject ())
896             {
897                 // Our current object is a multi-word object; see if the cmd_word is a valid sub-command for our object.
898                 CommandObject *sub_cmd_obj =
899                                          ((CommandObjectMultiword *) cmd_obj)->GetSubcommandObject (cmd_word.c_str());
900                 if (sub_cmd_obj)
901                     cmd_obj = sub_cmd_obj;
902                 else // cmd_word was not a valid sub-command word, so we are donee
903                     done = true;
904             }
905             else
906                 // We have a cmd_obj and it is not a multi-word object, so we are done.
907                 done = true;
908 
909             // If we didn't find a valid command object, or our command object is not a multi-word object, or
910             // we are at the end of the command_string, then we are done.  Otherwise, find the start of the
911             // next word.
912 
913             if (!cmd_obj || !cmd_obj->IsMultiwordObject() || end >= command_string.size())
914                 done = true;
915             else
916                 start = command_string.find_first_not_of (white_space, end);
917         }
918         else
919             // Unable to find any more words.
920             done = true;
921     }
922 
923     if (end == command_string.size())
924         command_string.clear();
925     else
926         command_string = command_string.substr(end);
927 
928     return cmd_obj;
929 }
930 
931 static const char *k_white_space = " \t\v";
932 static const char *k_valid_command_chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_";
933 static void
934 StripLeadingSpaces (std::string &s)
935 {
936     if (!s.empty())
937     {
938         size_t pos = s.find_first_not_of (k_white_space);
939         if (pos == std::string::npos)
940             s.clear();
941         else if (pos == 0)
942             return;
943         s.erase (0, pos);
944     }
945 }
946 
947 static size_t
948 FindArgumentTerminator (const std::string &s)
949 {
950     const size_t s_len = s.size();
951     size_t offset = 0;
952     while (offset < s_len)
953     {
954         size_t pos = s.find ("--", offset);
955         if (pos == std::string::npos)
956             break;
957         if (pos > 0)
958         {
959             if (isspace(s[pos-1]))
960             {
961                 // Check if the string ends "\s--" (where \s is a space character)
962                 // or if we have "\s--\s".
963                 if ((pos + 2 >= s_len) || isspace(s[pos+2]))
964                 {
965                     return pos;
966                 }
967             }
968         }
969         offset = pos + 2;
970     }
971     return std::string::npos;
972 }
973 
974 static bool
975 ExtractCommand (std::string &command_string, std::string &command, std::string &suffix, char &quote_char)
976 {
977     command.clear();
978     suffix.clear();
979     StripLeadingSpaces (command_string);
980 
981     bool result = false;
982     quote_char = '\0';
983 
984     if (!command_string.empty())
985     {
986         const char first_char = command_string[0];
987         if (first_char == '\'' || first_char == '"')
988         {
989             quote_char = first_char;
990             const size_t end_quote_pos = command_string.find (quote_char, 1);
991             if (end_quote_pos == std::string::npos)
992             {
993                 command.swap (command_string);
994                 command_string.erase ();
995             }
996             else
997             {
998                 command.assign (command_string, 1, end_quote_pos - 1);
999                 if (end_quote_pos + 1 < command_string.size())
1000                     command_string.erase (0, command_string.find_first_not_of (k_white_space, end_quote_pos + 1));
1001                 else
1002                     command_string.erase ();
1003             }
1004         }
1005         else
1006         {
1007             const size_t first_space_pos = command_string.find_first_of (k_white_space);
1008             if (first_space_pos == std::string::npos)
1009             {
1010                 command.swap (command_string);
1011                 command_string.erase();
1012             }
1013             else
1014             {
1015                 command.assign (command_string, 0, first_space_pos);
1016                 command_string.erase(0, command_string.find_first_not_of (k_white_space, first_space_pos));
1017             }
1018         }
1019         result = true;
1020     }
1021 
1022 
1023     if (!command.empty())
1024     {
1025         // actual commands can't start with '-' or '_'
1026         if (command[0] != '-' && command[0] != '_')
1027         {
1028             size_t pos = command.find_first_not_of(k_valid_command_chars);
1029             if (pos > 0 && pos != std::string::npos)
1030             {
1031                 suffix.assign (command.begin() + pos, command.end());
1032                 command.erase (pos);
1033             }
1034         }
1035     }
1036 
1037     return result;
1038 }
1039 
1040 CommandObject *
1041 CommandInterpreter::BuildAliasResult (const char *alias_name,
1042                                       std::string &raw_input_string,
1043                                       std::string &alias_result,
1044                                       CommandReturnObject &result)
1045 {
1046     CommandObject *alias_cmd_obj = NULL;
1047     Args cmd_args (raw_input_string.c_str());
1048     alias_cmd_obj = GetCommandObject (alias_name);
1049     StreamString result_str;
1050 
1051     if (alias_cmd_obj)
1052     {
1053         std::string alias_name_str = alias_name;
1054         if ((cmd_args.GetArgumentCount() == 0)
1055             || (alias_name_str.compare (cmd_args.GetArgumentAtIndex(0)) != 0))
1056             cmd_args.Unshift (alias_name);
1057 
1058         result_str.Printf ("%s", alias_cmd_obj->GetCommandName ());
1059         OptionArgVectorSP option_arg_vector_sp = GetAliasOptions (alias_name);
1060 
1061         if (option_arg_vector_sp.get())
1062         {
1063             OptionArgVector *option_arg_vector = option_arg_vector_sp.get();
1064 
1065             for (int i = 0; i < option_arg_vector->size(); ++i)
1066             {
1067                 OptionArgPair option_pair = (*option_arg_vector)[i];
1068                 OptionArgValue value_pair = option_pair.second;
1069                 int value_type = value_pair.first;
1070                 std::string option = option_pair.first;
1071                 std::string value = value_pair.second;
1072                 if (option.compare ("<argument>") == 0)
1073                     result_str.Printf (" %s", value.c_str());
1074                 else
1075                 {
1076                     result_str.Printf (" %s", option.c_str());
1077                     if (value_type != optional_argument)
1078                         result_str.Printf (" ");
1079                     if (value.compare ("<no_argument>") != 0)
1080                     {
1081                         int index = GetOptionArgumentPosition (value.c_str());
1082                         if (index == 0)
1083                             result_str.Printf ("%s", value.c_str());
1084                         else if (index >= cmd_args.GetArgumentCount())
1085                         {
1086 
1087                             result.AppendErrorWithFormat
1088                             ("Not enough arguments provided; you need at least %d arguments to use this alias.\n",
1089                              index);
1090                             result.SetStatus (eReturnStatusFailed);
1091                             return alias_cmd_obj;
1092                         }
1093                         else
1094                         {
1095                             size_t strpos = raw_input_string.find (cmd_args.GetArgumentAtIndex (index));
1096                             if (strpos != std::string::npos)
1097                                 raw_input_string = raw_input_string.erase (strpos,
1098                                                                           strlen (cmd_args.GetArgumentAtIndex (index)));
1099                             result_str.Printf ("%s", cmd_args.GetArgumentAtIndex (index));
1100                         }
1101                     }
1102                 }
1103             }
1104         }
1105 
1106         alias_result = result_str.GetData();
1107     }
1108     return alias_cmd_obj;
1109 }
1110 
1111 Error
1112 CommandInterpreter::PreprocessCommand (std::string &command)
1113 {
1114     // The command preprocessor needs to do things to the command
1115     // line before any parsing of arguments or anything else is done.
