/* Title: Pure/General/bytes.scala
Author: Makarius
Immutable byte vectors versus UTF8 strings.
*/
package isabelle
import java.io.{ByteArrayInputStream, ByteArrayOutputStream, FileInputStream, FileOutputStream,
InputStream, OutputStream, File => JFile}
import java.nio.ByteBuffer
import java.nio.channels.FileChannel
import java.nio.file.StandardOpenOption
import java.util.Arrays
import org.tukaani.xz
import com.github.luben.zstd
import scala.collection.mutable.ArrayBuffer
object Bytes {
/* internal sizes */
val array_size: Long = Int.MaxValue - 8 // see java.io.InputStream.MAX_BUFFER_SIZE
val chunk_size: Long = Space.MiB(100).bytes
val block_size: Int = 8192
class Too_Large(size: Long) extends IndexOutOfBoundsException {
override def getMessage: String =
"Bytes too large for particular operation: " +
Space.bytes(size).print + " > " + Space.bytes(array_size).print
}
/* main constructors */
private def reuse_array(bytes: Array[Byte]): Bytes =
if (bytes.length <= chunk_size) new Bytes(None, bytes, 0L, bytes.length.toLong)
else apply(bytes)
val empty: Bytes = reuse_array(new Array(0))
def apply(s: CharSequence): Bytes = {
val str = s.toString
if (str.isEmpty) empty
else Builder.use(hint = str.length) { builder => builder += str }
}
def apply(a: Array[Byte]): Bytes = apply(a, 0, a.length)
def apply(a: Array[Byte], offset: Int, length: Int): Bytes =
Builder.use(hint = length) { builder => builder += (a, offset, length) }
val newline: Bytes = apply("\n")
def decode_base64(s: String): Bytes = Bytes.reuse_array(Base64.decode(s))
/* read */
def read_stream(stream: InputStream, limit: Long = -1L, hint: Long = 0L): Bytes = {
if (limit == 0) empty
else {
Builder.use(hint = if (limit > 0) limit else hint) { builder =>
val buf = new Array[Byte](Bytes.block_size)
var m = 0
var n = 0L
while ({
val l = if (limit > 0) ((limit - n) min buf.length).toInt else buf.length
m = stream.read(buf, 0, l)
if (m != -1) {
builder += (buf, 0, m)
n += m
}
m != -1 && (limit < 0 || limit > n)
}) ()
}
}
}
def read_url(name: String): Bytes = using(Url(name).open_stream())(read_stream(_))
def read_file(path: Path, offset: Long = 0L, limit: Long = -1L): Bytes = {
val length = File.size(path)
val start = offset.max(0L)
val len = (length - start).max(0L).min(if (limit < 0) Long.MaxValue else limit)
if (len == 0L) empty
else {
Builder.use(hint = len) { builder =>
using(FileChannel.open(path.java_path, StandardOpenOption.READ)) { channel =>
channel.position(start)
val buf = ByteBuffer.allocate(Bytes.block_size)
var m = 0
var n = 0L
while ({
m = channel.read(buf)
if (m != -1) {
builder += (buf.array(), 0, m)
buf.clear()
n += m
}
m != -1 && len > n
}) ()
}
}
}
}
def read(path: Path): Bytes = read_file(path)
def read(file: JFile): Bytes = read_file(File.path(file))
/* write */
def write(file: JFile, bytes: Bytes): Unit =
using(new FileOutputStream(file))(bytes.write_stream(_))
def write(path: Path, bytes: Bytes): Unit = write(path.file, bytes)
/* append */
def append(file: JFile, bytes: Bytes): Unit =
using(new FileOutputStream(file, true))(bytes.write_stream(_))
def append(path: Path, bytes: Bytes): Unit = append(path.file, bytes)
/* vector of short unsigned integers */
trait Vec {
def size: Long
def apply(i: Long): Char
}
class Vec_String(string: String) extends Vec {
override def size: Long = string.length.toLong
override def apply(i: Long): Char =
if (0 <= i && i < size) string(i.toInt)
else throw new IndexOutOfBoundsException
}
/* incremental builder: synchronized */
private def make_size(chunks: Array[Array[Byte]], buffer: Array[Byte]): Long =
chunks.foldLeft(buffer.length.toLong)((n, chunk) => n + chunk.length)
object Builder {
def use(hint: Long = 0L)(body: Builder => Unit): Bytes = {
val chunks_size = if (hint <= 0) 16 else (hint / chunk_size).toInt
val buffer_size = if (hint <= 0) 1024 else (hint min chunk_size min array_size).toInt
val builder = new Builder(chunks_size, buffer_size)
body(builder)
builder.done()
}
}
final class Builder private[Bytes](chunks_size: Int, buffer_size: Int) {
private var chunks = new ArrayBuffer[Array[Byte]](chunks_size)
private var buffer = new ByteArrayOutputStream(buffer_size)
private def buffer_free(): Int = chunk_size.toInt - buffer.size()
