[libvirt] ESX driver connection private data fix

Hi, first time poster, my apologies if this is not the correct avenue. Since release 0.9.11, I've been getting a segfault in virsh attempting to access an ESXi 4.1 host. GDB reports it as such: ** Program received signal SIGSEGV, Segmentation fault. esxConnectToHost (vCenterIpAddress=0x7fffffffd640, auth=0x7ffff7fef5e0, conn=0x675780) at esx/esx_driver.c:726 726 if (virAsprintf(&url, "%s://%s:%d/sdk", priv->parsedUri->transport, (gdb) bt #0 esxConnectToHost (vCenterIpAddress=0x7fffffffd650, auth=0x7ffff7fef5e0, conn=0x675780) at esx/esx_driver.c:726 #1 esxOpen (conn=0x675780, auth=0x7ffff7fef5e0, flags=<optimized out>) at esx/esx_driver.c:1052 #2 0x00007ffff7bc243a in do_open (name=0x6745a0 "esx://XXX/?no_verify=1", auth=0x7ffff7fef5e0, flags=0) at libvirt.c:1227 #3 0x00007ffff7bc48e6 in virConnectOpenAuth (name=0x6745a0 "esx://XXX/?no_verify=1", auth=0x7ffff7fef5e0, flags=0) at libvirt.c:1456 #4 0x000000000040ac8f in vshInit (ctl=0x7fffffffe210) at virsh.c:19288 #5 main (argc=<optimized out>, argv=0x7fffffffe508) at virsh.c:20046 ** Digging through the code a bit, I found that in esxOpen(), the "conn" virConnectPtr var is passed to esxConnectToHost() with a nil pointer to a virConnect "privateData" pointer. The hypervisor transport type (among other things in "parsedUri") is stored here, and a crash/segfault occurs in esxConnectToHost() when attempting to access the transport for virAsprintf() at line 726 of src/esx/esx_driver.c. This patch just makes sure we're pointing to something before attempting to use anything in the struct. Cleanly applied to git from this afternoon, built and successfully tested on a Fedora 16/x86_64 VM accessing an ESXi 4.1 node. --   ryan woodsmall     rwoodsmall(a)gmail.com