bare-operating-system/kernel/bin/find

/* 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
}

/** Session env map (`vfs.env`, then `ctx.env`). Never throws. */
function bareOsEnv(ctx) {
  const v = ctx && ctx.vfs && ctx.vfs.env
  if (v && typeof v === 'object') return v
  const e = ctx && ctx.env
  if (e && typeof e === 'object') return e
  return {}
}

/**
 * Strict POSIX-ish decimal integer (no octal, no exponent, no empty).
 * @param {unknown} s
 * @returns {number}
 */
function bareOsParseDecInt(s) {
  const t = String(s == null ? '' : s).trim()
  if (!/^[+-]?(?:0|[1-9][0-9]*)$/.test(t)) return NaN
  const n = Number.parseInt(t, 10)
  return Number.isSafeInteger(n) ? n : NaN
}

/** @param {unknown} s */
function bareOsParseNonNegInt(s) {
  const n = bareOsParseDecInt(s)
  return n >= 0 ? n : NaN
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} name
 * @param {number} fallback
 * @param {number} [min]
 * @param {number} [max]
 */
function bareOsEnvInt(ctx, name, fallback, min, max) {
  const raw = bareOsEnv(ctx)[name]
  if (raw == null || raw === '') return fallback
  const n = Number.parseInt(String(raw), 10)
  if (!Number.isFinite(n)) return fallback
  let v = n
  if (min != null && v < min) v = min
  if (max != null && v > max) v = max
  return v
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} msg
 * @param {number} [code]
 */
function bareOsFail(ctx, msg, code) {
  if (msg) ctx.console.error(msg)
  ctx.exitCode = code == null ? 1 : code
}

/** @param {unknown} e */
function bareOsIsNotFoundErr(e) {
  const code = e && typeof e === 'object' ? e.code : ''
  if (code === 'ENOENT') return true
  const msg = String((e && e.message) || e || '')
  return /ENOENT|No such file|not found/i.test(msg)
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {unknown} buf
 * @returns {Uint8Array}
 */
function bareOsToU8(ctx, buf) {
  if (!buf) return new Uint8Array(0)
  if (buf instanceof Uint8Array) return buf
  if (ctx && ctx.b4a && typeof ctx.b4a.from === 'function') return ctx.b4a.from(buf)
  return new Uint8Array(buf)
}

/** @param {string} dir @param {string} name */
function bareOsJoinPath(dir, name) {
  const d = String(dir || '').replace(/\/+$/, '')
  const n = String(name || '').replace(/^\/+/, '')
  if (!d || d === '/') return '/' + n
  return d + '/' + n
}

/** @param {string} p */
function bareOsBaseName(p) {
  const t = String(p || '').replace(/\/+$/, '')
  if (!t || t === '/') return t === '/' ? '/' : ''
  const i = t.lastIndexOf('/')
  return i < 0 ? t : t.slice(i + 1) || t
}

/** @param {string} p */
function bareOsParentDir(p) {
  const t = String(p || '').replace(/\/+$/, '') || '/'
  if (t === '/') return '/'
  const i = t.lastIndexOf('/')
  return i <= 0 ? '/' : t.slice(0, i) || '/'
}

/** @param {string} p */
function bareOsNormPath(p) {
  return String(p || '').replace(/\/+$/, '') || '/'
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} p
 */
function bareOsResolvePath(ctx, p) {
  if (ctx && ctx.vfs && typeof ctx.vfs.resolveLogical === 'function') {
    try {
      return String(ctx.vfs.resolveLogical(p) || p)
    } catch {
      /* fall through */
    }
  }
  return String(p || '')
}

/**
 * True when dest is src or lives under src (self-copy / self-move).
 * @param {Record<string, unknown>} ctx
 * @param {string} src
 * @param {string} dest
 */
function bareOsDestInsideSrc(ctx, src, dest) {
  const s = bareOsNormPath(bareOsResolvePath(ctx, src))
  const d = bareOsNormPath(bareOsResolvePath(ctx, dest))
  if (s === d) return true
  if (s === '/') return d !== '/'
  return d === s || d.startsWith(s + '/')
}

const BARE_OS_B64_ALPH =
  'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

