Re: [PATCH]: Thread safe stdio with cygwin

[Thomas Pfaff <tpfaff at gmx dot net>]

Jeff,

memset makes only sure that _lock does not contain random data before 
__lock_init_recursive. __lock_init_recursive is called later when the 
file is really opened.

__sbprintf is a special case because it generates a fake FILE pointer 
and its associated buf on the stack, therefore there is no need to lock 
it fo thread safety.

Thomas

Jeff Johnston wrote:
> Thomas,
>
>  You should be using __lock_init_recursive to initialize the locks 
> rather than zeroing them out.
> The code in __sbprintf should probably be closing the lock after the 
> call to VFPRINTF as well.
>
> -- Jeff J.
>
> Thomas Pfaff wrote:
>
> > This patch adds support for thread safe stdio for Cygwin.
> >
> > Cygwin uses dynamic mutexes for locking, therefore it is
> > necessary to:
> >
> > 1. Initialize FILE pointers _lock properly.
> > 2. Destroy the lock when it is no longer needed.
> >
> > Regards,
> >
> > Thomas
> >
> > 2004-01-12  Thomas Pfaff  <tpfaff@gmx.net>
> >
> >     * libc/stdio/fclose.c: Include sys/lock.h.
> >     (fclose): Destroy lock when file is closed.
> >     * libc/stdio/findfp.c (__sfp): Initialize file pointers _lock
> >     member.
> >     * libc/stdio/freopen.c: Include sys/lock.h.
> >     (_freopen_r): Destroy lock when file is closed.
> >     * libc/stdio/vfprintf.c (__sbprintf): Initialize file pointers
> >     _lock member.
> >
> >