refactor(runtime): compose consumers over fs and subprocess

2026-07-28 23:00:00 +08:00
parent 987d477cfc
commit 8917ff8ef4
116 changed files with 2828 additions and 1122 deletions
--- a/packages/subprocess/subprocess-local/src/process-inspector.ts
+++ b/packages/subprocess/subprocess-local/src/process-inspector.ts
@@ -0,0 +1,331 @@
+/** Platform process-table inspection for terminal readiness, signals, and teardown. */
+
+import { closeSync, openSync, readFileSync, readdirSync, readSync } from 'node:fs'
+import { execFileSync } from 'node:child_process'
+import type { SubprocessTerminalSignal } from '@deepseek-ai/dsh-subprocess'
+
+/** PID plus start identity, preventing teardown escalation after PID reuse. */
+export interface ProcessIdentity {
+  pid: number
+  started: string
+}
+
+/** Injectable OS process operations used by one local PTY session. */
+export interface ProcessInspector {
+  foregroundPgid(shellPid: number): number | undefined
+  isStdinWaiting(pgid: number): boolean
+  /** Return the root and its current transitive descendants, children first. */
+  processTree(rootPid: number): ProcessIdentity[]
+  /** Return whether the exact identity remains a non-quiescent process. */
+  isAlive(identity: ProcessIdentity): boolean
+  signalGroup(pgid: number, signal: SubprocessTerminalSignal): void
+  signalProcess(identity: ProcessIdentity, signal: 'SIGTERM' | 'SIGKILL'): void
+}
+
+/** Testable boundary around filesystem, process-table, and signal syscalls. */
+export interface ProcessInspectorInternals {
+  readFile(path: string): string
+  readDir(path: string): string[]
+  open(path: string): number
+  read(fd: number, buffer: Buffer, length: number, position: number): number
+  close(fd: number): void
+  exec(file: string, args: string[]): string
+  kill(pid: number, signal: NodeJS.Signals): void
+}
+
+/* v8 ignore start -- thin OS bindings; injected logic is unit-tested and real platform composition exercises them. */
+const DEFAULT_INTERNALS: ProcessInspectorInternals = {
+  readFile: path => readFileSync(path, 'utf8'),
+  readDir: path => readdirSync(path),
+  open: path => openSync(path, 'r'),
+  read: (fd, buffer, length, position) => readSync(fd, buffer, 0, length, position),
+  close: closeSync,
+  exec: (file, args) => execFileSync(file, args, { encoding: 'utf8' }),
+  kill: (pid, signal) => process.kill(pid, signal),
+}
+/* v8 ignore stop */
+
+interface ProcStat {
+  pid: number
+  parentPid: number
+  pgrp: number
+  session: number
+  state: string
+  tpgid: number
+  started: string
+}
+
+/**
+ * Parse fields used from Linux `/proc/<pid>/stat`, including parenthesized comm text.
+ * @param text - complete stat line.
+ * @returns Parsed identity/group fields, or undefined for malformed input.
+ */
+export function parseProcStat(text: string): ProcStat | undefined {
+  const open = text.indexOf('(')
+  const close = text.lastIndexOf(')')
+  if (open <= 0 || close <= open) return undefined
+  const pid = Number(text.slice(0, open).trim())
+  const rest = text.slice(close + 2).trim().split(/\s+/)
+  const state = rest[0] || ''
+  const parentPid = Number(rest[1])
+  const pgrp = Number(rest[2])
+  const session = Number(rest[3])
+  const tpgid = Number(rest[5])
+  const started = rest[19]
+  if (![pid, parentPid, pgrp, session, tpgid].every(Number.isSafeInteger)
+    || state.length !== 1 || started === undefined) return undefined
+  return { pid, parentPid, pgrp, session, state, tpgid, started }
+}
+
+function readLinuxStat(internals: ProcessInspectorInternals, pid: number): ProcStat | undefined {
+  try {
+    return parseProcStat(internals.readFile(`/proc/${pid}/stat`))
+  } catch (_unreadableProcEntry) {
+    return undefined
+  }
+}
+
+function numericEntries(internals: ProcessInspectorInternals, path: string): number[] {
+  try {
+    return internals.readDir(path).filter(entry => /^\d+$/.test(entry)).map(Number)
+  } catch (_unreadableProcDirectory) {
+    return []
+  }
+}
+
+interface SyscallInfo {
+  number: number
+  args: number[]
+}
+
+function readSyscall(internals: ProcessInspectorInternals, pid: number, tid: number): SyscallInfo | undefined {
