internal/outcome: rename from app

This is less ambiguous, and more accurately describes the purpose of the package.

Signed-off-by: Ophestra <cat@gensokyo.uk>

1 files changed, 0 insertions, 302 deletions

diff --git a/internal/app/outcome.go b/internal/app/outcome.go
deleted file mode 100644
index 59cdfbd8..00000000
--- a/internal/app/outcome.go
+++ /dev/null
@@ -1,302 +0,0 @@
-package app
-
-import (
-	"errors"
-	"maps"
-	"strconv"
-
-	"hakurei.app/container"
-	"hakurei.app/container/check"
-	"hakurei.app/hst"
-	"hakurei.app/internal/env"
-	"hakurei.app/message"
-	"hakurei.app/system"
-	"hakurei.app/system/acl"
-)
-
-// envAllocSize is the initial size of the env map pre-allocated when the configured env map is nil.
-// It should be large enough to fit all insertions by outcomeOp.toContainer.
-const envAllocSize = 1 << 6
-
-func newInt(v int) *stringPair[int] { return &stringPair[int]{v, strconv.Itoa(v)} }
-
-// stringPair stores a value and its string representation.
-type stringPair[T comparable] struct {
-	v T
-	s string
-}
-
-func (s *stringPair[T]) unwrap() T      { return s.v }
-func (s *stringPair[T]) String() string { return s.s }
-
-// outcomeState is copied to the shim process and available while applying outcomeOp.
-// This is transmitted from the priv side to the shim, so exported fields should be kept to a minimum.
-type outcomeState struct {
-	// Params only used by the shim process. Populated by populateEarly.
-	Shim *shimParams
-
-	// Generated and accounted for by the caller.
-	ID *hst.ID
-	// Copied from ID.
-	id *stringPair[hst.ID]
-
-	// Copied from the [hst.Config] field of the same name.
-	Identity int
-	// Copied from Identity.
-	identity *stringPair[int]
-	// Returned by [Hsu.MustID].
-	UserID int
-	// Target init namespace uid resolved from UserID and identity.
-	uid *stringPair[int]
-
-	// Included as part of [hst.Config], transmitted as-is unless permissive defaults.
-	Container *hst.ContainerConfig
-
-	// Mapped credentials within container user namespace.
-	Mapuid, Mapgid int
-	// Copied from their respective exported values.
-	mapuid, mapgid *stringPair[int]
-
-	// Copied from [EnvPaths] per-process.
-	sc hst.Paths
-	*env.Paths
-
-	// Copied via populateLocal.
-	k syscallDispatcher
-	// Copied via populateLocal.
-	msg message.Msg
-}
-
-// valid checks outcomeState to be safe for use with outcomeOp.
-func (s *outcomeState) valid() bool {
-	return s != nil &&
-		s.Shim.valid() &&
-		s.ID != nil &&
-		s.Container != nil &&
-		s.Paths != nil
-}
-
-// newOutcomeState returns the address of a new outcomeState with its exported fields populated via syscallDispatcher.
-func newOutcomeState(k syscallDispatcher, msg message.Msg, id *hst.ID, config *hst.Config, hsu *Hsu) *outcomeState {
-	s := outcomeState{
-		Shim:      &shimParams{PrivPID: k.getpid(), Verbose: msg.IsVerbose()},
-		ID:        id,
-		Identity:  config.Identity,
-		UserID:    hsu.MustID(msg),
-		Paths:     env.CopyPathsFunc(k.fatalf, k.tempdir, func(key string) string { v, _ := k.lookupEnv(key); return v }),
-		Container: config.Container,
-	}
-
-	// enforce bounds and default early
-	if s.Container.WaitDelay < 0 {
-		s.Shim.WaitDelay = 0
-	} else if s.Container.WaitDelay == 0 {
-		s.Shim.WaitDelay = hst.WaitDelayDefault
-	} else if s.Container.WaitDelay > hst.WaitDelayMax {
-		s.Shim.WaitDelay = hst.WaitDelayMax
-	} else {
-		s.Shim.WaitDelay = s.Container.WaitDelay
-	}
-
-	if s.Container.Flags&hst.FMapRealUID != 0 {
-		s.Mapuid, s.Mapgid = k.getuid(), k.getgid()
-	} else {
-		s.Mapuid, s.Mapgid = k.overflowUid(msg), k.overflowGid(msg)
-	}
-
-	return &s
-}
-
-// populateLocal populates unexported fields from transmitted exported fields.
