xref: /freebsd/contrib/kyua/cli/cmd_help.cpp (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
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28 
29 #include "cli/cmd_help.hpp"
30 
31 #include <algorithm>
32 #include <cstdlib>
33 
34 #include "cli/common.ipp"
35 #include "utils/cmdline/commands_map.ipp"
36 #include "utils/cmdline/exceptions.hpp"
37 #include "utils/cmdline/globals.hpp"
38 #include "utils/cmdline/options.hpp"
39 #include "utils/cmdline/parser.hpp"
40 #include "utils/cmdline/ui.hpp"
41 #include "utils/defs.hpp"
42 #include "utils/format/macros.hpp"
43 #include "utils/sanity.hpp"
44 #include "utils/text/table.hpp"
45 
46 namespace cmdline = utils::cmdline;
47 namespace config = utils::config;
48 namespace text = utils::text;
49 
50 using cli::cmd_help;
51 
52 
53 namespace {
54 
55 
56 /// Creates a table with the help of a set of options.
57 ///
58 /// \param options The set of options to describe.  May be empty.
59 ///
60 /// \return A 2-column wide table with the description of the options.
61 static text::table
62 options_help(const cmdline::options_vector& options)
63 {
64     text::table table(2);
65 
66     for (cmdline::options_vector::const_iterator iter = options.begin();
67          iter != options.end(); iter++) {
68         const cmdline::base_option* option = *iter;
69 
70         std::string description = option->description();
71         if (option->needs_arg() && option->has_default_value())
72             description += F(" (default: %s)") % option->default_value();
73 
74         text::table_row row;
75 
76         if (option->has_short_name())
77             row.push_back(F("%s, %s") % option->format_short_name() %
78                           option->format_long_name());
79         else
80             row.push_back(F("%s") % option->format_long_name());
81         row.push_back(F("%s.") % description);
82 
83         table.add_row(row);
84     }
85 
86     return table;
87 }
88 
89 
90 /// Prints the summary of commands and generic options.
91 ///
92 /// \param ui Object to interact with the I/O of the program.
93 /// \param options The set of program-wide options for which to print help.
94 /// \param commands The set of commands for which to print help.
95 static void
96 general_help(cmdline::ui* ui, const cmdline::options_vector* options,
97              const cmdline::commands_map< cli::cli_command >* commands)
98 {
99     PRE(!commands->empty());
100 
101     cli::write_version_header(ui);
102     ui->out("");
103     ui->out_tag_wrap(
104         "Usage: ",
105         F("%s [general_options] command [command_options] [args]") %
106         cmdline::progname(), false);
107 
108     const text::table options_table = options_help(*options);
109     text::widths_vector::value_type first_width =
110         options_table.column_width(0);
111 
112     std::map< std::string, text::table > command_tables;
113 
114     for (cmdline::commands_map< cli::cli_command >::const_iterator
115          iter = commands->begin(); iter != commands->end(); iter++) {
116         const std::string& category = (*iter).first;
117         const std::set< std::string >& command_names = (*iter).second;
118 
119         command_tables.insert(std::map< std::string, text::table >::value_type(
120             category, text::table(2)));
121         text::table& table = command_tables.find(category)->second;
122 
123         for (std::set< std::string >::const_iterator i2 = command_names.begin();
124              i2 != command_names.end(); i2++) {
125             const cli::cli_command* command = commands->find(*i2);
126             text::table_row row;
127             row.push_back(command->name());
128             row.push_back(F("%s.") % command->short_description());
129             table.add_row(row);
130         }
131 
132         if (table.column_width(0) > first_width)
133             first_width = table.column_width(0);
134     }
135 
136     text::table_formatter formatter;
137     formatter.set_column_width(0, first_width);
138     formatter.set_column_width(1, text::table_formatter::width_refill);
139     formatter.set_separator("  ");
140 
141     if (!options_table.empty()) {
142         ui->out_wrap("");
143         ui->out_wrap("Available general options:");
144         ui->out_table(options_table, formatter, "  ");
145     }
146 
147     // Iterate using the same loop as above to preserve ordering.
