Re: No error checking when reading from file using zstd in pg_dump

Daniel Gustafsson <daniel(at)yesql(dot)se> writes:
> I spent a little bit of time reading over all the implementations and cross
> referencing the API for conformity, and came up with the attached. The 0001
> patch is the one from upstream, and each subsequent commit is fixing one
> function for all the implementations. Before pushing it should all be squashed
> into a single commit IMHO.

Thanks for tackling this!

I looked over this patchset briefly, and found a couple of nits:

v5-0002, in compress_io.h:

+ * Returns true on success and throws error for all error conditions.

It doesn't return true anymore. Should be more like

+ * Returns nothing. Exits via pg_fatal for all error conditions.

In LZ4Stream_write: you dropped the bit about

- errno = (errno) ? errno : ENOSPC;

but I think that's still necessary: we must assume ENOSPC if fwrite
doesn't set errno. Other fwrite callers (write_none, Zstd_write) need
this too. v5-0004 has an instance too, in Zstd_close. I did not check
to see if other fwrite calls are OK, but it'd be good to verify
that they all follow the pattern of presetting errno to 0 and then
replacing that with ENOSPC.

regards, tom lane