1116     // The only current stuff that gets proprocessed is anyting enclosed
1117     // in backtick ('`') characters is evaluated as an expression and
1118     // the result of the expression must be a scalar that can be substituted
1119     // into the command. An example would be:
1120     // (lldb) memory read `$rsp + 20`
1121     Error error; // Error for any expressions that might not evaluate
1122     size_t start_backtick;
1123     size_t pos = 0;
1124     while ((start_backtick = command.find ('`', pos)) != std::string::npos)
1125     {
1126         if (start_backtick > 0 && command[start_backtick-1] == '\\')
1127         {
1128             // The backtick was preceeded by a '\' character, remove the slash
1129             // and don't treat the backtick as the start of an expression
1130             command.erase(start_backtick-1, 1);
1131             // No need to add one to start_backtick since we just deleted a char
1132             pos = start_backtick;
1133         }
1134         else
1135         {
1136             const size_t expr_content_start = start_backtick + 1;
1137             const size_t end_backtick = command.find ('`', expr_content_start);
1138             if (end_backtick == std::string::npos)
1139                 return error;
1140             else if (end_backtick == expr_content_start)
1141             {
1142                 // Empty expression (two backticks in a row)
1143                 command.erase (start_backtick, 2);
1144             }
1145             else
1146             {
1147                 std::string expr_str (command, expr_content_start, end_backtick - expr_content_start);
1148 
1149                 ExecutionContext exe_ctx(GetExecutionContext());
1150                 Target *target = exe_ctx.GetTargetPtr();
1151                 // Get a dummy target to allow for calculator mode while processing backticks.
1152                 // This also helps break the infinite loop caused when target is null.
1153                 if (!target)
1154                     target = Host::GetDummyTarget(GetDebugger()).get();
1155                 if (target)
1156                 {
1157                     const bool coerce_to_id = false;
1158                     const bool unwind_on_error = true;
1159                     const bool keep_in_memory = false;
1160                     ValueObjectSP expr_result_valobj_sp;
1161                     ExecutionResults expr_result = target->EvaluateExpression (expr_str.c_str(),
1162                                                                                exe_ctx.GetFramePtr(),
1163                                                                                eExecutionPolicyOnlyWhenNeeded,
1164                                                                                coerce_to_id,
1165                                                                                unwind_on_error,
1166                                                                                keep_in_memory,
1167                                                                                eNoDynamicValues,
1168                                                                                expr_result_valobj_sp,
1169                                                                                0 /* no timeout */);
1170                     if (expr_result == eExecutionCompleted)
1171                     {
1172                         Scalar scalar;
1173                         if (expr_result_valobj_sp->ResolveValue (scalar))
1174                         {
1175                             command.erase (start_backtick, end_backtick - start_backtick + 1);
1176                             StreamString value_strm;
1177                             const bool show_type = false;
1178                             scalar.GetValue (&value_strm, show_type);
1179                             size_t value_string_size = value_strm.GetSize();
1180                             if (value_string_size)
1181                             {
1182                                 command.insert (start_backtick, value_strm.GetData(), value_string_size);
1183                                 pos = start_backtick + value_string_size;
1184                                 continue;
1185                             }
1186                             else
1187                             {
1188                                 error.SetErrorStringWithFormat("expression value didn't result in a scalar value for the expression '%s'", expr_str.c_str());
1189                             }
1190                         }
1191                         else
1192                         {
1193                             error.SetErrorStringWithFormat("expression value didn't result in a scalar value for the expression '%s'", expr_str.c_str());
1194                         }
1195                     }
1196                     else
1197                     {
1198                         if (expr_result_valobj_sp)
1199                             error = expr_result_valobj_sp->GetError();
1200                         if (error.Success())
1201                         {
1202 
1203                             switch (expr_result)
1204                             {
1205                                 case eExecutionSetupError:
1206                                     error.SetErrorStringWithFormat("expression setup error for the expression '%s'", expr_str.c_str());
1207                                     break;
1208                                 case eExecutionCompleted:
1209                                     break;
1210                                 case eExecutionDiscarded:
1211                                     error.SetErrorStringWithFormat("expression discarded for the expression '%s'", expr_str.c_str());
1212                                     break;
1213                                 case eExecutionInterrupted:
1214                                     error.SetErrorStringWithFormat("expression interrupted for the expression '%s'", expr_str.c_str());
1215                                     break;
1216                                 case eExecutionTimedOut:
1217                                     error.SetErrorStringWithFormat("expression timed out for the expression '%s'", expr_str.c_str());
1218                                     break;
1219                             }
1220                         }
1221                     }
1222                 }
1223             }
1224             if (error.Fail())
1225                 break;
1226         }
1227     }
1228     return error;
1229 }
1230 
1231 
1232 bool
1233 CommandInterpreter::HandleCommand (const char *command_line,
1234                                    LazyBool lazy_add_to_history,
1235                                    CommandReturnObject &result,
1236                                    ExecutionContext *override_context,
1237                                    bool repeat_on_empty_command,
1238                                    bool no_context_switching)
1239 
1240 {
1241 
1242     bool done = false;
1243     CommandObject *cmd_obj = NULL;
1244     bool wants_raw_input = false;
1245     std::string command_string (command_line);
1246     std::string original_command_string (command_line);
1247 
1248     LogSP log (lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_COMMANDS));
1249     Host::SetCrashDescriptionWithFormat ("HandleCommand(command = \"%s\")", command_line);
1250 
1251     // Make a scoped cleanup object that will clear the crash description string
1252     // on exit of this function.
1253     lldb_utility::CleanUp <const char *> crash_description_cleanup(NULL, Host::SetCrashDescription);
1254 
1255     if (log)
1256         log->Printf ("Processing command: %s", command_line);
1257 
1258     Timer scoped_timer (__PRETTY_FUNCTION__, "Handling command: %s.", command_line);
1259 
1260     if (!no_context_switching)
1261         UpdateExecutionContext (override_context);
1262 
1263     // <rdar://problem/11328896>
1264     bool add_to_history;
1265     if (lazy_add_to_history == eLazyBoolCalculate)
1266         add_to_history = (m_command_source_depth == 0);
1267     else
1268         add_to_history = (lazy_add_to_history == eLazyBoolYes);
1269 
1270     bool empty_command = false;
1271     bool comment_command = false;
1272     if (command_string.empty())
1273         empty_command = true;
1274     else
1275     {
1276         const char *k_space_characters = "\t\n\v\f\r ";
1277 
1278         size_t non_space = command_string.find_first_not_of (k_space_characters);
1279         // Check for empty line or comment line (lines whose first
1280         // non-space character is the comment character for this interpreter)
1281         if (non_space == std::string::npos)
1282             empty_command = true;
1283         else if (command_string[non_space] == m_comment_char)
1284              comment_command = true;
1285         else if (command_string[non_space] == m_repeat_char)
1286         {
1287             const char *history_string = FindHistoryString (command_string.c_str() + non_space);
1288             if (history_string == NULL)
1289             {
1290                 result.AppendErrorWithFormat ("Could not find entry: %s in history", command_string.c_str());
1291                 result.SetStatus(eReturnStatusFailed);
1292                 return false;
1293             }
1294             add_to_history = false;
1295             command_string = history_string;
1296             original_command_string = history_string;
1297         }
1298     }
1299 
1300     if (empty_command)
1301     {
1302         if (repeat_on_empty_command)
1303         {
1304             if (m_command_history.empty())
1305             {
1306                 result.AppendError ("empty command");
1307                 result.SetStatus(eReturnStatusFailed);
1308                 return false;
1309             }
1310             else
1311             {
1312                 command_line = m_repeat_command.c_str();
1313                 command_string = command_line;
1314                 original_command_string = command_line;
1315                 if (m_repeat_command.empty())
1316                 {
1317                     result.AppendErrorWithFormat("No auto repeat.\n");
1318                     result.SetStatus (eReturnStatusFailed);
1319                     return false;
1320                 }
1321             }
1322             add_to_history = false;
1323         }
1324         else
1325         {
1326             result.SetStatus (eReturnStatusSuccessFinishNoResult);
1327             return true;
1328         }
1329     }
1330     else if (comment_command)
1331     {
1332         result.SetStatus (eReturnStatusSuccessFinishNoResult);
1333         return true;
1334     }
1335 
1336 
1337     Error error (PreprocessCommand (command_string));
1338 
1339     if (error.Fail())
1340     {
1341         result.AppendError (error.AsCString());
1342         result.SetStatus(eReturnStatusFailed);
1343         return false;
1344     }
1345     // Phase 1.
