1 //===-- CommandObjectHelp.cpp ---------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "CommandObjectHelp.h"
10 #include "lldb/Interpreter/CommandInterpreter.h"
11 #include "lldb/Interpreter/CommandOptionArgumentTable.h"
12 #include "lldb/Interpreter/CommandReturnObject.h"
13
14 using namespace lldb;
15 using namespace lldb_private;
16
17 // CommandObjectHelp
18
GenerateAdditionalHelpAvenuesMessage(Stream * s,llvm::StringRef command,llvm::StringRef prefix,llvm::StringRef subcommand,bool include_upropos,bool include_type_lookup)19 void CommandObjectHelp::GenerateAdditionalHelpAvenuesMessage(
20 Stream *s, llvm::StringRef command, llvm::StringRef prefix,
21 llvm::StringRef subcommand, bool include_upropos,
22 bool include_type_lookup) {
23 if (!s || command.empty())
24 return;
25
26 std::string command_str = command.str();
27 std::string prefix_str = prefix.str();
28 std::string subcommand_str = subcommand.str();
29 const std::string &lookup_str =
30 !subcommand_str.empty() ? subcommand_str : command_str;
31 s->Printf("'%s' is not a known command.\n", command_str.c_str());
32 s->Printf("Try '%shelp' to see a current list of commands.\n",
33 prefix.str().c_str());
34 if (include_upropos) {
35 s->Printf("Try '%sapropos %s' for a list of related commands.\n",
36 prefix_str.c_str(), lookup_str.c_str());
37 }
38 if (include_type_lookup) {
39 s->Printf("Try '%stype lookup %s' for information on types, methods, "
40 "functions, modules, etc.",
41 prefix_str.c_str(), lookup_str.c_str());
42 }
43 }
44
CommandObjectHelp(CommandInterpreter & interpreter)45 CommandObjectHelp::CommandObjectHelp(CommandInterpreter &interpreter)
46 : CommandObjectParsed(interpreter, "help",
47 "Show a list of all debugger "
48 "commands, or give details "
49 "about a specific command.",
50 "help [<cmd-name>]") {
51 // A list of command names forming a path to the command we want help on.
52 // No names is allowed - in which case we dump the top-level help.
53 AddSimpleArgumentList(eArgTypeCommand, eArgRepeatStar);
54 }
55
56 CommandObjectHelp::~CommandObjectHelp() = default;
57
58 #define LLDB_OPTIONS_help
59 #include "CommandOptions.inc"
60
61 llvm::ArrayRef<OptionDefinition>
GetDefinitions()62 CommandObjectHelp::CommandOptions::GetDefinitions() {
63 return llvm::ArrayRef(g_help_options);
64 }
65
DoExecute(Args & command,CommandReturnObject & result)66 void CommandObjectHelp::DoExecute(Args &command, CommandReturnObject &result) {
67 CommandObject::CommandMap::iterator pos;
68 CommandObject *cmd_obj;
69 const size_t argc = command.GetArgumentCount();
70
71 // 'help' doesn't take any arguments, other than command names. If argc is
72 // 0, we show the user all commands (aliases and user commands if asked for).
73 // Otherwise every argument must be the name of a command or a sub-command.
74 if (argc == 0) {
75 uint32_t cmd_types = CommandInterpreter::eCommandTypesBuiltin;
76 if (m_options.m_show_aliases)
77 cmd_types |= CommandInterpreter::eCommandTypesAliases;
78 if (m_options.m_show_user_defined) {
79 cmd_types |= CommandInterpreter::eCommandTypesUserDef;
80 cmd_types |= CommandInterpreter::eCommandTypesUserMW;
81 }
82 if (m_options.m_show_hidden)
83 cmd_types |= CommandInterpreter::eCommandTypesHidden;
84
85 result.SetStatus(eReturnStatusSuccessFinishNoResult);
86 m_interpreter.GetHelp(result, cmd_types); // General help
87 } else {
88 // Get command object for the first command argument. Only search built-in
89 // command dictionary.
90 StringList matches;
91 auto command_name = command[0].ref();
92 cmd_obj = m_interpreter.GetCommandObject(command_name, &matches);
93
94 if (cmd_obj != nullptr) {
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
99 // object that corresponds to the help command entered.
