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

/* 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
}

function parseLoggerArgv(argv) {
  let tag = 'logger'
  let prio = 'user.notice'
  let i = 1
  const msg = []
  while (i < argv.length) {
    const a = argv[i]
    if (a === '--') {
      msg.push(...argv.slice(i + 1))
      break
    }
    if (a === '-t') {
      i++
      if (i >= argv.length) return { err: 'logger: option requires an argument -- t' }
      tag = String(argv[i] || '').trim().slice(0, 64) || 'logger'
      i++
      continue
    }
    if (a === '-p') {
      i++
      if (i >= argv.length) return { err: 'logger: option requires an argument -- p' }
      prio = String(argv[i] || '').trim().slice(0, 64) || 'user.notice'
      i++
      continue
    }
    if (a.startsWith('-')) return { err: 'logger: unsupported option ' + a }
    msg.push(...argv.slice(i))
    break
  }
  return { tag, prio, text: msg.join(' ') }
}

async function run(ctx, argv) {
  const p = parseLoggerArgv(argv)
  if (p.err) {
    ctx.console.error(p.err)
    ctx.exitCode = 1
    return
  }
  let text = String(p.text || '')
  if (!text) text = bareStdin(ctx).trim()
  if (!text) {
    ctx.console.error('logger: empty message')
    ctx.exitCode = 1
    return
  }

  const rec = {
    ts: new Date().toISOString(),
    tag: p.tag,
    priority: p.prio,
    message: text
  }
  const line = JSON.stringify(rec) + '\n'
  const maxRaw = Number.parseInt(String(ctx.vfs?.env?.BARE_OS_LOGGER_MAX_BYTES || '1048576'), 10)
  const maxBytes = Number.isFinite(maxRaw) && maxRaw > 1024 ? Math.min(maxRaw, 8 * 1024 * 1024) : 1048576
  let prev = ctx.b4a.from('')
  try {
    const cur = await ctx.vfs.readFile('/var/log/messages')
    if (cur) prev = cur instanceof Uint8Array ? cur : ctx.b4a.from(cur)
  } catch {
    /* new file */
  }
  let next = ctx.b4a.concat([prev, ctx.b4a.from(line, 'utf8')])
  if (next.byteLength > maxBytes) {
    next = next.subarray(next.byteLength - maxBytes)
  }
  await ctx.vfs.writeFile('/var/log/messages', next)
}