1//===-- LockFilePosix.cpp -------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "lldb/Host/posix/LockFilePosix.h"
10
11#include "llvm/Support/Errno.h"
12
13#include <fcntl.h>
14#include <unistd.h>
15
16using namespace lldb;
17using namespace lldb_private;
18
19static Status fileLock(int fd, int cmd, int lock_type, const uint64_t start,
20 const uint64_t len) {
21 struct flock fl;
22
23 fl.l_type = lock_type;
24 fl.l_whence = SEEK_SET;
25 fl.l_start = start;
26 fl.l_len = len;
27 fl.l_pid = ::getpid();
28
29 Status error;
30 if (llvm::sys::RetryAfterSignal(Fail: -1, F&: ::fcntl, As: fd, As: cmd, As: &fl) == -1)
31 error.SetErrorToErrno();
32
33 return error;
34}
35
36LockFilePosix::LockFilePosix(int fd) : LockFileBase(fd) {}
37
38LockFilePosix::~LockFilePosix() { Unlock(); }
39
40Status LockFilePosix::DoWriteLock(const uint64_t start, const uint64_t len) {
41 return fileLock(fd: m_fd, F_SETLKW, F_WRLCK, start, len);
42}
43
44Status LockFilePosix::DoTryWriteLock(const uint64_t start, const uint64_t len) {
45 return fileLock(fd: m_fd, F_SETLK, F_WRLCK, start, len);
46}
47
48Status LockFilePosix::DoReadLock(const uint64_t start, const uint64_t len) {
49 return fileLock(fd: m_fd, F_SETLKW, F_RDLCK, start, len);
50}
51
52Status LockFilePosix::DoTryReadLock(const uint64_t start, const uint64_t len) {
53 return fileLock(fd: m_fd, F_SETLK, F_RDLCK, start, len);
54}
55
56Status LockFilePosix::DoUnlock() {
57 return fileLock(fd: m_fd, F_SETLK, F_UNLCK, start: m_start, len: m_len);
58}
59

source code of lldb/source/Host/posix/LockFilePosix.cpp