zeroFruit

// UpgradeHandler specifies the type of function that is called when an upgrade
// is applied.
//
// `fromVM` is a VersionMap of moduleName to fromVersion (unit64), where
// fromVersion denotes the version from which we should migrate the module, the
// target version being the module's latest version in the return VersionMap,
// let's call it `toVM`.
//
// `fromVM` is retrieved from x/upgrade's store, whereas `toVM` is chosen
// arbitrarily by the app developer (and persisted to x/upgrade's store right

zeroFruit

func NewSimApp(...) *SimApp {
    ...
    // register the proposal types
    govRouter := govtypes.NewRouter()
    govRouter.AddRoute(govtypes.RouterKey, govtypes.ProposalHandler).
        AddRoute(upgradetypes.RouterKey, upgrade.NewSoftwareUpgradeProposalHandler(app.UpgradeKeeper))
 
    govKeeper := govkeeper.NewKeeper(
        appCodec, keys[govtypes.StoreKey], app.GetSubspace(govtypes.ModuleName), app.AccountKeeper, app.BankKeeper,
        &stakingKeeper, govRouter,

zeroFruit

// EndBlocker called every block, process inflation, update validator set.
func EndBlocker(ctx sdk.Context, keeper keeper.Keeper) {
    keeper.IterateActiveProposalsQueue(ctx, ctx.BlockHeader().Time, func(proposal types.Proposal) bool {
        passes, burnDeposits, tallyResults := keeper.Tally(ctx, proposal)
        ...
      
        if passes {
            handler := keeper.Router().GetRoute(proposal.ProposalRoute())
            cacheCtx, writeCache := ctx.CacheContext()
            err := handler(cacheCtx, proposal.GetContent())

zeroFruit

// SoftwareUpgradeProposal is a gov Content type for initiating a software
// upgrade.
message SoftwareUpgradeProposal {
  string title       = 1;
  string description = 2;
  Plan   plan        = 3 [(gogoproto.nullable) = false];
}

// Plan specifies information about a planned upgrade and when it should occur.
message Plan {

zeroFruit

. # $DAEMON_HOME
├── config
├── cosmovisor
│   ├── current # symbolic link
│   ├── genesis
│   │   └── bin
│   │       └── simappd # $DAEMON_NAME
│   └── upgrades
│       └── v2.0.0 # upgrade name
│           └── bin

zeroFruit

func Build() (host1 *link.Host, host2 *link.Host, host3 *link.Host,
    swch1 *link.Switch, swch2 *link.Switch) {
    // setup node
    // setup interface
    ...
    // setup link
    link1 := link.NewLink(1)
    attachLink(intf1, link1)
    attachLink(sp11, link1)

zeroFruit

func Build() (host1 *link.Host, host2 *link.Host, host3 *link.Host,
    swch1 *link.Switch, swch2 *link.Switch) {
    // setup node
    ...
    // setup interface
    intf1 := link.NewInterface(40001, link.AddrFromStr("11-11-11-11-11-11"), host1)
    attachInterface(host1, intf1)
  
    intf2 := link.NewInterface(40002, link.AddrFromStr("22-22-22-22-22-22"), host2)
    attachInterface(host2, intf2)

zeroFruit

func Build() (host1 *link.Host, host2 *link.Host, host3 *link.Host,
    swch1 *link.Switch, swch2 *link.Switch) {
    // setup node
    host1 = link.NewHost()
    host2 = link.NewHost()
    host3 = link.NewHost()
    swch1 = link.NewSwitch()
    swch2 = link.NewSwitch()
}

zeroFruit

// Forward receives id of port it receives frame, address of sender
// and frame to send to receiver. Based on id and address it determines whether to
// broadcast frame or forward it to others, otherwise just discard frame.
func (s *Switch) Forward(incoming Id, frame na.Frame) error {
    s.Table.Update(incoming, frame.Src)
    frm, err := s.frmEnc.Encode(frame)
    if err != nil {
        return err
    }
    

zeroFruit

// Port can transmit data and can be point of link. But it has no hardware
// address. Before using Port, it must register its own Id
type Port interface {
    Transmitter
    EndPoint
    Register(id Id)
    Registered() bool
}