GauthamBanasandra commented on code in PR #4370: URL: https://github.com/apache/hadoop/pull/4370#discussion_r890339355
########## hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/x-platform/c-api/dirent.cc: ########## @@ -0,0 +1,100 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 <algorithm> +#include <cerrno> +#include <iostream> +#include <iterator> +#include <system_error> +#include <variant> + +#include "x-platform/c-api/dirent.h" +#include "x-platform/dirent.h" + +#if defined(WIN32) && defined(__cplusplus) +extern "C" { +#endif + +DIR *opendir(const char *dir_path) { + const auto dir = new DIR; + dir->x_platform_dirent_ptr = new XPlatform::Dirent(dir_path); + return dir; +} + +struct dirent *readdir(DIR *dir) { + /* + * We will use a static variable to hold the dirent, so that we align with the + * readdir's implementation in dirent.h header file in Linux. + */ + static struct dirent static_dir_entry; + + // Get the XPlatform::Dirent instance and move the iterator. + const auto x_platform_dirent = + static_cast<XPlatform::Dirent *>(dir->x_platform_dirent_ptr); + const auto dir_entry = x_platform_dirent->NextFile(); + + // End of iteration. + if (std::holds_alternative<std::monostate>(dir_entry)) { + return nullptr; + } + + // Error in iteration. + if (std::holds_alternative<std::error_code>(dir_entry)) { + const auto err = std::get<std::error_code>(dir_entry); + errno = err.value(); + +#ifdef X_PLATFORM_C_API_DIRENT_DEBUG + std::cerr << "Error in listing directory: " << err.message() << std::endl; Review Comment: Yeah, I think it'll be useful for someone trying to debug any related issues. The same approach has been used already - https://github.com/apache/hadoop/blob/a234d00c1ce57427202d4c9587f891ec0164d10c/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs/jni_helper.c#L396-L398 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
