Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*******************************************************************************
* Copyright (c) 2009-2011 Luaj.org. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package org.luaj.vm2
import org.luaj.vm2.internal.*
import org.luaj.vm2.io.*
import org.luaj.vm2.lib.MathLib
import kotlin.jvm.*
import kotlin.native.concurrent.*
/**
* Subclass of [LuaValue] for representing lua strings.
*
*
* Because lua string values are more nearly sequences of bytes than
* sequences of characters or unicode code points, the [LuaString]
* implementation holds the string value in an internal byte array.
*
*
* [LuaString] values are not considered mutable once constructed,
* so multiple [LuaString] values can chare a single byte array.
*
*
* Currently [LuaString]s are pooled via a centrally managed weak table.
* To ensure that as many string values as possible take advantage of this,
* Constructors are not exposed directly. As with number, booleans, and nil,
* instance construction should be via [LuaValue.valueOf] or similar API.
*
*
* Because of this pooling, users of LuaString *must not directly alter the
* bytes in a LuaString*, or undefined behavior will result.
*
*
* When Java Strings are used to initialize [LuaString] data, the UTF8 encoding is assumed.
* The functions
* [.lengthAsUtf8],
* [.encodeToUtf8], and
* [.decodeAsUtf8]
* are used to convert back and forth between UTF8 byte arrays and character arrays.
*
* @see LuaValue
*
* @see LuaValue.valueOf
* @see LuaValue.valueOf
*/
class LuaString
/** Construct a [LuaString] around a byte array without copying the contents.
*
*
* The array is used directly after this is called, so clients must not change contents.
*
*
* @param bytes byte buffer
* @param offset offset into the byte buffer
* @param length length of the byte buffer
* @return [LuaString] wrapping the byte buffer
*/
private constructor(
/** The bytes for the string. These ***must not be mutated directly*** because
* the backing may be shared by multiple LuaStrings, and the hash code is
* computed only at construction time.
* It is exposed only for performance and legacy reasons. */
@kotlin.jvm.JvmField val m_bytes: ByteArray,
/** The offset into the byte array, 0 means start at the first byte */
@kotlin.jvm.JvmField val m_offset: Int,
/** The number of bytes that comprise this string */
@kotlin.jvm.JvmField val m_length: Int
) : LuaValue() {
/** The hashcode for this string. Computed at construct time. */
private val m_hashcode: Int = hashCode(m_bytes, m_offset, m_length)
/** Check that a byte sequence is valid UTF-8
* @return true if it is valid UTF-8, otherwise false
* @see .lengthAsUtf8
* @see .encodeToUtf8
* @see .decodeAsUtf8
*/
val isValidUtf8: Boolean
get() {
var i = m_offset
val j = m_offset + m_length
while (i < j) {
val c = m_bytes[i++].toInt()
if (c >= 0) continue
if (c and 0xE0 == 0xC0
&& i < j
&& m_bytes[i++].toInt() and 0xC0 == 0x80
)
continue
if (c and 0xF0 == 0xE0
&& i + 1 < j
&& m_bytes[i++].toInt() and 0xC0 == 0x80
&& m_bytes[i++].toInt() and 0xC0 == 0x80
)
continue
return false
}
return true
}
override fun isstring(): Boolean = true
override fun getmetatable(): LuaValue? = s_metatable
override fun type(): Int = LuaValue.TSTRING
override fun typename(): String = "string"
override fun tojstring(): String = decodeAsUtf8(m_bytes, m_offset, m_length)
// unary operators
override fun neg(): LuaValue = scannumber().let { d -> if ((d).isNaN()) super.neg() else LuaValue.valueOf(-d) }
// basic binary arithmetic
override fun add(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.ADD, rhs) else rhs.add(d) }
