[libvirt] [PATCH] [RESEND] qemu: record timestamp in qemu domain log

[Daniel P. Berrange]

On Tue, Nov 16, 2010 at 04:11:40PM +0800, Osier Yang wrote:
> Currently only support domain start and shutdown, for domain start,
> record timestamp before the qemu command line, and for domain shutdown,
> just say it's shutting down with timestamp.
> 
> * src/qemu/qemu_driver.c
> ---
>  src/qemu/qemu_driver.c |   47 +++++++++++++++++++++++++++++++++++++++++++++--
>  1 files changed, 45 insertions(+), 2 deletions(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index fd61864..423befb 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -3877,6 +3877,7 @@ static int qemudStartVMDaemon(virConnectPtr conn,
>      char ebuf[1024];
>      char *pidfile = NULL;
>      int logfile = -1;
> +    char *timestamp;
>      qemuDomainObjPrivatePtr priv = vm->privateData;
> 
>      struct qemudHookData hookData;
> @@ -4084,7 +4085,17 @@ static int qemudStartVMDaemon(virConnectPtr conn,
>              goto cleanup;
>      }
> 
> +    if ((timestamp = virTimestamp()) == NULL) {
> +        virReportOOMError();
> +        goto cleanup;
> +    } else if (safewrite(logfile, timestamp, strlen(timestamp)) < 0) {
> +        VIR_WARN("Unable to write timestamp to logfile: %s",
> +                 virStrerror(errno, ebuf, sizeof ebuf));
> +        VIR_FREE(timestamp);
> +    }

Surely we want the VIR_FREE(timestamp) outside the 'else if'. This
code is only freeing the memory upon write failure.

>  static void qemudShutdownVMDaemon(struct qemud_driver *driver,
>                                    virDomainObjPtr vm,
>                                    int migrated) {
> @@ -4243,10 +4253,44 @@ static void qemudShutdownVMDaemon(struct qemud_driver *driver,
>      virErrorPtr orig_err;
>      virDomainDefPtr def;
>      int i;
> +    int logfile = -1;
> +    char *timestamp;
> +    char ebuf[1024];
> 
>      VIR_DEBUG("Shutting down VM '%s' pid=%d migrated=%d",
>                vm->def->name, vm->pid, migrated);
> 
> +    if ((logfile = qemudLogFD(driver, vm->def->name)) < 0) {
> +        /* To not break the normal domain shutdown process, skip the
> +         * timestamp log writing if failed on opening log file. */
> +        VIR_WARN("Unable to open logfile: %s",
> +                  virStrerror(errno, ebuf, sizeof ebuf));
> +    } else {
> +        if ((timestamp = virTimestamp()) == NULL) {
> +            virReportOOMError();
> +        } else {
> +            char *shutdownMsg;
> +
> +            if ((virAsprintf(&shutdownMsg, "%s: shutting down\n",
> +                             timestamp)) < 0) {
> +                virReportOOMError();
> +            } else {
> +                if (safewrite(logfile, shutdownMsg, strlen(shutdownMsg)) < 0) {
> +                    VIR_WARN("Unable to write shutdownMsg to logfile: %s",
> +                              virStrerror(errno, ebuf, sizeof ebuf));
> +                }
> +
> +                VIR_FREE(shutdownMsg);
> +            }

This could easily avoid needing to alloc the shutdownMsg, eg

#define POSTFIX ": shutting down\n"

 if (safewrite(logfile, timestamp, strlen(timestamp)) < 0 ||
     safewrite(logfile, POSTFIX, strlen(POSTFIX)) < 0)
    ...


It might be nice to include a ': starting up\n' postfix in the startup
timestamp message too

Regards,
Daniel
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