+  try {
+    const text = internals.readFile(`/proc/${pid}/task/${tid}/syscall`).trim()
+    if (text === 'running' || text.startsWith('-1 ')) return undefined
+    const fields = text.split(/\s+/)
+    const number = Number(fields[0])
+    const args = fields.slice(1, 7).map(field => Number.parseInt(field, 16))
+    if (!Number.isSafeInteger(number) || args.some(value => !Number.isSafeInteger(value))) return undefined
+    return { number, args }
+  } catch (_unreadableSyscall) {
+    return undefined
+  }
+}
+
+function readMemory(
+  internals: ProcessInspectorInternals,
+  pid: number,
+  address: number,
+  length: number,
+): Buffer | undefined {
+  let fd: number | undefined
+  try {
+    fd = internals.open(`/proc/${pid}/mem`)
+    const buffer = Buffer.alloc(length)
+    const count = internals.read(fd, buffer, length, address)
+    return buffer.subarray(0, count)
+  } catch (_unreadableProcessMemory) {
+    return undefined
+  } finally {
+    if (fd !== undefined) internals.close(fd)
+  }
+}
+
+function fdSetHasStdin(internals: ProcessInspectorInternals, pid: number, address: number): boolean {
+  return address !== 0 && (readMemory(internals, pid, address, 8)?.[0] ?? 0) % 2 === 1
+}
+
+function pollHasStdin(
+  internals: ProcessInspectorInternals,
+  pid: number,
+  address: number,
+  count: number,
+): boolean {
+  if (address === 0 || count <= 0) return false
+  const memory = readMemory(internals, pid, address, Math.min(count, 1024) * 8)
+  if (memory === undefined) return false
+  for (let offset = 0; offset + 8 <= memory.length; offset += 8) {
+    if (memory.readInt32LE(offset) === 0 && (memory.readInt16LE(offset + 4) & 0x001) !== 0) return true
+  }
+  return false
+}
+
+function epollHasStdin(internals: ProcessInspectorInternals, pid: number, epfd: number): boolean {
+  try {
+    return internals.readFile(`/proc/${pid}/fdinfo/${epfd}`)
+      .split('\n')
+      .some(line => /^tfd:\s+0\b/.test(line.trim()))
+  } catch (_unreadableFdInfo) {
+    return false
+  }
+}
+
+interface SyscallTable {
+  read: number
+  select?: number
+  pselect: number
+  poll?: number
+  ppoll: number
+  epollWait?: number
+  epollPwait: number
+}
+
+const SYSCALLS: Partial<Record<NodeJS.Architecture, SyscallTable>> = {
+  x64: { read: 0, select: 23, pselect: 270, poll: 7, ppoll: 271, epollWait: 232, epollPwait: 281 },
+  arm64: { read: 63, pselect: 72, ppoll: 73, epollPwait: 22 },
+}
+
+function syscallWaitsOnStdin(
+  internals: ProcessInspectorInternals,
+  pid: number,
+  syscall: SyscallInfo,
+  table: SyscallTable,
+): boolean {
+  const [a0 = 0, a1 = 0, a2 = 0] = syscall.args
+  if (syscall.number === table.read) return a0 === 0
+  if (syscall.number === table.select || syscall.number === table.pselect) {
+    return a0 >= 1 && fdSetHasStdin(internals, pid, a1)
+  }
+  if (syscall.number === table.poll || syscall.number === table.ppoll) {
+    return a1 >= 1 && pollHasStdin(internals, pid, a0, a1)
+  }
+  if (syscall.number === table.epollWait || syscall.number === table.epollPwait) {
+    return a2 >= 1 && epollHasStdin(internals, pid, a0)
+  }
+  return false
+}
+
+abstract class PosixProcessInspector implements ProcessInspector {
+  constructor(protected readonly internals: ProcessInspectorInternals) {}
+
+  abstract foregroundPgid(shellPid: number): number | undefined
+  abstract isStdinWaiting(pgid: number): boolean
+  abstract processTree(rootPid: number): ProcessIdentity[]
+  abstract isAlive(identity: ProcessIdentity): boolean
+
+  signalGroup(pgid: number, signal: SubprocessTerminalSignal): void {
+    this.internals.kill(-pgid, signal)
+  }
+
+  signalProcess(identity: ProcessIdentity, signal: 'SIGTERM' | 'SIGKILL'): void {
+    if (this.isAlive(identity)) this.internals.kill(identity.pid, signal)
+  }
+}
+
+interface ProcessTreeEntry extends ProcessIdentity {
+  parentPid: number
+}
+
+function processTree(entries: ProcessTreeEntry[], rootPid: number): ProcessIdentity[] {
+  const byPid = new Map(entries.map(entry => [entry.pid, entry]))
+  const root = byPid.get(rootPid)
+  if (root === undefined) return []