1346 
1347     // Before we do ANY kind of argument processing, etc. we need to figure out what the real/final command object
1348     // is for the specified command, and whether or not it wants raw input.  This gets complicated by the fact that
1349     // the user could have specified an alias, and in translating the alias there may also be command options and/or
1350     // even data (including raw text strings) that need to be found and inserted into the command line as part of
1351     // the translation.  So this first step is plain look-up & replacement, resulting in three things:  1). the command
1352     // object whose Execute method will actually be called; 2). a revised command string, with all substitutions &
1353     // replacements taken care of; 3). whether or not the Execute function wants raw input or not.
1354 
1355     StreamString revised_command_line;
1356     size_t actual_cmd_name_len = 0;
1357     std::string next_word;
1358     StringList matches;
1359     while (!done)
1360     {
1361         char quote_char = '\0';
1362         std::string suffix;
1363         ExtractCommand (command_string, next_word, suffix, quote_char);
1364         if (cmd_obj == NULL)
1365         {
1366             if (AliasExists (next_word.c_str()))
1367             {
1368                 std::string alias_result;
1369                 cmd_obj = BuildAliasResult (next_word.c_str(), command_string, alias_result, result);
1370                 revised_command_line.Printf ("%s", alias_result.c_str());
1371                 if (cmd_obj)
1372                 {
1373                     wants_raw_input = cmd_obj->WantsRawCommandString ();
1374                     actual_cmd_name_len = strlen (cmd_obj->GetCommandName());
1375                 }
1376             }
1377             else
1378             {
1379                 cmd_obj = GetCommandObject (next_word.c_str(), &matches);
1380                 if (cmd_obj)
1381                 {
1382                     actual_cmd_name_len += next_word.length();
1383                     revised_command_line.Printf ("%s", next_word.c_str());
1384                     wants_raw_input = cmd_obj->WantsRawCommandString ();
1385                 }
1386                 else
1387                 {
1388                     revised_command_line.Printf ("%s", next_word.c_str());
1389                 }
1390             }
1391         }
1392         else
1393         {
1394             if (cmd_obj->IsMultiwordObject ())
1395             {
1396                 CommandObject *sub_cmd_obj = ((CommandObjectMultiword *) cmd_obj)->GetSubcommandObject (next_word.c_str());
1397                 if (sub_cmd_obj)
1398                 {
1399                     actual_cmd_name_len += next_word.length() + 1;
1400                     revised_command_line.Printf (" %s", next_word.c_str());
1401                     cmd_obj = sub_cmd_obj;
1402                     wants_raw_input = cmd_obj->WantsRawCommandString ();
1403                 }
1404                 else
1405                 {
1406                     if (quote_char)
1407                         revised_command_line.Printf (" %c%s%s%c", quote_char, next_word.c_str(), suffix.c_str(), quote_char);
1408                     else
1409                         revised_command_line.Printf (" %s%s", next_word.c_str(), suffix.c_str());
1410                     done = true;
1411                 }
1412             }
1413             else
1414             {
1415                 if (quote_char)
1416                     revised_command_line.Printf (" %c%s%s%c", quote_char, next_word.c_str(), suffix.c_str(), quote_char);
1417                 else
1418                     revised_command_line.Printf (" %s%s", next_word.c_str(), suffix.c_str());
1419                 done = true;
1420             }
1421         }
1422 
1423         if (cmd_obj == NULL)
1424         {
1425             uint32_t num_matches = matches.GetSize();
1426             if (matches.GetSize() > 1) {
1427                 std::string error_msg;
1428                 error_msg.assign ("Ambiguous command '");
1429                 error_msg.append(next_word.c_str());
1430                 error_msg.append ("'.");
1431 
1432                 error_msg.append (" Possible matches:");
1433 
1434                 for (uint32_t i = 0; i < num_matches; ++i) {
1435                     error_msg.append ("\n\t");
1436                     error_msg.append (matches.GetStringAtIndex(i));
1437                 }
1438                 error_msg.append ("\n");
1439                 result.AppendRawError (error_msg.c_str(), error_msg.size());
1440             } else {
1441                 // We didn't have only one match, otherwise we wouldn't get here.
1442                 assert(num_matches == 0);
1443                 result.AppendErrorWithFormat ("'%s' is not a valid command.\n", next_word.c_str());
1444             }
1445             result.SetStatus (eReturnStatusFailed);
1446             return false;
1447         }
1448 
1449         if (cmd_obj->IsMultiwordObject ())
1450         {
1451             if (!suffix.empty())
1452             {
1453 
1454                 result.AppendErrorWithFormat ("multi-word commands ('%s') can't have shorthand suffixes: '%s'\n",
1455                                               next_word.c_str(),
1456                                               suffix.c_str());
1457                 result.SetStatus (eReturnStatusFailed);
1458                 return false;
1459             }
1460         }
1461         else
1462         {
1463             // If we found a normal command, we are done
1464             done = true;
1465             if (!suffix.empty())
1466             {
1467                 switch (suffix[0])
1468                 {
1469                 case '/':
1470                     // GDB format suffixes
1471                     {
1472                         Options *command_options = cmd_obj->GetOptions();
1473                         if (command_options && command_options->SupportsLongOption("gdb-format"))
1474                         {
1475                             std::string gdb_format_option ("--gdb-format=");
1476                             gdb_format_option += (suffix.c_str() + 1);
1477 
1478                             bool inserted = false;
1479                             std::string &cmd = revised_command_line.GetString();
1480                             size_t arg_terminator_idx = FindArgumentTerminator (cmd);
1481                             if (arg_terminator_idx != std::string::npos)
1482                             {
1483                                 // Insert the gdb format option before the "--" that terminates options
1484                                 gdb_format_option.append(1,' ');
1485                                 cmd.insert(arg_terminator_idx, gdb_format_option);
1486                                 inserted = true;
1487                             }
1488 
1489                             if (!inserted)
1490                                 revised_command_line.Printf (" %s", gdb_format_option.c_str());
1491 
1492                             if (wants_raw_input && FindArgumentTerminator(cmd) == std::string::npos)
1493                                 revised_command_line.PutCString (" --");
1494                         }
1495                         else
1496                         {
1497                             result.AppendErrorWithFormat ("the '%s' command doesn't support the --gdb-format option\n",
1498                                                           cmd_obj->GetCommandName());
1499                             result.SetStatus (eReturnStatusFailed);
1500                             return false;
1501                         }
1502                     }
1503                     break;
1504 
1505                 default:
1506                     result.AppendErrorWithFormat ("unknown command shorthand suffix: '%s'\n",
1507                                                   suffix.c_str());
1508                     result.SetStatus (eReturnStatusFailed);
1509                     return false;
1510 
1511                 }
1512             }
1513         }
1514         if (command_string.length() == 0)
1515             done = true;
1516 
1517     }
1518 
1519     if (!command_string.empty())
1520         revised_command_line.Printf (" %s", command_string.c_str());
1521 
1522     // End of Phase 1.
1523     // At this point cmd_obj should contain the CommandObject whose Execute method will be called, if the command
1524     // specified was valid; revised_command_line contains the complete command line (including command name(s)),
1525     // fully translated with all substitutions & translations taken care of (still in raw text format); and
1526     // wants_raw_input specifies whether the Execute method expects raw input or not.
1527 
1528 
1529     if (log)
1530     {
1531         log->Printf ("HandleCommand, cmd_obj : '%s'", cmd_obj ? cmd_obj->GetCommandName() : "<not found>");
1532         log->Printf ("HandleCommand, revised_command_line: '%s'", revised_command_line.GetData());
1533         log->Printf ("HandleCommand, wants_raw_input:'%s'", wants_raw_input ? "True" : "False");
1534     }
1535 
1536     // Phase 2.
1537     // Take care of things like setting up the history command & calling the appropriate Execute method on the
1538     // CommandObject, with the appropriate arguments.
1539 
1540     if (cmd_obj != NULL)
1541     {
1542         if (add_to_history)
1543         {
1544             Args command_args (revised_command_line.GetData());
1545             const char *repeat_command = cmd_obj->GetRepeatCommand(command_args, 0);
1546             if (repeat_command != NULL)
1547                 m_repeat_command.assign(repeat_command);
1548             else
1549                 m_repeat_command.assign(original_command_string.c_str());
1550 
1551             // Don't keep pushing the same command onto the history...
