LockFileBase.cpp
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//===-- LockFileBase.cpp ----------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/Host/LockFileBase.h"
using namespace lldb;
using namespace lldb_private;
namespace {
Status AlreadyLocked() { return Status("Already locked"); }
Status NotLocked() { return Status("Not locked"); }
}
LockFileBase::LockFileBase(int fd)
: m_fd(fd), m_locked(false), m_start(0), m_len(0) {}
bool LockFileBase::IsLocked() const { return m_locked; }
Status LockFileBase::WriteLock(const uint64_t start, const uint64_t len) {
return DoLock([&](const uint64_t start,
const uint64_t len) { return DoWriteLock(start, len); },
start, len);
}
Status LockFileBase::TryWriteLock(const uint64_t start, const uint64_t len) {
return DoLock([&](const uint64_t start,
const uint64_t len) { return DoTryWriteLock(start, len); },
start, len);
}
Status LockFileBase::ReadLock(const uint64_t start, const uint64_t len) {
return DoLock([&](const uint64_t start,
const uint64_t len) { return DoReadLock(start, len); },
start, len);
}
Status LockFileBase::TryReadLock(const uint64_t start, const uint64_t len) {
return DoLock([&](const uint64_t start,
const uint64_t len) { return DoTryReadLock(start, len); },
start, len);
}
Status LockFileBase::Unlock() {
if (!IsLocked())
return NotLocked();
const auto error = DoUnlock();
if (error.Success()) {
m_locked = false;
m_start = 0;
m_len = 0;
}
return error;
}
bool LockFileBase::IsValidFile() const { return m_fd != -1; }
Status LockFileBase::DoLock(const Locker &locker, const uint64_t start,
const uint64_t len) {
if (!IsValidFile())
return Status("File is invalid");
if (IsLocked())
return AlreadyLocked();
const auto error = locker(start, len);
if (error.Success()) {
m_locked = true;
m_start = start;
m_len = len;
}
return error;
}