Merge pull request #5584 from dhthwy/filesystem_exceptions

use noexcept std::filesystem overloads

Author: ab9rf

docs/changelog.txt

@@ -57,6 +57,7 @@ Template for new versions:
 
 ## Fixes
 - `zone`: animal assignment dialog now tolerates corrupt animal-to-pasture links.
+- improved file system handling: gracefully handle errors from operations, preventing crashes.
 
 ## Misc Improvements
 

library/Core.cpp

@@ -535,7 +535,14 @@ std::filesystem::path Core::findScript(std::string name)
     getScriptPaths(&paths);
     for (auto it = paths.begin(); it != paths.end(); ++it)
     {
-        std::filesystem::path path = std::filesystem::weakly_canonical(*it / name);
+        std::error_code ec;
+        std::filesystem::path path = std::filesystem::weakly_canonical(*it / name, ec);
+        if (ec)
+        {
+            con.printerr("Error loading '%s' (%s)\n", (*it / name).string().c_str(), ec.message().c_str());
+            continue;
+        }
+
         if (Filesystem::isfile(path))
             return path;
     }

library/modules/Filesystem.cpp

@@ -154,17 +154,31 @@ bool Filesystem::stat (std::filesystem::path path, std::filesystem::file_status
 
 bool Filesystem::exists (std::filesystem::path path) noexcept
 {
-    return std::filesystem::exists(path);
+    std::error_code ec;
+    auto r = std::filesystem::exists(path, ec);
+    if (ec)
+        return false;
+    return r;
 }
 
 bool Filesystem::isfile(std::filesystem::path path) noexcept
 {
-    return std::filesystem::exists(path) && std::filesystem::is_regular_file(path);
+    std::error_code ec;
+    // is_regular_file() also checks for existence.
+    auto r = std::filesystem::is_regular_file(path, ec);
+    if (ec)
+        return false;
+    return r;
 }
 
 bool Filesystem::isdir (std::filesystem::path path) noexcept
 {
-    return std::filesystem::exists(path) && std::filesystem::is_directory(path);
+    std::error_code ec;
+    // is_directory() also checks for existence.
+    auto r = std::filesystem::is_directory(path, ec);
+    if (ec)
+        return false;
+    return r;
 }
 
 std::time_t Filesystem::mtime (std::filesystem::path path) noexcept