fix block cloning copy argument validation (#560)

1 files changed, 30 insertions, 0 deletions

diff --git a/src/zencore/filesystem.cpp b/src/zencore/filesystem.cpp
index f117001b5..85f7690bd 100644
--- a/src/zencore/filesystem.cpp
+++ b/src/zencore/filesystem.cpp
@@ -624,6 +624,9 @@ CopyTree(std::filesystem::path FromPath, std::filesystem::path ToPath, const Cop
 	if (ToPath.empty())
 		throw std::runtime_error("no CopyTree target specified");
 
+	if (Options.MustClone && !SupportsBlockRefCounting(FromPath))
+		throw std::runtime_error(fmt::format("cloning not possible from '{}'", FromPath));
+
 	if (std::filesystem::exists(ToPath))
 	{
 		if (!std::filesystem::is_directory(ToPath))
@@ -636,6 +639,33 @@ CopyTree(std::filesystem::path FromPath, std::filesystem::path ToPath, const Cop
 		std::filesystem::create_directories(ToPath);
 	}
 
+	if (Options.MustClone && !SupportsBlockRefCounting(ToPath))
+		throw std::runtime_error(fmt::format("cloning not possible from '{}'", ToPath));
+
+	// Verify source/target relationships
+
+	std::error_code		  Ec;
+	std::filesystem::path FromCanonical = std::filesystem::canonical(FromPath, Ec);
+
+	if (!Ec)
+	{
+		std::filesystem::path ToCanonical = std::filesystem::canonical(ToPath, Ec);
+
+		if (!Ec)
+		{
+			if (FromCanonical == ToCanonical)
+			{
+				throw std::runtime_error("Target and source must be distinct files or directories");
+			}
+
+			if (ToCanonical.generic_string().starts_with(FromCanonical.generic_string()) ||
+				FromCanonical.generic_string().starts_with(ToCanonical.generic_string()))
+			{
+				throw std::runtime_error("Invalid parent/child relationship for source/target directories");
+			}
+		}
+	}
+
 	struct CopyVisitor : public FileSystemTraversal::TreeVisitor
 	{
 		CopyVisitor(std::filesystem::path InBasePath, zen::CopyFileOptions InCopyOptions) : BasePath(InBasePath), CopyOptions(InCopyOptions)