Re: [Gnustep-cvs] r26723 - in /libs/base/trunk: ChangeLog Headers/Additions/GNUstepBase/config.h.in Source/GSFFIInvocation.m configure configure.ac

[David Ayers]

Hubert Chathi schrieb:
> On Sun, 29 Jun 2008 09:54:56 +0200, David Ayers <address@hidden> said:
> 
>> Hello David David Chisnall schrieb:
>>> I think calling mmap directly is the wrong solution here.  You should
>>> be using valloc() with the requested size rounded up to the nearest
>>> page size, and then use mprotect to set it as executable.  Note that
>>> most sane operating systems (and Vista) are moving to W^X, so you
>>> need to set it as writeable while creating it, then executable while
>>> using it (i.e.  call mprotect immediately before the return).
>>>
> 
>> My man page for vmalloc states:
>>        The obsolete function valloc() allocates size bytes and returns
>> a pointer to the allocated memory.  The memory address will be a
>> multiple of the page size.  It is equivalent to
>> memalign(sysconf(_SC_PAGESIZE),size).
> 
> Heh.  My man page for memalign says:
> ,----
> | The obsolete function memalign() allocates size  bytes  and  returns  a
> | pointer to the allocated memory.  The memory address will be a multiple
> | of boundary, which must be a power of two.
> `----
> and implies that posix_memalign should be used instead.  From what I can
> gather, "ptr=valloc(size)" is equivalent to
> "posix_memalign(&ptr,sysconf(_SC_PAGESIZE),size)", but don't quote me on
> that.

I'm on lenny... so one could consider that a bug in the vmalloc man
page... would you care to open a bug report?

Cheers,
David