/** @param {Uint8Array} u8 */
function bareOsB64Encode(u8) {
  let out = ''
  let i = 0
  for (; i + 2 < u8.length; i += 3) {
    const n = (u8[i] << 16) | (u8[i + 1] << 8) | u8[i + 2]
    out +=
      BARE_OS_B64_ALPH[(n >> 18) & 63] +
      BARE_OS_B64_ALPH[(n >> 12) & 63] +
      BARE_OS_B64_ALPH[(n >> 6) & 63] +
      BARE_OS_B64_ALPH[n & 63]
  }
  const rest = u8.length - i
  if (rest === 1) {
    const n = u8[i] << 16
    out += BARE_OS_B64_ALPH[(n >> 18) & 63] + BARE_OS_B64_ALPH[(n >> 12) & 63] + '=='
  } else if (rest === 2) {
    const n = (u8[i] << 16) | (u8[i + 1] << 8)
    out +=
      BARE_OS_B64_ALPH[(n >> 18) & 63] +
      BARE_OS_B64_ALPH[(n >> 12) & 63] +
      BARE_OS_B64_ALPH[(n >> 6) & 63] +
      '='
  }
  return out
}

/**
 * RFC 4648 Base64 decode (also accepts URL-safe alphabet). Rejects junk.
 * @param {string} s
 * @returns {Uint8Array}
 */
function bareOsB64Decode(s) {
  const t = String(s).replace(/\s+/g, '')
  if (!t) return new Uint8Array(0)
  if (t.length % 4 === 1) throw new Error('invalid base64 length')
  let pad = 0
  if (t.endsWith('==')) pad = 2
  else if (t.endsWith('=')) pad = 1
  const body = pad ? t.slice(0, t.length - pad) : t
  const bytes = []
  let buf = 0
  let bits = 0
  for (let i = 0; i < body.length; i++) {
    const c = body[i]
    let v = BARE_OS_B64_ALPH.indexOf(c)
    if (v < 0) {
      if (c === '-') v = 62
      else if (c === '_') v = 63
      else throw new Error('invalid base64 character')
    }
    buf = (buf << 6) | v
    bits += 6
    if (bits >= 8) {
      bits -= 8
      bytes.push((buf >> bits) & 255)
    }
  }
  if (pad) {
    const want = Math.floor((body.length * 6) / 8)
    if (bytes.length > want) bytes.length = want
  }
  return new Uint8Array(bytes)
}

/**
 * @param {string} s
 * @returns {Uint8Array}
 */
function bareOsHexDecode(s) {
  const t = String(s).replace(/\s+/g, '')
  if (t.length % 2 !== 0) throw new Error('odd hex length')
  const out = new Uint8Array(t.length / 2)
  for (let i = 0; i < out.length; i++) {
    const pair = t.slice(i * 2, i * 2 + 2)
    if (!/^[0-9a-fA-F]{2}$/.test(pair)) throw new Error('invalid hex')
    out[i] = Number.parseInt(pair, 16)
  }
  return out
}

/** @param {Uint8Array} u8 */
function bareOsHexEncode(u8) {
  let s = ''
  for (let i = 0; i < u8.length; i++) s += u8[i].toString(16).padStart(2, '0')
  return s
}

/**
 * curDepth is distance from the search root directory (0 at the initial path).
 * Printed paths use gnu-like depth curDepth + 1 (immediate children of the root are depth 1).
 */
function findEmitLine(ctx, path, print0) {
  if (!print0) {
    ctx.console.log(path)
    return
  }
  if (!bareOsEmitRaw(ctx, path + '\0')) {
    ctx.console.error(
      'find: -print0 requires process.stdout.write or ctx.bareOsBinWrite'
    )
    ctx.exitCode = 1
  }
}

/** @param {string} s */
function parseMtimeSpec(s) {
  const t = String(s)
  let op = ''
  let num = t
  if (t.startsWith('+')) {
    op = '+'
    num = t.slice(1)
  } else if (t.startsWith('-') && t.length > 1) {
    op = '-'
    num = t.slice(1)
  }
  const n = Number.parseFloat(num)
  if (!Number.isFinite(n)) return null
  return { op, n }
}