override fun add(rhs: Double): LuaValue = LuaValue.valueOf(checkarith() + rhs)
override fun add(rhs: Int): LuaValue = LuaValue.valueOf(checkarith() + rhs)
override fun sub(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.SUB, rhs) else rhs.subFrom(d) }
override fun sub(rhs: Double): LuaValue = LuaValue.valueOf(checkarith() - rhs)
override fun sub(rhs: Int): LuaValue = LuaValue.valueOf(checkarith() - rhs)
override fun subFrom(lhs: Double): LuaValue = LuaValue.valueOf(lhs - checkarith())
override fun mul(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.MUL, rhs) else rhs.mul(d) }
override fun mul(rhs: Double): LuaValue = LuaValue.valueOf(checkarith() * rhs)
override fun mul(rhs: Int): LuaValue = LuaValue.valueOf(checkarith() * rhs)
override fun pow(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.POW, rhs) else rhs.powWith(d) }
override fun pow(rhs: Double): LuaValue = MathLib.dpow(checkarith(), rhs)
override fun pow(rhs: Int): LuaValue = MathLib.dpow(checkarith(), rhs.toDouble())
override fun powWith(lhs: Double): LuaValue = MathLib.dpow(lhs, checkarith())
override fun powWith(lhs: Int): LuaValue = MathLib.dpow(lhs.toDouble(), checkarith())
override fun div(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.DIV, rhs) else rhs.divInto(d) }
override fun div(rhs: Double): LuaValue = LuaDouble.ddiv(checkarith(), rhs)
override fun div(rhs: Int): LuaValue = LuaDouble.ddiv(checkarith(), rhs.toDouble())
override fun divInto(lhs: Double): LuaValue = LuaDouble.ddiv(lhs, checkarith())
override fun mod(rhs: LuaValue): LuaValue = scannumber().let { d -> if ((d).isNaN()) arithmt(LuaValue.MOD, rhs) else rhs.modFrom(d) }
override fun mod(rhs: Double): LuaValue = LuaDouble.dmod(checkarith(), rhs)
override fun mod(rhs: Int): LuaValue = LuaDouble.dmod(checkarith(), rhs.toDouble())
override fun modFrom(lhs: Double): LuaValue = LuaDouble.dmod(lhs, checkarith())
// relational operators, these only work with other strings
override fun lt(rhs: LuaValue): LuaValue = if (rhs.strcmp(this) > 0) LuaValue.BTRUE else LuaValue.BFALSE
override fun lt_b(rhs: LuaValue): Boolean = rhs.strcmp(this) > 0
override fun lt_b(rhs: Int): Boolean = typerror("attempt to compare string with number")
override fun lt_b(rhs: Double): Boolean = typerror("attempt to compare string with number")
override fun lteq(rhs: LuaValue): LuaValue = if (rhs.strcmp(this) >= 0) LuaValue.BTRUE else LuaValue.BFALSE
override fun lteq_b(rhs: LuaValue): Boolean = rhs.strcmp(this) >= 0
override fun lteq_b(rhs: Int): Boolean = typerror("attempt to compare string with number")
override fun lteq_b(rhs: Double): Boolean = typerror("attempt to compare string with number")
override fun gt(rhs: LuaValue): LuaValue = if (rhs.strcmp(this) < 0) LuaValue.BTRUE else LuaValue.BFALSE
override fun gt_b(rhs: LuaValue): Boolean = rhs.strcmp(this) < 0
override fun gt_b(rhs: Int): Boolean = typerror("attempt to compare string with number")
override fun gt_b(rhs: Double): Boolean = typerror("attempt to compare string with number")
override fun gteq(rhs: LuaValue): LuaValue = if (rhs.strcmp(this) <= 0) LuaValue.BTRUE else LuaValue.BFALSE
override fun gteq_b(rhs: LuaValue): Boolean = rhs.strcmp(this) <= 0
override fun gteq_b(rhs: Int): Boolean = typerror("attempt to compare string with number")
override fun gteq_b(rhs: Double): Boolean = typerror("attempt to compare string with number")
// concatenation
override fun concat(rhs: LuaValue): LuaValue = rhs.concatTo(this)
override fun concat(rhs: Buffer): Buffer = rhs.concatTo(this)
override fun concatTo(lhs: LuaNumber): LuaValue = concatTo(lhs.strvalue()!!)