private def buffer_check(): Unit =
if (buffer_free() == 0) {
chunks += buffer.toByteArray
buffer = new ByteArrayOutputStream
}
def += (array: Array[Byte], offset: Int, length: Int): Unit = {
if (offset < 0 || length < 0 || offset.toLong + length.toLong > array.length) {
throw new IndexOutOfBoundsException
}
else if (length > 0) {
synchronized {
var i = offset
var n = length
while (n > 0) {
val m = buffer_free()
if (m > 0) {
val l = m min n
buffer.write(array, i, l)
i += l
n -= l
}
buffer_check()
}
}
}
}
def += (array: Array[Byte]): Unit = { this += (array, 0, array.length) }
def += (a: Subarray): Unit = { this += (a.array, a.offset, a.length) }
def += (string: String): Unit = if (string.nonEmpty) { this += UTF8.bytes(string) }
private def done(): Bytes = synchronized {
val cs = chunks.toArray
val b = buffer.toByteArray
chunks = null
buffer = null
new Bytes(if (cs.isEmpty) None else Some(cs), b, 0L, make_size(cs, b))
}
}
/* subarray */
object Subarray {
val empty: Subarray = new Subarray(new Array[Byte](0), 0, 0)
def apply(array: Array[Byte], offset: Int, length: Int): Subarray = {
val n = array.length
if (0 <= offset && offset < n && 0 <= length && offset + length <= n) {
if (length == 0) empty
else new Subarray(array, offset, length)
}
else throw new IndexOutOfBoundsException
}
}
final class Subarray private(
val array: Array[Byte],
val offset: Int,
val length: Int
) {
override def toString: String = "Bytes.Subarray(" + Space.bytes(length).print + ")"
def byte_iterator: Iterator[Byte] =
if (length == 0) Iterator.empty
else { for (i <- (offset until (offset + length)).iterator) yield array(i) }
}
}
final class Bytes private(
protected val chunks: Option[Array[Array[Byte]]],
protected val chunk0: Array[Byte],
protected val offset: Long,
val size: Long
) extends Bytes.Vec {
assert(
(chunks.isEmpty ||
chunks.get.nonEmpty &&
chunks.get.forall(chunk => chunk.length == Bytes.chunk_size)) &&
chunk0.length < Bytes.chunk_size)
def is_empty: Boolean = size == 0
def is_sliced: Boolean =
offset != 0L || {
chunks match {
case None => size != chunk0.length
case Some(cs) => size != Bytes.make_size(cs, chunk0)
}
}
override def toString: String =
if (is_empty) "Bytes.empty"
else "Bytes(" + Space.bytes(size).print + if_proper(is_sliced, ", sliced") + ")"
def small_size: Int =
if (size > Bytes.array_size) throw new Bytes.Too_Large(size)
else size.toInt
/* slice */
def slice(i: Long, j: Long): Bytes =
if (0 <= i && i <= j && j <= size) {
if (i == j) Bytes.empty
else new Bytes(chunks, chunk0, offset + i, j - i)
}
else throw new IndexOutOfBoundsException
def unslice: Bytes =
if (is_sliced) {
Bytes.Builder.use(hint = size) { builder =>
for (a <- subarray_iterator) { builder += a }
}
}
else this
def trim_line: Bytes =
if (size >= 2 && byte_unchecked(size - 2) == 13 && byte_unchecked(size - 1) == 10) {
slice(0, size - 2)
}
else if (size >= 1 && (byte_unchecked(size - 1) == 13 || byte_unchecked(size - 1) == 10)) {
slice(0, size - 1)
}
else this
/* elements: signed Byte or unsigned Char */
protected def byte_unchecked(i: Long): Byte = {
val a = offset + i
chunks match {
case None => chunk0(a.toInt)
case Some(cs) =>
val b = a % Bytes.chunk_size
val c = a / Bytes.chunk_size
if (c < cs.length) cs(c.toInt)(b.toInt) else chunk0(b.toInt)
}
}
def byte(i: Long): Byte =
if (0 <= i && i < size) byte_unchecked(i)
else throw new IndexOutOfBoundsException
def apply(i: Long): Char = (byte(i).toInt & 0xff).toChar
protected def subarray_iterator: Iterator[Bytes.Subarray] =
if (is_empty) Iterator.empty
else if (chunks.isEmpty) Iterator(Bytes.Subarray(chunk0, offset.toInt, size.toInt))
else {
val end_offset = offset + size
for ((array, index) <- (chunks.get.iterator ++ Iterator(chunk0)).zipWithIndex) yield {
val array_start = Bytes.chunk_size * index
val array_stop = array_start + array.length
if (offset < array_stop && array_start < end_offset) {
val i = (array_start max offset) - array_start
val j = (array_stop min end_offset) - array_start
Bytes.Subarray(array, i.toInt, (j - i).toInt)
}
else Bytes.Subarray.empty
}
}
def byte_iterator: Iterator[Byte] =
for {
a <- subarray_iterator
b <- a.byte_iterator
} yield b
/* hash and equality */
lazy val sha1_digest: SHA1.Digest =
if (is_empty) SHA1.digest_empty