1552             if (m_command_history.empty() || m_command_history.back() != original_command_string)
1553                 m_command_history.push_back (original_command_string);
1554         }
1555 
1556         command_string = revised_command_line.GetData();
1557         std::string command_name (cmd_obj->GetCommandName());
1558         std::string remainder;
1559         if (actual_cmd_name_len < command_string.length())
1560             remainder = command_string.substr (actual_cmd_name_len);  // Note: 'actual_cmd_name_len' may be considerably shorter
1561                                                            // than cmd_obj->GetCommandName(), because name completion
1562                                                            // allows users to enter short versions of the names,
1563                                                            // e.g. 'br s' for 'breakpoint set'.
1564 
1565         // Remove any initial spaces
1566         std::string white_space (" \t\v");
1567         size_t pos = remainder.find_first_not_of (white_space);
1568         if (pos != 0 && pos != std::string::npos)
1569             remainder.erase(0, pos);
1570 
1571         if (log)
1572             log->Printf ("HandleCommand, command line after removing command name(s): '%s'", remainder.c_str());
1573 
1574         cmd_obj->Execute (remainder.c_str(), result);
1575     }
1576     else
1577     {
1578         // We didn't find the first command object, so complete the first argument.
1579         Args command_args (revised_command_line.GetData());
1580         StringList matches;
1581         int num_matches;
1582         int cursor_index = 0;
1583         int cursor_char_position = strlen (command_args.GetArgumentAtIndex(0));
1584         bool word_complete;
1585         num_matches = HandleCompletionMatches (command_args,
1586                                                cursor_index,
1587                                                cursor_char_position,
1588                                                0,
1589                                                -1,
1590                                                word_complete,
1591                                                matches);
1592 
1593         if (num_matches > 0)
1594         {
1595             std::string error_msg;
1596             error_msg.assign ("ambiguous command '");
1597             error_msg.append(command_args.GetArgumentAtIndex(0));
1598             error_msg.append ("'.");
1599 
1600             error_msg.append (" Possible completions:");
1601             for (int i = 0; i < num_matches; i++)
1602             {
1603                 error_msg.append ("\n\t");
1604                 error_msg.append (matches.GetStringAtIndex (i));
1605             }
1606             error_msg.append ("\n");
1607             result.AppendRawError (error_msg.c_str(), error_msg.size());
1608         }
1609         else
1610             result.AppendErrorWithFormat ("Unrecognized command '%s'.\n", command_args.GetArgumentAtIndex (0));
1611 
1612         result.SetStatus (eReturnStatusFailed);
1613     }
1614 
1615     if (log)
1616       log->Printf ("HandleCommand, command %s", (result.Succeeded() ? "succeeded" : "did not succeed"));
1617 
1618     return result.Succeeded();
1619 }
1620 
1621 int
1622 CommandInterpreter::HandleCompletionMatches (Args &parsed_line,
1623                                              int &cursor_index,
1624                                              int &cursor_char_position,
1625                                              int match_start_point,
1626                                              int max_return_elements,
1627                                              bool &word_complete,
1628                                              StringList &matches)
1629 {
1630     int num_command_matches = 0;
1631     bool look_for_subcommand = false;
1632 
1633     // For any of the command completions a unique match will be a complete word.
1634     word_complete = true;
1635 
1636     if (cursor_index == -1)
1637     {
1638         // We got nothing on the command line, so return the list of commands
1639         bool include_aliases = true;
1640         num_command_matches = GetCommandNamesMatchingPartialString ("", include_aliases, matches);
1641     }
1642     else if (cursor_index == 0)
1643     {
1644         // The cursor is in the first argument, so just do a lookup in the dictionary.
1645         CommandObject *cmd_obj = GetCommandObject (parsed_line.GetArgumentAtIndex(0), &matches);
1646         num_command_matches = matches.GetSize();
1647 
1648         if (num_command_matches == 1
1649             && cmd_obj && cmd_obj->IsMultiwordObject()
1650             && matches.GetStringAtIndex(0) != NULL
1651             && strcmp (parsed_line.GetArgumentAtIndex(0), matches.GetStringAtIndex(0)) == 0)
1652         {
1653             look_for_subcommand = true;
1654             num_command_matches = 0;
1655             matches.DeleteStringAtIndex(0);
1656             parsed_line.AppendArgument ("");
1657             cursor_index++;
1658             cursor_char_position = 0;
1659         }
1660     }
1661 
1662     if (cursor_index > 0 || look_for_subcommand)
1663     {
1664         // We are completing further on into a commands arguments, so find the command and tell it
1665         // to complete the command.
1666         // First see if there is a matching initial command:
1667         CommandObject *command_object = GetCommandObject (parsed_line.GetArgumentAtIndex(0));
1668         if (command_object == NULL)
1669         {
1670             return 0;
1671         }
1672         else
1673         {
1674             parsed_line.Shift();
1675             cursor_index--;
1676             num_command_matches = command_object->HandleCompletion (parsed_line,
1677                                                                     cursor_index,
1678                                                                     cursor_char_position,
1679                                                                     match_start_point,
1680                                                                     max_return_elements,
1681                                                                     word_complete,
1682                                                                     matches);
1683         }
1684     }
1685 
1686     return num_command_matches;
1687 
1688 }
1689 
1690 int
1691 CommandInterpreter::HandleCompletion (const char *current_line,
1692                                       const char *cursor,
1693                                       const char *last_char,
1694                                       int match_start_point,
1695                                       int max_return_elements,
1696                                       StringList &matches)
1697 {
1698     // We parse the argument up to the cursor, so the last argument in parsed_line is
1699     // the one containing the cursor, and the cursor is after the last character.
1700 
1701     Args parsed_line(current_line, last_char - current_line);
1702     Args partial_parsed_line(current_line, cursor - current_line);
1703 
1704     // Don't complete comments, and if the line we are completing is just the history repeat character,
1705     // substitute the appropriate history line.
1706     const char *first_arg = parsed_line.GetArgumentAtIndex(0);
1707     if (first_arg)
1708     {
1709         if (first_arg[0] == m_comment_char)
1710             return 0;
1711         else if (first_arg[0] == m_repeat_char)
1712         {
1713             const char *history_string = FindHistoryString (first_arg);
1714             if (history_string != NULL)
1715             {
1716                 matches.Clear();
1717                 matches.InsertStringAtIndex(0, history_string);
1718                 return -2;
1719             }
1720             else
1721                 return 0;
1722 
1723         }
1724     }
1725 
1726 
1727     int num_args = partial_parsed_line.GetArgumentCount();
1728     int cursor_index = partial_parsed_line.GetArgumentCount() - 1;
1729     int cursor_char_position;
1730 
1731     if (cursor_index == -1)
1732         cursor_char_position = 0;
1733     else
1734         cursor_char_position = strlen (partial_parsed_line.GetArgumentAtIndex(cursor_index));
1735 
1736     if (cursor > current_line && cursor[-1] == ' ')
1737     {
1738         // We are just after a space.  If we are in an argument, then we will continue
1739         // parsing, but if we are between arguments, then we have to complete whatever the next
1740         // element would be.
1741         // We can distinguish the two cases because if we are in an argument (e.g. because the space is
1742         // protected by a quote) then the space will also be in the parsed argument...
1743 
1744         const char *current_elem = partial_parsed_line.GetArgumentAtIndex(cursor_index);
1745         if (cursor_char_position == 0 || current_elem[cursor_char_position - 1] != ' ')
1746         {
1747             parsed_line.InsertArgumentAtIndex(cursor_index + 1, "", '"');
1748             cursor_index++;
1749             cursor_char_position = 0;
1750         }
1751     }
1752 
1753     int num_command_matches;
1754 
1755     matches.Clear();
1756 
1757     // Only max_return_elements == -1 is supported at present:
1758     assert (max_return_elements == -1);
1759     bool word_complete;
1760     num_command_matches = HandleCompletionMatches (parsed_line,
1761                                                    cursor_index,
1762                                                    cursor_char_position,
1763                                                    match_start_point,
1764                                                    max_return_elements,
1765                                                    word_complete,
1766                                                    matches);
1767 
1768     if (num_command_matches <= 0)
1769             return num_command_matches;
1770 
1771     if (num_args == 0)
1772     {
1773         // If we got an empty string, insert nothing.
