Em sex., 11 de set. de 2020 às 17:44, Tom Lane <tgl@sss.pgh.pa.us> escreveu:
Ranier Vilela <ranier.vf@gmail.com> writes: > New version, with support to read Virtual File (pipe, FIFO and socket). > With assert, in case, erroneous, of trying to read a pipe, with offset.
Really, could you do a little more thinking and testing of your own, rather than expecting the rest of us to point out holes in your thinking?
Yes, I can.
* bytes_to_read == 0 is a legal case.
Ok. Strange call to read a file with zero bytes.
* "Assert(seek_offset != 0)" is an equally awful idea.
I was trying to predict the case of reading a Virtual File, with bytes_to_read == -1 and seek_offset == 0, which is bound to fail in fseeko.
In any case, 96d1f423f95d it will fail with any Virtual File.
* Removing the seek code from the negative-bytes_to_read path is just broken.
Ok.
* The only reason this code is shorter than the previous version is you took out all the comments explaining what it was doing, and failed to replace them. This is just as subtle as before, so I don't find that acceptable.
It was not my intention.
I do agree that it might be worth skipping the fseeko call in the probably-common case where seek_offset is zero. Otherwise I don't see much reason to change what's there.
Well, I think that v3 is a little better, but it’s just my opinion.
v3 try to copy directly in the final buffer, which will certainly be a little faster.
