bare-operating-system/packages/bare-os-seeder/kernel/bin/test

/* BARE_OS_BIN_API 1.0.0 — bump when staged /bin script semantics change (see developer guide). */
/** Shared helpers for drive-resident /bin scripts (prepended before each command). */
function bareStdin(ctx) {
  return typeof ctx.shellStdin === 'string' ? ctx.shellStdin : ''
}

/** @param {number} mode @param {'file' | 'directory' | 'symlink'} type */
function bareFormatModeString(mode, type) {
  const typeChar = type === 'directory' ? 'd' : type === 'symlink' ? 'l' : '-'
  const perm = mode & 0o777
  const r = (bit) => (perm & bit ? 'r' : '-')
  const w = (bit) => (perm & bit ? 'w' : '-')
  const x = (bit) => (perm & bit ? 'x' : '-')
  return (
    typeChar +
    r(0o400) +
    w(0o200) +
    x(0o100) +
    r(0o040) +
    w(0o020) +
    x(0o010) +
    r(0o004) +
    w(0o002) +
    x(0o001)
  )
}

/** @param {number} mtimeMs @param {number} [nowMs] */
function bareFormatLsMtime(mtimeMs, nowMs) {
  const now = nowMs != null ? nowMs : Date.now()
  const d = new Date(mtimeMs)
  const months = [
    'Jan',
    'Feb',
    'Mar',
    'Apr',
    'May',
    'Jun',
    'Jul',
    'Aug',
    'Sep',
    'Oct',
    'Nov',
    'Dec'
  ]
  const mon = months[d.getMonth()]
  const day = String(d.getDate()).padStart(2, ' ')
  const sixMo = 180 * 24 * 3600 * 1000
  if (Math.abs(now - mtimeMs) > sixMo) {
    const yr = String(d.getFullYear()).padStart(4, ' ')
    return mon + ' ' + day + '  ' + yr
  }
  const hh = String(d.getHours()).padStart(2, '0')
  const mm = String(d.getMinutes()).padStart(2, '0')
  return mon + ' ' + day + ' ' + hh + ':' + mm
}

/** @param {number} size */
function barePosixBlocks(size) {
  return Math.ceil(Number(size) / 512) || 0
}

/**
 * Raw stdout for NUL/binary when **`process.stdout.write`** is missing.
 * If **`ctx.bareOsBinWrite(Uint8Array|string)`** is set (tests / host), use it.
 * @param {Record<string, unknown>} ctx
 * @param {string | Uint8Array} chunk
 * @returns {boolean}
 */
function bareOsEmitRaw(ctx, chunk) {
  if (typeof ctx.bareOsBinWrite === 'function') {
    const b4 = ctx.b4a
    const u8 =
      typeof chunk === 'string'
        ? b4 && typeof b4.from === 'function'
          ? b4.from(chunk)
          : new TextEncoder().encode(chunk)
        : chunk
    ctx.bareOsBinWrite(u8 instanceof Uint8Array ? u8 : new Uint8Array(u8))
    return true
  }
  const w = globalThis.process?.stdout?.write
  if (typeof w === 'function') {
    w.call(globalThis.process.stdout, chunk)
    return true
  }
  return false
}

/** @param {string | number} s */
function parseBareOsTestInt(s) {
  const t = String(s).trim()
  if (t === '' || t === '+' || t === '-') return NaN
  if (!/^[+-]?(?:0|[1-9][0-9]*)$/.test(t)) return NaN
  const n = Number.parseInt(t, 10)
  return Number.isSafeInteger(n) ? n : NaN
}

/** @param {Record<string, unknown>} ctx */
function testParseEuidEgid(ctx) {
  const e = (ctx.vfs && ctx.vfs.env) || ctx.env || {}
  const uid = Number.parseInt(String(e.UID != null ? e.UID : '1000'), 10)
  const gid = Number.parseInt(String(e.GID != null ? e.GID : '1000'), 10)
  return {
    euid: Number.isFinite(uid) ? uid : 1000,
    egid: Number.isFinite(gid) ? gid : 1000
  }
}

/**
 * User/group/other permission triplet (0–7) for the effective uid/gid.
 * @param {Record<string, unknown>} st
 * @param {number} euid
 * @param {number} egid
 */
function testEffPermTriplet(st, euid, egid) {
  const mode =
    typeof st.mode === 'number'
      ? st.mode & 0o777
      : Number.parseInt(String(st.mode || '644'), 8) & 0o777
  const fuid = st.uid != null ? Number(st.uid) : 0
  const fgid = st.gid != null ? Number(st.gid) : 0
  if (euid === fuid) return (mode >> 6) & 7
  if (egid === fgid) return (mode >> 3) & 7
  return mode & 7
}

async function evalTest(ctx, args) {
  if (!args.length) return false
  if (args[0] === '!') {
    const inner = await evalTest(ctx, args.slice(1))
    return !inner
  }
  if (args.length === 3) {
    const [a, op, b] = args
    if (op === '-eq' || op === '-ne' || op === '-lt' || op === '-le' || op === '-gt' || op === '-ge') {
      const la = parseBareOsTestInt(a)
      const lb = parseBareOsTestInt(b)
      if (!Number.isFinite(la) || !Number.isFinite(lb)) return false
      switch (op) {
        case '-eq':
          return la === lb
        case '-ne':
          return la !== lb
        case '-lt':
          return la < lb
        case '-le':
          return la <= lb
        case '-gt':
          return la > lb
        case '-ge':
          return la >= lb
        default:
          return false
      }
    }
    if (op === '=') return a === b
    if (op === '!=') return a !== b
    return false
  }
  if (args.length === 2) {
    const op = args[0]
    const p = args[1]
    if (op === '-h' || op === '-L') {
      const st = await ctx.vfs.lstat(p)
      return st != null && st.type === 'symlink'
    }
    const { euid, egid } = testParseEuidEgid(ctx)
    const st = await ctx.vfs.stat(p)
    if (op === '-e' || op === '-a') return st != null
    if (op === '-f') return st != null && st.type === 'file'
    if (op === '-d') return st != null && st.type === 'directory'
    if (op === '-r')
      return st != null && (testEffPermTriplet(st, euid, egid) & 4) !== 0
    if (op === '-w')
      return st != null && (testEffPermTriplet(st, euid, egid) & 2) !== 0
    if (op === '-x')
      return st != null && (testEffPermTriplet(st, euid, egid) & 1) !== 0
    if (st != null) {
      const m =
        typeof st.mode === 'number'
          ? st.mode
          : Number.parseInt(String(st.mode || '0'), 8) || 0
      if (op === '-u') return (m & 0o4000) !== 0
      if (op === '-g') return (m & 0o2000) !== 0
      if (op === '-k') return (m & 0o1000) !== 0
    }
    if (op === '-s')
      return st != null && st.type === 'file' && Number(st.size) > 0
    if (op === '-z') return p.length === 0
    if (op === '-n') return p.length > 0
    return false
  }
  if (args.length === 1) return args[0] !== ''
  return false
}

async function run(ctx, argv) {
  ctx.exitCode = (await evalTest(ctx, argv.slice(1))) ? 0 : 1
}