-// These fields are cheaper to recompute per-process.
-func (s *outcomeState) populateLocal(k syscallDispatcher, msg message.Msg) error {
-	if !s.valid() || k == nil || msg == nil {
-		return newWithMessage("impossible outcome state reached")
-	}
-
-	if s.k != nil || s.msg != nil {
-		panic("attempting to call populateLocal twice")
-	}
-	s.k = k
-	s.msg = msg
-
-	s.id = &stringPair[hst.ID]{*s.ID, s.ID.String()}
-
-	s.Copy(&s.sc, s.UserID)
-	msg.Verbosef("process share directory at %q, runtime directory at %q", s.sc.SharePath, s.sc.RunDirPath)
-
-	s.identity = newInt(s.Identity)
-	s.mapuid, s.mapgid = newInt(s.Mapuid), newInt(s.Mapgid)
-	s.uid = newInt(HsuUid(s.UserID, s.identity.unwrap()))
-
-	return nil
-}
-
-// instancePath returns a path formatted for outcomeStateSys.instance.
-// This method must only be called from outcomeOp.toContainer if
-// outcomeOp.toSystem has already called outcomeStateSys.instance.
-func (s *outcomeState) instancePath() *check.Absolute { return s.sc.SharePath.Append(s.id.String()) }
-
-// runtimePath returns a path formatted for outcomeStateSys.runtime.
-// This method must only be called from outcomeOp.toContainer if
-// outcomeOp.toSystem has already called outcomeStateSys.runtime.
-func (s *outcomeState) runtimePath() *check.Absolute { return s.sc.RunDirPath.Append(s.id.String()) }
-
-// outcomeStateSys wraps outcomeState and [system.I]. Used on the priv side only.
-// Implementations of outcomeOp must not access fields other than sys unless explicitly stated.
-type outcomeStateSys struct {
-	// Whether XDG_RUNTIME_DIR is used post hsu.
-	useRuntimeDir bool
-	// Process-specific directory in TMPDIR, nil if unused.
-	sharePath *check.Absolute
-	// Process-specific directory in XDG_RUNTIME_DIR, nil if unused.
-	runtimeSharePath *check.Absolute
-
-	// Copied from [hst.Config]. Safe for read by outcomeOp.toSystem.
-	appId string
-	// Copied from [hst.Config]. Safe for read by outcomeOp.toSystem.
-	et hst.Enablement
-
-	// Copied from [hst.Config]. Safe for read by spWaylandOp.toSystem only.
-	directWayland bool
-	// Copied header from [hst.Config]. Safe for read by spFilesystemOp.toSystem only.
-	extraPerms []hst.ExtraPermConfig
-	// Copied address from [hst.Config]. Safe for read by spDBusOp.toSystem only.
-	sessionBus, systemBus *hst.BusConfig
-
-	sys *system.I
-	*outcomeState
-}
-
-// newSys returns the address of a new outcomeStateSys embedding the current outcomeState.
-func (s *outcomeState) newSys(config *hst.Config, sys *system.I) *outcomeStateSys {
-	return &outcomeStateSys{
-		appId: config.ID, et: config.Enablements.Unwrap(),
-		directWayland: config.DirectWayland, extraPerms: config.ExtraPerms,
-		sessionBus: config.SessionBus, systemBus: config.SystemBus,
-		sys: sys, outcomeState: s,
-	}
-}
-
-// newParams returns the address of a new outcomeStateParams embedding the current outcomeState.
-func (s *outcomeState) newParams() *outcomeStateParams {
-	stateParams := outcomeStateParams{params: new(container.Params), outcomeState: s}
-	if s.Container.Env == nil {
-		stateParams.env = make(map[string]string, envAllocSize)
-	} else {
-		stateParams.env = maps.Clone(s.Container.Env)
-	}
-	return &stateParams
-}
-
-// ensureRuntimeDir must be called if access to paths within XDG_RUNTIME_DIR is required.
