implement POSIX asynchronous io

some features are not yet supported, and only minimal testing has been
performed. should be considered experimental at this point.

1 files changed, 16 insertions, 0 deletions

diff --git a/src/aio/aio_cancel.c b/src/aio/aio_cancel.c
new file mode 100644
index 00000000..5a753b1f
--- /dev/null
+++ b/src/aio/aio_cancel.c
@@ -0,0 +1,16 @@
+#include <aio.h>
+#include <pthread.h>
+#include <errno.h>
+
+int aio_cancel(int fd, struct aiocb *cb)
+{
+	if (!cb) {
+		/* FIXME: for correctness, we should return AIO_ALLDONE
+		 * if there are no outstanding aio operations on this
+		 * file descriptor, but that would require making aio
+		 * much slower, and seems to have little advantage since
+		 * we don't support cancellation anyway. */
+		return AIO_NOTCANCELED;
+	}
+	return cb->__err==EINPROGRESS ? AIO_NOTCANCELED : AIO_ALLDONE;
+}