szaszm commented on a change in pull request #1138: URL: https://github.com/apache/nifi-minifi-cpp/pull/1138#discussion_r696504277
########## File path: libminifi/include/utils/file/FilePattern.h ########## @@ -0,0 +1,122 @@ +/** + * 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. + */ + +#pragma once + +#include <string> +#include <vector> +#include <set> +#include <utility> +#include <memory> +#include <filesystem> + +#include "utils/OptionalUtils.h" +#include "core/logging/Logger.h" + +struct FilePatternTestAccessor; + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace utils { +namespace file { + +class FilePatternError : public std::invalid_argument { +public: + explicit FilePatternError(const std::string& msg) : invalid_argument(msg) {} +}; + +class FilePattern { + friend struct ::FilePatternTestAccessor; + + friend std::set<std::filesystem::path> match(const FilePattern& pattern); + + class FilePatternSegmentError : public std::invalid_argument { + public: + explicit FilePatternSegmentError(const std::string& msg) : invalid_argument(msg) {} + }; + + class FilePatternSegment { + static void defaultSegmentErrorHandler(std::string_view error_message) { + throw FilePatternError(std::string{error_message}); Review comment: We can save an allocation by passing `const char*` (`error_message.c_str()`). Exceptions need to make a copy of the string internally regardless if it's std::string or anything else, due to special requirements. ########## File path: libminifi/include/core/extension/DynamicLibrary.h ########## @@ -0,0 +1,69 @@ +/** + * 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. + */ + +#pragma once + +#include <memory> +#include <map> +#include <string> +#include <filesystem> + +#include "Module.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +class DynamicLibrary : public Module { + friend class ExtensionManager; + + public: + DynamicLibrary(std::string name, std::filesystem::path library_path); + ~DynamicLibrary() override; + + private: +#ifdef WIN32 + std::map<void*, std::string> resource_mapping_; + + std::string error_str_; + std::string current_error_; + + void store_error(); + void* dlsym(void* handle, const char* name); + const char* dlerror(); + void* dlopen(const char* file, int mode); + int dlclose(void* handle); +#endif + + bool load(); + bool unload(); + + std::filesystem::path library_path_; + gsl::owner<void*> handle_ = nullptr; + + static std::shared_ptr<logging::Logger> logger_; Review comment: If we never need to change the logger instance, then this could be `const`. ########## File path: libminifi/src/core/extension/ExtensionManager.cpp ########## @@ -0,0 +1,134 @@ +/** + * 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 "core/extension/ExtensionManager.h" +#include "core/logging/LoggerConfiguration.h" +#include "utils/file/FileUtils.h" +#include "core/extension/Executable.h" +#include "utils/file/FilePattern.h" +#include "core/extension/DynamicLibrary.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +namespace { +struct LibraryDescriptor { + std::string name; + std::filesystem::path dir; + std::string filename; + + bool verify(const std::shared_ptr<logging::Logger>& /*logger*/) const { + // TODO(adebreceni): check signature + return true; + } + + std::filesystem::path getFullPath() const { + return dir / filename; + } +}; +} // namespace + +static std::optional<LibraryDescriptor> asDynamicLibrary(const std::filesystem::path& path) { +#if defined(WIN32) + const std::string extension = ".dll"; +#elif defined(__APPLE__) + const std::string extension = ".dylib"; +#else + const std::string extension = ".so"; +#endif + +#ifdef WIN32 + const std::string prefix = ""; +#else + const std::string prefix = "lib"; +#endif Review comment: Did you consider `std::string_view` or `const char*`? It's fine as is, but relying on SSO gives me a somewhat uneasy feeling. ########## File path: libminifi/include/utils/file/FilePattern.h ########## @@ -0,0 +1,122 @@ +/** + * 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. + */ + +#pragma once + +#include <string> +#include <vector> +#include <set> +#include <utility> +#include <memory> +#include <filesystem> + +#include "utils/OptionalUtils.h" +#include "core/logging/Logger.h" + +struct FilePatternTestAccessor; + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace utils { +namespace file { + +class FilePatternError : public std::invalid_argument { + public: + explicit FilePatternError(const std::string& msg) : invalid_argument(msg) {} +}; + +class FilePattern { + friend struct ::FilePatternTestAccessor; + + friend std::set<std::filesystem::path> match(const FilePattern& pattern); + + class FilePatternSegmentError : public std::invalid_argument { + public: + explicit FilePatternSegmentError(const std::string& msg) : invalid_argument(msg) {} + }; + + class FilePatternSegment { + static void defaultSegmentErrorHandler(std::string_view error_message) { + throw FilePatternError(std::string{error_message}); + } + + public: + explicit FilePatternSegment(std::string pattern); + + enum class MatchResult { + INCLUDE, // dir/file should be processed according to the pattern + EXCLUDE, // dir/file is explicitly rejected by the pattern + NOT_MATCHING // dir/file does not match pattern, do what you may + }; + + bool isExcluding() const { + return excluding_; + } + + MatchResult match(const std::string& directory) const; + + MatchResult match(const std::string& directory, const std::string& filename) const; + + MatchResult match(const std::filesystem::path& path) const; + /** + * @return The lowermost parent directory without wildcards. + */ + std::filesystem::path getBaseDirectory() const; + + private: + enum class DirMatchResult { + NONE, // pattern does not match the directory (e.g. p = "/home/inner/*test", v = "/home/banana") + PARENT, // directory is a parent of the pattern (e.g. p = "/home/inner/*test", v = "/home/inner") + EXACT, // pattern exactly matches the directory (e.g. p = "/home/inner/*test", v = "/home/inner/cool_test") + TREE // pattern matches the whole subtree of the directory (e.g. p = "/home/**", v = "/home/banana") + }; + + using DirIt = std::filesystem::path::const_iterator; + static DirMatchResult matchDirectory(DirIt pattern_begin, DirIt pattern_end, DirIt value_begin, DirIt value_end); + + std::filesystem::path directory_pattern_; + std::string file_pattern_; + bool excluding_; + }; + + using ErrorHandler = std::function<void(std::string_view /*subpattern*/, std::string_view /*error_message*/)>; + + static void defaultErrorHandler(std::string_view subpattern, std::string_view error_message) { + std::string message = "Error in subpattern '"; + message += subpattern; + message += "': "; + message += error_message; + throw FilePatternError(message); + } + + public: + explicit FilePattern(const std::string& pattern, ErrorHandler error_handler = defaultErrorHandler); + + private: + std::vector<FilePatternSegment> segments_; +}; + +std::set<std::filesystem::path> match(const FilePattern& pattern); Review comment: Can we make this return a vector? Unless we need set specifically for some reason. ########## File path: libminifi/src/core/extension/ExtensionManager.cpp ########## @@ -0,0 +1,134 @@ +/** + * 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 "core/extension/ExtensionManager.h" +#include "core/logging/LoggerConfiguration.h" +#include "utils/file/FileUtils.h" +#include "core/extension/Executable.h" +#include "utils/file/FilePattern.h" +#include "core/extension/DynamicLibrary.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +namespace { +struct LibraryDescriptor { + std::string name; + std::filesystem::path dir; + std::string filename; + + bool verify(const std::shared_ptr<logging::Logger>& /*logger*/) const { + // TODO(adebreceni): check signature + return true; + } + + std::filesystem::path getFullPath() const { + return dir / filename; + } +}; +} // namespace + +static std::optional<LibraryDescriptor> asDynamicLibrary(const std::filesystem::path& path) { Review comment: Moving this inside the anonymous namespace would have the same effect as `static`. I would move it, since there is one already. ########## File path: libminifi/src/core/extension/DynamicLibrary.cpp ########## @@ -0,0 +1,201 @@ +/** + * 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 <memory> +#ifndef WIN32 +#include <dlfcn.h> +#define DLL_EXPORT +#else +#define WIN32_LEAN_AND_MEAN 1 +#include <Windows.h> // Windows specific libraries for collecting software metrics. +#include <Psapi.h> +#pragma comment(lib, "psapi.lib" ) +#define DLL_EXPORT __declspec(dllexport) +#define RTLD_LAZY 0 +#define RTLD_NOW 0 + +#define RTLD_GLOBAL (1 << 1) +#define RTLD_LOCAL (1 << 2) +#endif + +#include "core/extension/DynamicLibrary.h" +#include "core/extension/Extension.h" +#include "utils/GeneralUtils.h" +#include "core/logging/LoggerConfiguration.