/** @param {{ op: string, n: number }} spec */
function findMatchMtime(st, spec) {
  const days = (Date.now() - st.mtimeMs) / 86400000
  if (spec.op === '+') return days > spec.n
  if (spec.op === '-') return days < spec.n
  return days >= spec.n && days < spec.n + 1
}

/**
 * Device id sketch for `find -xdev` (do not cross `/mnt/<label>` boundaries vs system/personal).
 * @param {Record<string, unknown>} ctx
 * @param {string} absLogical
 */
function findRouteDevId(ctx, absLogical) {
  const a = String(absLogical).replace(/\/+$/, '') || '/'
  if (a.startsWith('/mnt/')) {
    const label = a.slice(5).split('/').filter(Boolean)[0]
    return label ? `mnt:${label}` : 'mnt:'
  }
  if (a === '/mnt') return 'mnt-root'
  const vfs = ctx.vfs
  if (!vfs || typeof vfs.route !== 'function') return 'unknown'
  const r = vfs.route(absLogical)
  if (r.virtualPseudo) return 'pseudo'
  if (r.virtualHomeDir) return 'personal-home'
  if (r.virtualVarRoot) return 'personal-var'
  if (a.startsWith('/tmp')) return 'personal'
  if (a.startsWith('/home/')) return 'personal'
  if (a.startsWith('/var/')) return 'personal'
  return 'system'
}

/** @param {string} s */
function parsePermSpec(s) {
  const t = String(s).trim()
  if (t.startsWith('/')) return null
  let body = t
  let allBitsSet = false
  if (t.startsWith('-')) {
    allBitsSet = true
    body = t.slice(1)
  }
  if (!/^[0-7]{1,4}$/.test(body)) return null
  const mask = Number.parseInt(body, 8) & 0o7777
  return { allBitsSet, mask }
}

/** @param {Record<string, unknown>} st @param {{ allBitsSet: boolean, mask: number }} spec */
function findMatchPerm(st, spec) {
  const mode =
    typeof st.mode === 'number'
      ? st.mode & 0o7777
      : typeof st.mode === 'string'
        ? Number.parseInt(String(st.mode), 8) & 0o7777
        : 0
  if (spec.allBitsSet) return (mode & spec.mask) === spec.mask
  return mode === spec.mask
}

async function findIsEmpty(ctx, path, st) {
  if (st.type === 'file' || st.type === 'symlink') return (st.size || 0) === 0
  if (st.type !== 'directory') return false
  const names = await ctx.vfs.readdir(path)
  const rest = names.filter((n) => n !== '.bareos_empty')
  return rest.length === 0
}

