76 lines · cpp
1//===-- LockFileWindows.cpp -----------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "lldb/Host/windows/LockFileWindows.h"10 11#include <io.h>12 13using namespace lldb;14using namespace lldb_private;15 16static Status fileLock(HANDLE file_handle, DWORD flags, const uint64_t start,17 const uint64_t len) {18 if (start != 0)19 return Status::FromErrorString(20 "Non-zero start lock regions are not supported");21 22 OVERLAPPED overlapped = {};23 24 if (!::LockFileEx(file_handle, flags, 0, len, 0, &overlapped) &&25 ::GetLastError() != ERROR_IO_PENDING)26 return Status(::GetLastError(), eErrorTypeWin32);27 28 DWORD bytes;29 if (!::GetOverlappedResult(file_handle, &overlapped, &bytes, TRUE))30 return Status(::GetLastError(), eErrorTypeWin32);31 32 return Status();33}34 35LockFileWindows::LockFileWindows(int fd)36 : LockFileBase(fd), m_file(reinterpret_cast<HANDLE>(_get_osfhandle(fd))) {}37 38LockFileWindows::~LockFileWindows() { Unlock(); }39 40bool LockFileWindows::IsValidFile() const {41 return LockFileBase::IsValidFile() && m_file != INVALID_HANDLE_VALUE;42}43 44Status LockFileWindows::DoWriteLock(const uint64_t start, const uint64_t len) {45 return fileLock(m_file, LOCKFILE_EXCLUSIVE_LOCK, start, len);46}47 48Status LockFileWindows::DoTryWriteLock(const uint64_t start,49 const uint64_t len) {50 return fileLock(m_file, LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY,51 start, len);52}53 54Status LockFileWindows::DoReadLock(const uint64_t start, const uint64_t len) {55 return fileLock(m_file, 0, start, len);56}57 58Status LockFileWindows::DoTryReadLock(const uint64_t start,59 const uint64_t len) {60 return fileLock(m_file, LOCKFILE_FAIL_IMMEDIATELY, start, len);61}62 63Status LockFileWindows::DoUnlock() {64 OVERLAPPED overlapped = {};65 66 if (!::UnlockFileEx(m_file, 0, m_len, 0, &overlapped) &&67 ::GetLastError() != ERROR_IO_PENDING)68 return Status(::GetLastError(), eErrorTypeWin32);69 70 DWORD bytes;71 if (!::GetOverlappedResult(m_file, &overlapped, &bytes, TRUE))72 return Status(::GetLastError(), eErrorTypeWin32);73 74 return Status();75}76