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 "lldb/lldb-python.h"
11 
12 #include "CommandObjectHelp.h"
13 
14 // C Includes
15 // C++ Includes
16 // Other libraries and framework includes
17 // Project includes
18 #include "lldb/Interpreter/CommandObjectMultiword.h"
19 #include "lldb/Interpreter/CommandInterpreter.h"
20 #include "lldb/Interpreter/Options.h"
21 #include "lldb/Interpreter/CommandReturnObject.h"
22 
23 using namespace lldb;
24 using namespace lldb_private;
25 
26 //-------------------------------------------------------------------------
27 // CommandObjectHelp
28 //-------------------------------------------------------------------------
29 
30 CommandObjectHelp::CommandObjectHelp (CommandInterpreter &interpreter) :
31     CommandObjectParsed (interpreter,
32                          "help",
33                          "Show a list of all debugger commands, or give details about specific commands.",
34                          "help [<cmd-name>]"), m_options (interpreter)
35 {
36     CommandArgumentEntry arg;
37     CommandArgumentData command_arg;
38 
39     // Define the first (and only) variant of this arg.
40     command_arg.arg_type = eArgTypeCommandName;
41     command_arg.arg_repetition = eArgRepeatStar;
42 
43     // There is only one variant this argument could be; put it into the argument entry.
44     arg.push_back (command_arg);
45 
46     // Push the data for the first argument into the m_arguments vector.
47     m_arguments.push_back (arg);
48 }
49 
50 CommandObjectHelp::~CommandObjectHelp()
51 {
52 }
53 
54 OptionDefinition
55 CommandObjectHelp::CommandOptions::g_option_table[] =
56 {
57     { LLDB_OPT_SET_ALL, false, "show-aliases", 'a', no_argument, NULL, 0, eArgTypeNone,         "Show aliases in the command list."},
58     { LLDB_OPT_SET_ALL, false, "hide-user-commands", 'u', no_argument, NULL, 0, eArgTypeNone,         "Hide user-defined commands from the list."},
59     { 0, false, NULL, 0, 0, NULL, 0, eArgTypeNone, NULL }
60 };
61 
62 bool
63 CommandObjectHelp::DoExecute (Args& command, CommandReturnObject &result)
64 {
65     CommandObject::CommandMap::iterator pos;
66     CommandObject *cmd_obj;
67     const size_t argc = command.GetArgumentCount ();
68 
69     // 'help' doesn't take any arguments, other than command names.  If argc is 0, we show the user
70     // all commands (aliases and user commands if asked for).  Otherwise every argument must be the name of a command or a sub-command.
71     if (argc == 0)
72     {
73         uint32_t cmd_types = CommandInterpreter::eCommandTypesBuiltin;
74         if (m_options.m_show_aliases)
75             cmd_types |= CommandInterpreter::eCommandTypesAliases;
76         if (m_options.m_show_user_defined)
77             cmd_types |= CommandInterpreter::eCommandTypesUserDef;
78 
79         result.SetStatus (eReturnStatusSuccessFinishNoResult);
80         m_interpreter.GetHelp (result, cmd_types);  // General help
81     }
82     else
83     {
84         // Get command object for the first command argument. Only search built-in command dictionary.
85         StringList matches;
86         cmd_obj = m_interpreter.GetCommandObject (command.GetArgumentAtIndex (0), &matches);
87         bool is_alias_command = m_interpreter.AliasExists (command.GetArgumentAtIndex (0));
88         std::string alias_name = command.GetArgumentAtIndex(0);
89 
90         if (cmd_obj != NULL)
91         {
92             StringList matches;
93             bool all_okay = true;
94             CommandObject *sub_cmd_obj = cmd_obj;
95             // Loop down through sub_command dictionaries until we find the command object that corresponds
96             // to the help command entered.
