On Fri, 29 Nov 2024 12:43:28 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org>
wrote:
>> src/java.base/share/classes/jdk/internal/foreign/StringSupport.java line 187:
>>
>>> 185: // Prevent over scanning as we step by 2
>>> 186: final long endScan = toOffset & ~1; // The last bit is zero
>>> 187: for (; offset < endScan; offset += Short.BYTES) {
>>
>> Question: do we care about finding unaligned sequences of two consecutive
>> zero bytes? Because I don't think this method can detect those. E.g. if the
>> first zero byte in a terminator sequence starts at an odd offset I don't
>> think we can recognize the terminator.
>>
>> This is a bit of a weird side-effect, because now this method no longer
>> behaves like a plain byte loop where we look for two consecutive bytes. But,
>> I suppose, in a way it also makes sense: if I want to read a C string whose
>> characters are 2-bytes each, then I definitively need to scan the segment
>> (at given offset) two bytes at a time. A terminator at an "odd offset" from
>> the start of the scan is not good. I believe the javadoc is a bit "light" on
>> how this terminator is actually found :-)
>
> Even the fact that the last byte is ignored (if length is odd), or that up to
> 3 bytes might be ignored in the `strlenInt` might not be obvious. Maybe we
> should file a followup PR for improving the javadoc?
https://bugs.openjdk.org/browse/JDK-8345292
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/22451#discussion_r1865596703
