1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
#include "../git-compat-util.h"
void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
{
size_t n = 0;
if (start != NULL || flags != MAP_PRIVATE || prot != PROT_READ)
die("Invalid usage of mmap when built with NO_MMAP");
if (length == 0) {
errno = EINVAL;
return MAP_FAILED;
}
start = malloc(length);
if (!start) {
errno = ENOMEM;
return MAP_FAILED;
}
while (n < length) {
ssize_t count = xpread(fd, (char *)start + n, length - n, offset + n);
if (count == 0) {
memset((char *)start+n, 0, length-n);
break;
}
if (count < 0) {
free(start);
errno = EACCES;
return MAP_FAILED;
}
n += count;
}
return start;
}
int git_munmap(void *start, size_t length)
{
free(start);
return 0;
}
|