override fun concatTo(lhs: LuaString): LuaValue {
val b = ByteArray(lhs.m_length + this.m_length)
arraycopy(lhs.m_bytes, lhs.m_offset, b, 0, lhs.m_length)
arraycopy(this.m_bytes, this.m_offset, b, lhs.m_length, this.m_length)
return valueUsing(b, 0, b.size)
}
// string comparison
override fun strcmp(lhs: LuaValue): Int = -lhs.strcmp(this)
override fun strcmp(rhs: LuaString): Int {
var i = 0
var j = 0
while (i < m_length && j < rhs.m_length) {
if (m_bytes[m_offset + i] != rhs.m_bytes[rhs.m_offset + j]) {
return m_bytes[m_offset + i].toInt() - rhs.m_bytes[rhs.m_offset + j].toInt()
}
++i
++j
}
return m_length - rhs.m_length
}
/** Check for number in arithmetic, or throw aritherror */
private fun checkarith(): Double {
val d = scannumber()
if ((d).isNaN()) aritherror()
return d
}
override fun checkint(): Int = checkdouble().toLong().toInt()
override fun checkinteger(): LuaInteger? = LuaValue.valueOf(checkint())
override fun checklong(): Long = checkdouble().toLong()
override fun checkdouble(): Double {
val d = scannumber()
if ((d).isNaN()) argerror("number")
return d
}
override fun checknumber(): LuaNumber? = LuaValue.valueOf(checkdouble())
override fun checknumber(msg: String): LuaNumber {
val d = scannumber()
if ((d).isNaN())
LuaValue.error(msg)
return LuaValue.valueOf(d)
}
override fun isnumber(): Boolean = scannumber().let { d -> !(d.isNaN()) }
override fun isint(): Boolean {
val d = scannumber()
if (d.isNaN())
return false
val i = d.toInt()
return i.toDouble() == d
}
override fun islong(): Boolean {
val d = scannumber()
if ((d.isNaN()))
return false
val l = d.toLong()
return l.toDouble() == d
}
override fun tobyte(): Byte = toint().toByte()
override fun tochar(): Char = toint().toChar()
override fun todouble(): Double = scannumber().let { d -> if ((d.isNaN())) 0.0 else d }
override fun tofloat(): Float = todouble().toFloat()
override fun toint(): Int = tolong().toInt()
override fun tolong(): Long = todouble().toLong()
override fun toshort(): Short = toint().toShort()
override fun optdouble(defval: Double): Double = checknumber()!!.checkdouble()
override fun optint(defval: Int): Int = checknumber()!!.checkint()
override fun optinteger(defval: LuaInteger?): LuaInteger? = checknumber()!!.checkinteger()
override fun optlong(defval: Long): Long = checknumber()!!.checklong()
override fun optnumber(defval: LuaNumber?): LuaNumber? = checknumber()!!.checknumber()
override fun optstring(defval: LuaString?): LuaString? = this
override fun tostring(): LuaValue = this
override fun optjstring(defval: String?): String? = tojstring()
override fun strvalue(): LuaString? = this
/** Take a substring using Java zero-based indexes for begin and end or range.
* @param beginIndex The zero-based index of the first character to include.
* @param endIndex The zero-based index of position after the last character.
* @return LuaString which is a substring whose first character is at offset
* beginIndex and extending for (endIndex - beginIndex ) characters.
*/
fun substring(beginIndex: Int, endIndex: Int): LuaString {
val off = m_offset + beginIndex
val len = endIndex - beginIndex
return if (len >= m_length / 2) valueUsing(m_bytes, off, len) else valueOf(m_bytes, off, len)
}
override fun hashCode(): Int = m_hashcode
// object comparison, used in key comparison
override fun equals(o: Any?): Boolean = if (o is LuaString) raweq(o) else false
// equality w/ metatable processing
override fun eq(`val`: LuaValue): LuaValue = if (`val`.raweq(this)) LuaValue.BTRUE else LuaValue.BFALSE
override fun eq_b(`val`: LuaValue): Boolean = `val`.raweq(this)
// equality w/o metatable processing
override fun raweq(`val`: LuaValue): Boolean = `val`.raweq(this)
override fun raweq(s: LuaString): Boolean {
if (this === s) return true
if (s.m_length != m_length) return false
if (s.m_bytes == m_bytes && s.m_offset == m_offset) return true
if (s.hashCode() != hashCode()) return false
for (i in 0 until m_length) if (s.m_bytes[s.m_offset + i] != m_bytes[m_offset + i]) return false
return true
}
/** Return true if the bytes in the supplied range match this LuaStrings bytes. */
private fun byteseq(bytes: ByteArray, off: Int, len: Int): Boolean = m_length == len && equals(m_bytes, m_offset, bytes, off, len)
fun write(writer: LuaBinOutput, i: Int, len: Int) = writer.write(m_bytes, m_offset + i, len)
override fun len(): LuaValue = LuaInteger.valueOf(m_length)
override fun length(): Int = m_length
override fun rawlen(): Int = m_length
fun luaByte(index: Int): Int = m_bytes[m_offset + index].toInt() and 0x0FF
fun charAt(index: Int): Int {
if (index < 0 || index >= m_length) throw IndexOutOfBoundsException()
return luaByte(index)
}
override fun checkjstring(): String? = tojstring()
override fun checkstring(): LuaString = this
/** Convert value to an input stream.