/**
 * @param {Record<string, unknown>} ctx
 * @param {string} dir
 * @param {Record<string, unknown>} o
 * @param {number} curDepth
 */
async function walk(ctx, dir, o, curDepth) {
  if (o.maxDepth >= 0 && curDepth > o.maxDepth) return
  let names
  try {
    names = await ctx.vfs.readdir(dir)
  } catch (e) {
    ctx.console.error('find: ' + dir + ': ' + ((e && e.message) || e))
    ctx.exitCode = 1
    return
  }
  for (const n of names) {
    if (n === '.bareos_empty') continue
    const path = dir.replace(/\/+$/, '') + '/' + n
    let st
    try {
      st = await ctx.vfs.lstat(path)
    } catch {
      continue
    }
    if (!st) continue
    const gnuDepth = curDepth + 1
    const pathOk = !o.pathRe || o.pathRe.test(path)
    const nameOk = !o.nameRe || o.nameRe.test(n)
    let match = pathOk && nameOk && (!o.wantType || st.type === o.wantType)
    if (match && o.mtimeSpec) match = match && findMatchMtime(st, o.mtimeSpec)
    if (match && o.permSpec) match = match && findMatchPerm(st, o.permSpec)
    if (match && o.newerThanMs != null)
      match = match && st.mtimeMs > o.newerThanMs
    if (match && o.wantEmpty) {
      match = match && (await findIsEmpty(ctx, path, st))
    }
    if (match && o.regexPath && !o.regexPath.test(path)) match = false
    const consider = async () => {
      if (!(match && gnuDepth >= o.minDepth)) return
      if (o.doDelete) {
        if (ctx.vfs.env.BARE_OS_FIND_DELETE !== '1') {
          const stw = /** @type {{ warned?: boolean }} */ (o.deleteState)
          if (!stw.warned) {
            ctx.console.error(
              'find: -delete disabled (set BARE_OS_FIND_DELETE=1 to confirm)'
            )
            stw.warned = true
          }
          ctx.exitCode = 1
        } else {
          try {
            await ctx.vfs.rm(path, { recursive: true, force: true })
          } catch (e) {
            ctx.console.error('find: ' + path + ': ' + (e.message || e))
            ctx.exitCode = 1
          }
        }
      } else if (o.execTemplate && o.execTemplate.length) {
        if (typeof ctx.runBinCommand !== 'function') {
          const stw = /** @type {{ noRun?: boolean }} */ (o.deleteState)
          if (!stw.noRun) {
            ctx.console.error('find: -exec requires ctx.runBinCommand')
            stw.noRun = true
          }
          ctx.exitCode = 1
        } else if (o.execCount >= o.execMax) {
          const stw = /** @type {{ execCap?: boolean }} */ (o.deleteState)
          if (!stw.execCap) {
            ctx.console.error(
              'find: -exec/-ok: invocation limit (' +
                o.execMax +
                ') exceeded (raise BARE_OS_FIND_EXEC_MAX)'
            )
            stw.execCap = true
          }
          ctx.exitCode = 1
        } else {
          const ok =
            !o.execUseOk ||
            ctx.vfs.env.BARE_OS_FIND_OK === '1' ||
            ctx.vfs.env.BARE_OS_FIND_OK === 'true'
          if (o.execUseOk && !ok) {
            /* skip without running */
          } else {
            const subst = o.execTemplate.map((arg) =>
              arg === '{}' ? path : arg.split('{}').join(path)
            )
            o.execCount++
            await ctx.runBinCommand(subst)
          }
        }
      } else {
        findEmitLine(ctx, path, o.print0)
      }
    }
    const shouldRecurse = st.type === 'directory'
    let skipRecurse = false
    if (shouldRecurse) {
      if (o.xdevRootDev != null) {
        const subDev = findRouteDevId(ctx, path)
        if (subDev !== o.xdevRootDev) skipRecurse = true
      }
      const absPath = ctx.vfs.resolveLogical(path)
      if (o.pruneAbs && absPath === o.pruneAbs) skipRecurse = true
    }
    if (!o.depthFirst) await consider()
    if (shouldRecurse && !skipRecurse) await walk(ctx, path, o, curDepth + 1)
    if (o.depthFirst) await consider()
  }
}

