81 lines · cpp
1//===-- LockFileBase.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/LockFileBase.h"10 11using namespace lldb;12using namespace lldb_private;13 14static Status AlreadyLocked() {15 return Status::FromErrorString("Already locked");16}17 18static Status NotLocked() { return Status::FromErrorString("Not locked"); }19 20LockFileBase::LockFileBase(int fd)21 : m_fd(fd), m_locked(false), m_start(0), m_len(0) {}22 23bool LockFileBase::IsLocked() const { return m_locked; }24 25Status LockFileBase::WriteLock(const uint64_t start, const uint64_t len) {26 return DoLock([&](const uint64_t start,27 const uint64_t len) { return DoWriteLock(start, len); },28 start, len);29}30 31Status LockFileBase::TryWriteLock(const uint64_t start, const uint64_t len) {32 return DoLock([&](const uint64_t start,33 const uint64_t len) { return DoTryWriteLock(start, len); },34 start, len);35}36 37Status LockFileBase::ReadLock(const uint64_t start, const uint64_t len) {38 return DoLock([&](const uint64_t start,39 const uint64_t len) { return DoReadLock(start, len); },40 start, len);41}42 43Status LockFileBase::TryReadLock(const uint64_t start, const uint64_t len) {44 return DoLock([&](const uint64_t start,45 const uint64_t len) { return DoTryReadLock(start, len); },46 start, len);47}48 49Status LockFileBase::Unlock() {50 if (!IsLocked())51 return NotLocked();52 53 Status error = DoUnlock();54 if (error.Success()) {55 m_locked = false;56 m_start = 0;57 m_len = 0;58 }59 return error;60}61 62bool LockFileBase::IsValidFile() const { return m_fd != -1; }63 64Status LockFileBase::DoLock(const Locker &locker, const uint64_t start,65 const uint64_t len) {66 if (!IsValidFile())67 return Status::FromErrorString("File is invalid");68 69 if (IsLocked())70 return AlreadyLocked();71 72 Status error = locker(start, len);73 if (error.Success()) {74 m_locked = true;75 m_start = start;76 m_len = len;77 }78 79 return error;80}81