Junio C Hamano | 4050c0d | 2005-12-05 11:54:29 -0800 | [diff] [blame] | 1 | #include "../git-compat-util.h" |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 2 | |
Shawn O. Pearce | d677912 | 2006-12-24 00:45:37 -0500 | [diff] [blame] | 3 | void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset) |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 4 | { |
Shawn O. Pearce | 8e55442 | 2006-12-24 00:45:47 -0500 | [diff] [blame] | 5 | size_t n = 0; |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 6 | |
Junio C Hamano | f48000f | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 7 | if (start != NULL || !(flags & MAP_PRIVATE)) |
Shawn O. Pearce | d677912 | 2006-12-24 00:45:37 -0500 | [diff] [blame] | 8 | die("Invalid usage of mmap when built with NO_MMAP"); |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 9 | |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 10 | start = xmalloc(length); |
Junio C Hamano | f48000f | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 11 | if (start == NULL) { |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 12 | errno = ENOMEM; |
| 13 | return MAP_FAILED; |
| 14 | } |
| 15 | |
Junio C Hamano | f48000f | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 16 | while (n < length) { |
Shawn O. Pearce | 8e55442 | 2006-12-24 00:45:47 -0500 | [diff] [blame] | 17 | ssize_t count = pread(fd, (char *)start + n, length - n, offset + n); |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 18 | |
Junio C Hamano | f48000f | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 19 | if (count == 0) { |
Shawn O. Pearce | 8e55442 | 2006-12-24 00:45:47 -0500 | [diff] [blame] | 20 | memset((char *)start+n, 0, length-n); |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 21 | break; |
| 22 | } |
| 23 | |
Junio C Hamano | f48000f | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 24 | if (count < 0) { |
Shawn O. Pearce | 8e55442 | 2006-12-24 00:45:47 -0500 | [diff] [blame] | 25 | if (errno == EAGAIN || errno == EINTR) |
| 26 | continue; |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 27 | free(start); |
| 28 | errno = EACCES; |
| 29 | return MAP_FAILED; |
| 30 | } |
| 31 | |
| 32 | n += count; |
| 33 | } |
| 34 | |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 35 | return start; |
| 36 | } |
| 37 | |
Shawn O. Pearce | d677912 | 2006-12-24 00:45:37 -0500 | [diff] [blame] | 38 | int git_munmap(void *start, size_t length) |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 39 | { |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 40 | free(start); |
Johannes Schindelin | 730d48a | 2005-10-08 15:54:36 -0700 | [diff] [blame] | 41 | return 0; |
| 42 | } |