parse: Truncate GNU LongName/LongLink content at the first NUL byte#28
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The GNU tar format specifies that LongName and LongLink content is a NUL-terminated C string. The previous code only stripped a single trailing NUL, which could cause confusion for callers because in practice filenames can't have embedded NUL bytes. GNU tar, Python tarfile, and Go archive/tar all truncate at the first NUL. Assisted-by: OpenCode (Claude Sonnet 4.6) Signed-off-by: Colin Walters <walters@verbum.org>
…harness tar-core now truncates the resolved path/link-target at the first NUL byte for GNU LongName/LongLink headers, matching GNU tar's C-string convention (commit 92ea76d). tar-rs does not perform this truncation, so the cargo-fuzz differential harness was failing on any archive where the GNU long-name/link content contains an embedded NUL. The fix is in the testutil's parse_tar_rs function: normalize path and link_target by truncating at the first NUL before comparison. This is the same logic tar-core applies, so both sides now represent the same semantically correct value. The differential.rs module doc is updated to document this as an allowlisted behavioral difference. Assisted-by: OpenCode (Claude Sonnet 4.6) Signed-off-by: Colin Walters <walters@verbum.org>
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The GNU tar format specifies that LongName and LongLink content is a NUL-terminated C string. The previous code only stripped a single trailing NUL, which could cause confusion for callers because in practice filenames can't have embedded NUL bytes.
GNU tar, Python tarfile, and Go archive/tar all truncate at the first NUL.
Assisted-by: OpenCode (Claude Sonnet 4.6)