else {
SHA1.make_digest { sha =>
for (a <- subarray_iterator if a.length > 0) {
sha.update(a.array, a.offset, a.length)
}
}
}
override def hashCode(): Int = sha1_digest.hashCode()
override def equals(that: Any): Boolean = {
that match {
case other: Bytes =>
if (this.eq(other)) true
else if (size != other.size) false
else if (chunks.isEmpty && size <= 10 * SHA1.digest_length) {
Arrays.equals(chunk0, offset.toInt, (offset + size).toInt,
other.chunk0, other.offset.toInt, (other.offset + other.size).toInt)
}
else sha1_digest == other.sha1_digest
case _ => false
}
}
/* content */
def make_array: Array[Byte] = {
val buf = new ByteArrayOutputStream(small_size)
for (a <- subarray_iterator) { buf.write(a.array, a.offset, a.length) }
buf.toByteArray
}
def text: String =
if (is_empty) ""
else if (byte_iterator.forall(_ >= 0)) {
new String(make_array, UTF8.charset)
}
else UTF8.decode_permissive_bytes(this)
def wellformed_text: Option[String] =
try {
val s = text
if (this == Bytes(s)) Some(s) else None
}
catch { case ERROR(_) => None }
def encode_base64: String = Base64.encode(make_array)
def maybe_encode_base64: (Boolean, String) =
wellformed_text match {
case Some(s) => (false, s)
case None => (true, encode_base64)
}
def proper: Option[Bytes] = if (is_empty) None else Some(this)
def proper_text: Option[String] = if (is_empty) None else Some(text)
def +(other: Bytes): Bytes =
if (other.is_empty) this
else if (is_empty) other
else {
Bytes.Builder.use(hint = size + other.size) { builder =>
for (a <- subarray_iterator ++ other.subarray_iterator) {
builder += a
}
}
}
/* streams */
def stream(): InputStream =
if (chunks.isEmpty) new ByteArrayInputStream(chunk0, offset.toInt, size.toInt)
else {
new InputStream {
private var index = 0L
def read(): Int = {
if (index < size) {
val res = byte_unchecked(index).toInt & 0xff
index += 1
res
}
else -1
}
override def readAllBytes(): Array[Byte] = make_array
}
}
def write_stream(stream: OutputStream): Unit =
for (a <- subarray_iterator if a.length > 0) {
stream.write(a.array, a.offset, a.length)
}
/* XZ / Zstd data compression */
def detect_xz: Boolean =
size >= 6 &&
byte_unchecked(0) == 0xFD.toByte &&
byte_unchecked(1) == 0x37.toByte &&
byte_unchecked(2) == 0x7A.toByte &&
byte_unchecked(3) == 0x58.toByte &&
byte_unchecked(4) == 0x5A.toByte &&
byte_unchecked(5) == 0x00.toByte
def detect_zstd: Boolean =
size >= 4 &&
byte_unchecked(0) == 0x28.toByte &&
byte_unchecked(1) == 0xB5.toByte &&
byte_unchecked(2) == 0x2F.toByte &&
byte_unchecked(3) == 0xFD.toByte
def uncompress_xz(cache: Compress.Cache = Compress.Cache.none): Bytes =
using(new xz.XZInputStream(stream(), cache.for_xz))(Bytes.read_stream(_, hint = size))
def uncompress_zstd(cache: Compress.Cache = Compress.Cache.none): Bytes = {
Zstd.init()
def uncompress_stream(hint: Long): Bytes =
using(new zstd.ZstdInputStream(stream(), cache.for_zstd)) { inp =>
Bytes.read_stream(inp, hint = hint)
}
if (chunks.isEmpty) {
zstd.Zstd.decompressedSize(chunk0, offset.toInt, size.toInt) match {
case 0 => Bytes.empty
case n if n <= Bytes.array_size && !is_sliced =>
Bytes.reuse_array(zstd.Zstd.decompress(chunk0, n.toInt))
case n => uncompress_stream(n)
}
}
else uncompress_stream(size / 2)
}
def uncompress(cache: Compress.Cache = Compress.Cache.none): Bytes =
if (detect_xz) uncompress_xz(cache = cache)
else if (detect_zstd) uncompress_zstd(cache = cache)
else error("Cannot detect compression scheme")
def compress(
options: Compress.Options = Compress.Options(),
cache: Compress.Cache = Compress.Cache.none
): Bytes = {
options match {
case options_xz: Compress.Options_XZ =>
val out = new ByteArrayOutputStream((size min Bytes.array_size).toInt)
using(new xz.XZOutputStream(out, options_xz.make, cache.for_xz))(write_stream)
Bytes(out.toByteArray)
case options_zstd: Compress.Options_Zstd =>
Zstd.init()
val inp = if (chunks.isEmpty && !is_sliced) chunk0 else make_array
Bytes(zstd.Zstd.compress(inp, options_zstd.level))
}
}
def maybe_compress(
options: Compress.Options = Compress.Options(),
cache: Compress.Cache = Compress.Cache.none
) : (Boolean, Bytes) = {
val compressed = compress(options = options, cache = cache)
if (compressed.size < size) (true, compressed) else (false, this)
}
}