1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <stdio.h>
18 #include <string>
19 #include <vector>
20 
21 #include <android-base/logging.h>
22 
23 #include "command.h"
24 
25 class HelpCommand : public Command {
26  public:
27   HelpCommand()
28       : Command("help", "print help information for simpleperf",
29                 // clang-format off
30 "Usage: simpleperf help [subcommand]\n"
31 "    Without subcommand, print short help string for every subcommand.\n"
32 "    With subcommand, print long help string for the subcommand.\n\n"
33                 // clang-format on
34                 ) {}
35 
36   bool Run(const std::vector<std::string>& args) override;
37 
38  private:
39   void PrintShortHelp();
40   void PrintLongHelpForOneCommand(const Command& cmd);
41 };
42 
43 bool HelpCommand::Run(const std::vector<std::string>& args) {
44   if (args.empty()) {
45     PrintShortHelp();
46   } else {
47     std::unique_ptr<Command> cmd = CreateCommandInstance(args[0]);
48     if (cmd == nullptr) {
49       LOG(ERROR) << "malformed command line: can't find help string for "
50                     "unknown command "
51                  << args[0];
52       LOG(ERROR) << "try using \"--help\"";
53       return false;
54     } else {
55       PrintLongHelpForOneCommand(*cmd);
56     }
57   }
58   return true;
59 }
60 
61 void HelpCommand::PrintShortHelp() {
62   printf(
63       // clang-format off
64 "Usage: simpleperf [common options] subcommand [args_for_subcommand]\n"
65 "common options:\n"
66 "    -h/--help     Print this help information.\n"
67 "    --log <severity> Set the minimum severity of logging. Possible severities\n"
68 "                     include verbose, debug, warning, info, error, fatal.\n"
69 "                     Default is info.\n"
70 "    --version     Print version of simpleperf.\n"
71       "subcommands:\n"
72       // clang-format on
73       );
74   for (auto& cmd_name : GetAllCommandNames()) {
75     std::unique_ptr<Command> cmd = CreateCommandInstance(cmd_name);
76     printf("    %-20s%s\n", cmd_name.c_str(), cmd->ShortHelpString().c_str());
77   }
78 }
79 
80 void HelpCommand::PrintLongHelpForOneCommand(const Command& command) {
81   printf("%s\n", command.LongHelpString().c_str());
82 }
83 
84 void RegisterHelpCommand() {
85   RegisterCommand("help",
86                   [] { return std::unique_ptr<Command>(new HelpCommand); });
87 }
88