1 //===-- LockFilePosix.cpp ---------------------------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "lldb/Host/posix/LockFilePosix.h"
11
12 #include <fcntl.h>
13
14 using namespace lldb;
15 using namespace lldb_private;
16
17 namespace
18 {
19
fileLock(int fd,int cmd,int lock_type,const uint64_t start,const uint64_t len)20 Error fileLock (int fd, int cmd, int lock_type, const uint64_t start, const uint64_t len)
21 {
22 struct flock fl;
23
24 fl.l_type = lock_type;
25 fl.l_whence = SEEK_SET;
26 fl.l_start = start;
27 fl.l_len = len;
28 fl.l_pid = ::getpid ();
29
30 Error error;
31 if (::fcntl (fd, cmd, &fl) == -1)
32 error.SetErrorToErrno ();
33
34 return error;
35 }
36
37 } // namespace
38
LockFilePosix(int fd)39 LockFilePosix::LockFilePosix (int fd)
40 : LockFileBase (fd)
41 {
42 }
43
~LockFilePosix()44 LockFilePosix::~LockFilePosix ()
45 {
46 Unlock ();
47 }
48
49 Error
DoWriteLock(const uint64_t start,const uint64_t len)50 LockFilePosix::DoWriteLock (const uint64_t start, const uint64_t len)
51 {
52 return fileLock (m_fd, F_SETLKW, F_WRLCK, start, len);
53 }
54
55 Error
DoTryWriteLock(const uint64_t start,const uint64_t len)56 LockFilePosix::DoTryWriteLock (const uint64_t start, const uint64_t len)
57 {
58 return fileLock (m_fd, F_SETLK, F_WRLCK, start, len);
59 }
60
61 Error
DoReadLock(const uint64_t start,const uint64_t len)62 LockFilePosix::DoReadLock (const uint64_t start, const uint64_t len)
63 {
64 return fileLock (m_fd, F_SETLKW, F_RDLCK, start, len);
65 }
66
67 Error
DoTryReadLock(const uint64_t start,const uint64_t len)68 LockFilePosix::DoTryReadLock (const uint64_t start, const uint64_t len)
69 {
70 return fileLock (m_fd, F_SETLK, F_RDLCK, start, len);
71 }
72
73 Error
DoUnlock()74 LockFilePosix::DoUnlock ()
75 {
76 return fileLock (m_fd, F_SETLK, F_UNLCK, m_start, m_len);
77 }
78