1 //===-- CommandObjectHelp.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 "CommandObjectHelp.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Interpreter/CommandObjectMultiword.h"
17 #include "lldb/Interpreter/CommandInterpreter.h"
18 #include "lldb/Interpreter/Options.h"
19 #include "lldb/Interpreter/CommandReturnObject.h"
20 
21 using namespace lldb;
22 using namespace lldb_private;
23 
24 //-------------------------------------------------------------------------
25 // CommandObjectHelp
26 //-------------------------------------------------------------------------
27 
28 CommandObjectHelp::CommandObjectHelp (CommandInterpreter &interpreter) :
29     CommandObjectParsed (interpreter,
30                          "help",
31                          "Show a list of all debugger commands, or give details about specific commands.",
32                          "help [<cmd-name>]"), m_options (interpreter)
33 {
34     CommandArgumentEntry arg;
35     CommandArgumentData command_arg;
36 
37     // Define the first (and only) variant of this arg.
38     command_arg.arg_type = eArgTypeCommandName;
39     command_arg.arg_repetition = eArgRepeatStar;
40 
41     // There is only one variant this argument could be; put it into the argument entry.
42     arg.push_back (command_arg);
43 
44     // Push the data for the first argument into the m_arguments vector.
45     m_arguments.push_back (arg);
46 }
47 
48 CommandObjectHelp::~CommandObjectHelp()
49 {
50 }
51 
52 OptionDefinition
53 CommandObjectHelp::CommandOptions::g_option_table[] =
54 {
55     { LLDB_OPT_SET_ALL, false, "show-aliases", 'a', no_argument, NULL, 0, eArgTypeNone,         "Show aliases in the command list."},
56     { LLDB_OPT_SET_ALL, false, "hide-user-commands", 'u', no_argument, NULL, 0, eArgTypeNone,         "Hide user-defined commands from the list."},
57     { 0, false, NULL, 0, 0, NULL, 0, eArgTypeNone, NULL }
58 };
59 
60 bool
61 CommandObjectHelp::DoExecute (Args& command, CommandReturnObject &result)
62 {
63     CommandObject::CommandMap::iterator pos;
64     CommandObject *cmd_obj;
65     const int argc = command.GetArgumentCount ();
66 
67     // 'help' doesn't take any arguments, other than command names.  If argc is 0, we show the user
68     // all commands (aliases and user commands if asked for).  Otherwise every argument must be the name of a command or a sub-command.
69     if (argc == 0)
70     {
71         uint32_t cmd_types = CommandInterpreter::eCommandTypesBuiltin;
72         if (m_options.m_show_aliases)
73             cmd_types |= CommandInterpreter::eCommandTypesAliases;
74         if (m_options.m_show_user_defined)
75             cmd_types |= CommandInterpreter::eCommandTypesUserDef;
76 
77         result.SetStatus (eReturnStatusSuccessFinishNoResult);
78         m_interpreter.GetHelp (result, cmd_types);  // General help
79     }
80     else
81     {
82         // Get command object for the first command argument. Only search built-in command dictionary.
83         StringList matches;
84         cmd_obj = m_interpreter.GetCommandObject (command.GetArgumentAtIndex (0), &matches);
85         bool is_alias_command = m_interpreter.AliasExists (command.GetArgumentAtIndex (0));
86         std::string alias_name = command.GetArgumentAtIndex(0);
87 
88         if (cmd_obj != NULL)
89         {
90             StringList matches;
91             bool all_okay = true;
92             CommandObject *sub_cmd_obj = cmd_obj;
93             // Loop down through sub_command dictionaries until we find the command object that corresponds
94             // to the help command entered.
95             for (int i = 1; i < argc && all_okay; ++i)
96             {
97                 std::string sub_command = command.GetArgumentAtIndex(i);
98                 matches.Clear();
99                 if (! sub_cmd_obj->IsMultiwordObject ())
100                 {
101                     all_okay = false;
102                 }
103                 else
104                 {
105                     CommandObject *found_cmd;
106                     found_cmd = sub_cmd_obj->GetSubcommandObject(sub_command.c_str(), &matches);
107                     if (found_cmd == NULL)
108                         all_okay = false;
109                     else if (matches.GetSize() > 1)
110                         all_okay = false;
111                     else
112                         sub_cmd_obj = found_cmd;
113                 }
114             }
115 
116             if (!all_okay || (sub_cmd_obj == NULL))
117             {
118                 std::string cmd_string;
119                 command.GetCommandString (cmd_string);
120                 if (matches.GetSize() < 2)
121                 {
122                     result.AppendErrorWithFormat("'%s' is not a known command.\n"
123                                                  "Try 'help' to see a current list of commands.\n",
124                                                  cmd_string.c_str());
125                 }
126                 else
127                 {
128                     StreamString s;
129                     s.Printf ("ambiguous command %s", cmd_string.c_str());
130                     size_t num_matches = matches.GetSize();
131                     for (size_t match_idx = 0; match_idx < num_matches; match_idx++)
132                     {
133                         s.Printf ("\n\t%s", matches.GetStringAtIndex(match_idx));
134                     }
135                     s.Printf ("\n");
136                     result.AppendError(s.GetData());
137                 }
138 
139                 result.SetStatus (eReturnStatusFailed);
140             }
141             else
142             {
143                 Stream &output_strm = result.GetOutputStream();
144                 if (sub_cmd_obj->GetOptions() != NULL)
145                 {
146                     if (sub_cmd_obj->WantsRawCommandString())
147                     {
148                         std::string help_text (sub_cmd_obj->GetHelp());
149                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
150                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
151                     }
152                     else
153                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
154                     output_strm.Printf ("\nSyntax: %s\n", sub_cmd_obj->GetSyntax());
155                     sub_cmd_obj->GetOptions()->GenerateOptionUsage (output_strm, sub_cmd_obj);
156                     const char *long_help = sub_cmd_obj->GetHelpLong();
157                     if ((long_help != NULL)
158                         && (strlen (long_help) > 0))
159                         output_strm.Printf ("\n%s", long_help);
160                     if (sub_cmd_obj->WantsRawCommandString() && !sub_cmd_obj->WantsCompletion())
161                     {
162                         // Emit the message about using ' -- ' between the end of the command options and the raw input
163                         // conditionally, i.e., only if the command object does not want completion.
