openinx commented on code in PR #4608: URL: https://github.com/apache/iceberg/pull/4608#discussion_r857078910
########## core/src/main/java/org/apache/iceberg/io/IOUtil.java: ########## @@ -0,0 +1,67 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.iceberg.io; + +import java.io.IOException; +import java.io.InputStream; + +public class IOUtil { + // not meant to be instantiated + private IOUtil() { + } + + /** + * Reads into a buffer from a stream, making multiple read calls if necessary. + * + * @param stream an InputStream to read from + * @param bytes a buffer to write into + * @param offset starting offset in the buffer for the data + * @param length length of bytes to copy from the input stream to the buffer + * @throws IOException if there is an error while reading + */ + @SuppressWarnings("checkstyle:InnerAssignment") + public static void readFully(InputStream stream, byte[] bytes, int offset, int length) throws IOException { + if (readToEnd(stream, bytes, offset, length) != length) { + throw new IOException("End of stream reached before completing read"); + } + } + + /** + * Reads into a buffer from a stream, making multiple read calls if necessary + * returning the number of bytes read until end of stream. + * + * @param stream an InputStream to read from + * @param bytes a buffer to write into + * @param offset starting offset in the buffer for the data + * @param length length of bytes to copy from the input stream to the buffer + * @throws IOException if there is an error while reading + */ + @SuppressWarnings("checkstyle:InnerAssignment") + public static int readToEnd(InputStream stream, byte[] bytes, int offset, int length) throws IOException { + int pos = offset; + int bytesRead = 0; + + while ((length - bytesRead) > 0 && (bytesRead = stream.read(bytes, pos, length - bytesRead)) > 0) { + pos += bytesRead; + } Review Comment: Is this loop correct ? If we have a stream with 1000 bytes, and the offset = 0, length = 100, assume we will read 10 bytes for each `stream.read(...)`. Then: 1. For the first read, everything works fine, and the `pos` advanced to 10; 2. For the second read, it will try to read by the `stream.read(bytes, 10, 100-10) `. Then the `pos` advanced to 20; 3. For the third read, it will try to read by the `stream.read(bytes, 20, 100-10)`. In fact, we only need to read the remaining 80 bytes but we are passing the `100-10=90` bytes ? That should be a problem.... -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
