[libvirt] [PATCH v2] lxc: Include support to lxc version 3.0 or higher.

[John Ferlan]

On 11/5/18 1:57 PM, Julio Faracco wrote:
> This patch introduce the new settings for LXC 3.0 or higher. The older
> versions keep the compatibility to deprecated settings for LXC, but
> after release 3.0, the compatibility was removed. This commit adds the
> support to the refactored settings.
> 
> Signed-off-by: Julio Faracco <jcfaracco at gmail.com>
> ---
>  src/lxc/lxc_native.c | 18 +++++++++++++-----
>  1 file changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/src/lxc/lxc_native.c b/src/lxc/lxc_native.c
> index cbdec723dd..8604cbaf46 100644
> --- a/src/lxc/lxc_native.c
> +++ b/src/lxc/lxc_native.c
> @@ -200,7 +200,9 @@ lxcSetRootfs(virDomainDefPtr def,
>      int type = VIR_DOMAIN_FS_TYPE_MOUNT;
>      VIR_AUTOFREE(char *) value = NULL;
>  
> -    if (virConfGetValueString(properties, "lxc.rootfs", &value) <= 0)
> +    if (virConfGetValueString(properties, "lxc.rootfs", &value) <= 0 &&
> +        /* Legacy config keys were removed after release 3.0. */
> +        virConfGetValueString(properties, "lxc.rootfs.path", &value) <= 0)
>          return -1;

So "integrating" Pino's v2 comment and Michal's RFC/v1 comment plus some
error cleansing:

    if (virConfGetValueString(properties, "lxc.rootfs.path", &value) <= 0) {
        virResetLastError();

        /* Check for pre LXC 3.0 legacy key */
        if (virConfGetValueString(properties, "lxc.rootfs", &value) <= 0)
            return -1;
    }

>  
>      if (STRPREFIX(value, "/dev/"))
> @@ -684,7 +686,9 @@ lxcCreateConsoles(virDomainDefPtr def, virConfPtr properties)
>      virDomainChrDefPtr console;
>      size_t i;
>  
> -    if (virConfGetValueString(properties, "lxc.tty", &value) <= 0)
> +    if (virConfGetValueString(properties, "lxc.tty", &value) <= 0 &&
> +        /* Legacy config keys were removed after release 3.0. */
> +        virConfGetValueString(properties, "lxc.tty.max", &value) <= 0)
>          return 0;

    if (virConfGetValueString(properties, "lxc.tty.max", &value) <= 0) {
        virResetLastError();

        /* Check for pre LXC 3.0 legacy key */
        if (virConfGetValueString(properties, "lxc.tty", &value) <= 0)
            return 0;
    }


Although it could be argued that return 0 should also have a reset last error.

>  
>      if (virStrToLong_i(value, NULL, 10, &nbttys) < 0) {
> @@ -724,7 +728,7 @@ lxcIdmapWalkCallback(const char *name, virConfValuePtr value, void *data)
>      char type;
>      unsigned long start, target, count;
>  
> -    if (STRNEQ(name, "lxc.id_map") || !value->str)
> +    if (STRNEQ(name, "lxc.id_map") || STRNEQ(name, "lxc.idmap") || !value->str)
>          return 0;
>  

    /* LXC 3.0 uses "lxc.idmap", while legacy used "lxc.id_map" */
    if (STRNEQ(name, "lxc.idmap") || STRNEQ(name, "lxc.id_map") || !value->str)
        return 0;

For this one, not only reverse the order, but also fix the error message:

        virReportError(VIR_ERR_INTERNAL_ERROR, _("invalid %s: '%s'"),
                       name, value->str);

where name will be either "lxc.id_map" or "lxc.idmap"

>      if (sscanf(value->str, "%c %lu %lu %lu", &type,
> @@ -1041,7 +1045,9 @@ lxcParseConfigString(const char *config,
>      if (VIR_STRDUP(vmdef->os.init, "/sbin/init") < 0)
>          goto error;
>  
> -    if (virConfGetValueString(properties, "lxc.utsname", &value) <= 0 ||
> +    if ((virConfGetValueString(properties, "lxc.utsname", &value) <= 0 &&
> +         /* Legacy config keys were removed after release 3.0. */
> +         virConfGetValueString(properties, "lxc.uts.name", &value) <= 0) ||
>          VIR_STRDUP(vmdef->name, value) < 0)
>          goto error;

    if (virConfGetValueString(properties, "lxc.uts.name", &value) <= 0) {
        virResetLastError();

        /* Check for pre LXC 3.0 legacy key */
        if (virConfGetValueString(properties, "lxc.utsname", &value) <= 0)
            goto error;
    }
    
    if (VIR_STRDUP(vmdef->name, value) < 0)
        goto error;


>      if (!vmdef->name && (VIR_STRDUP(vmdef->name, "unnamed") < 0))
> @@ -1051,7 +1057,9 @@ lxcParseConfigString(const char *config,
>          goto error;
>  
>      /* Look for fstab: we shouldn't have it */
> -    if (virConfGetValue(properties, "lxc.mount")) {
> +    if (virConfGetValue(properties, "lxc.mount") ||
> +        /* Legacy config keys were removed after release 3.0. */
> +        virConfGetValue(properties, "lxc.mount.fstab")) {
>          virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
>                         _("lxc.mount found, use lxc.mount.entry lines instead"));
>          goto error;
> 

This one's interesting because what does it mean if someone does use "lxc.mount.fstab"?
Should they be using lxc.mount.entry instead?  I assume this is what you want:

    /* LXC 3.0 uses "lxc.mount.fstab", while legacy used just "lxc.mount".
     * In either case, generate the error to use "lxc.mount.entry" instead */
    if (virConfGetValue(properties, "lxc.mount.fstab") || 
        virConfGetValue(properties, "lxc.mount")) {
        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
                       _("lxc.mount.fstab or lxc.mount found, use "
                         "lxc.mount.entry lines instead"));
        goto error;
    }



John