diff options
Diffstat (limited to 'src/zenutil/basicfile.cpp')
| -rw-r--r-- | src/zenutil/basicfile.cpp | 94 |
1 files changed, 84 insertions, 10 deletions
diff --git a/src/zenutil/basicfile.cpp b/src/zenutil/basicfile.cpp index 1dce71e60..7d0edaa5d 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) { @@ -588,6 +587,8 @@ 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 +663,79 @@ 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); +} + +////////////////////////////////////////////////////////////////////////// + /* ___________ __ \__ ___/___ _______/ |_ ______ |