async function run(ctx, argv) {
  let maxDepth = -1
  let minDepth = 0
  let depthFirst = false
  /** @type {string | null} */
  let nameGlob = null
  /** @type {string | null} */
  let pathGlob = null
  /** @type {'file' | 'directory' | 'symlink' | null} */
  let wantType = null
  let nameIgnoreCase = false
  let print0 = false
  /** @type {{ op: string, n: number } | null} */
  let mtimeSpec = null
  /** @type {{ allBitsSet: boolean, mask: number } | null} */
  let permSpec = null
  let xdev = false
  /** @type {string | null} */
  let newerPath = null
  /** @type {string | null} */
  let prunePath = null
  let wantEmpty = false
  let doDelete = false
  /** @type {string[] | null} */
  let execTemplate = null
  let execUseOk = false
  /** @type {string | null} */
  let regexPathStr = null
  const rest = []
  for (let i = 1; i < argv.length; i++) {
    const a = argv[i]
    if (a === '-depth') {
      depthFirst = true
      continue
    }
    if (a === '-maxdepth' && argv[i + 1]) {
      maxDepth = bareOsParseNonNegInt(argv[++i])
      if (!Number.isFinite(maxDepth)) {
        ctx.console.error('find: invalid -maxdepth')
        ctx.exitCode = 1
        return
      }
      continue
    }
    if (a === '-mindepth' && argv[i + 1]) {
      minDepth = bareOsParseNonNegInt(argv[++i])
      if (!Number.isFinite(minDepth)) {
        ctx.console.error('find: invalid -mindepth')
        ctx.exitCode = 1
        return
      }
      continue
    }
    if (a === '-path' && argv[i + 1]) {
      pathGlob = argv[++i]
      continue
    }
    if (a === '-name' && argv[i + 1]) {
      nameGlob = argv[++i]
      nameIgnoreCase = false
      continue
    }
    if (a === '-iname' && argv[i + 1]) {
      nameGlob = argv[++i]
      nameIgnoreCase = true
      continue
    }
    if (a === '-type' && argv[i + 1]) {
      const t = argv[++i]
      if (t === 'f') wantType = 'file'
      else if (t === 'd') wantType = 'directory'
      else if (t === 'l') wantType = 'symlink'
      continue
    }
    if (a === '-print0') {
      print0 = true
      continue
    }
    if (a === '-mtime' && argv[i + 1]) {
      mtimeSpec = parseMtimeSpec(argv[++i])
      if (!mtimeSpec) {
        ctx.console.error('find: invalid -mtime')
        ctx.exitCode = 1
        return
      }
      continue
    }
    if (a === '-perm' && argv[i + 1]) {
      permSpec = parsePermSpec(argv[++i])
      if (!permSpec) {
        ctx.console.error('find: invalid -perm')
        ctx.exitCode = 1
        return
      }
      continue
    }
    if (a === '-xdev') {
      xdev = true
      continue
    }
    if (a === '-newer' && argv[i + 1]) {
      newerPath = argv[++i]
      continue
    }
    if (a === '-prune' && argv[i + 1]) {
      prunePath = argv[++i]
      continue
    }
    if (a === '-empty') {
      wantEmpty = true
      continue
    }
    if (a === '-delete') {
      doDelete = true
      continue
    }
    if ((a === '-exec' || a === '-ok') && argv[i + 1]) {
      execUseOk = a === '-ok'
      i++
      const parts = []
      while (i < argv.length && argv[i] !== ';') {
        parts.push(argv[i++])
      }
      if (i >= argv.length || argv[i] !== ';') {
        ctx.console.error('find: ' + a + ' must be terminated with ;')
        ctx.exitCode = 1
        return
      }
      i++
      if (!parts.length) {
        ctx.console.error('find: empty ' + a)
        ctx.exitCode = 1
        return
      }
      execTemplate = parts
      continue
    }
    if (a === '-regex' && argv[i + 1]) {
      const pat = argv[++i]
      try {
        new RegExp(pat)
        regexPathStr = pat
      } catch {
        ctx.console.error('find: invalid -regex')
        ctx.exitCode = 1
        return
      }
      continue
    }
    if (a === '--') {
      rest.push(...argv.slice(i + 1))
      break
    }
    if (a.startsWith('-')) {
      ctx.console.error('find: unsupported ' + a)
      ctx.exitCode = 1
      return
