optimizations (#200)

* Use direct file read and direct buffer allocation for small IoBuffer materalization
* Reduce range of materialized data in CompositeBuffer reading
CompressedBuffer header reading often only need a small part and not the whole file
* reduce lock contention in IoBuffer::Materialize
* Reduce parsing of compressed headers
Validate header type at decompression
* faster CreateDirectories - start from leaf going up and recurse back
* optimized BufferHeader::IsValid
* Add ValidateCompressedHeader to use when we don't need the actual compressed data
Validate that we always get compressed data in CidStore::AddChunk
* changelog

1 files changed, 13 insertions, 5 deletions

diff --git a/zencore/filesystem.cpp b/zencore/filesystem.cpp
index 0aa478404..1e4a52638 100644
--- a/zencore/filesystem.cpp
+++ b/zencore/filesystem.cpp
@@ -188,13 +188,21 @@ CleanDirectory(const wchar_t* DirPath)
 bool
 CreateDirectories(const std::filesystem::path& Dir)
 {
-	std::error_code ErrorCode;
-	bool			WasCreated = std::filesystem::create_directories(Dir, ErrorCode);
-	if (ErrorCode)
+	while (!std::filesystem::is_directory(Dir))
 	{
-		throw std::system_error(ErrorCode, fmt::format("Failed to create directories for '{}'", Dir.string()));
+		if (Dir.has_parent_path())
+		{
+			CreateDirectories(Dir.parent_path());
+		}
+		std::error_code ErrorCode;
+		std::filesystem::create_directory(Dir, ErrorCode);
+		if (ErrorCode)
+		{
+			throw std::system_error(ErrorCode, fmt::format("Failed to create directories for '{}'", Dir.string()));
+		}
+		return true;
 	}
-	return WasCreated;
+	return false;
 }
 
 bool