examples/io_uring-test: don't error on shorter files

The example currently assumes the file is at least 4*4096 bytes,
and errors when we get 0 reads on EOF. Fix this up.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 21 insertions, 2 deletions

diff --git a/examples/io_uring-test.c b/examples/io_uring-test.c
index 1da8407..1a68536 100644
--- a/examples/io_uring-test.c
+++ b/examples/io_uring-test.c
@@ -9,6 +9,8 @@
 #include <fcntl.h>
 #include <string.h>
 #include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <unistd.h>
 #include "liburing.h"
 
@@ -21,6 +23,8 @@ int main(int argc, char *argv[])
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	struct iovec *iovecs;
+	struct stat sb;
+	ssize_t fsize;
 	off_t offset;
 	void *buf;
 
@@ -41,12 +45,19 @@ int main(int argc, char *argv[])
 		return 1;
 	}
 
+	if (fstat(fd, &sb) < 0) {
+		perror("fstat");
+		return 1;
+	}
+
+	fsize = 0;
 	iovecs = calloc(QD, sizeof(struct iovec));
 	for (i = 0; i < QD; i++) {
 		if (posix_memalign(&buf, 4096, 4096))
 			return 1;
 		iovecs[i].iov_base = buf;
 		iovecs[i].iov_len = 4096;
+		fsize += 4096;
 	}
 
 	offset = 0;
@@ -58,16 +69,22 @@ int main(int argc, char *argv[])
 		io_uring_prep_readv(sqe, fd, &iovecs[i], 1, offset);
 		offset += iovecs[i].iov_len;
 		i++;
+		if (offset > sb.st_size)
+			break;
 	} while (1);
 
 	ret = io_uring_submit(&ring);
 	if (ret < 0) {
 		fprintf(stderr, "io_uring_submit: %s\n", strerror(-ret));
 		return 1;
+	} else if (ret != i) {
+		fprintf(stderr, "io_uring_submit submitted less %d\n", ret);
+		return 1;
 	}
 
 	done = 0;
 	pending = ret;
+	fsize = 0;
 	for (i = 0; i < pending; i++) {
 		ret = io_uring_wait_cqe(&ring, &cqe);
 		if (ret < 0) {
@@ -77,16 +94,18 @@ int main(int argc, char *argv[])
 
 		done++;
 		ret = 0;
-		if (cqe->res != 4096) {
+		if (cqe->res != 4096 && cqe->res + fsize != sb.st_size) {
 			fprintf(stderr, "ret=%d, wanted 4096\n", cqe->res);
 			ret = 1;
 		}
+		fsize += cqe->res;
 		io_uring_cqe_seen(&ring, cqe);
 		if (ret)
 			break;
 	}
 
-	printf("Submitted=%d, completed=%d\n", pending, done);
+	printf("Submitted=%d, completed=%d, bytes=%lu\n", pending, done,
+						(unsigned long) fsize);
 	close(fd);
 	io_uring_queue_exit(&ring);
 	return 0;