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, "hide-aliases", 'a', OptionParser::eNoArgument, NULL, NULL, 0, eArgTypeNone,         "Hide aliases in the command list."},
58     { LLDB_OPT_SET_ALL, false, "hide-user-commands", 'u', OptionParser::eNoArgument, NULL, NULL, 0, eArgTypeNone,         "Hide user-defined commands from the list."},
59     { LLDB_OPT_SET_ALL, false, "show-hidden-commands", 'h', OptionParser::eNoArgument, NULL, NULL, 0, eArgTypeNone,         "Include commands prefixed with an underscore."},
60     { 0, false, NULL, 0, 0, 0, NULL, 0, eArgTypeNone, NULL }
61 };
62 
63 bool
64 CommandObjectHelp::DoExecute (Args& command, CommandReturnObject &result)
65 {
66     CommandObject::CommandMap::iterator pos;
67     CommandObject *cmd_obj;
68     const size_t argc = command.GetArgumentCount ();
69 
70     // 'help' doesn't take any arguments, other than command names.  If argc is 0, we show the user
71     // all commands (aliases and user commands if asked for).  Otherwise every argument must be the name of a command or a sub-command.
72     if (argc == 0)
73     {
74         uint32_t cmd_types = CommandInterpreter::eCommandTypesBuiltin;
75         if (m_options.m_show_aliases)
76             cmd_types |= CommandInterpreter::eCommandTypesAliases;
77         if (m_options.m_show_user_defined)
78             cmd_types |= CommandInterpreter::eCommandTypesUserDef;
79         if (m_options.m_show_hidden)
80             cmd_types |= CommandInterpreter::eCommandTypesHidden;
81 
82         result.SetStatus (eReturnStatusSuccessFinishNoResult);
83         m_interpreter.GetHelp (result, cmd_types);  // General help
84     }
85     else
86     {
87         // Get command object for the first command argument. Only search built-in command dictionary.
88         StringList matches;
89         cmd_obj = m_interpreter.GetCommandObject (command.GetArgumentAtIndex (0), &matches);
90         bool is_alias_command = m_interpreter.AliasExists (command.GetArgumentAtIndex (0));
91         std::string alias_name = command.GetArgumentAtIndex(0);
92 
93         if (cmd_obj != NULL)
94         {
95             StringList matches;
96             bool all_okay = true;
97             CommandObject *sub_cmd_obj = cmd_obj;
98             // Loop down through sub_command dictionaries until we find the command object that corresponds
99             // to the help command entered.
100             for (size_t i = 1; i < argc && all_okay; ++i)
101             {
102                 std::string sub_command = command.GetArgumentAtIndex(i);
103                 matches.Clear();
104                 if (! sub_cmd_obj->IsMultiwordObject ())
105                 {
106                     all_okay = false;
107                 }
108                 else
109                 {
110                     CommandObject *found_cmd;
111                     found_cmd = sub_cmd_obj->GetSubcommandObject(sub_command.c_str(), &matches);
112                     if (found_cmd == NULL)
113                         all_okay = false;
114                     else if (matches.GetSize() > 1)
115                         all_okay = false;
116                     else
117                         sub_cmd_obj = found_cmd;
118                 }
119             }
120 
121             if (!all_okay || (sub_cmd_obj == NULL))
122             {
123                 std::string cmd_string;
124                 command.GetCommandString (cmd_string);
125                 if (matches.GetSize() >= 2)
126                 {
127                     StreamString s;
128                     s.Printf ("ambiguous command %s", cmd_string.c_str());
129                     size_t num_matches = matches.GetSize();
130                     for (size_t match_idx = 0; match_idx < num_matches; match_idx++)
131                     {
132                         s.Printf ("\n\t%s", matches.GetStringAtIndex(match_idx));
133                     }
134                     s.Printf ("\n");
135                     result.AppendError(s.GetData());
136                     result.SetStatus (eReturnStatusFailed);
137                     return false;
138                 }
139                 else if (!sub_cmd_obj)
140                 {
141                     result.AppendErrorWithFormat("'%s' is not a known command.\n"
142                                                  "Try '%shelp' to see a current list of commands.\n",
143                                                  cmd_string.c_str(),
144                                                  m_interpreter.GetCommandPrefix());
145                     result.SetStatus (eReturnStatusFailed);
146                     return false;
147                 }
148                 else
149                 {
150                     result.GetOutputStream().Printf("'%s' is not a known command.\n"
