blob: d8b2a61008335d3040ed7c5c27912677183771ee (
plain)
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
|
#include <u.h>
#include <libn.h>
#include <sys/mman.h>
mmap·Reader
mmap·open(byte *filename)
{
int fd;
int err;
void *buf;
Stream *s;
io·Stat st;
s = io·open(filename, "r");
fd = io·fd(s);
err = io·stat(s, &st);
if (err) {
errorf("file stat: error code %d", err);
goto ERROR;
}
buf = mmap(nil, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
if (!buf) {
errorf("mmap: failed");
goto ERROR;
}
// NOTE: posix systems require that reference kept to mmap file after fd is closed
io·close(s);
return (mmap·Reader){.len=st.st_size, .buf=buf};
ERROR:
io·close(s);
return (mmap·Reader){ 0 };
}
error
mmap·close(mmap·Reader rdr)
{
munmap(rdr.buf, rdr.len);
return 0;
}
|