| Elliott Hughes | 5704c42 | 2016-01-25 18:06:24 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in |
| 12 | * the documentation and/or other materials provided with the |
| 13 | * distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 16 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 17 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 18 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 19 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 21 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| 22 | * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 23 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 24 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 25 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 26 | * SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | #include <unistd.h> |
| 30 | |
| 31 | #include <errno.h> |
| 32 | #include <fcntl.h> |
| 33 | #include <string.h> |
| 34 | |
| 35 | int lockf64(int fd, int cmd, off64_t length) { |
| 36 | // Translate POSIX lockf into fcntl. |
| Elliott Hughes | d4ae54f | 2016-01-26 14:32:55 -0800 | [diff] [blame] | 37 | struct flock64 fl; |
| Elliott Hughes | 5704c42 | 2016-01-25 18:06:24 -0800 | [diff] [blame] | 38 | memset(&fl, 0, sizeof(fl)); |
| 39 | fl.l_whence = SEEK_CUR; |
| 40 | fl.l_start = 0; |
| 41 | fl.l_len = length; |
| 42 | |
| 43 | if (cmd == F_ULOCK) { |
| 44 | fl.l_type = F_UNLCK; |
| 45 | cmd = F_SETLK64; |
| 46 | return fcntl(fd, F_SETLK64, &fl); |
| 47 | } |
| 48 | |
| 49 | if (cmd == F_LOCK) { |
| 50 | fl.l_type = F_WRLCK; |
| 51 | return fcntl(fd, F_SETLKW64, &fl); |
| 52 | } |
| 53 | |
| 54 | if (cmd == F_TLOCK) { |
| 55 | fl.l_type = F_WRLCK; |
| 56 | return fcntl(fd, F_SETLK64, &fl); |
| 57 | } |
| 58 | |
| 59 | if (cmd == F_TEST) { |
| 60 | fl.l_type = F_RDLCK; |
| 61 | if (fcntl(fd, F_GETLK64, &fl) == -1) return -1; |
| 62 | if (fl.l_type == F_UNLCK || fl.l_pid == getpid()) return 0; |
| 63 | errno = EACCES; |
| 64 | return -1; |
| 65 | } |
| 66 | |
| 67 | errno = EINVAL; |
| 68 | return -1; |
| 69 | } |
| 70 | |
| 71 | int lockf(int fd, int cmd, off_t length) { |
| 72 | return lockf64(fd, cmd, length); |
| 73 | } |