*
* @return [InputStream] whose data matches the bytes in this [LuaString]
*/
fun toLuaBinInput(): BytesLuaBinInput = BytesLuaBinInput(m_bytes, m_offset, m_length)
/**
* Copy the bytes of the string into the given byte array.
* @param strOffset offset from which to copy
* @param bytes destination byte array
* @param arrayOffset offset in destination
* @param len number of bytes to copy
*/
fun copyInto(strOffset: Int, bytes: ByteArray, arrayOffset: Int, len: Int) =
arraycopy(m_bytes, m_offset + strOffset, bytes, arrayOffset, len)
/** Java version of strpbrk - find index of any byte that in an accept string.
* @param accept [LuaString] containing characters to look for.
* @return index of first match in the `accept` string, or -1 if not found.
*/
fun indexOfAny(accept: LuaString): Int {
val ilimit = m_offset + m_length
val jlimit = accept.m_offset + accept.m_length
for (i in m_offset until ilimit) {
for (j in accept.m_offset until jlimit) {
if (m_bytes[i] == accept.m_bytes[j]) {
return i - m_offset
}
}
}
return -1
}
/**
* Find the index of a byte starting at a point in this string
* @param b the byte to look for
* @param start the first index in the string
* @return index of first match found, or -1 if not found.
*/
fun indexOf(b: Byte, start: Int): Int {
for (i in start until m_length) if (m_bytes[m_offset + i] == b) return i
return -1
}
/**
* Find the index of a string starting at a point in this string
* @param s the string to search for
* @param start the first index in the string
* @return index of first match found, or -1 if not found.
*/
fun indexOf(s: LuaString, start: Int): Int {
val slen = s.length()
val limit = m_length - slen
for (i in start..limit) if (equals(m_bytes, m_offset + i, s.m_bytes, s.m_offset, slen)) return i
return -1
}
/**
* Find the last index of a string in this string
* @param s the string to search for
* @return index of last match found, or -1 if not found.
*/
fun lastIndexOf(s: LuaString): Int {
val slen = s.length()
val limit = m_length - slen
for (i in limit downTo 0) if (equals(m_bytes, m_offset + i, s.m_bytes, s.m_offset, slen)) return i
return -1
}
// --------------------- number conversion -----------------------
/**
* convert to a number using baee 10 or base 16 if it starts with '0x',
* or NIL if it can't be converted
* @return IntValue, DoubleValue, or NIL depending on the content of the string.
* @see LuaValue.tonumber
*/
override fun tonumber(): LuaValue {
val d = scannumber()
return if ((d.isNaN())) LuaValue.NIL else LuaValue.valueOf(d)
}
/**
* convert to a number using a supplied base, or NIL if it can't be converted
* @param base the base to use, such as 10
* @return IntValue, DoubleValue, or NIL depending on the content of the string.
* @see LuaValue.tonumber
*/
fun tonumber(base: Int): LuaValue {
val d = scannumber(base)
return if ((d.isNaN())) LuaValue.NIL else LuaValue.valueOf(d)
}
/**
* Convert to a number in base 10, or base 16 if the string starts with '0x',
* or return Double.NaN if it cannot be converted to a number.
* @return double value if conversion is valid, or Double.NaN if not
*/
fun scannumber(): Double {
var i = m_offset
var j = m_offset + m_length
while (i < j && m_bytes[i] == ' '.toByte()) ++i
while (i < j && m_bytes[j - 1] == ' '.toByte()) --j
if (i >= j)
return Double.NaN
if (m_bytes[i] == '0'.toByte() && i + 1 < j && (m_bytes[i + 1] == 'x'.toByte() || m_bytes[i + 1] == 'X'.toByte()))
return scanlong(16, i + 2, j)
val l = scanlong(10, i, j)
return if ((l.isNaN())) scandouble(i, j) else l
}
/**
* Convert to a number in a base, or return Double.NaN if not a number.
