return true if the given two files are the same, false otherwise */
| 41 | |
| 42 | /* return true if the given two files are the same, false otherwise */ |
| 43 | static bool is_same(const char *file1, const char *file2) |
| 44 | { |
| 45 | int fd1, fd2; |
| 46 | struct stat st1, st2; |
| 47 | void *map1, *map2; |
| 48 | bool ret = false; |
| 49 | |
| 50 | fd1 = open(file1, O_RDONLY); |
| 51 | if (fd1 < 0) |
| 52 | return ret; |
| 53 | |
| 54 | fd2 = open(file2, O_RDONLY); |
| 55 | if (fd2 < 0) |
| 56 | goto close1; |
| 57 | |
| 58 | ret = fstat(fd1, &st1); |
| 59 | if (ret) |
| 60 | goto close2; |
| 61 | ret = fstat(fd2, &st2); |
| 62 | if (ret) |
| 63 | goto close2; |
| 64 | |
| 65 | if (st1.st_size != st2.st_size) |
| 66 | goto close2; |
| 67 | |
| 68 | map1 = mmap(NULL, st1.st_size, PROT_READ, MAP_PRIVATE, fd1, 0); |
| 69 | if (map1 == MAP_FAILED) |
| 70 | goto close2; |
| 71 | |
| 72 | map2 = mmap(NULL, st2.st_size, PROT_READ, MAP_PRIVATE, fd2, 0); |
| 73 | if (map2 == MAP_FAILED) |
| 74 | goto close2; |
| 75 | |
| 76 | if (bcmp(map1, map2, st1.st_size)) |
| 77 | goto close2; |
| 78 | |
| 79 | ret = true; |
| 80 | close2: |
| 81 | close(fd2); |
| 82 | close1: |
| 83 | close(fd1); |
| 84 | |
| 85 | return ret; |
| 86 | } |
| 87 | |
| 88 | /* |
| 89 | * Create the parent directory of the given path. |