New utils

kernel/bin/uniq

@@ -0,0 +1,167 @@
+/* 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
+}
+
+/**
+ * uniq — filter adjacent duplicate lines from sorted input.
+ */
+async function run(ctx, argv) {
+  let count = false
+  let onlyDup = false
+  let onlyUniq = false
+  const paths = []
+  for (let i = 1; i < argv.length; i++) {
+    const a = argv[i]
+    if (a === '-h' || a === '--help') {
+      ctx.console.log(
+        'usage: uniq [-c] [-d] [-u] [INPUT [OUTPUT]]\n' +
+          '  -c  prefix lines with repeat count\n' +
+          '  -d  only print duplicate lines (one of each group)\n' +
+          '  -u  only print lines that are not repeated\n' +
+          'Reads stdin if INPUT omitted; OUTPUT is ignored (VFS single-output via redirect).'
+      )
+      ctx.exitCode = 0
+      return
+    }
+    if (a === '-c' || a === '--count') {
+      count = true
+      continue
+    }
+    if (a === '-d' || a === '--repeated') {
+      onlyDup = true
+      continue
+    }
+    if (a === '-u' || a === '--unique') {
+      onlyUniq = true
+      continue
+    }
+    if (a.startsWith('-')) {
+      ctx.console.error('uniq: unsupported option ' + a)
+      ctx.exitCode = 1
+      return
+    }
+    paths.push(a)
+  }
+  if (onlyDup && onlyUniq) {
+    ctx.console.error('uniq: -d and -u are mutually exclusive')
+    ctx.exitCode = 1
+    return
+  }
+  let text
+  if (!paths.length) {
+    text = bareStdin(ctx)
+  } else {
+    const b = await ctx.vfs.readFile(paths[0])
+    if (!b) {
+      ctx.console.error('uniq: cannot read ' + paths[0])
+      ctx.exitCode = 1
+      return
+    }
+    text = ctx.b4a.toString(b)
+  }
+  const raw = text.replace(/\r\n/g, '\n')
+  const lines = raw.length ? raw.split('\n') : []
+  if (lines.length && lines[lines.length - 1] === '') lines.pop()
+  let i = 0
+  while (i < lines.length) {
+    let j = i + 1
+    while (j < lines.length && lines[j] === lines[i]) j++
+    const reps = j - i
+    if (onlyDup && reps === 1) {
+      i = j
+      continue
+    }
+    if (onlyUniq && reps > 1) {
+      i = j
+      continue
+    }
+    if (count) ctx.console.log(String(reps) + ' ' + lines[i])
+    else ctx.console.log(lines[i])
+    i = j
+  }
+}