* @param base the base to use between 2 and 36
* @return double value if conversion is valid, or Double.NaN if not
*/
fun scannumber(base: Int): Double {
if (base < 2 || base > 36)
return Double.NaN
var i = m_offset
var j = m_offset + m_length
while (i < j && m_bytes[i] == ' '.toByte()) ++i
while (i < j && m_bytes[j - 1] == ' '.toByte()) --j
return if (i >= j) Double.NaN else scanlong(base, i, j)
}
/**
* Scan and convert a long value, or return Double.NaN if not found.
* @param base the base to use, such as 10
* @param start the index to start searching from
* @param end the first index beyond the search range
* @return double value if conversion is valid,
* or Double.NaN if not
*/
private fun scanlong(base: Int, start: Int, end: Int): Double {
var x: Long = 0
val neg = m_bytes[start] == '-'.toByte()
for (i in (if (neg) start + 1 else start) until end) {
val digit = (m_bytes[i].toInt() and 0xFF) - if (base <= 10 || m_bytes[i] >= '0'.toByte() && m_bytes[i] <= '9'.toByte())
'0'.toInt()
else if (m_bytes[i] >= 'A'.toByte() && m_bytes[i] <= 'Z'.toByte()) 'A'.toInt() - 10 else 'a'.toInt() - 10
if (digit < 0 || digit >= base)
return Double.NaN
x = x * base + digit
if (x < 0)
return Double.NaN // overflow
}
return (if (neg) -x else x).toDouble()
}
/**
* Scan and convert a double value, or return Double.NaN if not a double.
* @param start the index to start searching from
* @param end the first index beyond the search range
* @return double value if conversion is valid,
* or Double.NaN if not
*/
private fun scandouble(start: Int, end: Int): Double {
var end = end
if (end > start + 64) end = start + 64
for (i in start until end) {
when (m_bytes[i].toChar()) {
'-', '+', '.', 'e', 'E', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' -> {
}
else -> return Double.NaN
}
}
val c = CharArray(end - start)
for (i in start until end)
c[i - start] = m_bytes[i].toChar()
try {
return (c.concatToString()).toDouble()
} catch (e: Exception) {
return Double.NaN
}
}
/**
* Print the bytes of the LuaString to a PrintStream as if it were
* an ASCII string, quoting and escaping control characters.
* @param ps PrintStream to print to.
*/
fun printToStream(ps: LuaWriter) {
var i = 0
val n = m_length
while (i < n) {
val c = m_bytes[m_offset + i].toInt()
ps.print(c.toChar())
i++
}
}
companion object {
/** The singleton instance for string metatables that forwards to the string functions.
* Typically, this is set to the string metatable as a side effect of loading the string
* library, and is read-write to provide flexible behavior by default. When used in a
* server environment where there may be roge scripts, this should be replaced with a
* read-only table since it is shared across all lua code in this Java VM.
*/
var s_metatable: LuaValue?
get() = LuaString_metatable
set(value) {
LuaString_metatable = value
}
/** Size of cache of recent short strings. This is the maximum number of LuaStrings that
* will be retained in the cache of recent short strings. Exposed to package for testing. */
const val RECENT_STRINGS_CACHE_SIZE = 128
/** Maximum length of a string to be considered for recent short strings caching.
* This effectively limits the total memory that can be spent on the recent strings cache,
* because no LuaString whose backing exceeds this length will be put into the cache.
* Exposed to package for testing. */
const val RECENT_STRINGS_MAX_LENGTH = 32
/**
* Get a [LuaString] instance whose bytes match
* the supplied Java String using the UTF8 encoding.
* @param string Java String containing characters to encode as UTF8
* @return [LuaString] with UTF8 bytes corresponding to the supplied String
*/
@OptIn(ExperimentalStdlibApi::class)
@JvmName("valueOf2")
fun valueOf(string: String): LuaString {
val c = string.toCharArray()
val b = ByteArray(lengthAsUtf8(c))
encodeToUtf8(c, c.size, b, 0)
return valueUsing(b, 0, b.size)
}
/** Construct a [LuaString] for a portion of a byte array.
*
*
* The array is first be used as the backing for this object, so clients must not change contents.
* If the supplied value for 'len' is more than half the length of the container, the
* supplied byte array will be used as the backing, otherwise the bytes will be copied to a
* new byte array, and cache lookup may be performed.
