Rename asset_stream_manager to cdc_stream (#27)

Fixes #13

cdc_stream/base_command.cc

@@ -0,0 +1,110 @@
+// Copyright 2022 Google LLC
+//
+// 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 "cdc_stream/base_command.h"
+
+#include "absl/strings/str_format.h"
+#include "absl_helper/jedec_size_flag.h"
+#include "lyra/lyra.hpp"
+
+namespace cdc_ft {
+
+BaseCommand::BaseCommand(std::string name, std::string help, int* exit_code)
+    : name_(name), help_(help), exit_code_(exit_code) {
+  assert(exit_code_);
+}
+
+BaseCommand::~BaseCommand() = default;
+
+void BaseCommand::Register(lyra::cli& cli) {
+  lyra::command cmd(name_,
+                    [this](const lyra::group& g) { this->CommandHandler(g); });
+  cmd.help(help_);
+  cmd.add_argument(lyra::help(show_help_));
+
+  RegisterCommandLineFlags(cmd);
+
+  // Detect extra positional args.
+  cmd.add_argument(lyra::arg(PosArgValidator(&extra_positional_arg_), ""));
+
+  // Register command with CLI.
+  cli.add_argument(std::move(cmd));
+}
+
+std::function<void(const std::string&)> BaseCommand::JedecParser(
+    const char* flag_name, uint64_t* bytes) {
+  return [flag_name, bytes,
+          error = &jedec_parse_error_](const std::string& value) {
+    JedecSize size;
+    if (AbslParseFlag(value, &size, error)) {
+      *bytes = size.Size();
+    } else {
+      *error = absl::StrFormat("Failed to parse %s=%s: %s", flag_name, value,
+                               *error);
+    }
+  };
+}
+
+std::function<void(const std::string&)> BaseCommand::PosArgValidator(
+    std::string* str) {
+  return [str, invalid_arg = &invalid_arg_](const std::string& value) {
+    if (!value.empty() && value[0] == '-') {
+      *invalid_arg = value;
+    } else {
+      *str = value;
+    }
+  };
+}
+
+void BaseCommand::CommandHandler(const lyra::group& g) {
+  // Handle -h, --help.
+  if (show_help_) {
+    std::cout << g;
+    *exit_code_ = 0;
+    return;
+  }
+
+  // Handle invalid arguments.
+  if (!invalid_arg_.empty()) {
+    std::cerr << "Error: Unknown parameter '" << invalid_arg_
+              << "'. Try -h for help." << std::endl;
+    *exit_code_ = 1;
+    return;
+  }
+
+  if (!jedec_parse_error_.empty()) {
+    std::cerr << "Error: " << jedec_parse_error_ << std::endl;
+    *exit_code_ = 1;
+    return;
+  }
+
+  if (!extra_positional_arg_.empty()) {
+    std::cerr << "Error: Extraneous positional argument '"
+              << extra_positional_arg_ << "'. Try -h for help." << std::endl;
+    *exit_code_ = 1;
+    return;
+  }
+
+  // Run and print error.
+  absl::Status status = Run();
+  if (!status.ok()) {
+    std::cerr << "Error: " << status.message() << std::endl;
+  }
+
+  // Write status code to |exit_code_|.
+  static_assert(static_cast<int>(absl::StatusCode::kOk) == 0, "kOk not 0");
+  *exit_code_ = static_cast<int>(status.code());
+}
+
+}  // namespace cdc_ft