1 files changed, 171 insertions, 0 deletions
diff --git a/src/zen/cmds/hash_cmd.cpp b/src/zen/cmds/hash_cmd.cpp
new file mode 100644
index 000000000..d1f7a1975
--- /dev/null
+++ b/src/zen/cmds/hash_cmd.cpp
@@ -0,0 +1,171 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include "hash_cmd.h"
+
+#include <zencore/blake3.h>
+#include <zencore/logging.h>
+#include <zencore/string.h>
+#include <zencore/timer.h>
+
+#if ZEN_PLATFORM_WINDOWS
+#	include <ppl.h>
+#endif
+
+namespace zen {
+
+////////////////////////////////////////////////////////////////////////////////
+
+#if ZEN_PLATFORM_LINUX || ZEN_PLATFORM_MAC
+
+namespace Concurrency {
+
+	template<typename IterType, typename LambdaType>
+	void parallel_for_each(IterType Cursor, IterType End, const LambdaType& Lambda)
+	{
+		for (; Cursor < End; ++Cursor)
+		{
+			Lambda(*Cursor);
+		}
+	}
+
+	template<typename T>
+	struct combinable
+	{
+		combinable<T>& local() { return *this; }
+
+		void operator+=(T Rhs) { Value += Rhs; }
+
+		template<typename LambdaType>
+		void combine_each(const LambdaType& Lambda)
+		{
+			Lambda(Value);
+		}
+
+		T Value = 0;
+	};
+
+}  // namespace Concurrency
+
+#endif	// ZEN_PLATFORM_LINUX|MAC
+
+////////////////////////////////////////////////////////////////////////////////
+
+HashCommand::HashCommand()
+{
+	m_Options.add_options()("d,dir", "Directory to scan", cxxopts::value<std::string>(m_ScanDirectory))(
+		"o,output",
+		"Output file",
+		cxxopts::value<std::string>(m_OutputFile));
+}
+
+HashCommand::~HashCommand() = default;
+
+int
+HashCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
+{
+	ZEN_UNUSED(GlobalOptions);
+
+	if (!ParseOptions(argc, argv))
+	{
+		return 0;
+	}
+
+	bool valid = m_ScanDirectory.length();
+
+	if (!valid)
+		throw zen::OptionParseException("Hash command requires a directory to scan");
+
+	// Gather list of files to process
+
+	ZEN_CONSOLE("Gathering files from {}", m_ScanDirectory);
+
+	struct FileEntry
+	{
+		std::filesystem::path FilePath;
+		zen::BLAKE3			  FileHash;
+	};
+
+	std::vector<FileEntry> FileList;
+	uint64_t			   FileBytes = 0;
+
+	std::filesystem::path ScanDirectoryPath{m_ScanDirectory};
+
+	for (const std::filesystem::directory_entry& Entry : std::filesystem::recursive_directory_iterator(ScanDirectoryPath))
+	{
+		if (Entry.is_regular_file())
+		{
+			FileList.push_back({Entry.path()});
+			FileBytes += Entry.file_size();
+		}
+	}
+
+	ZEN_CONSOLE("Gathered {} files, total size {}", FileList.size(), zen::NiceBytes(FileBytes));
+
+	Concurrency::combinable<uint64_t> TotalBytes;
+
+	auto hashFile = [&](FileEntry& File) {
+		InternalFile InputFile;
+		InputFile.OpenRead(File.FilePath);
+		const uint8_t* DataPointer = (const uint8_t*)InputFile.MemoryMapFile();
+		const size_t   DataSize	   = InputFile.GetFileSize();
+
+		File.FileHash = zen::BLAKE3::HashMemory(DataPointer, DataSize);
+
+		TotalBytes.local() += DataSize;
+	};
+
+	// Process them as quickly as possible
+
+	zen::Stopwatch Timer;
+
+#if 1
+	Concurrency::parallel_for_each(begin(FileList), end(FileList), [&](auto& file) { hashFile(file); });
+#else
+	for (const auto& file : FileList)
+	{
+		hashFile(file);
+	}
+#endif
+
+	size_t TotalByteCount = 0;
+
+	TotalBytes.combine_each([&](size_t Total) { TotalByteCount += Total; });
+
+	const uint64_t ElapsedMs = Timer.GetElapsedTimeMs();
+	ZEN_CONSOLE("Scanned {} files in {}", FileList.size(), zen::NiceTimeSpanMs(ElapsedMs));
+	ZEN_CONSOLE("Total bytes {} ({})", zen::NiceBytes(TotalByteCount), zen::NiceByteRate(TotalByteCount, ElapsedMs));
+
+	InternalFile Output;
+
+	if (m_OutputFile.empty())
+	{
+		// TEMPORARY -- should properly open stdout
+		Output.OpenWrite("CONOUT$", false);
+	}
+	else
+	{
+		Output.OpenWrite(m_OutputFile, true);
+	}
+
+	zen::ExtendableStringBuilder<256> Line;
+
+	uint64_t CurrentOffset = 0;
+
+	for (const auto& File : FileList)
+	{
+		Line.Append(File.FilePath.generic_u8string().c_str());
+		Line.Append(',');
+		File.FileHash.ToHexString(Line);
+		Line.Append('\n');
+
+		Output.Write(Line.Data(), Line.Size(), CurrentOffset);
+		CurrentOffset += Line.Size();
+
+		Line.Reset();
+	}
+
+	// TODO: implement snapshot enumeration and display
+	return 0;
+}
+
+}  // namespace zen