164                         m_interpreter.OutputFormattedHelpText (output_strm, "", "",
165                                                                "\nIMPORTANT NOTE:  Because this command takes 'raw' input, if you use any command options"
166                                                                " you must use ' -- ' between the end of the command options and the beginning of the raw input.", 1);
167                     }
168                     else if (sub_cmd_obj->GetNumArgumentEntries() > 0
169                              && sub_cmd_obj->GetOptions()
170                              && sub_cmd_obj->GetOptions()->NumCommandOptions() > 0)
171                     {
172                             // Also emit a warning about using "--" in case you are using a command that takes options and arguments.
173                             m_interpreter.OutputFormattedHelpText (output_strm, "", "",
174                                                                    "\nThis command takes options and arguments, if your arguments look like option specifiers"
175                                                                    " you must use '--' to terminate the options before starting to give the arguments.", 1);
176                     }
177 
178                     // Mark this help command with a success status.
179                     result.SetStatus (eReturnStatusSuccessFinishNoResult);
180                 }
181                 else if (sub_cmd_obj->IsMultiwordObject())
182                 {
183                     if (sub_cmd_obj->WantsRawCommandString())
184                     {
185                         std::string help_text (sub_cmd_obj->GetHelp());
186                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
187                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
188                     }
189                     else
190                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
191                     sub_cmd_obj->GenerateHelpText (result);
192                 }
193                 else
194                 {
195                     const char *long_help = sub_cmd_obj->GetHelpLong();
196                     if ((long_help != NULL)
197                         && (strlen (long_help) > 0))
198                         output_strm.Printf ("%s", long_help);
199                     else if (sub_cmd_obj->WantsRawCommandString())
200                     {
201                         std::string help_text (sub_cmd_obj->GetHelp());
202                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
203                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
204                     }
205                     else
206                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
207                     output_strm.Printf ("\nSyntax: %s\n", sub_cmd_obj->GetSyntax());
208                     // Mark this help command with a success status.
209                     result.SetStatus (eReturnStatusSuccessFinishNoResult);
210                 }
211             }
212 
213             if (is_alias_command)
214             {
215                 StreamString sstr;
216                 m_interpreter.GetAliasHelp (alias_name.c_str(), cmd_obj->GetCommandName(), sstr);
217                 result.GetOutputStream().Printf ("\n'%s' is an abbreviation for %s\n", alias_name.c_str(), sstr.GetData());
218             }
219         }
220         else if (matches.GetSize() > 0)
221         {
222             Stream &output_strm = result.GetOutputStream();
223             output_strm.Printf("Help requested with ambiguous command name, possible completions:\n");
224             const uint32_t match_count = matches.GetSize();
225             for (uint32_t i = 0; i < match_count; i++)
226             {
227                 output_strm.Printf("\t%s\n", matches.GetStringAtIndex(i));
228             }
229         }
230         else
231         {
232             // Maybe the user is asking for help about a command argument rather than a command.
233             const CommandArgumentType arg_type = CommandObject::LookupArgumentName (command.GetArgumentAtIndex (0));
234             if (arg_type != eArgTypeLastArg)
235             {
236                 Stream &output_strm = result.GetOutputStream ();
237                 CommandObject::GetArgumentHelp (output_strm, arg_type, m_interpreter);
238                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
239             }
240             else
241             {
242                 result.AppendErrorWithFormat
243                     ("'%s' is not a known command.\nTry 'help' to see a current list of commands.\n",
244                      command.GetArgumentAtIndex(0));
245                 result.SetStatus (eReturnStatusFailed);
246             }
247         }
248     }
249 
250     return result.Succeeded();
251 }
252 
253 int
254 CommandObjectHelp::HandleCompletion
255 (
256     Args &input,
257     int &cursor_index,
258     int &cursor_char_position,
259     int match_start_point,
260     int max_return_elements,
261     bool &word_complete,
262     StringList &matches
263 )
264 {
265     // Return the completions of the commands in the help system:
266     if (cursor_index == 0)
267     {
268         return m_interpreter.HandleCompletionMatches (input,
269                                                     cursor_index,
270                                                     cursor_char_position,
271                                                     match_start_point,
272                                                     max_return_elements,
273                                                     word_complete,
274                                                     matches);
275     }
276     else
277     {
278         CommandObject *cmd_obj = m_interpreter.GetCommandObject (input.GetArgumentAtIndex(0));
279 
280         // The command that they are getting help on might be ambiguous, in which case we should complete that,
281         // otherwise complete with the command the user is getting help on...
282 
283         if (cmd_obj)
284         {
285             input.Shift();
286             cursor_index--;
287             return cmd_obj->HandleCompletion (input,
288                                               cursor_index,
289                                               cursor_char_position,
290                                               match_start_point,
291                                               max_return_elements,
292                                               word_complete,
293                                               matches);
294         }
295         else
296         {
297             return m_interpreter.HandleCompletionMatches (input,
298                                                         cursor_index,
299                                                         cursor_char_position,
300                                                         match_start_point,
301                                                         max_return_elements,
302                                                         word_complete,
303                                                         matches);
304         }
305     }
306 }
307