-
Notifications
You must be signed in to change notification settings - Fork 1.5k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
util: Make
ProxyByteReader and ProxyByteWriter Public
Problem `ProxyByteReader` is incredibly useful for reading specialized information out of a `Buf` while still benefitting from all the already existing goodness that comes for free from the `ByteReader` implementation. However, it is not currently accessible to code outside of the `com.twitter` namespace. Solution Make `ProxyByteReader` and `ProxyByteWriter` both public, and modify `ProxyByteReader`s structure so that it aligns with `ProxyByteWriter`. Differential Revision: https://phabricator.twitter.biz/D622705
- Loading branch information
1 parent
ca67793
commit ad73f92
Showing
5 changed files
with
217 additions
and
174 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
116 changes: 116 additions & 0 deletions
116
finagle-mysql/src/main/scala/com/twitter/finagle/mysql/transport/MysqlBufReader.scala
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,116 @@ | ||
| package com.twitter.finagle.mysql.transport | ||
|
|
||
| import com.twitter.io.{Buf, ByteReader, ProxyByteReader} | ||
| import java.nio.charset.{StandardCharsets, Charset => JCharset} | ||
| import scala.collection.mutable.{Buffer => MutableBuffer} | ||
|
|
||
| /** | ||
| * A `ByteReader` specialized for dealing with MySQL protocol messages. | ||
| */ | ||
| class MysqlBufReader(underlying: ByteReader) extends ProxyByteReader(underlying) { | ||
| import MysqlBuf._ | ||
|
|
||
| /** | ||
| * Take `n` bytes as a byte array | ||
| */ | ||
| def take(n: Int): Array[Byte] = { | ||
| Buf.ByteArray.Owned.extract(readBytes(n)) | ||
| } | ||
|
|
||
| /** | ||
| * Reads bytes until a null byte is encountered | ||
| */ | ||
| def readNullTerminatedBytes(): Array[Byte] = { | ||
| val bytes = MutableBuffer[Byte]() | ||
| var eof = false | ||
| do { | ||
| val b = readByte() | ||
| if (b == 0x00) { | ||
| eof = true | ||
| } else { | ||
| bytes += b | ||
| } | ||
| } while (!eof) | ||
| bytes.toArray | ||
| } | ||
|
|
||
| /** | ||
| * Reads a null-terminated UTF-8 encoded string | ||
| */ | ||
| def readNullTerminatedString(): String = | ||
| new String(readNullTerminatedBytes(), StandardCharsets.UTF_8) | ||
|
|
||
| /** | ||
| * Reads a length encoded set of bytes according to the MySQL | ||
| * Client/Server protocol. This is identical to a length coded | ||
| * string except the bytes are returned raw. | ||
| * | ||
| * @return Array[Byte] if length is non-null, or null otherwise. | ||
| */ | ||
| def readLengthCodedBytes(): Array[Byte] = { | ||
| readVariableLong() match { | ||
| case NullLength => null | ||
| case 0 => Array.emptyByteArray | ||
| case len if len > Int.MaxValue => | ||
| throw new IllegalStateException(s"Length-encoded byte size is too large: $len") | ||
| case len => Buf.ByteArray.Owned.extract(readBytes(len.toInt)) | ||
| } | ||
| } | ||
|
|
||
| /** | ||
| * Reads a length encoded string according to the MySQL | ||
| * Client/Server protocol. Uses `charset` to decode the string. | ||
| * For more details refer to MySQL documentation. | ||
| * | ||
| * @return a MySQL length coded String starting at | ||
| * offset. | ||
| */ | ||
| def readLengthCodedString(charset: JCharset): String = { | ||
| val bytes = readLengthCodedBytes() | ||
| if (bytes != null) { | ||
| new String(bytes, charset) | ||
| } else { | ||
| null | ||
| } | ||
| } | ||
|
|
||
| /** | ||
| * Reads a variable-length numeric value. | ||
| * Depending on the first byte, reads a different width from | ||
| * the buffer. For more info, refer to MySQL Client/Server protocol | ||
| * documentation. | ||
| * | ||
| * @return a numeric value representing the number of | ||
| * bytes expected to follow. | ||
| */ | ||
| def readVariableLong(): Long = { | ||
| readUnsignedByte() match { | ||
| case len if len < 251 => len | ||
| case 251 => NullLength | ||
| case 252 => readUnsignedShortLE() | ||
| case 253 => readUnsignedMediumLE() | ||
| case 254 => | ||
| val longValue = readLongLE() | ||
| if (longValue < 0) | ||
| throw new IllegalStateException(s"Negative length-encoded value: $longValue") | ||
| longValue | ||
|
|
||
| case len => throw new IllegalStateException(s"Invalid length byte: $len") | ||
| } | ||
| } | ||
| } | ||
|
|
||
| object MysqlBufReader { | ||
|
|
||
| /** | ||
| * Create a new [[MysqlBufReader]] from an existing `Buf`. | ||
| */ | ||
| def apply(buf: Buf): MysqlBufReader = | ||
| new MysqlBufReader(ByteReader(buf)) | ||
|
|
||
| /** | ||
| * Create a new [[MysqlBufReader]] from an array of bytes. | ||
| */ | ||
| def apply(bytes: Array[Byte]): MysqlBufReader = | ||
| apply(Buf.ByteArray.Owned(bytes)) | ||
| } |
Oops, something went wrong.