llvm-project/lldb/source/Host/common/LockFileBase.cpp

125 lines
2.4 KiB
C++

//===-- LockFileBase.cpp ----------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Host/LockFileBase.h"
using namespace lldb;
using namespace lldb_private;
namespace
{
Error
AlreadyLocked ()
{
return Error ("Already locked");
}
Error
NotLocked ()
{
return Error ("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;
}
Error
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);
}
Error
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);
}
Error
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);
}
Error
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);
}
Error
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;
}
Error
LockFileBase::DoLock (const Locker &locker, const uint64_t start, const uint64_t len)
{
if (!IsValidFile ())
return Error("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;
}