Buffer PHP

Buffer for PHP strings (ByteArray)

Prerequisites

• PHP 8.0+
• GMP extension enabled

Installation

composer require comely-io/buffer-php

Buffer

Constructors

Method	Description
fromBase16	Initialize buffer using Base16/Hexadecimal encoded string
fromBase64	Initialize buffer from Base64 encoded string
fromByteArray	Initialize buffer from byte array
fromBinary	Initialize buffer from array of binary encoded bytes
__construct	Creates a new buffer instance from given argument

Fixed-length Buffers

Methods

Method	Description
len	Get length/size of buffer in bytes
raw	Get existing bytes in buffer as string
byteArray	Returns an indexed Array comprised of every byte's position on ASCII table
copy	Creates a copy of buffer from given start and/or up to length
equals	Compares buffer bytes with another buffer or string
read	Creates a ByteReader instance
hash	Creates a ByteDigest instance
switchEndianess	Converts endianess of entire buffer between big and little endians
dump	Buffer information as an Array
applyFn	Applies a function/callback to existing buffer creating a new buffer instance as result
toBase16	Encodes the buffer as Base16/Hexadecimal
toBase64	Encodes the buffer in Base64
toBinary	Encodes the buffer into an indexed Array where each index is binary representation of byte (1s and 0s)
checkSize	Checks if buffer is comprised of exactly same number of bytes as in argument, throws LengthException otherwise

Writeable Buffers

All the methods from fixed-length buffers above, and also:

Methods

Method	Description
clean	Flush any existing data in buffer
readOnly	Puts buffer in Read-only state; Nothing further can be appended to it
writable	Puts buffer in writable state
isWritable	Return boolean
append	Append bytes to end of buffer
prepend	Prepend bytes to start of buffer
prependUInt8	Prepends a single byte integer
appendUInt8	Appends a single byte integer
appendUInt16LE	Appends 2 byte integer in little endian byte order
appendUInt16BE	Appends 2 byte integer in big endian byte order
appendUInt32LE	Appends 4 byte integer in little endian byte order
appendUInt32BE	Appends 4 byte integer in big endian byte order
appendUInt64LE	Appends 8 byte integer in little endian byte order
appendUInt64BE	Appends 8 byte integer in big endian byte order

ByteReader

For systematically reading bytes from buffer in order. Useful for serialization and un-serialization of data (i.e. Bitcoin blocks and transactions)

Methods

Method	Description
ignoreUnderflow	If invoked, ByteReaderUnderflowException will not be thrown if required number of bytes are not present
isEnd	return boolean if end of buffer has been reached
len	Length of buffer in bytes
pos	Current position/index at byte in buffer
reset	Resets position index to 0
first	Resets position index to 0, then reads N number of bytes from start of buffer
lookBehind	Reads last N bytes previously read (does NOT update internal pointer)
lookAhead	Reads next N bytes but does NOT updates internal pointer
next	Reads next N bytes while updating the pointer
readUInt8	Reads and converts next 1 byte as UInt8
readUInt16LE	Reads and converts next 2 bytes as UInt16 from little endian byte order
readUInt16BE	Reads and converts next 2 bytes as UInt16 from big endian byte order
readUInt32LE	Reads and converts next 4 bytes as UInt32 from little endian byte order
readUInt32BE	Reads and converts next 4 bytes as UInt32 from big endian byte order
readUInt64LE	Reads and converts next 8 bytes as UInt64 from little endian byte order
readUInt64BE	Reads and converts next 8 bytes as UInt64 from big endian byte order
setPointer	Sets internal reading pointer to specified byte
remaining	Retrieved all remaining bytes in buffer (does NOT update internal pointer)

ByteDigest

Applies hash function to bytes in buffer and returns digest bytes.

Check PHP.net hash_algos() and hash_hmac_algos() for list of available/supported algorithms.

Methods

Method	Description
toString	If invoked before any other method, all hash functions will return string instead of new buffer instance
hash	Applies specified hash algorithm times N iterations and returns X numbers of bytes from digest
hmac	Applies HMAC hash function
pbkdf2	Applies PBKDF2 hash function
md5	Applies md5 hash function
sha1	Applies SHA1 hash function
sha256	Applies SHA256 hash function
sha512	Applies SHA512 hash function
ripeMd160	Applies ripeMd160 hash function