Re: [Monotone-devel] hang on Win32/MinGW with sync file:

[Stephen Leake]

Matthew Gregan <address@hidden> writes:

>> Note that dumb_socketpair is _not_ actually cross-platform; it has the
>> same #ifdef WIN32 style that netxx_pipe.cc currently has, and the WIN32
>> version has an extra parameter that is important. Apparently 'socketpair'
>> is implemented on some/most "unix" platforms, but not on Win32?
>
> Right, that code is an implementation of socketpair() for Windows because it
> is not provided by the Windows socket API.  Cross platform refers to the
> rest of the code--all platforms can use socketpair() and almost all of the
> rest of the code can be shared between platforms (except for process
> creation, but we probably already have sufficient wrappers for these in the
> $platform/ directories already).

Currently, all code outside netxx_pipe.cc uses netxx_pipe.cc. So I
don't see what we are gaining by replacing Unix pipes by TCP sockets.

>> I don't think there's any reason to change the non-WIN32 parts of
>> netxx_pipe.cc. Although we should split netxx_pipe.cc into
>> win32/netxx_pipe.cc, unix/netxx_pipe.cc.
>
> We try to keep as much code as possible cross platform. 

I'm not clear what you mean by "cross platform".

To me, that means "not needing '#ifdef OS'". Clearly, netxx_pipe.cc
needs '#ifdef OS'.

> I'd prefer to keep the code shared in the top level netxx_pipe.cc

netxx_pipe.cc is mostly either WIN32 or Unix; almost none of it is shared.

> and just have any OS-specific wrappers pushed down into the
> $platform/ directories. In this case, that would be the
> dumb_socketpair code and possibly some extension to our existing
> process creation code.
>
>> So it would be cleaner to copy the dumb_socketpair implementation idea,
>> directly in netxx_pipe.cc, rather than using dumb_socketpair as is. That
>> could work around the license issue as well.
>
> I'd prefer to ask Nathan about the license and then include the file
> directly. 
>
> The Win32 specific code can go in win32/socketpair.c. 

The Win32 specific code implementing sockets is less complex than the
current WIN32 specific code in netxx_pipe.cc. So the minimal change to
the current system is to just replace that.

> The unix/ implementation can just call the real socketpair()
> directly like the !WIN32 case in socketpair.c does.

Why should we change the unix part of netxx_pipe.cc? It's not broken;
let's not "fix" it.

-- 
-- Stephe