Add ghc_filesystem vendor library.

vendor/FileSystem/examples/CMakeLists.txt

@@ -0,0 +1,17 @@
+
+add_executable(fs_dir dir.cpp)
+target_link_libraries(fs_dir ghc_filesystem)
+if(CMAKE_CXX_COMPILER_ID MATCHES MSVC)
+    target_compile_definitions(fs_dir PRIVATE _CRT_SECURE_NO_WARNINGS)
+endif()
+AddExecutableWithStdFS(std_fs_dir dir.cpp)
+
+add_executable(fs_du du.cpp)
+target_link_libraries(fs_du ghc_filesystem)
+AddExecutableWithStdFS(std_fs_du du.cpp)
+
+if(EXISTS "${PROJECT_SOURCE_DIR}/examples/benchmark.cpp")
+    add_executable(fs_benchmark benchmark.cpp)
+    set_property(TARGET fs_benchmark PROPERTY CXX_STANDARD 17)
+    target_link_libraries(fs_benchmark ghc_filesystem)
+endif()

vendor/FileSystem/examples/dir.cpp

@@ -0,0 +1,60 @@
+#include <chrono>
+#include <iomanip>
+#include <iostream>
+#include <string>
+
+#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include)
+#if __has_include(<filesystem>)
+#define GHC_USE_STD_FS
+#include <filesystem>
+namespace fs = std::filesystem;
+#endif
+#endif
+#ifndef GHC_USE_STD_FS
+#include <ghc/filesystem.hpp>
+namespace fs = ghc::filesystem;
+#endif
+
+template <typename TP>
+std::time_t to_time_t(TP tp)
+{
+    // Based on trick from: Nico Josuttis, C++17 - The Complete Guide
+    std::chrono::system_clock::duration dt = std::chrono::duration_cast<std::chrono::system_clock::duration>(tp - TP::clock::now());
+    return std::chrono::system_clock::to_time_t(std::chrono::system_clock::now() + dt);
+}
+
+static std::string perm_to_str(fs::perms prms)
+{
+    std::string result;
+    result.reserve(9);
+    for (int i = 0; i < 9; ++i) {
+        result = ((static_cast<int>(prms) & (1 << i)) ? "xwrxwrxwr"[i] : '-') + result;
+    }
+    return result;
+}
+
+int main(int argc, char* argv[])
+{
+#ifdef GHC_FILESYSTEM_VERSION
+    fs::u8arguments u8guard(argc, argv);
+    if (!u8guard.valid()) {
+        std::cerr << "Invalid character encoding, UTF-8 based encoding needed." << std::endl;
+        std::exit(EXIT_FAILURE);
+    }
+#endif
+    if (argc > 2) {
+        std::cerr << "USAGE: dir <path>" << std::endl;
+        exit(1);
+    }
+    fs::path dir{"."};
+    if (argc == 2) {
+        dir = fs::u8path(argv[1]);
+    }
+    for (auto de : fs::directory_iterator(dir)) {
+        auto ft = to_time_t(de.last_write_time());
+        auto ftm = *std::localtime(&ft);
+        std::cout << (de.is_directory() ? "d" : "-") << perm_to_str(de.symlink_status().permissions()) << "  " << std::setw(8) << (de.is_directory() ? "-" : std::to_string(de.file_size())) << "  " << std::put_time(&ftm, "%Y-%m-%d %H:%M:%S") << "  "
+                  << de.path().filename().string() << std::endl;
+    }
+    return 0;
+}

vendor/FileSystem/examples/du.cpp

@@ -0,0 +1,61 @@
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+
+#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include)
+#if __has_include(<filesystem>)
+#define GHC_USE_STD_FS
+#include <filesystem>
+namespace fs = std::filesystem;
+#endif
+#endif
+#ifndef GHC_USE_STD_FS
+#include <ghc/filesystem.hpp>
+namespace fs = ghc::filesystem;
+#endif
+
+int main(int argc, char* argv[])
+{
+#ifdef GHC_FILESYSTEM_VERSION
+    fs::u8arguments u8guard(argc, argv);
+    if(!u8guard.valid()) {
+        std::cerr << "Invalid character encoding, UTF-8 based encoding needed." << std::endl;
+        std::exit(EXIT_FAILURE);
+    }
+#endif
+    if(argc > 2) {
+        std::cerr << "USAGE: du <path>" << std::endl;
+        exit(1);
+    }
+    fs::path dir{"."};
+    if(argc == 2) {
+        dir = fs::u8path(argv[1]);
+    }
+
+    uint64_t totalSize = 0;
+    int totalDirs = 0;
+    int totalFiles = 0;
+    int maxDepth = 0;
+    
+    try {
+        auto rdi = fs::recursive_directory_iterator(dir);
+        for(auto de : rdi) {
+            if(rdi.depth() > maxDepth) {
+                maxDepth = rdi.depth();
+            }
+            if(de.is_regular_file()) {
+                totalSize += de.file_size();
+                ++totalFiles;
+            }
+            else if(de.is_directory()) {
+                ++totalDirs;
+            }
+        }
+    }
+    catch(fs::filesystem_error fe) {
+        std::cerr << "Error: " << fe.what() << std::endl;
+        exit(1);
+    }
+    std::cout << totalSize << " bytes in " << totalFiles << " files and " << totalDirs << " directories, maximum depth: " << maxDepth << std::endl;
+    return 0;
+}