Re: [libvirt] [PATCH] qemu: Report cmdline output if VM dies early
On 04/30/2010 09:44 AM, Cole Robinson wrote:
qemuReadLogOutput early VM death detection is racy and won't
always work.
Startup then errors when connecting to the VM monitor. This won't report
the emulator cmdline output which is typically the most useful diagnostic.
Check if the VM has died at the very end of the monitor connection step,
and if so, report the cmdline output.
+static void
+qemuReadLogFD(int logfd, char *buf, int maxlen, int off)
+{
+ int ret;
+ char *tmpbuf = buf+off;
Isn't the style to separate operators by space? 'buf + off'
+
+ ret = saferead(logfd, tmpbuf, maxlen-off-1);
Likewise, 'maxlen - off - 1'.
+ if (ret < 0) {
+ ret = 0;
+ }
+
+ *(tmpbuf+ret) = '\0';
Stylistically, I like 'tmpbuf[ret]' better than '*(tmpbuf+ret)'.
+}
+
static int
qemudWaitForMonitor(struct qemud_driver* driver,
virDomainObjPtr vm, off_t pos)
{
- char buf[4096]; /* Plenty of space to get startup greeting */
+ char buf[4096] = "\0"; /* Plenty of space to get startup greeting */
"" is sufficient; you don't have to use "\0" to zero-initialize a
statically sized char[].
But overall, the patch looks sane; I didn't see any logic errors.
ACK with the style nits addressed.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org
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