ADTarm-ehast-experimentalenumforall-pointer-decayjacob/cs343-translationnew-astnew-ast-unique-exprpthread-emulationqualifiedEnum
Last change
on this file since f100a83 was
f100a83,
checked in by Thierry Delisle <tdelisle@…>, 5 years ago
|
Updated io_uring example to be less hacky
|
-
Property mode set to
100644
|
File size:
1.4 KB
|
Line | |
---|
1 | #include <fcntl.h> |
---|
2 | #include <liburing.h> |
---|
3 | #include <stdio.h> |
---|
4 | #include <unistd.h> |
---|
5 | |
---|
6 | struct io_uring ring; |
---|
7 | |
---|
8 | int main(int argc, char * argv[]) { |
---|
9 | if(argc != 2) { |
---|
10 | printf("usage: %s FILE - prints file to console.\n", argv[0]); |
---|
11 | return 1; |
---|
12 | } |
---|
13 | |
---|
14 | int fd = open(argv[1], 0); |
---|
15 | if(fd < 0) { |
---|
16 | printf("Could not open file %s.\n", argv[1]); |
---|
17 | return 2; |
---|
18 | } |
---|
19 | |
---|
20 | /* prep the array */ |
---|
21 | char data[512]; |
---|
22 | struct iovec iov = { data, 512 }; |
---|
23 | |
---|
24 | /* init liburing */ |
---|
25 | io_uring_queue_init(256, &ring, 0); |
---|
26 | |
---|
27 | /* declare required structs */ |
---|
28 | struct io_uring_sqe * sqe; |
---|
29 | struct io_uring_cqe * cqe; |
---|
30 | |
---|
31 | /* get an sqe and fill in a READV operation */ |
---|
32 | sqe = io_uring_get_sqe(&ring); |
---|
33 | io_uring_prep_readv(sqe, fd, &iov, 1, 0); |
---|
34 | |
---|
35 | sqe->user_data = data; |
---|
36 | |
---|
37 | /* tell the kernel we have an sqe ready for consumption */ |
---|
38 | io_uring_submit(&ring); |
---|
39 | |
---|
40 | /* wait for the sqe to complete */ |
---|
41 | int ret = io_uring_wait_cqe(&ring, &cqe); |
---|
42 | |
---|
43 | /* read and process cqe event */ |
---|
44 | if(ret == 0) { |
---|
45 | char * out = cqe->user_data; |
---|
46 | signed int len = cqe->res; |
---|
47 | io_uring_cqe_seen(&ring, cqe); |
---|
48 | |
---|
49 | if(len > 0) { |
---|
50 | printf("%.*s", len, out); |
---|
51 | } |
---|
52 | } |
---|
53 | else { |
---|
54 | printf("%d\n", ret); |
---|
55 | io_uring_cqe_seen(&ring, cqe); |
---|
56 | } |
---|
57 | |
---|
58 | io_uring_queue_exit(&ring); |
---|
59 | |
---|
60 | close(fd); |
---|
61 | } |
---|
Note: See
TracBrowser
for help on using the repository browser.