| 397 | } |
| 398 | |
| 399 | bool zeroFillFile(int fd, size_t startPos, size_t size) { |
| 400 | if (fd < 0) { |
| 401 | return false; |
| 402 | } |
| 403 | |
| 404 | if (lseek(fd, static_cast<off_t>(startPos), SEEK_SET) < 0) { |
| 405 | MMKVError("fail to lseek fd[%d], error:%s", fd, strerror(errno)); |
| 406 | return false; |
| 407 | } |
| 408 | |
| 409 | static const char zeros[4096] = {}; |
| 410 | while (size >= sizeof(zeros)) { |
| 411 | if (write(fd, zeros, sizeof(zeros)) < 0) { |
| 412 | MMKVError("fail to write fd[%d], error:%s", fd, strerror(errno)); |
| 413 | return false; |
| 414 | } |
| 415 | size -= sizeof(zeros); |
| 416 | } |
| 417 | if (size > 0) { |
| 418 | if (write(fd, zeros, size) < 0) { |
| 419 | MMKVError("fail to write fd[%d], error:%s", fd, strerror(errno)); |
| 420 | return false; |
| 421 | } |
| 422 | } |
| 423 | return true; |
| 424 | } |
| 425 | |
| 426 | #ifndef MMKV_APPLE |
| 427 | |