Re: [libvirt] PATCH: Fix infinite loop when QEMU quits at startup

The recent refactoring of the QEMU startup process now reads the monitor TTY from the logfile. Unfortunately in this refactoring we lost the check for the 'ret == 0' scenario in the read() return value. So if QEMU quits at startup, eg due to missing disk image, we loop forever on read() == 0 because we hit end-of-file and QEMU has quit. This patch adds back handling for this scenario, and takes care to propagate the contents of the log to the user as an error message # start demo libvir: QEMU error : internal error unable to start guest: qemu: could not open disk image /home/berrange/Fedora-9-i686-Live.iso error: Failed to start domain demo In addition, there were a couple of other bugs - a memory leak where we set the 'monitorpath' variable, even though we'd just set it moments before. - a missing check for whether the driver VNC password was present when initializing passwords at VM startupo - missing initialization of the monitor_watch field, and missing checking for whether the watch was set before removing it. - a gratuitous LOG_INFO when shutting down any VM, which could just be LOG_DEBUG.