1774         matches.InsertStringAtIndex(0, "");
1775     }
1776     else
1777     {
1778         // Now figure out if there is a common substring, and if so put that in element 0, otherwise
1779         // put an empty string in element 0.
1780         std::string command_partial_str;
1781         if (cursor_index >= 0)
1782             command_partial_str.assign(parsed_line.GetArgumentAtIndex(cursor_index),
1783                                        parsed_line.GetArgumentAtIndex(cursor_index) + cursor_char_position);
1784 
1785         std::string common_prefix;
1786         matches.LongestCommonPrefix (common_prefix);
1787         int partial_name_len = command_partial_str.size();
1788 
1789         // If we matched a unique single command, add a space...
1790         // Only do this if the completer told us this was a complete word, however...
1791         if (num_command_matches == 1 && word_complete)
1792         {
1793             char quote_char = parsed_line.GetArgumentQuoteCharAtIndex(cursor_index);
1794             if (quote_char != '\0')
1795                 common_prefix.push_back(quote_char);
1796 
1797             common_prefix.push_back(' ');
1798         }
1799         common_prefix.erase (0, partial_name_len);
1800         matches.InsertStringAtIndex(0, common_prefix.c_str());
1801     }
1802     return num_command_matches;
1803 }
1804 
1805 
1806 CommandInterpreter::~CommandInterpreter ()
1807 {
1808 }
1809 
1810 const char *
1811 CommandInterpreter::GetPrompt ()
1812 {
1813     return m_debugger.GetPrompt();
1814 }
1815 
1816 void
1817 CommandInterpreter::SetPrompt (const char *new_prompt)
1818 {
1819     m_debugger.SetPrompt (new_prompt);
1820 }
1821 
1822 size_t
1823 CommandInterpreter::GetConfirmationInputReaderCallback
1824 (
1825     void *baton,
1826     InputReader &reader,
1827     lldb::InputReaderAction action,
1828     const char *bytes,
1829     size_t bytes_len
1830 )
1831 {
1832     File &out_file = reader.GetDebugger().GetOutputFile();
1833     bool *response_ptr = (bool *) baton;
1834 
1835     switch (action)
1836     {
1837     case eInputReaderActivate:
1838         if (out_file.IsValid())
1839         {
1840             if (reader.GetPrompt())
1841             {
1842                 out_file.Printf ("%s", reader.GetPrompt());
1843                 out_file.Flush ();
1844             }
1845         }
1846         break;
1847 
1848     case eInputReaderDeactivate:
1849         break;
1850 
1851     case eInputReaderReactivate:
1852         if (out_file.IsValid() && reader.GetPrompt())
1853         {
1854             out_file.Printf ("%s", reader.GetPrompt());
1855             out_file.Flush ();
1856         }
1857         break;
1858 
1859     case eInputReaderAsynchronousOutputWritten:
1860         break;
1861 
1862     case eInputReaderGotToken:
1863         if (bytes_len == 0)
1864         {
1865             reader.SetIsDone(true);
1866         }
1867         else if (bytes[0] == 'y' || bytes[0] == 'Y')
1868         {
1869             *response_ptr = true;
1870             reader.SetIsDone(true);
1871         }
1872         else if (bytes[0] == 'n' || bytes[0] == 'N')
1873         {
1874             *response_ptr = false;
1875             reader.SetIsDone(true);
1876         }
1877         else
1878         {
1879             if (out_file.IsValid() && !reader.IsDone() && reader.GetPrompt())
1880             {
1881                 out_file.Printf ("Please answer \"y\" or \"n\".\n%s", reader.GetPrompt());
1882                 out_file.Flush ();
1883             }
1884         }
1885         break;
1886 
1887     case eInputReaderInterrupt:
1888     case eInputReaderEndOfFile:
1889         *response_ptr = false;  // Assume ^C or ^D means cancel the proposed action
1890         reader.SetIsDone (true);
1891         break;
1892 
1893     case eInputReaderDone:
1894         break;
1895     }
1896 
1897     return bytes_len;
1898 
1899 }
1900 
1901 bool
1902 CommandInterpreter::Confirm (const char *message, bool default_answer)
1903 {
1904     // Check AutoConfirm first:
1905     if (m_debugger.GetAutoConfirm())
1906         return default_answer;
1907 
1908     InputReaderSP reader_sp (new InputReader(GetDebugger()));
1909     bool response = default_answer;
1910     if (reader_sp)
1911     {
1912         std::string prompt(message);
1913         prompt.append(": [");
1914         if (default_answer)
1915             prompt.append ("Y/n] ");
1916         else
1917             prompt.append ("y/N] ");
1918 
1919         Error err (reader_sp->Initialize (CommandInterpreter::GetConfirmationInputReaderCallback,
1920                                           &response,                    // baton
1921                                           eInputReaderGranularityLine,  // token size, to pass to callback function
1922                                           NULL,                         // end token
1923                                           prompt.c_str(),               // prompt
1924                                           true));                       // echo input
1925         if (err.Success())
1926         {
1927             GetDebugger().PushInputReader (reader_sp);
1928         }
1929         reader_sp->WaitOnReaderIsDone();
1930     }
1931     return response;
1932 }
1933 
1934 
1935 void
1936 CommandInterpreter::CrossRegisterCommand (const char * dest_cmd, const char * object_type)
1937 {
1938     CommandObjectSP cmd_obj_sp = GetCommandSPExact (dest_cmd, true);
1939 
1940     if (cmd_obj_sp)
1941     {
1942         CommandObject *cmd_obj = cmd_obj_sp.get();
1943         if (cmd_obj->IsCrossRefObject ())
1944             cmd_obj->AddObject (object_type);
1945     }
1946 }
1947 
1948 OptionArgVectorSP
1949 CommandInterpreter::GetAliasOptions (const char *alias_name)
1950 {
1951     OptionArgMap::iterator pos;
1952     OptionArgVectorSP ret_val;
1953 
1954     std::string alias (alias_name);
1955 
1956     if (HasAliasOptions())
1957     {
1958         pos = m_alias_options.find (alias);
1959         if (pos != m_alias_options.end())
1960           ret_val = pos->second;
1961     }
1962 
1963     return ret_val;
1964 }
1965 
1966 void
1967 CommandInterpreter::RemoveAliasOptions (const char *alias_name)
1968 {
1969     OptionArgMap::iterator pos = m_alias_options.find(alias_name);
1970     if (pos != m_alias_options.end())
1971     {
1972         m_alias_options.erase (pos);
1973     }
1974 }
1975 
1976 void
1977 CommandInterpreter::AddOrReplaceAliasOptions (const char *alias_name, OptionArgVectorSP &option_arg_vector_sp)
1978 {
1979     m_alias_options[alias_name] = option_arg_vector_sp;
1980 }
1981 
1982 bool
1983 CommandInterpreter::HasCommands ()
1984 {
1985     return (!m_command_dict.empty());
1986 }
1987 
1988 bool
1989 CommandInterpreter::HasAliases ()
1990 {
1991     return (!m_alias_dict.empty());
1992 }
1993 
1994 bool
1995 CommandInterpreter::HasUserCommands ()
1996 {
1997     return (!m_user_dict.empty());
1998 }
1999 
2000 bool
2001 CommandInterpreter::HasAliasOptions ()
2002 {
2003     return (!m_alias_options.empty());
2004 }
2005 
2006 void
2007 CommandInterpreter::BuildAliasCommandArgs (CommandObject *alias_cmd_obj,
2008                                            const char *alias_name,
2009                                            Args &cmd_args,
2010                                            std::string &raw_input_string,
2011                                            CommandReturnObject &result)
2012 {
2013     OptionArgVectorSP option_arg_vector_sp = GetAliasOptions (alias_name);
2014 
2015     bool wants_raw_input = alias_cmd_obj->WantsRawCommandString();
2016 
2017     // Make sure that the alias name is the 0th element in cmd_args
2018     std::string alias_name_str = alias_name;
2019     if (alias_name_str.compare (cmd_args.GetArgumentAtIndex(0)) != 0)
2020         cmd_args.Unshift (alias_name);
2021 
2022     Args new_args (alias_cmd_obj->GetCommandName());
2023     if (new_args.GetArgumentCount() == 2)
2024         new_args.Shift();
2025 
2026     if (option_arg_vector_sp.get())
2027     {
2028         if (wants_raw_input)
2029         {
2030             // We have a command that both has command options and takes raw input.  Make *sure* it has a
2031             // " -- " in the right place in the raw_input_string.