148     for (cmdline::commands_map< cli::cli_command >::const_iterator
149          iter = commands->begin(); iter != commands->end(); iter++) {
150         const std::string& category = (*iter).first;
151         ui->out_wrap("");
152         ui->out_wrap(F("%s commands:") %
153                 (category.empty() ? "Generic" : category));
154         ui->out_table(command_tables.find(category)->second, formatter, "  ");
155     }
156 
157     ui->out_wrap("");
158     ui->out_wrap("See kyua(1) for more details.");
159 }
160 
161 
162 /// Prints help for a particular subcommand.
163 ///
164 /// \param ui Object to interact with the I/O of the program.
165 /// \param general_options The options that apply to all commands.
166 /// \param command Pointer to the command to describe.
167 static void
168 subcommand_help(cmdline::ui* ui,
169                 const utils::cmdline::options_vector* general_options,
170                 const cli::cli_command* command)
171 {
172     cli::write_version_header(ui);
173     ui->out("");
174     ui->out_tag_wrap(
175         "Usage: ", F("%s [general_options] %s%s%s") %
176         cmdline::progname() % command->name() %
177         (command->options().empty() ? "" : " [command_options]") %
178         (command->arg_list().empty() ? "" : (" " + command->arg_list())),
179         false);
180     ui->out_wrap("");
181     ui->out_wrap(F("%s.") % command->short_description());
182 
183     const text::table general_table = options_help(*general_options);
184     const text::table command_table = options_help(command->options());
185 
186     const text::widths_vector::value_type first_width =
187         std::max(general_table.column_width(0), command_table.column_width(0));
188     text::table_formatter formatter;
189     formatter.set_column_width(0, first_width);
190     formatter.set_column_width(1, text::table_formatter::width_refill);
191     formatter.set_separator("  ");
192 
193     if (!general_table.empty()) {
194         ui->out_wrap("");
195         ui->out_wrap("Available general options:");
196         ui->out_table(general_table, formatter, "  ");
197     }
198 
199     if (!command_table.empty()) {
200         ui->out_wrap("");
201         ui->out_wrap("Available command options:");
202         ui->out_table(command_table, formatter, "  ");
203     }
204 
205     ui->out_wrap("");
206     ui->out_wrap(F("See kyua-%s(1) for more details.") % command->name());
207 }
208 
209 
210 }  // anonymous namespace
211 
212 
213 /// Default constructor for cmd_help.
214 ///
215 /// \param options_ The set of program-wide options for which to provide help.
216 /// \param commands_ The set of commands for which to provide help.
217 cmd_help::cmd_help(const cmdline::options_vector* options_,
218                    const cmdline::commands_map< cli_command >* commands_) :
219     cli_command("help", "[subcommand]", 0, 1, "Shows usage information"),
220     _options(options_),
221     _commands(commands_)
222 {
223 }
224 
225 
226 /// Entry point for the "help" subcommand.
227 ///
228 /// \param ui Object to interact with the I/O of the program.
229 /// \param cmdline Representation of the command line to the subcommand.
230 ///
231 /// \return 0 to indicate success.
232 int
233 cmd_help::run(utils::cmdline::ui* ui, const cmdline::parsed_cmdline& cmdline,
234               const config::tree& /* user_config */)
235 {
236     if (cmdline.arguments().empty()) {
237         general_help(ui, _options, _commands);
238     } else {
239         INV(cmdline.arguments().size() == 1);
240         const std::string& cmdname = cmdline.arguments()[0];
241         const cli::cli_command* command = _commands->find(cmdname);
242         if (command == NULL)
243             throw cmdline::usage_error(F("The command %s does not exist") %
244                                        cmdname);
245         else
246             subcommand_help(ui, _options, command);
247     }
248 
249     return EXIT_SUCCESS;
250 }
251