RE: [PATCH v2 1/7] common: add scoped_fd

["Metzger, Markus T" <markus.t.metzger@intel.com>]

Hello Yao,

Looks like they added mkstemp() in 2015 after a few complaints:
https://sourceforge.net/u/jeisele123/mingw-w64/ci/f713f639f6f017371c5176f4deab07d1a92473b4/

How about checking for mkstemp and, if not available, falling back to tmpnam.
Something like this:

#ifndef HAVE_MKSTEMP

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>

/* Define a racy version of mkstemp based on tmpnam for systems that do not
   support mkstemp.  */
static int
mkstemp (char *name)
{
  if (strlen (name) < L_tmpnam)
    return -1;

  name = tmpnam (name);
  if (name == nullptr)
    return -1;

  return open (name);
}

#endif /* HAVE_MKSTEMP */


regards,
markus.

> -----Original Message-----
> From: Metzger, Markus T
> Sent: 14 February 2018 18:26
> To: Yao Qi <qiyaoltc@gmail.com>
> Cc: GDB Patches <gdb-patches@sourceware.org>
> Subject: RE: [PATCH v2 1/7] common: add scoped_fd
> 
> Hello Yao,
> 
> > > Could you try setting, say, _POSIX_C_SOURCE or try using mkostemp()
> > > instead
> > of mkstemp()?
> > >
> >
> > None of them works with my i686-w64-mingw32-g++ 4.8.2.  :(
> 
> Thanks for trying.  I will look into this.
> 
> Regards,
> Markus.
> 
> > -----Original Message-----
> > From: Yao Qi [mailto:qiyaoltc@gmail.com]
> > Sent: 14 February 2018 16:23
> > To: Metzger, Markus T <markus.t.metzger@intel.com>
> > Cc: GDB Patches <gdb-patches@sourceware.org>
> > Subject: Re: [PATCH v2 1/7] common: add scoped_fd
> >
> > On Tue, Feb 13, 2018 at 5:28 PM, Metzger, Markus T
> > <markus.t.metzger@intel.com> wrote:
> > >
> > > This is supposed to be a glibc function.  But it is guarded by some
> > > feature
> > macros.
> > > Quote from mkstemp(3): "
> > >
> > >        mkstemp():
> > >            _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500 ||
> > _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
> > >            || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200112L
> > >
> > >        mkostemp(): _GNU_SOURCE
> > >        mkstemps(): _BSD_SOURCE || _SVID_SOURCE
> > >        mkostemps(): _GNU_SOURCE
> > > "
> > >
> > > Maybe the newer compiler is setting some macros automatically that
> > > the older
> > compiler doesn't set.
> > > Could you try setting, say, _POSIX_C_SOURCE or try using mkostemp()
> > > instead
> > of mkstemp()?
> > >
> >
> > None of them works with my i686-w64-mingw32-g++ 4.8.2.  :(
> >
> > > If that doesn't help, I'll try to find a Ubuntu 14.04 to reproduce the issue.
> > >
> >
> > --
> > Yao (齐尧)
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