On Mon, Aug 20, 2012 at 10:29:39AM -0600, Eric Blake wrote:
On 08/20/2012 07:49 AM, Daniel P. Berrange wrote:
From: "Daniel P. Berrange" <berrange@redhat.com>
Add a new qemuMonitorGetVersion() method to support invocation of the 'query-version' JSON monitor command. No HMP equivalent is provided, since this will only be used for QEMU >= 1.2 --- src/qemu/qemu_monitor.c | 24 ++++++++++ src/qemu/qemu_monitor.h | 7 +++ src/qemu/qemu_monitor_json.c | 78 +++++++++++++++++++++++++++++++++ src/qemu/qemu_monitor_json.h | 7 +++ tests/qemumonitorjsontest.c | 102 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 218 insertions(+)
+ if (!mon) { + virReportError(VIR_ERR_INVALID_ARG, "%s", + _("monitor must not be NULL")); + return -1;
Given this error,
+++ b/src/qemu/qemu_monitor.h @@ -574,6 +574,13 @@ int qemuMonitorGetBlockIoThrottle(qemuMonitorPtr mon,
int qemuMonitorSystemWakeup(qemuMonitorPtr mon);
+int qemuMonitorGetVersion(qemuMonitorPtr mon, + int *major, + int *minor, + int *micro, + char **package) + ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4);
why not ATTRIBUTE_NONNULL(1) as well?
We've had cases in the past where we passed a NULL 'mon' parameter and the compiler was unable to warn us: commit 31e29fe5247fd4beca437cdbc49e1b1f30884446 Author: Daniel P. Berrange <berrange@redhat.com> Date: Mon May 17 07:43:36 2010 -0400 Protect against NULL pointer flaws in monitor usage History has shown that there are frequent bugs in the QEMU driver code leading to the monitor being invoked with a NULL pointer. Although the QEMU driver code should always report an error in this case before invoking the monitor, as a safety net put in a generic check in the monitor code entry points. * src/qemu/qemu_monitor.c: Safety net to check for NULL monitor object
+ if (package) { + const char *tmp; + if (!(tmp = virJSONValueObjectGetString(data, "package"))) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("query-version reply was missing 'package' version")); + goto cleanup; + }
Why is it an error if package is non-NULL but package data was not present? Can't we just leave *package=NULL in that case, rather than erroring out? After all, when package is NULL, we don't care whether package data was present.
Well I believe this field should be mandatory in the QEMU JSON schema, so I wanted to treat it that way in libvirt too.
+ + if (qemuMonitorTestAddItem(test, "query-version", + "{ " + " \"return\":{ " + " \"qemu\":{ " + " \"major\":0, " + " \"minor\":11, " + " \"micro\":6 " + " }," + " \"package\":\"2.283.el6\"" + " }" + "}") < 0)
Shouldn't we test typical values in use by actual qemu? For example, with RHEL, I see something like "package":"(qemu-kvm-0.12.1.2)".
Oh it was supposed to match, but I guess I messed up
Overall, I like the idea. But do we have any code that uses the new monitor command, besides the testsuite?
Not yet, I was just sending this code out for early review. I'm working on a series to stop parsing -help and this is a pre-requisite for it. Likewise the other commands Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|