2032             size_t pos = raw_input_string.find(" -- ");
2033             if (pos == std::string::npos)
2034             {
2035                 // None found; assume it goes at the beginning of the raw input string
2036                 raw_input_string.insert (0, " -- ");
2037             }
2038         }
2039 
2040         OptionArgVector *option_arg_vector = option_arg_vector_sp.get();
2041         int old_size = cmd_args.GetArgumentCount();
2042         std::vector<bool> used (old_size + 1, false);
2043 
2044         used[0] = true;
2045 
2046         for (int i = 0; i < option_arg_vector->size(); ++i)
2047         {
2048             OptionArgPair option_pair = (*option_arg_vector)[i];
2049             OptionArgValue value_pair = option_pair.second;
2050             int value_type = value_pair.first;
2051             std::string option = option_pair.first;
2052             std::string value = value_pair.second;
2053             if (option.compare ("<argument>") == 0)
2054             {
2055                 if (!wants_raw_input
2056                     || (value.compare("--") != 0)) // Since we inserted this above, make sure we don't insert it twice
2057                     new_args.AppendArgument (value.c_str());
2058             }
2059             else
2060             {
2061                 if (value_type != optional_argument)
2062                     new_args.AppendArgument (option.c_str());
2063                 if (value.compare ("<no-argument>") != 0)
2064                 {
2065                     int index = GetOptionArgumentPosition (value.c_str());
2066                     if (index == 0)
2067                     {
2068                         // value was NOT a positional argument; must be a real value
2069                         if (value_type != optional_argument)
2070                             new_args.AppendArgument (value.c_str());
2071                         else
2072                         {
2073                             char buffer[255];
2074                             ::snprintf (buffer, sizeof (buffer), "%s%s", option.c_str(), value.c_str());
2075                             new_args.AppendArgument (buffer);
2076                         }
2077 
2078                     }
2079                     else if (index >= cmd_args.GetArgumentCount())
2080                     {
2081                         result.AppendErrorWithFormat
2082                                     ("Not enough arguments provided; you need at least %d arguments to use this alias.\n",
2083                                      index);
2084                         result.SetStatus (eReturnStatusFailed);
2085                         return;
2086                     }
2087                     else
2088                     {
2089                         // Find and remove cmd_args.GetArgumentAtIndex(i) from raw_input_string
2090                         size_t strpos = raw_input_string.find (cmd_args.GetArgumentAtIndex (index));
2091                         if (strpos != std::string::npos)
2092                         {
2093                             raw_input_string = raw_input_string.erase (strpos, strlen (cmd_args.GetArgumentAtIndex (index)));
2094                         }
2095 
2096                         if (value_type != optional_argument)
2097                             new_args.AppendArgument (cmd_args.GetArgumentAtIndex (index));
2098                         else
2099                         {
2100                             char buffer[255];
2101                             ::snprintf (buffer, sizeof(buffer), "%s%s", option.c_str(),
2102                                         cmd_args.GetArgumentAtIndex (index));
2103                             new_args.AppendArgument (buffer);
2104                         }
2105                         used[index] = true;
2106                     }
2107                 }
2108             }
2109         }
2110 
2111         for (int j = 0; j < cmd_args.GetArgumentCount(); ++j)
2112         {
2113             if (!used[j] && !wants_raw_input)
2114                 new_args.AppendArgument (cmd_args.GetArgumentAtIndex (j));
2115         }
2116 
2117         cmd_args.Clear();
2118         cmd_args.SetArguments (new_args.GetArgumentCount(), (const char **) new_args.GetArgumentVector());
2119     }
2120     else
2121     {
2122         result.SetStatus (eReturnStatusSuccessFinishNoResult);
2123         // This alias was not created with any options; nothing further needs to be done, unless it is a command that
2124         // wants raw input, in which case we need to clear the rest of the data from cmd_args, since its in the raw
2125         // input string.
2126         if (wants_raw_input)
2127         {
2128             cmd_args.Clear();
2129             cmd_args.SetArguments (new_args.GetArgumentCount(), (const char **) new_args.GetArgumentVector());
2130         }
2131         return;
2132     }
2133 
2134     result.SetStatus (eReturnStatusSuccessFinishNoResult);
2135     return;
2136 }
2137 
2138 
2139 int
2140 CommandInterpreter::GetOptionArgumentPosition (const char *in_string)
2141 {
2142     int position = 0;   // Any string that isn't an argument position, i.e. '%' followed by an integer, gets a position
2143                         // of zero.
2144 
2145     char *cptr = (char *) in_string;
2146 
2147     // Does it start with '%'
2148     if (cptr[0] == '%')
2149     {
2150         ++cptr;
2151 
2152         // Is the rest of it entirely digits?
2153         if (isdigit (cptr[0]))
2154         {
2155             const char *start = cptr;
2156             while (isdigit (cptr[0]))
2157                 ++cptr;
2158 
2159             // We've gotten to the end of the digits; are we at the end of the string?
2160             if (cptr[0] == '\0')
2161                 position = atoi (start);
2162         }
2163     }
2164 
2165     return position;
2166 }
2167 
2168 void
2169 CommandInterpreter::SourceInitFile (bool in_cwd, CommandReturnObject &result)
2170 {
2171     FileSpec init_file;
2172     if (in_cwd)
2173     {
2174         // In the current working directory we don't load any program specific
2175         // .lldbinit files, we only look for a "./.lldbinit" file.
2176         if (m_skip_lldbinit_files)
2177             return;
2178 
2179         init_file.SetFile ("./.lldbinit", true);
2180     }
2181     else
2182     {
2183         // If we aren't looking in the current working directory we are looking
2184         // in the home directory. We will first see if there is an application
2185         // specific ".lldbinit" file whose name is "~/.lldbinit" followed by a
2186         // "-" and the name of the program. If this file doesn't exist, we fall
2187         // back to just the "~/.lldbinit" file. We also obey any requests to not
2188         // load the init files.
2189         const char *init_file_path = "~/.lldbinit";
2190 
2191         if (m_skip_app_init_files == false)
2192         {
2193             FileSpec program_file_spec (Host::GetProgramFileSpec());
2194             const char *program_name = program_file_spec.GetFilename().AsCString();
2195 
2196             if (program_name)
2197             {
2198                 char program_init_file_name[PATH_MAX];
2199                 ::snprintf (program_init_file_name, sizeof(program_init_file_name), "%s-%s", init_file_path, program_name);
2200                 init_file.SetFile (program_init_file_name, true);
2201                 if (!init_file.Exists())
2202                     init_file.Clear();
2203             }
2204         }
2205 
2206         if (!init_file && !m_skip_lldbinit_files)
2207 			init_file.SetFile (init_file_path, true);
2208     }
2209 
2210     // If the file exists, tell HandleCommand to 'source' it; this will do the actual broadcasting
2211     // of the commands back to any appropriate listener (see CommandObjectSource::Execute for more details).
