[libvirt PATCH v3 05/18] qemu: implement basic virFileCache for nbdkit caps

[Peter Krempa]

On Thu, Oct 20, 2022 at 16:58:56 -0500, Jonathon Jongsma wrote:
> Preparatory step for caching nbdkit capabilities. This patch implements
> the newData and isValid virFileCacheHandlers callback functions.
> 
> Signed-off-by: Jonathon Jongsma <jjongsma at redhat.com>
> ---
>  src/qemu/qemu_nbdkit.c | 93 +++++++++++++++++++++++++++++++++++++++++-
>  src/qemu/qemu_nbdkit.h |  4 ++
>  2 files changed, 96 insertions(+), 1 deletion(-)
> 
> diff --git a/src/qemu/qemu_nbdkit.c b/src/qemu/qemu_nbdkit.c
> index 5de1021d89..9ab048e9e1 100644
> --- a/src/qemu/qemu_nbdkit.c
> +++ b/src/qemu/qemu_nbdkit.c
> @@ -202,7 +202,7 @@ qemuNbdkitGetDirMtime(const char *moddir)
>  }
>  
>  
> -G_GNUC_UNUSED static void
> +static void
>  qemuNbdkitCapsQuery(qemuNbdkitCaps *caps)
>  {
>      struct stat st;
> @@ -241,3 +241,94 @@ qemuNbdkitCapsSet(qemuNbdkitCaps *nbdkitCaps,
>  {
>      ignore_value(virBitmapSetBit(nbdkitCaps->flags, flag));
>  }
> +
> +
> +static bool
> +virNbkditCapsCheckModdir(const char *moddir,
> +                         time_t expectedMtime)
> +{
> +    time_t mtime = qemuNbdkitGetDirMtime(moddir);
> +
> +    if (mtime != expectedMtime) {
> +        VIR_DEBUG("Outdated capabilities for nbdkit: module "
> +                  "directory '%s' changed (%lld vs %lld)",

Preferrably don't use linebreaks in debug/error messages for better
greppability even if it exceeds the "recomended" line lenght. (more
instances in this patch).

Reviewed-by: Peter Krempa <pkrempa at redhat.com>