CMake/Source/cmFileLockUnix.cxx
Ruslan Baratov 97841dad2b file: Use 'long' to represent the parsed LOCK TIMEOUT value
Convert the StringToInt helper into a StringToLong helper with a 'long'
result type.  This will make the helper more useful to other callers
that want to use strtol.

While at it, also check errno after calling strtol in case the
conversion fails with a range error.
2014-12-05 12:59:37 -05:00

103 lines
2.2 KiB
C++

/*============================================================================
CMake - Cross Platform Makefile Generator
Copyright 2014 Ruslan Baratov
Distributed under the OSI-approved BSD License (the "License");
see accompanying file Copyright.txt for details.
This software is distributed WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the License for more information.
============================================================================*/
#include "cmFileLock.h"
#include <errno.h> // errno
#include <stdio.h> // SEEK_SET
#include <fcntl.h>
#include "cmSystemTools.h"
cmFileLock::cmFileLock(): File(-1)
{
}
cmFileLockResult cmFileLock::Release()
{
if (this->Filename.empty())
{
return cmFileLockResult::MakeOk();
}
const int lockResult = this->LockFile(F_SETLK, F_UNLCK);
this->Filename = "";
if (lockResult == 0)
{
return cmFileLockResult::MakeOk();
}
else
{
return cmFileLockResult::MakeSystem();
}
}
cmFileLockResult cmFileLock::OpenFile()
{
this->File = ::open(this->Filename.c_str(), O_RDWR);
if (this->File == -1)
{
return cmFileLockResult::MakeSystem();
}
else
{
return cmFileLockResult::MakeOk();
}
}
cmFileLockResult cmFileLock::LockWithoutTimeout()
{
if (this->LockFile(F_SETLKW, F_WRLCK) == -1)
{
return cmFileLockResult::MakeSystem();
}
else
{
return cmFileLockResult::MakeOk();
}
}
cmFileLockResult cmFileLock::LockWithTimeout(unsigned long seconds)
{
while (true)
{
if (this->LockFile(F_SETLK, F_WRLCK) == -1)
{
if (errno != EACCES && errno != EAGAIN)
{
return cmFileLockResult::MakeSystem();
}
}
else
{
return cmFileLockResult::MakeOk();
}
if (seconds == 0)
{
return cmFileLockResult::MakeTimeout();
}
--seconds;
cmSystemTools::Delay(1000);
}
}
int cmFileLock::LockFile(int cmd, int type)
{
struct ::flock lock;
lock.l_start = 0;
lock.l_len = 0; // lock all bytes
lock.l_pid = 0; // unused (for F_GETLK only)
lock.l_type = static_cast<short>(type); // exclusive lock
lock.l_whence = SEEK_SET;
return ::fcntl(this->File, cmd, &lock);
}