97             for (int i = 1; i < argc && all_okay; ++i)
98             {
99                 std::string sub_command = command.GetArgumentAtIndex(i);
100                 matches.Clear();
101                 if (! sub_cmd_obj->IsMultiwordObject ())
102                 {
103                     all_okay = false;
104                 }
105                 else
106                 {
107                     CommandObject *found_cmd;
108                     found_cmd = sub_cmd_obj->GetSubcommandObject(sub_command.c_str(), &matches);
109                     if (found_cmd == NULL)
110                         all_okay = false;
111                     else if (matches.GetSize() > 1)
112                         all_okay = false;
113                     else
114                         sub_cmd_obj = found_cmd;
115                 }
116             }
117 
118             if (!all_okay || (sub_cmd_obj == NULL))
119             {
120                 std::string cmd_string;
121                 command.GetCommandString (cmd_string);
122                 if (matches.GetSize() < 2)
123                 {
124                     result.AppendErrorWithFormat("'%s' is not a known command.\n"
125                                                  "Try 'help' to see a current list of commands.\n",
126                                                  cmd_string.c_str());
127                 }
128                 else
129                 {
130                     StreamString s;
131                     s.Printf ("ambiguous command %s", cmd_string.c_str());
132                     size_t num_matches = matches.GetSize();
133                     for (size_t match_idx = 0; match_idx < num_matches; match_idx++)
134                     {
135                         s.Printf ("\n\t%s", matches.GetStringAtIndex(match_idx));
136                     }
137                     s.Printf ("\n");
138                     result.AppendError(s.GetData());
139                 }
140 
141                 result.SetStatus (eReturnStatusFailed);
142             }
143             else
144             {
145                 Stream &output_strm = result.GetOutputStream();
146                 if (sub_cmd_obj->GetOptions() != NULL)
147                 {
148                     if (sub_cmd_obj->WantsRawCommandString())
149                     {
150                         std::string help_text (sub_cmd_obj->GetHelp());
151                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
152                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
153                     }
154                     else
155                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
156                     output_strm.Printf ("\nSyntax: %s\n", sub_cmd_obj->GetSyntax());
157                     sub_cmd_obj->GetOptions()->GenerateOptionUsage (output_strm, sub_cmd_obj);
158                     const char *long_help = sub_cmd_obj->GetHelpLong();
159                     if ((long_help != NULL)
160                         && (strlen (long_help) > 0))
161                         output_strm.Printf ("\n%s", long_help);
162                     if (sub_cmd_obj->WantsRawCommandString() && !sub_cmd_obj->WantsCompletion())
163                     {
164                         // Emit the message about using ' -- ' between the end of the command options and the raw input
165                         // conditionally, i.e., only if the command object does not want completion.
166                         m_interpreter.OutputFormattedHelpText (output_strm, "", "",
167                                                                "\nIMPORTANT NOTE:  Because this command takes 'raw' input, if you use any command options"
168                                                                " you must use ' -- ' between the end of the command options and the beginning of the raw input.", 1);
169                     }
170                     else if (sub_cmd_obj->GetNumArgumentEntries() > 0
171                              && sub_cmd_obj->GetOptions()
172                              && sub_cmd_obj->GetOptions()->NumCommandOptions() > 0)
173                     {
174                             // Also emit a warning about using "--" in case you are using a command that takes options and arguments.
175                             m_interpreter.OutputFormattedHelpText (output_strm, "", "",
176                                                                    "\nThis command takes options and free-form arguments.  If your arguments resemble"
177                                                                    " option specifiers (i.e., they start with a - or --), you must use ' -- ' between"
178                                                                    " the end of the command options and the beginning of the arguments.", 1);
179                     }
180 
181                     // Mark this help command with a success status.
