Relax assertions for zero-length accesses (for v0.2.2) #108
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Relax the assertions from write_to and read_from to allow equality between offset and count, which no longer leads to panics when zero-length accesses happen. This is preferred versus adding an explicit check for count or len == 0 somewhere, because we don't end up with an additional branch on the regular path. Also tweaked the try_access logic a bit, to return Ok(0) when total == 0 but we found a valid region associated with the current address (which indicates a zero-length access). Signed-off-by: Alexandru Agache <aagch@amazon.com>
Updated changelog and Cargo.toml version. Dropped coverage by 0.1, because the CI complains even though the previous commit adds more test operations than new code. Signed-off-by: Alexandru Agache <aagch@amazon.com>
andreeaflorescu
approved these changes
Aug 3, 2020
rbradford
approved these changes
Aug 5, 2020
jiangliu
approved these changes
Aug 5, 2020
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Related to #106
Relax the assertions from
write_toandread_fromto allow equality betweenoffsetandcount, which no longer leads to panics when zero-length accesses happen. This is preferred versus adding an explicit check forcountorlen == 0somewhere, because we don't end up with an additional branch on the regular path. Also tweaked thetry_accesslogic a bit, to returnOk(0)whentotal == 0but we found a valid region associated with the current address (which indicates a zero-length access).