Implement simpleperf list subcommand.
simpleperf is used to replace linux/tools/perf. And This CL implements
the list subcommand of it.
Change-Id: I3e6fe854e19cc370070d0fd8416d0aa6fa8f8e90
diff --git a/simpleperf/cmd_help.cpp b/simpleperf/cmd_help.cpp
new file mode 100644
index 0000000..bf08dba
--- /dev/null
+++ b/simpleperf/cmd_help.cpp
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2015 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 <stdio.h>
+#include <string>
+#include <vector>
+
+#include <base/logging.h>
+
+#include "command.h"
+
+class HelpCommand : public Command {
+ public:
+ HelpCommand()
+ : Command("help", "print help information for simpleperf",
+ "Usage: simpleperf help [subcommand]\n"
+ " Without subcommand, print short help string for every subcommand.\n"
+ " With subcommand, print long help string for the subcommand.\n\n") {
+ }
+
+ bool Run(const std::vector<std::string>& args) override;
+
+ private:
+ void PrintShortHelp();
+ void PrintLongHelpForOneCommand(const Command& cmd);
+};
+
+bool HelpCommand::Run(const std::vector<std::string>& args) {
+ if (args.empty()) {
+ PrintShortHelp();
+ } else {
+ Command* cmd = Command::FindCommandByName(args[0]);
+ if (cmd == nullptr) {
+ LOG(ERROR) << "malformed command line: can't find help string for unknown command " << args[0];
+ LOG(ERROR) << "try using \"--help\"";
+ return false;
+ } else {
+ PrintLongHelpForOneCommand(*cmd);
+ }
+ }
+ return true;
+}
+
+void HelpCommand::PrintShortHelp() {
+ printf("Usage: simpleperf [--help] subcommand [args_for_subcommand]\n\n");
+ for (auto& command : Command::GetAllCommands()) {
+ printf("%-20s%s\n", command->Name().c_str(), command->ShortHelpString().c_str());
+ }
+}
+
+void HelpCommand::PrintLongHelpForOneCommand(const Command& command) {
+ printf("%s\n", command.LongHelpString().c_str());
+}
+
+HelpCommand help_command;