*
*
* @param bytes byte buffer
* @param off offset into the byte buffer
* @param len length of the byte buffer
* @return [LuaString] wrapping the byte buffer
*/
@JvmName("valueOf2")
fun valueOf(bytes: ByteArray, off: Int, len: Int, runtime: LuaRuntime? = LuaRuntime.default): LuaString {
if (len > RECENT_STRINGS_MAX_LENGTH)
return valueFromCopy(bytes, off, len)
val hash = hashCode(bytes, off, len)
val bucket = hash and RECENT_STRINGS_CACHE_SIZE - 1
val t = runtime?.recent_short_strings?.get(bucket)
if (t != null && t.m_hashcode == hash && t.byteseq(bytes, off, len)) return t
return valueFromCopy(bytes, off, len).also {
if (runtime != null) runtime.recent_short_strings[bucket] = it
}
}
/** Construct a new LuaString using a copy of the bytes array supplied */
private fun valueFromCopy(bytes: ByteArray, off: Int, len: Int): LuaString {
val copy = ByteArray(len)
for (i in 0 until len) copy[i] = bytes[off + i]
return LuaString(copy, 0, len)
}
/** Construct a [LuaString] around, possibly using the the supplied
* byte array as the backing store.
*
*
* The caller must ensure that the array is not mutated after the call.
* However, if the string is short enough the short-string cache is checked
* for a match which may be used instead of the supplied byte array.
*
*
* @param bytes byte buffer
* @return [LuaString] wrapping the byte buffer, or an equivalent string.
*/
@JvmOverloads
fun valueUsing(bytes: ByteArray, off: Int = 0, len: Int = bytes.size, runtime: LuaRuntime? = LuaRuntime.default): LuaString {
if (bytes.size > RECENT_STRINGS_MAX_LENGTH)
return LuaString(bytes, off, len)
val hash = hashCode(bytes, off, len)
val bucket = hash and RECENT_STRINGS_CACHE_SIZE - 1
val t = runtime?.recent_short_strings?.get(bucket)
if (t != null && t.m_hashcode == hash && t.byteseq(bytes, off, len)) return t
return LuaString(bytes, off, len).also {
if (runtime != null) {
runtime.recent_short_strings[bucket] = it
}
}
}
/** Construct a [LuaString] using the supplied characters as byte values.
*
*
* Only the low-order 8-bits of each character are used, the remainder is ignored.
*
*
* This is most useful for constructing byte sequences that do not conform to UTF8.
* @param bytes array of char, whose values are truncated at 8-bits each and put into a byte array.
* @return [LuaString] wrapping a copy of the byte buffer
*/
@JvmOverloads
fun valueOf(bytes: CharArray, off: Int = 0, len: Int = bytes.size): LuaString {
val b = ByteArray(len)
for (i in 0 until len)
b[i] = bytes[i + off].toByte()
return valueUsing(b, 0, len)
}
/** Construct a [LuaString] for all the bytes in a byte array.
*
*
* The LuaString returned will either be a new LuaString containing a copy
* of the bytes array, or be an existing LuaString used already having the same value.
*
*
* @param bytes byte buffer
* @return [LuaString] wrapping the byte buffer
*/
@JvmName("valueOf2")
fun valueOf(bytes: ByteArray): LuaString {
return valueOf(bytes, 0, bytes.size)
}
/** Compute the hash code of a sequence of bytes within a byte array using
* lua's rules for string hashes. For long strings, not all bytes are hashed.
* @param bytes byte array containing the bytes.
* @param offset offset into the hash for the first byte.
* @param length number of bytes starting with offset that are part of the string.
* @return hash for the string defined by bytes, offset, and length.
*/
fun hashCode(bytes: ByteArray, offset: Int, length: Int): Int {
var h = length /* seed */
val step = (length shr 5) + 1 /* if string is too long, don't hash all its chars */
var l1 = length
while (l1 >= step) {
/* compute hash */
h = h xor (h shl 5) + (h shr 2) + (bytes[offset + l1 - 1].toInt() and 0x0FF)
l1 -= step
}
return h
}
fun equals(a: LuaString, i: Int, b: LuaString, j: Int, n: Int): Boolean {
return equals(a.m_bytes, a.m_offset + i, b.m_bytes, b.m_offset + j, n)
}
fun equals(a: ByteArray, i: Int, b: ByteArray, j: Int, n: Int): Boolean {
var i = i
var j = j
var n = n
if (a.size < i + n || b.size < j + n) return false
while (--n >= 0) if (a[i++] != b[j++]) return false
return true
}
/**
* Convert to Java String interpreting as utf8 characters.
