Merge branch 'main' of https://github.com/EpicGames/zen

1 files changed, 107 insertions, 19 deletions

diff --git a/src/zenutil/basicfile.cpp b/src/zenutil/basicfile.cpp
index 1dce71e60..819d0805d 100644
--- a/src/zenutil/basicfile.cpp
+++ b/src/zenutil/basicfile.cpp
@@ -76,16 +76,15 @@ BasicFile::Open(const std::filesystem::path& FileName, Mode InMode, std::error_c
 
 	const DWORD dwShareMode = FILE_SHARE_READ | (EnumHasAllFlags(InMode, Mode::kPreventWrite) ? 0 : FILE_SHARE_WRITE) |
 							  (EnumHasAllFlags(InMode, Mode::kPreventDelete) ? 0 : FILE_SHARE_DELETE);
-	const DWORD dwFlagsAndAttributes =
-		FILE_ATTRIBUTE_NORMAL | (EnumHasAllFlags(InMode, Mode::kDeleteOnClose) ? FILE_FLAG_DELETE_ON_CLOSE : 0);
-	const HANDLE hTemplateFile = nullptr;
-	const HANDLE FileHandle	   = CreateFile(FileName.c_str(),
-											dwDesiredAccess,
-											dwShareMode,
-											/* lpSecurityAttributes */ nullptr,
-											dwCreationDisposition,
-											dwFlagsAndAttributes,
-											hTemplateFile);
+	const DWORD	 dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
+	const HANDLE hTemplateFile		  = nullptr;
+	const HANDLE FileHandle			  = CreateFile(FileName.c_str(),
+										   dwDesiredAccess,
+										   dwShareMode,
+										   /* lpSecurityAttributes */ nullptr,
+										   dwCreationDisposition,
+										   dwFlagsAndAttributes,
+										   hTemplateFile);
 
 	if (FileHandle == INVALID_HANDLE_VALUE)
 	{
@@ -192,7 +191,8 @@ BasicFile::Read(void* Data, uint64_t BytesToRead, uint64_t FileOffset)
 
 		if (!Success)
 		{
-			ThrowLastError(fmt::format("Failed to read from file '{}'", zen::PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowLastError(fmt::format("Failed to read from file '{}'", zen::PathFromHandle(m_FileHandle, Dummy)));
 		}
 
 		BytesToRead -= NumberOfBytesToRead;
@@ -325,7 +325,8 @@ BasicFile::Write(const void* Data, uint64_t Size, uint64_t Offset)
 
 	if (Ec)
 	{
-		throw std::system_error(Ec, fmt::format("Failed to write to file '{}'", zen::PathFromHandle(m_FileHandle)));
+		std::error_code Dummy;
+		throw std::system_error(Ec, fmt::format("Failed to write to file '{}'", zen::PathFromHandle(m_FileHandle, Dummy)));
 	}
 }
 
@@ -357,7 +358,8 @@ BasicFile::FileSize()
 		int Error = zen::GetLastError();
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to get file size from file '{}'", PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error, fmt::format("Failed to get file size from file '{}'", PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 	return uint64_t(liFileSize.QuadPart);
@@ -367,7 +369,8 @@ BasicFile::FileSize()
 	struct stat Stat;
 	if (fstat(Fd, &Stat) == -1)
 	{
-		ThrowSystemError(GetLastError(), fmt::format("Failed to get file size from file '{}'", PathFromHandle(m_FileHandle)));
+		std::error_code Dummy;
+		ThrowSystemError(GetLastError(), fmt::format("Failed to get file size from file '{}'", PathFromHandle(m_FileHandle, Dummy)));
 	}
 	return uint64_t(Stat.st_size);
 #endif
@@ -414,7 +417,9 @@ BasicFile::SetFileSize(uint64_t FileSize)
 		int Error = zen::GetLastError();
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to set file pointer to {} for file {}", FileSize, PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error,
+							 fmt::format("Failed to set file pointer to {} for file {}", FileSize, PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 	OK = ::SetEndOfFile(m_FileHandle);
@@ -423,7 +428,9 @@ BasicFile::SetFileSize(uint64_t FileSize)
 		int Error = zen::GetLastError();
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to set end of file to {} for file {}", FileSize, PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error,
+							 fmt::format("Failed to set end of file to {} for file {}", FileSize, PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 #elif ZEN_PLATFORM_MAC
@@ -433,7 +440,9 @@ BasicFile::SetFileSize(uint64_t FileSize)
 		int Error = zen::GetLastError();
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to set truncate file to {} for file {}", FileSize, PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error,
+							 fmt::format("Failed to set truncate file to {} for file {}", FileSize, PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 #else
@@ -443,7 +452,9 @@ BasicFile::SetFileSize(uint64_t FileSize)
 		int Error = zen::GetLastError();
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to set truncate file to {} for file {}", FileSize, PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error,
+							 fmt::format("Failed to set truncate file to {} for file {}", FileSize, PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 	if (FileSize > 0)
@@ -451,7 +462,9 @@ BasicFile::SetFileSize(uint64_t FileSize)
 		int Error = posix_fallocate64(Fd, 0, (off64_t)FileSize);
 		if (Error)
 		{
-			ThrowSystemError(Error, fmt::format("Failed to allocate space of {} for file {}", FileSize, PathFromHandle(m_FileHandle)));
+			std::error_code Dummy;
+			ThrowSystemError(Error,
+							 fmt::format("Failed to allocate space of {} for file {}", FileSize, PathFromHandle(m_FileHandle, Dummy)));
 		}
 	}
 #endif
@@ -588,6 +601,8 @@ LockFile::Update(CbObject Payload, std::error_code& Ec)
 	BasicFile::Write(Payload.GetBuffer(), 0, Ec);
 }
 
