From ec210a87dbc4a04a102e20015ae8d0f0f973237c Mon Sep 17 00:00:00 2001
From: Dion Moult <dion@thinkmoult.com>
Date: Mon, 14 Sep 2026 13:04:50 +1000
Subject: [PATCH] ifcparse: use std::filesystem in guess_file_type()

The stat()-based path helpers were added in 573e53ebf as a speculative
workaround for #7131 ("Ugly workarounds to not depend on
std::filesystem"). That issue turned out to be a hardcoded schema list
missing HEADER_SECTION_SCHEMA and was fixed separately.

Since the plug-in architecture landed, libIfcParse already depends on
std::filesystem: schema.h exports schema_plugin_directory() returning a
std::filesystem::path, and plugin.cpp uses it throughout. The build also
mandates C++17. The workaround therefore no longer avoids anything and
its comment is misleading.

Restore the std::filesystem version, using the error_code overloads so
inaccessible paths are still reported as "not there" rather than
throwing, and route the path through ifcopenshell::path::from_utf8 so
non-ASCII paths work on Windows, as file_reader.cpp already does.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WcUNL8YygRrNC5KpxELMHs
---
 src/ifcparse/file.cpp | 59 ++++++++++---------------------------------
 1 file changed, 13 insertions(+), 46 deletions(-)

diff --git a/src/ifcparse/file.cpp b/src/ifcparse/file.cpp
index dc6a313880..8c805e52c2 100644
--- a/src/ifcparse/file.cpp
+++ b/src/ifcparse/file.cpp
@@ -1,5 +1,6 @@
 #include "file.h"
 #include "logger.h"
+#include "utils.h"
 
 #ifdef IFOPSH_WITH_ROCKSDB
 #include <rocksdb/table.h>
@@ -7,10 +8,10 @@
 #include <rocksdb/version.h>
 #endif
 
+#include <filesystem>
 #include <fstream>
 #include <memory>
-#include <sys/types.h>
-#include <sys/stat.h>
+#include <system_error>
 #include <utility>
 
 /*
@@ -269,58 +270,24 @@ express::base ifcopenshell::impl::in_memory_file_storage::instance_by_id(int id)
 
 ifcopenshell::file::~file() {}
 
-namespace {
-	// Utility functions for path handling in order not to rely on C++17's std::filesystem
-#ifdef _WIN32
-#define stat_t struct _stat
-    inline int stat_(const char* p, stat_t* s) { return ::_stat(p, s); }
-#ifndef S_ISDIR
-#define S_ISDIR(m) (((m) & _S_IFDIR) != 0)
-#endif
-#ifndef S_ISREG
-#define S_ISREG(m) (((m) & _S_IFREG) != 0)
-#endif
-#else
-    using stat_t = struct stat;
-    inline int stat_(const char* p, stat_t* s) { return ::stat(p, s); }
-#endif
-
-    inline bool path_exists_(const std::string& p, stat_t* out = nullptr) {
-        stat_t tmp;
-        stat_t* s = out ? out : &tmp;
-        return stat_(p.c_str(), s) == 0;
-    }
-
-    inline bool path_is_directory_(const stat_t& s) { return S_ISDIR(s.st_mode); }
-    inline bool path_is_regular_file_(const stat_t& s) { return S_ISREG(s.st_mode); }
-
-    inline std::string path_join_(const std::string& dir, const std::string& name) {
-        if (dir.empty()) return name;
-        const char last = dir.back();
-        if (last == '/' || last == '\\') return dir + name;
-#ifdef _WIN32
-        const char sep = '\\';
-#else
-        const char sep = '/';
-#endif
-        return dir + sep + name;
-    }
-} // namespace
-
 ifcopenshell::filetype ifcopenshell::guess_file_type(const std::string& fn) {
-    stat_t st{};
-    if (!path_exists_(fn, &st)) {
+    namespace fs = std::filesystem;
+
+    // The error_code overloads report inaccessible paths as "not there"
+    // instead of throwing, matching the previous stat()-based behaviour.
+    std::error_code ec;
+    const fs::path path(ifcopenshell::path::from_utf8(fn));
+    if (!fs::exists(path, ec)) {
         // @todo this is just weird, but for consistency with earlier behaviour
         // for now the only intent for this function is to auto-detect RocksDB
         return FT_IFCSPF;
     }
 
-    if (path_is_directory_(st)) {
+    if (fs::is_directory(path, ec)) {
         // Typical RocksDB file to look for
-        auto currentFile = path_join_(fn, "CURRENT");
-        stat_t cst{};
+        const auto currentFile = path / "CURRENT";
 
-        if (!path_exists_(currentFile, &cst) || !path_is_regular_file_(cst)) {
+        if (!fs::is_regular_file(currentFile, ec)) {
             return FT_UNKNOWN;
         }