bpo-27584: New addition of vSockets to the python socket module (#2489)

* bpo-27584: New addition of vSockets to the python socket module

Support for AF_VSOCK on Linux only

* bpo-27584: Fixes for V2

Fixed syntax and naming problems.
Fixed #ifdef AF_VSOCK checking
Restored original aclocal.m4

* bpo-27584: Fixes for V3

Added checking for fcntl and thread modules.

* bpo-27584: Fixes for V4

Fixed white space error

* bpo-27584: Fixes for V5

Added back comma in (CID, port).

* bpo-27584: Fixes for V6

Added news file.
socket.rst now reflects first Linux introduction of AF_VSOCK.
Fixed get_cid in test_socket.py.
Replaced PyLong_FromLong with PyLong_FromUnsignedLong in socketmodule.c
Got rid of extra AF_VSOCK #define.
Added sockaddr_vm to sock_addr.

* bpo-27584: Fixes for V7

Minor cleanup.

* bpo-27584: Fixes for V8

Put back #undef AF_VSOCK as it is  necessary when vm_sockets.h is not installed.

1 files changed, 18 insertions, 0 deletions

diff --git a/configure b/configure
index 3880421dba..75d64324e6 100755
--- a/configure
+++ b/configure
@@ -8088,6 +8088,24 @@ fi
 done
 
 
+for ac_header in linux/vm_sockets.h
+do :
+  ac_fn_c_check_header_compile "$LINENO" "linux/vm_sockets.h" "ac_cv_header_linux_vm_sockets_h" "
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+
+"
+if test "x$ac_cv_header_linux_vm_sockets_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LINUX_VM_SOCKETS_H 1
+_ACEOF
+
+fi
+
+done
+
+
 # On Linux, can.h and can/raw.h require sys/socket.h
 for ac_header in linux/can.h linux/can/raw.h linux/can/bcm.h
 do :