// provisionNode allocates the IDs for one node, meant to be called from a tree
// traversal. If allocation fails, panic and expect to be recovered. The
// allocated IDs are stored in newIds so as to be collected in the recover
// routine.
func provisionNode(g canvas.Graph, this canvas.Node, newIds *[]canvas.NodeIfc) {
Info.Printf("Provisioning %s (%d)\n", this, this.ID())
for _, t := range g.From(this) {
e := g.E(this, t)
target := t.(canvas.Node)
chain := computeChainFrom(this, target)
fid, tid := e.F().Ifc(), e.T().Ifc()
var err error
if fid < 0 {
if fid, err = e.From().(canvas.Node).NewInterfaceID(); err != nil {
Error.Printf("Provisioning %s failed %s\n", e.From().(canvas.Node), err)
panic(err)
}
*newIds = append(*newIds, canvas.NodeIfc{e.From().ID(), fid})
}
if tid < 0 {
if tid, err = e.To().(canvas.Node).NewInterfaceID(); err != nil {
Error.Printf("Provisioning %s failed %s\n", e.To().(canvas.Node), err)
panic(err)
}
*newIds = append(*newIds, canvas.NodeIfc{e.To().ID(), tid})
}
if e.Update(chain, fid, tid) {
}
}
}
