RFR: 8280881: (fs) UnixNativeDispatcher.close0 may throw UnixException

[Jaikiran Pai]

On Mon, 14 Feb 2022 21:21:14 GMT, Brian Burkhalter <bpb at openjdk.org> wrote:

> Re-specify `sun.nio.fs.UnixNativeDispatcher.close0()` to throw `sun.nio.fs.UnixException` and modify callers either to ignore it or to rethrow it as an `IOException`, as appropriate.

src/java.base/unix/classes/sun/nio/fs/UnixUserDefinedFileAttributeView.java line 139:

> 137:                 close(fd);
> 138:             } catch (UnixException y) {
> 139:                 y.rethrowAsIOException(file);

Hello Brian,
A few lines above this code in the finally block, there's a catch block which catches the `UnixException` and rethrows it as a `FileSystemException`. With the change being done in this finally block, this finally block now potentially can throw an `IOException` from a failed call to `close()` and thus the original `FileSystemException` can get lost. Do you think it would be better to keep track any potential `FileSystemException` from the previous catch block and add this `IOException` from this `close()` call as a suppressed exception to that `FileSystemException` and rethrow that original exception? Loosely, something like:


IOException failure = null;
try {
	....

} catch (UnixException x) {
	failure = new FileSystemException(file.getPathForExceptionMessage(),
	    null, "Unable to get list of extended attributes: " +
	    x.getMessage());
} finally {
    try {
	    close(fd);
	} catch (UnixException y) {
		if (failure == null) {
			// throw the exception that happened during close
			y.rethrowAsIOException(file);
		} else {
			// add the failure to close as a suppressed exception to
			// the previously caught failure
			failure.addSuppressed(y.asIOException(file));
		}
	}
	// throw any previously caught failure
	if (failure != null) {
		throw failure;
	}
}


This applies to few others places that have changed in this PR.

-------------

PR: https://git.openjdk.java.net/jdk/pull/7467