2212 
2213     if (init_file.Exists())
2214     {
2215         ExecutionContext *exe_ctx = NULL;  // We don't have any context yet.
2216         bool stop_on_continue = true;
2217         bool stop_on_error    = false;
2218         bool echo_commands    = false;
2219         bool print_results    = false;
2220 
2221         HandleCommandsFromFile (init_file, exe_ctx, stop_on_continue, stop_on_error, echo_commands, print_results, eLazyBoolNo, result);
2222     }
2223     else
2224     {
2225         // nothing to be done if the file doesn't exist
2226         result.SetStatus(eReturnStatusSuccessFinishNoResult);
2227     }
2228 }
2229 
2230 PlatformSP
2231 CommandInterpreter::GetPlatform (bool prefer_target_platform)
2232 {
2233     PlatformSP platform_sp;
2234     if (prefer_target_platform)
2235     {
2236         ExecutionContext exe_ctx(GetExecutionContext());
2237         Target *target = exe_ctx.GetTargetPtr();
2238         if (target)
2239             platform_sp = target->GetPlatform();
2240     }
2241 
2242     if (!platform_sp)
2243         platform_sp = m_debugger.GetPlatformList().GetSelectedPlatform();
2244     return platform_sp;
2245 }
2246 
2247 void
2248 CommandInterpreter::HandleCommands (const StringList &commands,
2249                                     ExecutionContext *override_context,
2250                                     bool stop_on_continue,
2251                                     bool stop_on_error,
2252                                     bool echo_commands,
2253                                     bool print_results,
2254                                     LazyBool add_to_history,
2255                                     CommandReturnObject &result)
2256 {
2257     size_t num_lines = commands.GetSize();
2258 
2259     // If we are going to continue past a "continue" then we need to run the commands synchronously.
2260     // Make sure you reset this value anywhere you return from the function.
2261 
2262     bool old_async_execution = m_debugger.GetAsyncExecution();
2263 
2264     // If we've been given an execution context, set it at the start, but don't keep resetting it or we will
2265     // cause series of commands that change the context, then do an operation that relies on that context to fail.
2266 
2267     if (override_context != NULL)
2268         UpdateExecutionContext (override_context);
2269 
2270     if (!stop_on_continue)
2271     {
2272         m_debugger.SetAsyncExecution (false);
2273     }
2274 
2275     for (int idx = 0; idx < num_lines; idx++)
2276     {
2277         const char *cmd = commands.GetStringAtIndex(idx);
2278         if (cmd[0] == '\0')
2279             continue;
2280 
2281         if (echo_commands)
2282         {
2283             result.AppendMessageWithFormat ("%s %s\n",
2284                                              GetPrompt(),
2285                                              cmd);
2286         }
2287 
2288         CommandReturnObject tmp_result;
2289         // If override_context is not NULL, pass no_context_switching = true for
2290         // HandleCommand() since we updated our context already.
2291         bool success = HandleCommand(cmd, add_to_history, tmp_result,
2292                                      NULL, /* override_context */
2293                                      true, /* repeat_on_empty_command */
2294                                      override_context != NULL /* no_context_switching */);
2295 
2296         if (print_results)
2297         {
2298             if (tmp_result.Succeeded())
2299               result.AppendMessageWithFormat("%s", tmp_result.GetOutputData());
2300         }
2301 
2302         if (!success || !tmp_result.Succeeded())
2303         {
2304             const char *error_msg = tmp_result.GetErrorData();
2305             if (error_msg == NULL || error_msg[0] == '\0')
2306                 error_msg = "<unknown error>.\n";
2307             if (stop_on_error)
2308             {
2309                 result.AppendErrorWithFormat("Aborting reading of commands after command #%d: '%s' failed with %s",
2310                                          idx, cmd, error_msg);
2311                 result.SetStatus (eReturnStatusFailed);
2312                 m_debugger.SetAsyncExecution (old_async_execution);
2313                 return;
2314             }
2315             else if (print_results)
2316             {
2317                 result.AppendMessageWithFormat ("Command #%d '%s' failed with %s",
2318                                                 idx + 1,
2319                                                 cmd,
2320                                                 error_msg);
2321             }
2322         }
2323 
2324         if (result.GetImmediateOutputStream())
2325             result.GetImmediateOutputStream()->Flush();
2326 
2327         if (result.GetImmediateErrorStream())
2328             result.GetImmediateErrorStream()->Flush();
2329 
2330         // N.B. Can't depend on DidChangeProcessState, because the state coming into the command execution
2331         // could be running (for instance in Breakpoint Commands.
2332         // So we check the return value to see if it is has running in it.
2333         if ((tmp_result.GetStatus() == eReturnStatusSuccessContinuingNoResult)
2334                 || (tmp_result.GetStatus() == eReturnStatusSuccessContinuingResult))
2335         {
2336             if (stop_on_continue)
2337             {
2338                 // If we caused the target to proceed, and we're going to stop in that case, set the
2339                 // status in our real result before returning.  This is an error if the continue was not the
2340                 // last command in the set of commands to be run.
2341                 if (idx != num_lines - 1)
2342                     result.AppendErrorWithFormat("Aborting reading of commands after command #%d: '%s' continued the target.\n",
2343                                                  idx + 1, cmd);
2344                 else
2345                     result.AppendMessageWithFormat ("Command #%d '%s' continued the target.\n", idx + 1, cmd);
2346 
2347                 result.SetStatus(tmp_result.GetStatus());
2348                 m_debugger.SetAsyncExecution (old_async_execution);
2349 
2350                 return;
2351             }
2352         }
2353 
2354     }
2355 
2356     result.SetStatus (eReturnStatusSuccessFinishResult);
2357     m_debugger.SetAsyncExecution (old_async_execution);
2358 
2359     return;
2360 }
2361 
2362 void
2363 CommandInterpreter::HandleCommandsFromFile (FileSpec &cmd_file,
2364                                             ExecutionContext *context,
2365                                             bool stop_on_continue,
2366                                             bool stop_on_error,
2367                                             bool echo_command,
2368                                             bool print_result,
2369                                             LazyBool add_to_history,
2370                                             CommandReturnObject &result)
2371 {
2372     if (cmd_file.Exists())
2373     {
2374         bool success;
2375         StringList commands;
2376         success = commands.ReadFileLines(cmd_file);
2377         if (!success)
2378         {
2379             result.AppendErrorWithFormat ("Error reading commands from file: %s.\n", cmd_file.GetFilename().AsCString());
2380             result.SetStatus (eReturnStatusFailed);
2381             return;
2382         }
2383         m_command_source_depth++;
2384         HandleCommands (commands, context, stop_on_continue, stop_on_error, echo_command, print_result, add_to_history, result);
2385         m_command_source_depth--;
2386     }
2387     else
2388     {
2389         result.AppendErrorWithFormat ("Error reading commands from file %s - file not found.\n",
2390                                       cmd_file.GetFilename().AsCString());
2391         result.SetStatus (eReturnStatusFailed);
2392         return;
2393     }
2394 }
2395 
2396 ScriptInterpreter *
2397 CommandInterpreter::GetScriptInterpreter ()
2398 {
2399     // <rdar://problem/11751427>
2400     // we need to protect the initialization of the script interpreter
2401     // otherwise we could end up with two threads both trying to create
2402     // their instance of it, and for some languages (e.g. Python)
2403     // this is a bulletproof recipe for disaster!
2404     // this needs to be a function-level static because multiple Debugger instances living in the same process
2405     // still need to be isolated and not try to initialize Python concurrently
2406     static Mutex g_interpreter_mutex(Mutex::eMutexTypeRecursive);
2407     Mutex::Locker interpreter_lock(g_interpreter_mutex);
2408 
2409     if (m_script_interpreter_ap.get() != NULL)
2410         return m_script_interpreter_ap.get();
2411 
2412     lldb::ScriptLanguage script_lang = GetDebugger().GetScriptLanguage();
2413     switch (script_lang)
2414     {
2415         case eScriptLanguagePython:
2416 #ifndef LLDB_DISABLE_PYTHON
2417             m_script_interpreter_ap.reset (new ScriptInterpreterPython (*this));
2418             break;
2419 #else
2420             // Fall through to the None case when python is disabled
2421 #endif
2422         case eScriptLanguageNone:
2423             m_script_interpreter_ap.reset (new ScriptInterpreterNone (*this));
2424             break;
2425         default:
2426             break;
2427     };
2428 
2429     return m_script_interpreter_ap.get();
2430 }
2431 
2432 
2433 
2434 bool
2435 CommandInterpreter::GetSynchronous ()
2436 {
2437     return m_synchronous_execution;
2438 }
2439 
2440 void
2441 CommandInterpreter::SetSynchronous (bool value)
2442 {
2443     m_synchronous_execution  = value;
2444 }
2445 
2446 void
2447 CommandInterpreter::OutputFormattedHelpText (Stream &strm,
2448                                              const char *word_text,
2449                                              const char *separator,
2450                                              const char *help_text,
2451                                              uint32_t max_word_len)
2452 {
2453     const uint32_t max_columns = m_debugger.GetTerminalWidth();
2454 
2455     int indent_size = max_word_len + strlen (separator) + 2;
2456 
2457     strm.IndentMore (indent_size);
2458 
2459     StreamString text_strm;
2460     text_strm.Printf ("%-*s %s %s",  max_word_len, word_text, separator, help_text);
2461 
2462     size_t len = text_strm.GetSize();
2463     const char *text = text_strm.GetData();
2464     if (text[len - 1] == '\n')
2465     {
2466         text_strm.EOL();
2467         len = text_strm.GetSize();
2468     }
2469 
2470     if (len  < max_columns)
2471     {
2472         // Output it as a single line.
