errno-ntstatus conversion

[Mike Kaplinskiy]

There are many places where we need to do a conversion between the
unix errno and the windows ntstatus (and then sometimes to dos
errors). Here are some that I found:

http://source.winehq.org/source/server/file.c#L582
http://source.winehq.org/source/server/sock.c#L702
http://source.winehq.org/source/dlls/wininet/netconnection.c#L512
http://source.winehq.org/source/dlls/winhttp/net.c#L153
http://source.winehq.org/source/dlls/ntdll/file.c#L312

Would it be a good idea to perhaps create an include file for both the
server and the dlls to convert unix error codes to status/winsock
error codes? The reason for 2 functions is winsock error codes do not
actually map to any status code, they seem to be there to make porting
easier (ie STATUS_CONNECTION_RESET maps to ERROR_CONNECTION_RESET).
Does this seem reasonable, or should we just keep duplicating the
conversion code everywhere? I have not checked whether there are
places that have different statuses for the same unix error, but
presumably we can pick a reasonable default and just have special
cases within the module.

This is coming from some conversion within the server. The server
should not return wsa-based error codes in its error events list, and
just use wsa conversion when sending window messages.

Mike.