If a socket is closed it remains in TIME_WAIT state for some time. On operating
systems using BSD sockets the endpoint of the socket may not be reused while in
this state unless SO_REUSEADDR was set on the socket. On windows on the other
hand the default behaviour is to allow reuse (i.e. identical to SO_REUSEADDR on
other operating systems) and setting SO_REUSEADDR on a socket allows it to be
bound to a endpoint even if the endpoint is already used by another socket
independently of the other sockets state. This can even result in undefined
behaviour.
Many sockets used by QEMU should not block the use of their endpoint after being
closed while they are still in TIME_WAIT state. Currently QEMU sets SO_REUSEADDR
for such sockets, which can lead to problems on Windows. This patch introduces
the function socket_set_fast_reuse that should be used instead of setting
SO_REUSEADDR when fast socket reuse is desired and behaves correctly on all
operating systems.
As a failure of this function can only be caused by bad QEMU internal errors, an
assertion handles these situations. The return value is still passed on, to
minimize changes in client code and prevent unused variable warnings if NDEBUG
is defined.
Signed-off-by: Sebastian Ottlik <ottlik@fzi.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
We abort() on memory allocation failure. abort() is appropriate for
programming errors. Maybe most memory allocation failures are
programming errors, maybe not. But guest memory allocation failure
isn't, and aborting when the user asks for more memory than we can
provide is not nice. exit(1) instead, and do it in just one place, so
the error message is consistent.
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1375276272-15988-8-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>
This function returns ${prefix}/var/RELATIVE_PATHNAME on POSIX-y systems,
and <CSIDL_COMMON_APPDATA>/RELATIVE_PATHNAME on Win32.
http://msdn.microsoft.com/en-us/library/bb762494.aspx
[...] This folder is used for application data that is not user
specific. For example, an application can store a spell-check
dictionary, a database of clip art, or a log file in the
CSIDL_COMMON_APPDATA folder. [...]
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
We switched from qemu_memalign to mmap() but then we don't modify
qemu_vfree() to do a munmap() over free(). Which we cannot do
because qemu_vfree() frees memory allocated by qemu_{mem,block}align.
Introduce a new function that does the munmap(), luckily the size is
available in the RAMBlock.
Reported-by: Amos Kong <akong@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Message-id: 1368454796-14989-3-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is preparatory to the introduction of a separate freeing API.
Reported-by: Amos Kong <akong@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Message-id: 1368454796-14989-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The fcntl(fd, F_SETFL, O_NONBLOCK) flag is not specific to sockets.
Rename to qemu_set_nonblock() just like qemu_set_cloexec().
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
On POSIX, qemu_vfree() accepts NULL, because it's merely wrapper
around free(). As far as I can tell, the Windows implementation
doesn't. Breeds bugs that bite only under Windows.
Make the Windows implementation behave like the POSIX implementation.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