2473         strm.Printf ("%s", text);
2474     }
2475     else
2476     {
2477         // We need to break it up into multiple lines.
2478         bool first_line = true;
2479         int text_width;
2480         int start = 0;
2481         int end = start;
2482         int final_end = strlen (text);
2483         int sub_len;
2484 
2485         while (end < final_end)
2486         {
2487             if (first_line)
2488                 text_width = max_columns - 1;
2489             else
2490                 text_width = max_columns - indent_size - 1;
2491 
2492             // Don't start the 'text' on a space, since we're already outputting the indentation.
2493             if (!first_line)
2494             {
2495                 while ((start < final_end) && (text[start] == ' '))
2496                   start++;
2497             }
2498 
2499             end = start + text_width;
2500             if (end > final_end)
2501                 end = final_end;
2502             else
2503             {
2504                 // If we're not at the end of the text, make sure we break the line on white space.
2505                 while (end > start
2506                        && text[end] != ' ' && text[end] != '\t' && text[end] != '\n')
2507                     end--;
2508             }
2509 
2510             sub_len = end - start;
2511             if (start != 0)
2512               strm.EOL();
2513             if (!first_line)
2514                 strm.Indent();
2515             else
2516                 first_line = false;
2517             assert (start <= final_end);
2518             assert (start + sub_len <= final_end);
2519             if (sub_len > 0)
2520                 strm.Write (text + start, sub_len);
2521             start = end + 1;
2522         }
2523     }
2524     strm.EOL();
2525     strm.IndentLess(indent_size);
2526 }
2527 
2528 void
2529 CommandInterpreter::OutputHelpText (Stream &strm,
2530                                     const char *word_text,
2531                                     const char *separator,
2532                                     const char *help_text,
2533                                     uint32_t max_word_len)
2534 {
2535     int indent_size = max_word_len + strlen (separator) + 2;
2536 
2537     strm.IndentMore (indent_size);
2538 
2539     StreamString text_strm;
2540     text_strm.Printf ("%-*s %s %s",  max_word_len, word_text, separator, help_text);
2541 
2542     const uint32_t max_columns = m_debugger.GetTerminalWidth();
2543 
2544     size_t len = text_strm.GetSize();
2545     const char *text = text_strm.GetData();
2546 
2547     uint32_t chars_left = max_columns;
2548 
2549     for (uint32_t i = 0; i < len; i++)
2550     {
2551         if ((text[i] == ' ' && ::strchr((text+i+1), ' ') && chars_left < ::strchr((text+i+1), ' ')-(text+i)) || text[i] == '\n')
2552         {
2553             chars_left = max_columns - indent_size;
2554             strm.EOL();
2555             strm.Indent();
2556         }
2557         else
2558         {
2559             strm.PutChar(text[i]);
2560             chars_left--;
2561         }
2562 
2563     }
2564 
2565     strm.EOL();
2566     strm.IndentLess(indent_size);
2567 }
2568 
2569 void
2570 CommandInterpreter::AproposAllSubCommands (CommandObject *cmd_obj, const char *prefix, const char *search_word,
2571                                            StringList &commands_found, StringList &commands_help)
2572 {
2573     CommandObject::CommandMap::const_iterator pos;
2574     CommandObject::CommandMap sub_cmd_dict = ((CommandObjectMultiword *) cmd_obj)->m_subcommand_dict;
2575     CommandObject *sub_cmd_obj;
2576 
2577     for (pos = sub_cmd_dict.begin(); pos != sub_cmd_dict.end(); ++pos)
2578     {
2579           const char * command_name = pos->first.c_str();
2580           sub_cmd_obj = pos->second.get();
2581           StreamString complete_command_name;
2582 
2583           complete_command_name.Printf ("%s %s", prefix, command_name);
2584 
2585           if (sub_cmd_obj->HelpTextContainsWord (search_word))
2586           {
2587               commands_found.AppendString (complete_command_name.GetData());
2588               commands_help.AppendString (sub_cmd_obj->GetHelp());
2589           }
2590 
2591           if (sub_cmd_obj->IsMultiwordObject())
2592               AproposAllSubCommands (sub_cmd_obj, complete_command_name.GetData(), search_word, commands_found,
2593                                      commands_help);
2594     }
2595 
2596 }
2597 
2598 void
2599 CommandInterpreter::FindCommandsForApropos (const char *search_word, StringList &commands_found,
2600                                             StringList &commands_help)
2601 {
2602     CommandObject::CommandMap::const_iterator pos;
2603 
2604     for (pos = m_command_dict.begin(); pos != m_command_dict.end(); ++pos)
2605     {
2606         const char *command_name = pos->first.c_str();
2607         CommandObject *cmd_obj = pos->second.get();
2608 
2609         if (cmd_obj->HelpTextContainsWord (search_word))
2610         {
2611             commands_found.AppendString (command_name);
2612             commands_help.AppendString (cmd_obj->GetHelp());
2613         }
2614 
2615         if (cmd_obj->IsMultiwordObject())
2616           AproposAllSubCommands (cmd_obj, command_name, search_word, commands_found, commands_help);
2617 
2618     }
2619 }
2620 
2621 
2622 void
2623 CommandInterpreter::UpdateExecutionContext (ExecutionContext *override_context)
2624 {
2625     if (override_context != NULL)
2626     {
2627         m_exe_ctx_ref = *override_context;
2628     }
2629     else
2630     {
2631         const bool adopt_selected = true;
2632         m_exe_ctx_ref.SetTargetPtr (m_debugger.GetSelectedTarget().get(), adopt_selected);
2633     }
2634 }
2635 
2636 void
2637 CommandInterpreter::DumpHistory (Stream &stream, uint32_t count) const
2638 {
2639     DumpHistory (stream, 0, count - 1);
2640 }
2641 
2642 void
2643 CommandInterpreter::DumpHistory (Stream &stream, uint32_t start, uint32_t end) const
2644 {
2645     const size_t last_idx = std::min<size_t>(m_command_history.size(), end + 1);
2646     for (size_t i = start; i < last_idx; i++)
2647     {
2648         if (!m_command_history[i].empty())
2649         {
2650             stream.Indent();
2651             stream.Printf ("%4zu: %s\n", i, m_command_history[i].c_str());
2652         }
2653     }
2654 }
2655 
2656 const char *
2657 CommandInterpreter::FindHistoryString (const char *input_str) const
2658 {
2659     if (input_str[0] != m_repeat_char)
2660         return NULL;
2661     if (input_str[1] == '-')
2662     {
2663         bool success;
2664         uint32_t idx = Args::StringToUInt32 (input_str+2, 0, 0, &success);
2665         if (!success)
2666             return NULL;
2667         if (idx > m_command_history.size())
2668             return NULL;
2669         idx = m_command_history.size() - idx;
2670         return m_command_history[idx].c_str();
2671 
2672     }
2673     else if (input_str[1] == m_repeat_char)
2674     {
2675         if (m_command_history.empty())
2676             return NULL;
2677         else
2678             return m_command_history.back().c_str();
2679     }
2680     else
2681     {
2682         bool success;
2683         uint32_t idx = Args::StringToUInt32 (input_str+1, 0, 0, &success);
2684         if (!success)
2685             return NULL;
2686         if (idx >= m_command_history.size())
2687             return NULL;
2688         return m_command_history[idx].c_str();
2689     }
2690 }
2691