+  const byParent = new Map<number, ProcessTreeEntry[]>()
+  for (const entry of entries) {
+    const children = byParent.get(entry.parentPid) ?? []
+    children.push(entry)
+    byParent.set(entry.parentPid, children)
+  }
+  const visited = new Set<number>()
+  const result: ProcessIdentity[] = []
+  const visit = (entry: ProcessTreeEntry): void => {
+    if (visited.has(entry.pid)) return
+    visited.add(entry.pid)
+    for (const child of byParent.get(entry.pid) ?? []) visit(child)
+    result.push({ pid: entry.pid, started: entry.started })
+  }
+  visit(root)
+  return result
+}
+
+class LinuxProcessInspector extends PosixProcessInspector {
+  constructor(
+    private readonly arch: NodeJS.Architecture,
+    internals: ProcessInspectorInternals,
+  ) {
+    super(internals)
+  }
+
+  foregroundPgid(shellPid: number): number | undefined {
+    const tpgid = readLinuxStat(this.internals, shellPid)?.tpgid
+    return tpgid !== undefined && tpgid > 0 ? tpgid : undefined
+  }
+
+  isStdinWaiting(pgid: number): boolean {
+    const table = SYSCALLS[this.arch]
+    if (table === undefined) return false
+    for (const pid of numericEntries(this.internals, '/proc')) {
+      if (readLinuxStat(this.internals, pid)?.pgrp !== pgid) continue
+      for (const tid of numericEntries(this.internals, `/proc/${pid}/task`)) {
+        const syscall = readSyscall(this.internals, pid, tid)
+        if (syscall !== undefined && syscallWaitsOnStdin(this.internals, pid, syscall, table)) return true
+      }
+    }
+    return false
+  }
+
+  processTree(rootPid: number): ProcessIdentity[] {
+    const entries = numericEntries(this.internals, '/proc').flatMap((pid) => {
+      const stat = readLinuxStat(this.internals, pid)
+      return stat === undefined ? [] : [{ pid, parentPid: stat.parentPid, started: stat.started }]
+    })
+    return processTree(entries, rootPid)
+  }
+
+  isAlive(identity: ProcessIdentity): boolean {
+    const stat = readLinuxStat(this.internals, identity.pid)
+    return stat?.started === identity.started && !/^[ZXx]$/.test(stat.state)
+  }
+
+}
+
+interface PsEntry extends ProcessTreeEntry {}
+
+function macProcessTable(internals: ProcessInspectorInternals): PsEntry[] {
+  return internals.exec('/bin/ps', ['-axo', 'pid=,ppid=,lstart=']).split('\n').flatMap((line) => {
+    const match = /^\s*(\d+)\s+(\d+)\s+(.+?)\s*$/.exec(line)
+    if (match?.[1] === undefined || match[2] === undefined || match[3] === undefined) return []
+    return [{ pid: Number(match[1]), parentPid: Number(match[2]), started: match[3] }]
+  })
+}
+
+class MacProcessInspector extends PosixProcessInspector {
+  foregroundPgid(shellPid: number): number | undefined {
+    try {
+      const value = Number(this.internals.exec('/bin/ps', ['-o', 'tpgid=', '-p', String(shellPid)]).trim())
+      return Number.isSafeInteger(value) && value > 0 ? value : undefined
+    } catch (_missingProcess) {
+      return undefined
+    }
+  }
+
+  isStdinWaiting(_pgid: number): boolean {
+    return false
+  }
+
+  processTree(rootPid: number): ProcessIdentity[] {
+    return processTree(macProcessTable(this.internals), rootPid)
+  }
+
+  isAlive(identity: ProcessIdentity): boolean {
+    return macProcessTable(this.internals).some(entry => entry.pid === identity.pid && entry.started === identity.started)
+  }
+
+}
+
+/**
+ * Create the supported platform inspector or fail at plugin load.
+ * @param platform - target Node platform.
+ * @param arch - target CPU architecture for Linux syscall numbers.
+ * @param internals - filesystem/process boundary, injectable for deterministic tests.
+ * @returns Platform process inspector.
+ */
+export function createProcessInspector(
+  platform: NodeJS.Platform = process.platform,
+  arch: NodeJS.Architecture = process.arch,
+  internals: ProcessInspectorInternals = DEFAULT_INTERNALS,
+): ProcessInspector {
+  if (platform === 'linux') return new LinuxProcessInspector(arch, internals)
+  if (platform === 'darwin') return new MacProcessInspector(internals)
+  throw new Error(`subprocess-local: terminal inspection is unsupported on platform ${platform}`)
+}