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +std::shared_ptr<logging::Logger> DynamicLibrary::logger_ = logging::LoggerFactory<DynamicLibrary>::getLogger(); + +DynamicLibrary::DynamicLibrary(std::string name, std::filesystem::path library_path) + : Module(std::move(name)), + library_path_(std::move(library_path)) { +} + +bool DynamicLibrary::load() { + dlerror(); + handle_ = dlopen(library_path_.string().c_str(), RTLD_NOW | RTLD_LOCAL); + if (!handle_) { + logger_->log_error("Failed to load extension '%s' at '%s': %s", name_, library_path_.string(), dlerror()); + return false; + } else { + logger_->log_trace("Loaded extension '%s' at '%s'", name_, library_path_.string()); + return true; + } +} + +bool DynamicLibrary::unload() { + logger_->log_trace("Unloading library '%s' at '%s'", name_, library_path_.string()); + if (!handle_) { + logger_->log_error("Extension does not have a handle_ '%s' at '%s'", name_, library_path_.string()); + return true; + } + dlerror(); + if (dlclose(handle_)) { + logger_->log_error("Failed to unload extension '%s' at '%': %s", name_, library_path_.string(), dlerror()); + return false; + } + logger_->log_trace("Unloaded extension '%s' at '%s'", name_, library_path_.string()); + handle_ = nullptr; + return true; +} + +DynamicLibrary::~DynamicLibrary() = default; + +#ifdef WIN32 + +void DynamicLibrary::store_error() { + auto error = GetLastError(); + + if (error == 0) { + error_str_ = ""; + return; + } + + LPSTR messageBuffer = nullptr; + size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, + NULL, error, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&messageBuffer, 0, NULL); + + current_error_ = std::string(messageBuffer, size); + + // Free the buffer. + LocalFree(messageBuffer); +} + +void* DynamicLibrary::dlsym(void* handle, const char* name) { + FARPROC symbol; + + symbol = GetProcAddress((HMODULE)handle, name); + + if (symbol == nullptr) { + store_error(); + + for (auto hndl : resource_mapping_) { + symbol = GetProcAddress((HMODULE)hndl.first, name); + if (symbol != nullptr) { + break; + } + } + } + +#ifdef _MSC_VER +#pragma warning(suppress: 4054 ) +#endif + return reinterpret_cast<void*>(symbol); +} + +const char* DynamicLibrary::dlerror() { + error_str_ = current_error_; + + current_error_ = ""; + + return error_str_.c_str(); +} + +void* DynamicLibrary::dlopen(const char* file, int mode) { + HMODULE object; + uint32_t uMode = SetErrorMode(SEM_FAILCRITICALERRORS); + if (nullptr == file) { + HMODULE allModules[1024]; + HANDLE current_process_id = GetCurrentProcess(); Review comment: This is not really an id, but a handle. I would rename to current_process. ########## File path: libminifi/include/core/extension/DynamicLibrary.h ########## @@ -0,0 +1,69 @@ +/** + * 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. + */ + +#pragma once + +#include <memory> +#include <map> +#include <string> +#include <filesystem> + +#include "Module.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +class DynamicLibrary : public Module { + friend class ExtensionManager; + + public: + DynamicLibrary(std::string name, std::filesystem::path library_path); + ~DynamicLibrary() override; + + private: +#ifdef WIN32 + std::map<void*, std::string> resource_mapping_; + + std::string error_str_; + std::string current_error_; + + void store_error(); + void* dlsym(void* handle, const char* name); + const char* dlerror(); + void* dlopen(const char* file, int mode); + int dlclose(void* handle); Review comment: Instead of strictly replicating the POSIX API, I would consider changing the signature to return a unique_ptr and maybe signal error with exceptions or similar. This could save us some state space by not needing to store errors on windows. I'm fine with leaving it as is, this is just an idea. ########## File path: libminifi/src/core/extension/ExtensionManager.cpp ########## @@ -0,0 +1,134 @@ +/** + * 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 "core/extension/ExtensionManager.h" +#include "core/logging/LoggerConfiguration.h" +#include "utils/file/FileUtils.h" +#include "core/extension/Executable.h" +#include "utils/file/FilePattern.h" +#include "core/extension/DynamicLibrary.