100 std::string sub_command;
101 for (auto &entry : command.entries().drop_front()) {
102 sub_command = std::string(entry.ref());
103 matches.Clear();
104 if (sub_cmd_obj->IsAlias())
105 sub_cmd_obj =
106 ((CommandAlias *)sub_cmd_obj)->GetUnderlyingCommand().get();
107 if (!sub_cmd_obj->IsMultiwordObject()) {
108 all_okay = false;
109 break;
110 } else {
111 CommandObject *found_cmd;
112 found_cmd =
113 sub_cmd_obj->GetSubcommandObject(sub_command.c_str(), &matches);
114 if (found_cmd == nullptr || matches.GetSize() > 1) {
115 all_okay = false;
116 break;
117 } else
118 sub_cmd_obj = found_cmd;
119 }
120 }
121
122 if (!all_okay || (sub_cmd_obj == nullptr)) {
123 std::string cmd_string;
124 command.GetCommandString(cmd_string);
125 if (matches.GetSize() >= 2) {
126 StreamString s;
127 s.Printf("ambiguous command %s", cmd_string.c_str());
128 size_t num_matches = matches.GetSize();
129 for (size_t match_idx = 0; match_idx < num_matches; match_idx++) {
130 s.Printf("\n\t%s", matches.GetStringAtIndex(match_idx));
131 }
132 s.Printf("\n");
133 result.AppendError(s.GetString());
134 return;
135 } else if (!sub_cmd_obj) {
136 StreamString error_msg_stream;
137 GenerateAdditionalHelpAvenuesMessage(
138 &error_msg_stream, cmd_string.c_str(),
139 m_interpreter.GetCommandPrefix(), sub_command.c_str());
140 result.AppendError(error_msg_stream.GetString());
141 return;
142 } else {
143 GenerateAdditionalHelpAvenuesMessage(
144 &result.GetOutputStream(), cmd_string.c_str(),
145 m_interpreter.GetCommandPrefix(), sub_command.c_str());
146 result.GetOutputStream().Printf(
147 "\nThe closest match is '%s'. Help on it follows.\n\n",
148 sub_cmd_obj->GetCommandName().str().c_str());
149 }
150 }
151
152 sub_cmd_obj->GenerateHelpText(result);
153 std::string alias_full_name;
154 // Don't use AliasExists here, that only checks exact name matches. If
155 // the user typed a shorter unique alias name, we should still tell them
156 // it was an alias.
157 if (m_interpreter.GetAliasFullName(command_name, alias_full_name)) {
158 StreamString sstr;
159 m_interpreter.GetAlias(alias_full_name)->GetAliasExpansion(sstr);
160 result.GetOutputStream().Printf("\n'%s' is an abbreviation for %s\n",
161 command[0].c_str(), sstr.GetData());
162 }
163 } else if (matches.GetSize() > 0) {
164 Stream &output_strm = result.GetOutputStream();
165 output_strm.Printf("Help requested with ambiguous command name, possible "
166 "completions:\n");
167 const size_t match_count = matches.GetSize();
168 for (size_t i = 0; i < match_count; i++) {
169 output_strm.Printf("\t%s\n", matches.GetStringAtIndex(i));
170 }
171 } else {
172 // Maybe the user is asking for help about a command argument rather than
173 // a command.
174 const CommandArgumentType arg_type =
175 CommandObject::LookupArgumentName(command_name);
176 if (arg_type != eArgTypeLastArg) {
177 Stream &output_strm = result.GetOutputStream();
178 CommandObject::GetArgumentHelp(output_strm, arg_type, m_interpreter);
179 result.SetStatus(eReturnStatusSuccessFinishNoResult);
180 } else {
181 StreamString error_msg_stream;
182 GenerateAdditionalHelpAvenuesMessage(&error_msg_stream, command_name,
183 m_interpreter.GetCommandPrefix(),
184 "");
185 result.AppendError(error_msg_stream.GetString());
186 }
187 }
188 }
189 }
190
HandleCompletion(CompletionRequest & request)191 void CommandObjectHelp::HandleCompletion(CompletionRequest &request) {
192 // Return the completions of the commands in the help system:
193 if (request.GetCursorIndex() == 0) {
194 m_interpreter.HandleCompletionMatches(request);
195 return;
196 }
197 CommandObject *cmd_obj =
198 m_interpreter.GetCommandObject(request.GetParsedLine()[0].ref());
199
200 // The command that they are getting help on might be ambiguous, in which
201 // case we should complete that, otherwise complete with the command the
202 // user is getting help on...
203
204 if (cmd_obj) {
205 request.ShiftArguments();
206 cmd_obj->HandleCompletion(request);
207 return;
208 }
209 m_interpreter.HandleCompletionMatches(request);
210 }
211