On 09/28/2012 07:08 AM, Daniel P. Berrange wrote:
From: "Daniel P. Berrange" <berrange@redhat.com>
Add support for logging to the systemd journal, using its simple client library. The benefit over syslog is that it accepts structured log data, so the journald can store individual items like code file/line/func separately from the string message. Tools which require structured log data can then query the journal to extract exactly what they desire without resorting to string parsing
While systemd provides a simple client library for logging, it is more convenient for libvirt to directly write its own client code. This lets us build up the iovec's on the stack, avoiding the need to alloc memory when writing log messages.
+ + if (strchr(rawstr, '\n')) { + uint64_t nstr; + /* If 'str' containes a newline, then we must + * encode the string length, since we can't + * rely on the newline for the field separator + */ + IOVEC_SET_STRING(iov[niov++], "MESSAGE\n"); + nstr = htole64(strlen(rawstr));
+ if ((buffd = mkostemp(path, O_CLOEXEC|O_RDWR)) < 0) + return;
It turns out that RHEL 5 glibc is too old to have either htole64 or mkostemp. Gnulib has mkostemp, and I could add htole64 to gnulib easily enough. But when you realize that this will only ever work on systems with systemd, and that RHEL 5 lacks systemd, the easier fix is to just disable compilation of systemd logging on RHEL 5. Patch coming up. -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org