1 /* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
2 file Copyright.txt or https://cmake.org/licensing for details. */
3 #include <cerrno> // errno
4 #include <cstdio> // SEEK_SET
9 #include "cmFileLock.h"
10 #include "cmSystemTools.h"
12 cmFileLock::cmFileLock() = default;
14 cmFileLockResult cmFileLock::Release()
16 if (this->Filename.empty()) {
17 return cmFileLockResult::MakeOk();
19 const int lockResult = this->LockFile(F_SETLK, F_UNLCK);
26 if (lockResult == 0) {
27 return cmFileLockResult::MakeOk();
29 return cmFileLockResult::MakeSystem();
32 cmFileLockResult cmFileLock::OpenFile()
34 this->File = ::open(this->Filename.c_str(), O_RDWR);
35 if (this->File == -1) {
36 return cmFileLockResult::MakeSystem();
38 return cmFileLockResult::MakeOk();
41 cmFileLockResult cmFileLock::LockWithoutTimeout()
43 if (this->LockFile(F_SETLKW, F_WRLCK) == -1) {
44 return cmFileLockResult::MakeSystem();
46 return cmFileLockResult::MakeOk();
49 cmFileLockResult cmFileLock::LockWithTimeout(unsigned long seconds)
52 if (this->LockFile(F_SETLK, F_WRLCK) == -1) {
53 if (errno != EACCES && errno != EAGAIN) {
54 return cmFileLockResult::MakeSystem();
57 return cmFileLockResult::MakeOk();
60 return cmFileLockResult::MakeTimeout();
63 cmSystemTools::Delay(1000);
67 int cmFileLock::LockFile(int cmd, int type) const
71 lock.l_len = 0; // lock all bytes
72 lock.l_pid = 0; // unused (for F_GETLK only)
73 lock.l_type = static_cast<short>(type); // exclusive lock
74 lock.l_whence = SEEK_SET;
75 return ::fcntl(this->File, cmd, &lock);