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +namespace { +struct LibraryDescriptor { + std::string name; + std::filesystem::path dir; + std::string filename; + + bool verify(const std::shared_ptr<logging::Logger>& /*logger*/) const { + // TODO(adebreceni): check signature + return true; + } + + std::filesystem::path getFullPath() const { + return dir / filename; + } +}; +} // namespace + +static std::optional<LibraryDescriptor> asDynamicLibrary(const std::filesystem::path& path) { +#if defined(WIN32) + const std::string extension = ".dll"; +#elif defined(__APPLE__) + const std::string extension = ".dylib"; +#else + const std::string extension = ".so"; +#endif + +#ifdef WIN32 + const std::string prefix = ""; +#else + const std::string prefix = "lib"; +#endif + std::string filename = path.filename().string(); + if (!utils::StringUtils::startsWith(filename, prefix) || !utils::StringUtils::endsWith(filename, extension)) { + return {}; + } + return LibraryDescriptor{ + filename.substr(prefix.length(), filename.length() - extension.length() - prefix.length()), + path.parent_path(), + filename + }; +} + +std::shared_ptr<logging::Logger> ExtensionManager::logger_ = logging::LoggerFactory<ExtensionManager>::getLogger(); + +ExtensionManager::ExtensionManager() { + modules_.push_back(std::make_unique<Executable>()); + active_module_ = modules_[0].get(); +} + +ExtensionManager& ExtensionManager::get() { + static ExtensionManager instance; + return instance; +} + +bool ExtensionManager::initialize(const std::shared_ptr<Configure>& config) { + static bool initialized = ([&] { + logger_->log_trace("Initializing extensions"); + // initialize executable + active_module_->initialize(config); + std::optional<std::string> pattern = config ? config->get(nifi_extension_path) : std::nullopt; + if (!pattern) return; + auto candidates = utils::file::match(utils::file::FilePattern(pattern.value(), [&] (std::string_view subpattern, std::string_view error_msg) { + logger_->log_error("Error in subpattern '%s': %s", std::string{subpattern}, std::string{error_msg}); Review comment: It might be worth to make a `std::string_view` overload of conditional_conversion in Logger.h. ########## File path: libminifi/include/core/logging/Logger.h ########## @@ -70,6 +75,8 @@ inline T conditional_conversion(T t) { return t; } + + Review comment: Not sure if we need this many empty lines. :) ########## File path: libminifi/src/core/extension/DynamicLibrary.cpp ########## @@ -0,0 +1,201 @@ +/** + * 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 <memory> +#ifndef WIN32 +#include <dlfcn.h> +#define DLL_EXPORT +#else +#define WIN32_LEAN_AND_MEAN 1 +#include <Windows.h> // Windows specific libraries for collecting software metrics. +#include <Psapi.h> +#pragma comment(lib, "psapi.lib" ) +#define DLL_EXPORT __declspec(dllexport) +#define RTLD_LAZY 0 +#define RTLD_NOW 0 + +#define RTLD_GLOBAL (1 << 1) +#define RTLD_LOCAL (1 << 2) +#endif + +#include "core/extension/DynamicLibrary.h" +#include "core/extension/Extension.h" +#include "utils/GeneralUtils.h" +#include "core/logging/LoggerConfiguration.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { +namespace extension { + +std::shared_ptr<logging::Logger> DynamicLibrary::logger_ = logging::LoggerFactory<DynamicLibrary>::getLogger(); + +DynamicLibrary::DynamicLibrary(std::string name, std::filesystem::path library_path) + : Module(std::move(name)), + library_path_(std::move(library_path)) { +} + +bool DynamicLibrary::load() { + dlerror(); + handle_ = dlopen(library_path_.c_str(), RTLD_NOW | RTLD_LOCAL); + if (!handle_) { + logger_->log_error("Failed to load extension '%s' at '%s': %s", name_, library_path_, dlerror()); + return false; + } else { + logger_->log_trace("Loaded extension '%s' at '%s'", name_, library_path_); + return true; + } +} + +bool DynamicLibrary::unload() { + logger_->log_trace("Unloading library '%s' at '%s'", name_, library_path_); + if (!handle_) { + logger_->log_error("Extension does not have a handle_ '%s' at '%s'", name_, library_path_); + return true; + } + dlerror(); + if (dlclose(handle_)) { + logger_->log_error("Failed to unload extension '%s' at '%': %s", name_, library_path_, dlerror()); + return false; + } + logger_->log_trace("Unloaded extension '%s' at '%s'", name_, library_path_); + handle_ = nullptr; + return true; +} + +DynamicLibrary::~DynamicLibrary() = default; + +#ifdef WIN32 + +void DynamicLibrary::store_error() { + auto error = GetLastError(); + + if (error == 0) { + error_str_ = ""; + return; + } + + LPSTR messageBuffer = nullptr; + size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, + NULL, error, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&messageBuffer, 0, NULL); + + current_error_ = std::string(messageBuffer, size); + + // Free the buffer. + LocalFree(messageBuffer); +} Review comment: Check out `get_last_socket_error_message` in ClientSocket.cpp. It's an easier way to get error messages, using system_error. -- This is an automated message from the Apache Git Service. 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