platform_frameworks_native/cmds/lshal/HelpCommand.cpp
Yifan Hong 795b6ec895 lshal: Lshal register commands
Register commands to the controller class Lshal to autogenerate
help messages and select the correct Command.

Test: lshal_test
Change-Id: I846aef13d77bcee328c8410dc61f2e8b4c0e0d69
2017-09-14 13:40:27 -07:00

75 lines
2 KiB
C++

/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "HelpCommand.h"
#include "Lshal.h"
namespace android {
namespace lshal {
std::string HelpCommand::GetName() {
return "help";
}
std::string HelpCommand::getSimpleDescription() const {
return "Print help message.";
}
Status HelpCommand::main(const Arg &arg) {
if (optind >= arg.argc) {
// `lshal help` prints global usage.
mLshal.usage();
return OK;
}
(void)usageOfCommand(arg.argv[optind]);
return OK;
}
Status HelpCommand::usageOfCommand(const std::string& c) const {
if (c.empty()) {
mLshal.usage();
return USAGE;
}
auto command = mLshal.selectCommand(c);
if (command == nullptr) {
// from HelpCommand::main, `lshal help unknown`
mLshal.usage();
return USAGE;
}
command->usage();
return USAGE;
}
void HelpCommand::usage() const {
mLshal.err()
<< "help:" << std::endl
<< " lshal -h" << std::endl
<< " lshal --help" << std::endl
<< " lshal help" << std::endl
<< " Print this help message" << std::endl;
mLshal.forEachCommand([&](const Command* e) {
mLshal.err() << " lshal help " << e->getName() << std::endl
<< " Print help message for " << e->getName() << std::endl;
});
}
} // namespace lshal
} // namespace android