    }
    rest.push(a)
  }
  const root = rest[0] || '.'
  let nameRe = null
  if (nameGlob) {
    const esc = nameGlob
      .replace(/[.+^${}()|[\]\\]/g, '\\$&')
      .replace(/\*/g, '.*')
      .replace(/\?/g, '.')
    nameRe = new RegExp('^' + esc + '$', nameIgnoreCase ? 'i' : '')
  }
  let pathRe = null
  if (pathGlob) {
    const esc = pathGlob
      .replace(/[.+^${}()|[\]\\]/g, '\\$&')
      .replace(/\*\*/g, '\0GLOBSTAR\0')
      .replace(/\*/g, '[^/]*')
      .replace(/\?/g, '[^/]')
      .replace(/\0GLOBSTAR\0/g, '.*')
    pathRe = new RegExp('^' + esc + '$')
  }
  /** @type {number | null} */
  let newerThanMs = null
  if (newerPath) {
    try {
      const st = await ctx.vfs.stat(newerPath)
      if (!st) {
        ctx.console.error('find: ' + newerPath + ': No such file')
        ctx.exitCode = 1
        return
      }
      newerThanMs = st.mtimeMs
    } catch (e) {
      ctx.console.error('find: ' + newerPath + ': ' + (e.message || e))
      ctx.exitCode = 1
      return
    }
  }
  /** @type {string | null} */
  let pruneAbs = null
  if (prunePath) {
    pruneAbs = ctx.vfs.resolveLogical(prunePath).replace(/\/+$/, '') || '/'
  }
  /** @type {RegExp | null} */
  let regexPath = null
  if (regexPathStr) {
    try {
      regexPath = new RegExp(regexPathStr)
    } catch {
      ctx.console.error('find: invalid -regex')
      ctx.exitCode = 1
      return
    }
  }
  const execMaxRaw = ctx.vfs.env.BARE_OS_FIND_EXEC_MAX
  let execMax = 64
  if (execMaxRaw != null && String(execMaxRaw).trim() !== '') {
    const n = Number.parseInt(String(execMaxRaw), 10)
    if (Number.isFinite(n)) execMax = Math.min(4096, Math.max(1, n))
  }
  const abs = ctx.vfs.resolveLogical(root)
  try {
    const stRoot = await ctx.vfs.lstat(abs)
    if (!stRoot) {
      ctx.console.error('find: ' + root + ': No such file or directory')
      ctx.exitCode = 1
      return
    }
  } catch (e) {
    ctx.console.error('find: ' + root + ': ' + ((e && e.message) || String(e)))
    ctx.exitCode = 1
    return
  }
  const xdevRootDev = xdev ? findRouteDevId(ctx, abs) : null
  const o = {
    maxDepth,
    minDepth,
    nameRe,
    pathRe,
    wantType,
    print0,
    mtimeSpec,
    permSpec,
    xdevRootDev,
    newerThanMs,
    pruneAbs,
    wantEmpty,
    doDelete,
    regexPath,
    execTemplate,
    execUseOk,
    execCount: 0,
    execMax,
    deleteState: {},
    depthFirst
  }
  if (minDepth <= 0) {
    try {
      const stRoot = await ctx.vfs.lstat(abs)
      if (stRoot) {
        const pathOk = !o.pathRe || o.pathRe.test(abs)
        const nameOk =
          !o.nameRe || o.nameRe.test(bareOsBaseName(abs) === '/' ? '.' : bareOsBaseName(abs))
        let match = pathOk && nameOk && (!o.wantType || stRoot.type === o.wantType)
        if (match && o.mtimeSpec) match = match && findMatchMtime(stRoot, o.mtimeSpec)
        if (match && o.permSpec) match = match && findMatchPerm(stRoot, o.permSpec)
        if (match && o.newerThanMs != null)
          match = match && stRoot.mtimeMs > o.newerThanMs
        if (match && o.wantEmpty) match = match && (await findIsEmpty(ctx, abs, stRoot))
        if (match && o.regexPath && !o.regexPath.test(abs)) match = false
        if (match && !o.doDelete && !o.execTemplate) {
          if (!depthFirst) findEmitLine(ctx, abs, o.print0)
        }
      }
    } catch {
      /* walk will report */
    }
  }
  await walk(ctx, abs, o, 0)
  if (minDepth <= 0 && depthFirst) {
    try {
      const stRoot = await ctx.vfs.lstat(abs)
      if (stRoot && !o.doDelete && !o.execTemplate) {
        const pathOk = !o.pathRe || o.pathRe.test(abs)
        const nameOk =
          !o.nameRe || o.nameRe.test(bareOsBaseName(abs) === '/' ? '.' : bareOsBaseName(abs))
        if (pathOk && nameOk && (!o.wantType || stRoot.type === o.wantType)) {
          findEmitLine(ctx, abs, o.print0)
        }
      }
    } catch {
      /* already reported */
    }
  }
}