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/*
* Description: -EAGAIN handling
*
*/
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include "liburing.h"
#define BLOCK 4096
#ifndef RWF_NOWAIT
#define RWF_NOWAIT 8
#endif
static int get_file_fd(void)
{
ssize_t ret;
char *buf;
int fd;
fd = open("testfile", O_RDWR | O_CREAT, 0644);
if (fd < 0) {
perror("open file");
return -1;
}
buf = malloc(BLOCK);
ret = write(fd, buf, BLOCK);
if (ret != BLOCK) {
if (ret < 0)
perror("write");
else
printf("Short write\n");
goto err;
}
fsync(fd);
if (posix_fadvise(fd, 0, 4096, POSIX_FADV_DONTNEED)) {
perror("fadvise");
err:
close(fd);
free(buf);
return -1;
}
free(buf);
return fd;
}
static void put_file_fd(int fd)
{
close(fd);
unlink("testfile");
}
int main(int argc, char *argv[])
{
struct io_uring ring;
struct io_uring_sqe *sqe;
struct io_uring_cqe *cqe;
struct iovec iov;
int ret, fd;
iov.iov_base = malloc(4096);
iov.iov_len = 4096;
ret = io_uring_queue_init(2, &ring, 0);
if (ret) {
printf("ring setup failed\n");
return 1;
}
sqe = io_uring_get_sqe(&ring);
if (!sqe) {
printf("get sqe failed\n");
return 1;
}
fd = get_file_fd();
if (fd < 0)
return 1;
io_uring_prep_readv(sqe, fd, &iov, 1, 0);
sqe->rw_flags = RWF_NOWAIT;
ret = io_uring_submit(&ring);
if (ret != 1) {
printf("Got submit %d, expected 1\n", ret);
goto err;
}
ret = io_uring_peek_cqe(&ring, &cqe);
if (ret) {
printf("Ring peek got %d\n", ret);
goto err;
}
if (cqe->res != -EAGAIN) {
printf("cqe error: %d\n", cqe->res);
goto err;
}
put_file_fd(fd);
return 0;
err:
put_file_fd(fd);
return 1;
}
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