Re: [Qemu-devel] [PATCH v2] qemu-ga: guest-shutdown: use only async-signal-safe functions

[Eric Blake <eblake@redhat.com>]

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On 05/14/2012 12:25 PM, Luiz Capitulino wrote:
> POSIX mandates[1] that a child process of a multi-thread program uses
> only async-signal-safe functions before exec(). We consider qemu-ga
> to be multi-thread, because it uses glib.
> 
> However, qmp_guest_shutdown() uses functions that are not
> async-signal-safe. Fix it the following way:
> 
> - fclose() -> reopen_fd_to_null()
> - execl() -> execle()
> - exit() -> _exit()
> - drop slog() usage (which is not safe)
> 
>   [1] http://pubs.opengroup.org/onlinepubs/009695399/functions/fork.html
> 
> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
> ---
> 
> o v2
> 
> - fix doc typo
> - drop 'ret' and use EXIT_FAILURE instead

Not addressed was the 'environ' declaration issue, but I'm okay if you
save it for another day when we actually get a compile failure for using
an undeclared variable (since what you have _does_ work on glibc).

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake   eblake@redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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