[COMPRESS-571] 7z random access fails on shuffled entry list

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.20
• Fix Version/s: 1.21
• Assignee: Peter Lee
• Reporter: Robin Schimpf
• Created: 16/Mar/21 19:33
• Updated: 20/Mar/23 13:17
• Resolved: 20/Mar/23 13:17

Description

I noticed a problem on a 7z file and could reproduce the error if the InputStream is retrieved after shuffling the entries.

This test fails with a checksum verification error

@Test
public void retrieveInputStreamForShuffledEntries() throws IOException {
    try (final SevenZFile sevenZFile = new SevenZFile(getFile("COMPRESS-256.7z"))) {
        List<SevenZArchiveEntry> entries = (List<SevenZArchiveEntry>) sevenZFile.getEntries();
        Collections.shuffle(entries);
        for (final SevenZArchiveEntry entry : entries) {
            IOUtils.toByteArray(sevenZFile.getInputStream(entry));
        }
    }
}

This is the exception

java.io.IOException: Checksum verification failed
	at org.apache.commons.compress.utils.ChecksumVerifyingInputStream.read(ChecksumVerifyingInputStream.java:94)
	at org.apache.commons.compress.utils.ChecksumVerifyingInputStream.read(ChecksumVerifyingInputStream.java:74)
	at org.apache.commons.compress.utils.IOUtils.copy(IOUtils.java:87)
	at org.apache.commons.compress.utils.IOUtils.copy(IOUtils.java:62)
	at org.apache.commons.compress.utils.IOUtils.toByteArray(IOUtils.java:247)
	at org.apache.commons.compress.archivers.sevenz.SevenZFileTest.retrieveInputStreamForShuffledEntries(SevenZFileTest.java:616)

This also fails on the current master with the same error