-func (state *outcomeStateSys) ensureRuntimeDir() {
-	if state.useRuntimeDir {
-		return
-	}
-	state.useRuntimeDir = true
-	state.sys.Ensure(state.sc.RunDirPath, 0700)
-	state.sys.UpdatePermType(system.User, state.sc.RunDirPath, acl.Execute)
-	state.sys.Ensure(state.sc.RuntimePath, 0700) // ensure this dir in case XDG_RUNTIME_DIR is unset
-	state.sys.UpdatePermType(system.User, state.sc.RuntimePath, acl.Execute)
-}
-
-// instance returns the pathname to a process-specific directory within TMPDIR.
-// This directory must only hold entries bound to [system.Process].
-func (state *outcomeStateSys) instance() *check.Absolute {
-	if state.sharePath != nil {
-		return state.sharePath
-	}
-	state.sharePath = state.instancePath()
-	state.sys.Ephemeral(system.Process, state.sharePath, 0711)
-	return state.sharePath
-}
-
-// runtime returns the pathname to a process-specific directory within XDG_RUNTIME_DIR.
-// This directory must only hold entries bound to [system.Process].
-func (state *outcomeStateSys) runtime() *check.Absolute {
-	if state.runtimeSharePath != nil {
-		return state.runtimeSharePath
-	}
-	state.ensureRuntimeDir()
-	state.runtimeSharePath = state.runtimePath()
-	state.sys.Ephemeral(system.Process, state.runtimeSharePath, 0700)
-	state.sys.UpdatePerm(state.runtimeSharePath, acl.Execute)
-	return state.runtimeSharePath
-}
-
-// outcomeStateParams wraps outcomeState and [container.Params]. Used on the shim side only.
-type outcomeStateParams struct {
-	// Overrides the embedded [container.Params] in [container.Container]. The Env field must not be used.
-	params *container.Params
-	// Collapsed into the Env slice in [container.Params] by the final outcomeOp.
-	env map[string]string
-
-	// Filesystems with the optional root sliced off if present. Populated by spParamsOp.
-	// Safe for use by spFilesystemOp.
-	filesystem []hst.FilesystemConfigJSON
-
-	// Inner XDG_RUNTIME_DIR default formatting of `/run/user/%d` via mapped uid.
-	// Populated by spRuntimeOp.
-	runtimeDir *check.Absolute
-
-	as hst.ApplyState
-	*outcomeState
-}
-
-// errNotEnabled is returned by outcomeOp.toSystem and used internally to exclude an outcomeOp from transmission.
-var errNotEnabled = errors.New("op not enabled in the configuration")
-
-// An outcomeOp inflicts an outcome on [system.I] and contains enough information to
-// inflict it on [container.Params] in a separate process.
-// An implementation of outcomeOp must store cross-process states in exported fields only.
-type outcomeOp interface {
-	// toSystem inflicts the current outcome on [system.I] in the priv side process.
-	toSystem(state *outcomeStateSys) error
-
-	// toContainer inflicts the current outcome on [container.Params] in the shim process.
-	// The implementation must not write to the Env field of [container.Params] as it will be overwritten
-	// by flattened env map.
-	toContainer(state *outcomeStateParams) error
-}
-
-// toSystem calls the outcomeOp.toSystem method on all outcomeOp implementations and populates shimParams.Ops.
-// This function assumes the caller has already called the Validate method on [hst.Config]
-// and checked that it returns nil.
-func (state *outcomeStateSys) toSystem() error {
-	if state.Shim == nil || state.Shim.Ops != nil {
-		return newWithMessage("invalid ops state reached")
-	}
-
-	ops := [...]outcomeOp{
-		// must run first
-		&spParamsOp{},
-
-		&spRuntimeOp{},
-		spTmpdirOp{},
-		spAccountOp{},
-
-		// optional via enablements
-		&spWaylandOp{},
-		&spX11Op{},
-		&spPulseOp{},
-		&spDBusOp{},
-
-		// must run last
-		&spFilesystemOp{},
-	}
-
-	state.Shim.Ops = make([]outcomeOp, 0, len(ops))
-	for _, op := range ops {
-		if err := op.toSystem(state); err != nil {
-			// this error is used internally to exclude this outcomeOp from transmission
-			if errors.Is(err, errNotEnabled) {
-				continue
-			}
-
-			return err
-		}
-		state.Shim.Ops = append(state.Shim.Ops, op)
-	}
-	return nil
-}