tree e1e3d1ccbc0cecc0d4a0c071a7d18b8463687d4f
parent 2b5d6ba0341588e4bbd53d6055118e5472657b49
author David Benjamin <davidben@google.com> 1689368653 -0400
committer Boringssl LUCI CQ <boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com> 1689791113 +0000

Tidy up error handling for sockets vs fds

On Windows, sockets and fds are different, so we need to be a little
carefully. The fd functions (which are really a userspace construct
inside the libc) report errors by writing to errno:
https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/read?view=msvc-170

While the socket functions (which are really thin wrappers over Windows
HANDLEs) use WSAGetLastError:
https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-recv
https://learn.microsoft.com/en-us/windows/win32/winsock/error-codes-errno-h-errno-and-wsagetlasterror-2

Moreover, the error values are different, so we shouldn't mix them
together:
https://learn.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2
https://learn.microsoft.com/en-us/cpp/c-runtime-library/errno-constants?view=msvc-170

Finally, by borrowing OpenSSL's distinct OPENSSL_NO_SOCK and
OPENSSL_NO_POSIX_IO options, we arguably should account for all
combinations of one or the other being missing. (Ugh.) To account for
that, I've moved bio_fd_should_retry into its own file that isn't
conditioned on anything. It only depends on <errno.h>, which is part of
the C standard library, and used elsewhere already.

Change-Id: I0519d7d68c32062e1220ffca0ab57a9cac9f7e5f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/61729
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>