On 05/14/2014 09:20 PM, Jeff Cody wrote: > Currently, node_name is only filled in when done so explicitly by the > user. If no node_name is specified, then the node name field is not > populated. > > If node_names are automatically generated when not specified, that means > that all block job operations can be done by reference to the unique > node_name field. This eliminates ambiguity in filename pathing
"pathing" sounds weird; a non-native speaker may get confused since it is not a real word. Maybe: This eliminates ambiguity in resolving filenames > (relative filenames, or file descriptors, symlinks, mounts, etc..) that > qemu currently needs to deal with. > > If a node name is specified, then it will not be automatically > generated for that BDS entry. > > If it is automatically generated, it will be prefaced with "__qemu##", > followed by 8 characters of a unique number, followed by 8 random > ASCII characters in the range of 'A-Z'. Some sample generated node-name > strings: > __qemu##00000000IAIYNXXR > __qemu##00000002METXTRBQ > __qemu##00000001FMBORDWG > > The prefix is to aid in identifying it as a qemu-generated name, the > numeric portion is to guarantee uniqueness in a given qemu session, and > the random characters are to further avoid any accidental collisions > with user-specified node-names. > > Signed-off-by: Jeff Cody <[email protected]> > --- > block.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > { > + char gen_node_name[GEN_NODE_NAME_MAX_LEN]; > + static uint32_t counter; /* simple counter to guarantee uniqueness */ > + > + /* if node_name is NULL, auto-generate a node name */ > if (!node_name) { > - return; > + int len; > + snprintf(gen_node_name, GEN_NODE_NAME_MAX_LEN, > + "%s%08x", GEN_NODE_NAME_PREFIX, counter++); > + len = strlen(gen_node_name); Why not just len = snprintf(), and avoid the strlen()? But that micro-optimization is not on the hot path, so: Reviewed-by: Eric Blake <[email protected]> -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
signature.asc
Description: OpenPGP digital signature