+//////////////////////////////////////////////////////////////////////////
+
 BasicFileBuffer::BasicFileBuffer(BasicFile& Base, uint64_t BufferSize)
 : m_Base(Base)
 , m_Buffer(nullptr)
@@ -662,6 +677,79 @@ BasicFileBuffer::MakeView(uint64_t Size, uint64_t FileOffset)
 	return MemoryView(m_Buffer + (FileOffset - m_BufferStart), Size);
 }
 
+//////////////////////////////////////////////////////////////////////////
+
+BasicFileWriter::BasicFileWriter(BasicFile& Base, uint64_t BufferSize)
+: m_Base(Base)
+, m_Buffer(nullptr)
+, m_BufferSize(BufferSize)
+, m_BufferStart(0)
+, m_BufferEnd(0)
+{
+	m_Buffer = (uint8_t*)Memory::Alloc(m_BufferSize);
+}
+
+BasicFileWriter::~BasicFileWriter()
+{
+	Flush();
+	Memory::Free(m_Buffer);
+}
+
+void
+BasicFileWriter::Write(void* Data, uint64_t Size, uint64_t FileOffset)
+{
+	if (m_Buffer == nullptr || (Size >= m_BufferSize))
+	{
+		m_Base.Write(Data, Size, FileOffset);
+		return;
+	}
+
+	// Note that this only supports buffering of sequential writes!
+
+	if (FileOffset != m_BufferEnd)
+	{
+		Flush();
+		m_BufferStart = m_BufferEnd = FileOffset;
+	}
+
+	while (Size)
+	{
+		const uint64_t RemainingBufferCapacity = m_BufferStart + m_BufferSize - m_BufferEnd;
+		const uint64_t BlockWriteBytes		   = Min(RemainingBufferCapacity, Size);
+		const uint64_t BufferWriteOffset	   = FileOffset - m_BufferStart;
+
+		ZEN_ASSERT_SLOW(BufferWriteOffset < m_BufferSize);
+		ZEN_ASSERT_SLOW((BufferWriteOffset + BlockWriteBytes) <= m_BufferSize);
+
+		memcpy(m_Buffer + BufferWriteOffset, Data, BlockWriteBytes);
+
+		Size -= BlockWriteBytes;
+		m_BufferEnd += BlockWriteBytes;
+		FileOffset += BlockWriteBytes;
+
+		if ((m_BufferEnd - m_BufferStart) == m_BufferSize)
+		{
+			Flush();
+		}
+	}
+}
+
+void
+BasicFileWriter::Flush()
+{
+	const uint64_t BufferedBytes = m_BufferEnd - m_BufferStart;
+
+	if (BufferedBytes == 0)
+		return;
+
+	const uint64_t WriteOffset = m_BufferStart;
+	m_BufferStart			   = m_BufferEnd;
+
+	m_Base.Write(m_Buffer, BufferedBytes, WriteOffset);
+}
+
+//////////////////////////////////////////////////////////////////////////
+
 /*
 		___________              __
 		\__    ___/___   _______/  |_  ______