[Qemu-devel] [PATCH v3 0/5] Do not set SO_REUSEADDR on Windows

[Sebastian Ottlik]

This patchset disabels all use of SO_REUSEADDR on Windows. On Windows systems
the default behaviour is equivalent to SO_REUSEADDR on other operating
systems. SO_REUSEADDR can still be set but results in undesired behaviour
instead. It may even lead to situations were system behaviour is
unspecified. More information on this can be found at:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms740621.aspx

I originally encountered this issue when accidentally launching two QEMU
instances with identical GDB ports at the same time. In which case QEMU won't
fail as one might expect.

v3 Changes:
- Fixed coding style issues.
  According to checkpatch.pl patch #4 still introduces style errors as tabs are
  used instead of space for some indentation. I keept the tabs to stay
  consistent with the sourrounding code, as tabs seem to be used consitently in
  parts (all?) of the slirp code.

- Changed patch #3 to keep SO_REUSEADDR for multicast sockets on windows and
  added an explainatory comment.

- Rebased to current master (94c2b6aff43cdfcfdfb552773a6b6b973a72ef0b).

v2 Changes:

- Introduce a function with os specific implementation instead of using #ifdef
  I named it socket_set_fast_reuse instead of the suggested qemu_set_reuseaddr
  so the name better reflects what the function actually does.

 gdbstub.c              |    6 ++----
 include/qemu/sockets.h |    1 +
 net/socket.c           |   18 ++++++++++--------
 slirp/misc.c           |    3 +--
 slirp/socket.c         |    4 +---
 slirp/tcp_subr.c       |    6 ++----
 slirp/udp.c            |    4 ++--
 util/oslib-posix.c     |   14 ++++++++++++++
 util/oslib-win32.c     |   10 ++++++++++
 util/qemu-sockets.c    |    6 +++---
 10 files changed, 46 insertions(+), 26 deletions(-)

util: add socket_set_fast_reuse function which will
gdbstub: call socket_set_fast_reuse instead of
net: call socket_set_fast_reuse instead of setting
slirp: call socket_set_fast_reuse instead of setting
util: call socket_set_fast_reuse instead of setting