Re: [Libguestfs] [nbdkit PATCH 0/3] Fix %m usage on BSD
On Thu, Nov 29, 2018 at 11:21:27AM -0600, Eric Blake wrote:
Our use of "%m" in various error messages is testament to
the
project's initial life on Linux - but other than Cygwin, I know
of no other platforms supporting that glibc extension.
We COULD audit the code and manually turn "%m" into
"%s"/strerror(errno), but that's a lot of churn. Instead, let's
fix the few outliers that can't be easily wrapped, then wrap
the remainder.
While I was able to test this on Linux (both that no wrapper is
used by default, and that faking that %m fails causes the wrapper
to do the right thing), I haven't actually tried it on a BSD box,
hence I'll wait for review before pushing.
I tested these on FreeBSD 11.2:
checking whether the printf family supports %m... no
and then:
$ ./nbdkit file /dev/pci -f -v
(where /dev/pci is unreadable by non-root). When accessing this
device I see errors like:
nbdkit: debug: accepted connection
nbdkit: debug: file: open readonly=0
nbdkit: error: open: /dev/pci: Permission denied
which I believe are evidence that the %m formatter is being expanded
correctly in plugins/file/file.c.
Also without your patches I see:
nbdkit: error: open: /dev/pci: m
I checked the patches themselves and they look fine too so:
ACK series
Thanks,
Rich.
--
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