*
* @param bytes byte array in UTF8 encoding to convert
* @param offset starting index in byte array
* @param length number of bytes to convert
* @return Java String corresponding to the value of bytes interpreted using UTF8
* @see .lengthAsUtf8
* @see .encodeToUtf8
* @see .isValidUtf8
*/
fun decodeAsUtf8(bytes: ByteArray, offset: Int, length: Int): String {
var i: Int
var j: Int
var n: Int
var b: Int
i = offset
j = offset + length
n = 0
while (i < j) {
when (0xE0 and bytes[i++].toInt()) {
0xE0 -> {
++i
++i
}
0xC0 -> ++i
}
++n
}
val chars = CharArray(n)
i = offset
j = offset + length
n = 0
while (i < j) {
chars[n++] = (if ((run { b = bytes[i++].toInt(); b }) >= 0 || i >= j)
b
else if (b < -32 || i + 1 >= j)
b and 0x3f shl 6 or (bytes[i++].toInt() and 0x3f)
else
b and 0xf shl 12 or (bytes[i++].toInt() and 0x3f shl 6) or (bytes[i++].toInt() and 0x3f)).toChar()
}
return chars.concatToString()
}
/**
* Count the number of bytes required to encode the string as UTF-8.
* @param chars Array of unicode characters to be encoded as UTF-8
* @return count of bytes needed to encode using UTF-8
* @see .encodeToUtf8
* @see .decodeAsUtf8
* @see .isValidUtf8
*/
fun lengthAsUtf8(chars: CharArray): Int {
var i: Int
var c: Char
var b = chars.size
i = b
while (--i >= 0) if ((run { c = chars[i]; c }).toInt() >= 0x80) b += if (c.toInt() >= 0x800) 2 else 1
return b
}
/**
* Encode the given Java string as UTF-8 bytes, writing the result to bytes
* starting at offset.
*
*
* The string should be measured first with lengthAsUtf8
* to make sure the given byte array is large enough.
* @param chars Array of unicode characters to be encoded as UTF-8
* @param nchars Number of characters in the array to convert.
* @param bytes byte array to hold the result
* @param off offset into the byte array to start writing
* @return number of bytes converted.
* @see .lengthAsUtf8
* @see .decodeAsUtf8
* @see .isValidUtf8
*/
fun encodeToUtf8(chars: CharArray, nchars: Int, bytes: ByteArray, off: Int): Int {
var c: Char
var j = off
for (i in 0 until nchars) {
when {
(run { c = chars[i]; c }).toInt() < 0x80 -> bytes[j++] = c.toByte()
c.toInt() < 0x800 -> {
bytes[j++] = (0xC0 or (c.toInt() shr 6 and 0x1f)).toByte()
bytes[j++] = (0x80 or (c.toInt() and 0x3f)).toByte()
}
else -> {
bytes[j++] = (0xE0 or (c.toInt() shr 12 and 0x0f)).toByte()
bytes[j++] = (0x80 or (c.toInt() shr 6 and 0x3f)).toByte()
bytes[j++] = (0x80 or (c.toInt() and 0x3f)).toByte()
}
}
}
return j - off
}
}
}
/** Construct a [LuaString] using the supplied characters as byte values.
*
*
* Only the low-order 8-bits of each character are used, the remainder is ignored.
*
*
* This is most useful for constructing byte sequences that do not conform to UTF8.
* @param bytes array of char, whose values are truncated at 8-bits each and put into a byte array.
* @return [LuaString] wrapping a copy of the byte buffer
*/
/** Construct a [LuaString] for all the bytes in a byte array, possibly using
* the supplied array as the backing store.
*
*
* The LuaString returned will either be a new LuaString containing the byte array,
* or be an existing LuaString used already having the same value.
*
*
* The caller must not mutate the contents of the byte array after this call, as
* it may be used elsewhere due to recent short string caching.
* @param bytes byte buffer
* @return [LuaString] wrapping the byte buffer
*/
@ThreadLocal
private var LuaString_metatable: LuaValue? = null