151                                                    "Try '%shelp' to see a current list of commands.\n"
152                                                     "The closest match is '%s'. Help on it follows.\n\n",
153                                                    cmd_string.c_str(),
154                                                    m_interpreter.GetCommandPrefix(),
155                                                    sub_cmd_obj->GetCommandName());
156                 }
157             }
158 
159             sub_cmd_obj->GenerateHelpText(result);
160 
161             if (is_alias_command)
162             {
163                 StreamString sstr;
164                 m_interpreter.GetAliasHelp (alias_name.c_str(), cmd_obj->GetCommandName(), sstr);
165                 result.GetOutputStream().Printf ("\n'%s' is an abbreviation for %s\n", alias_name.c_str(), sstr.GetData());
166             }
167         }
168         else if (matches.GetSize() > 0)
169         {
170             Stream &output_strm = result.GetOutputStream();
171             output_strm.Printf("Help requested with ambiguous command name, possible completions:\n");
172             const size_t match_count = matches.GetSize();
173             for (size_t i = 0; i < match_count; i++)
174             {
175                 output_strm.Printf("\t%s\n", matches.GetStringAtIndex(i));
176             }
177         }
178         else
179         {
180             // Maybe the user is asking for help about a command argument rather than a command.
181             const CommandArgumentType arg_type = CommandObject::LookupArgumentName (command.GetArgumentAtIndex (0));
182             if (arg_type != eArgTypeLastArg)
183             {
184                 Stream &output_strm = result.GetOutputStream ();
185                 CommandObject::GetArgumentHelp (output_strm, arg_type, m_interpreter);
186                 result.SetStatus (eReturnStatusSuccessFinishNoResult);
187             }
188             else
189             {
190                 result.AppendErrorWithFormat
191                     ("'%s' is not a known command.\nTry '%shelp' to see a current list of commands.\n",
192                      command.GetArgumentAtIndex(0),
193                      m_interpreter.GetCommandPrefix());
194                 result.SetStatus (eReturnStatusFailed);
195             }
196         }
197     }
198 
199     return result.Succeeded();
200 }
201 
202 int
203 CommandObjectHelp::HandleCompletion
204 (
205     Args &input,
206     int &cursor_index,
207     int &cursor_char_position,
208     int match_start_point,
209     int max_return_elements,
210     bool &word_complete,
211     StringList &matches
212 )
213 {
214     // Return the completions of the commands in the help system:
215     if (cursor_index == 0)
216     {
217         return m_interpreter.HandleCompletionMatches (input,
218                                                     cursor_index,
219                                                     cursor_char_position,
220                                                     match_start_point,
221                                                     max_return_elements,
222                                                     word_complete,
223                                                     matches);
224     }
225     else
226     {
227         CommandObject *cmd_obj = m_interpreter.GetCommandObject (input.GetArgumentAtIndex(0));
228 
229         // The command that they are getting help on might be ambiguous, in which case we should complete that,
230         // otherwise complete with the command the user is getting help on...
231 
232         if (cmd_obj)
233         {
234             input.Shift();
235             cursor_index--;
236             return cmd_obj->HandleCompletion (input,
237                                               cursor_index,
238                                               cursor_char_position,
239                                               match_start_point,
240                                               max_return_elements,
241                                               word_complete,
242                                               matches);
243         }
244         else
245         {
246             return m_interpreter.HandleCompletionMatches (input,
247                                                         cursor_index,
248                                                         cursor_char_position,
249                                                         match_start_point,
250                                                         max_return_elements,
251                                                         word_complete,
252                                                         matches);
253         }
254     }
255 }
256