182                     result.SetStatus (eReturnStatusSuccessFinishNoResult);
183                 }
184                 else if (sub_cmd_obj->IsMultiwordObject())
185                 {
186                     if (sub_cmd_obj->WantsRawCommandString())
187                     {
188                         std::string help_text (sub_cmd_obj->GetHelp());
189                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
190                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
191                     }
192                     else
193                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
194                     sub_cmd_obj->GenerateHelpText (result);
195                 }
196                 else
197                 {
198                     const char *long_help = sub_cmd_obj->GetHelpLong();
199                     if ((long_help != NULL)
200                         && (strlen (long_help) > 0))
201                         output_strm.Printf ("%s", long_help);
202                     else if (sub_cmd_obj->WantsRawCommandString())
203                     {
204                         std::string help_text (sub_cmd_obj->GetHelp());
205                         help_text.append ("  This command takes 'raw' input (no need to quote stuff).");
206                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", help_text.c_str(), 1);
207                     }
208                     else
209                         m_interpreter.OutputFormattedHelpText (output_strm, "", "", sub_cmd_obj->GetHelp(), 1);
210                     output_strm.Printf ("\nSyntax: %s\n", sub_cmd_obj->GetSyntax());
211                     // Mark this help command with a success status.
212                     result.SetStatus (eReturnStatusSuccessFinishNoResult);
213                 }
214             }
215 
216             if (is_alias_command)
217             {
218                 StreamString sstr;
219                 m_interpreter.GetAliasHelp (alias_name.c_str(), cmd_obj->GetCommandName(), sstr);
220                 result.GetOutputStream().Printf ("\n'%s' is an abbreviation for %s\n", alias_name.c_str(), sstr.GetData());
221             }
222         }
223         else if (matches.GetSize() > 0)
224         {
225             Stream &output_strm = result.GetOutputStream();
226             output_strm.Printf("Help requested with ambiguous command name, possible completions:\n");
227             const size_t match_count = matches.GetSize();
228             for (size_t i = 0; i < match_count; i++)
229             {
230                 output_strm.Printf("\t%s\n", matches.GetStringAtIndex(i));
231             }
232         }
233         else
234         {
235             // Maybe the user is asking for help about a command argument rather than a command.
236             const CommandArgumentType arg_type = CommandObject::LookupArgumentName (command.GetArgumentAtIndex (0));
237             if (arg_type != eArgTypeLastArg)
238             {
239                 Stream &output_strm = result.GetOutputStream ();
240                 CommandObject::GetArgumentHelp (output_strm, arg_type, m_interpreter);
241                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
242             }
243             else
244             {
245                 result.AppendErrorWithFormat
246                     ("'%s' is not a known command.\nTry 'help' to see a current list of commands.\n",
247                      command.GetArgumentAtIndex(0));
248                 result.SetStatus (eReturnStatusFailed);
249             }
250         }
251     }
252 
253     return result.Succeeded();
254 }
255 
256 int
257 CommandObjectHelp::HandleCompletion
258 (
259     Args &input,
260     int &cursor_index,
261     int &cursor_char_position,
262     int match_start_point,
263     int max_return_elements,
264     bool &word_complete,
265     StringList &matches
266 )
267 {
268     // Return the completions of the commands in the help system:
269     if (cursor_index == 0)
270     {
271         return m_interpreter.HandleCompletionMatches (input,
272                                                     cursor_index,
273                                                     cursor_char_position,
274                                                     match_start_point,
275                                                     max_return_elements,
276                                                     word_complete,
277                                                     matches);
278     }
279     else
280     {
281         CommandObject *cmd_obj = m_interpreter.GetCommandObject (input.GetArgumentAtIndex(0));
282 
283         // The command that they are getting help on might be ambiguous, in which case we should complete that,
284         // otherwise complete with the command the user is getting help on...
285 
286         if (cmd_obj)
287         {
288             input.Shift();
289             cursor_index--;
290             return cmd_obj->HandleCompletion (input,
291                                               cursor_index,
292                                               cursor_char_position,
293                                               match_start_point,
294                                               max_return_elements,
295                                               word_complete,
296                                               matches);
297         }
298         else
299         {
300             return m_interpreter.HandleCompletionMatches (input,
301                                                         cursor_index,
302                                                         cursor_char_position,
303                                                         match_start_point,
304                                                         max_return_elements,
305                                                         word_complete,
306                                                         matches);
307         }
308     }
309 }
310