Struct ReadBuffer 

pub struct ReadBuffer { /* private fields */ }

A buffer for reading TNS protocol data

Implementations

impl ReadBuffer

pub fn new(data: Bytes) -> Self

Create a new ReadBuffer from bytes

pub fn from_slice(data: &[u8]) -> Self

Create a new ReadBuffer from a byte slice

pub fn from_vec(data: Vec<u8>) -> Self

Create a new ReadBuffer from a Vec

pub fn position(&self) -> usize

Get the current position in the buffer

pub fn len(&self) -> usize

Get the total length of the buffer

pub fn is_empty(&self) -> bool

Check if the buffer is empty

pub fn remaining(&self) -> usize

Get the number of bytes remaining to be read

pub fn remaining_bytes(&self) -> &[u8]

Get a slice of the remaining bytes (without advancing position)

pub fn has_remaining(&self, n: usize) -> bool

Check if there are at least n bytes remaining

pub fn skip(&mut self, n: usize) -> Result<()>

Skip n bytes in the buffer

pub fn skip_raw_bytes_chunked(&mut self) -> Result<()>

Skip raw bytes that may be chunked

This is used for skipping variable-length data in Oracle’s TTC protocol. The first byte gives the length. If the length is TNS_LONG_LENGTH_INDICATOR (254), then chunks are read and discarded until a chunk with length 0 is found.

pub fn read_raw_bytes_chunked(&mut self) -> Result<Vec<u8>>

Read raw bytes that may be chunked

This is used for reading variable-length data in Oracle’s TTC protocol. The first byte gives the length. If the length is TNS_LONG_LENGTH_INDICATOR (254), then chunks are read and concatenated until a chunk with length 0 is found.

pub fn reset(&mut self)

Reset the buffer position to the beginning

pub fn set_position(&mut self, pos: usize) -> Result<()>

Set the buffer position

pub fn remaining_slice(&self) -> &[u8]

Get a slice of the remaining data

pub fn as_bytes(&self) -> &Bytes

Get the underlying bytes

pub fn read_u8(&mut self) -> Result<u8>

Read a single byte

pub fn read_bytes(&mut self, buf: &mut [u8]) -> Result<()>

Read raw bytes into a slice

pub fn read_bytes_owned(&mut self, n: usize) -> Result<Bytes>

Read raw bytes and return as a new Bytes

pub fn read_bytes_vec(&mut self, n: usize) -> Result<Vec<u8>>

Read raw bytes and return as a Vec

pub fn read_u16_be(&mut self) -> Result<u16>

Read a 16-bit unsigned integer in big-endian format

pub fn read_i16_be(&mut self) -> Result<i16>

Read a 16-bit signed integer in big-endian format

pub fn read_u16_le(&mut self) -> Result<u16>

Read a 16-bit unsigned integer in little-endian format

pub fn read_u32_be(&mut self) -> Result<u32>

Read a 32-bit unsigned integer in big-endian format

pub fn read_u64_be(&mut self) -> Result<u64>

Read a 64-bit unsigned integer in big-endian format

pub fn read_ub1(&mut self) -> Result<u8>

Read a TNS UB1 (unsigned byte)

pub fn read_ub2(&mut self) -> Result<u16>

Read a TNS UB2 (unsigned 2-byte, variable length encoded)

TNS UB2 uses a length-prefixed encoding where:

• First byte is the length (0, 1, or 2)
• If length is 0: value is 0
• If length is 1: read 1 byte
• If length is 2: read 2 bytes as big-endian u16

pub fn read_sb2(&mut self) -> Result<i16>

Read a TNS SB2 (signed 2-byte, variable length encoded)

Same encoding as UB2 but returns signed i16

pub fn read_ub4(&mut self) -> Result<u32>

Read a TNS UB4 (unsigned 4-byte, variable length encoded)

TNS UB4 uses a length-prefixed encoding where:

• First byte is the length (0, 1, 2, 3, or 4)
• If length is 0: value is 0
• If length is 1: read 1 byte
• If length is 2: read 2 bytes as big-endian u16
• If length is 3: read 3 bytes
• If length is 4: read 4 bytes as big-endian u32

pub fn read_ub8(&mut self) -> Result<u64>

Read a TNS UB8 (unsigned 8-byte, variable length encoded)

TNS UB8 uses a length-prefixed encoding where:

• First byte is the length (0-8)
• Read that many bytes and interpret as big-endian integer

pub fn read_bytes_with_length(&mut self) -> Result<Option<Vec<u8>>>

Read a TNS length-prefixed byte sequence

Returns None if the length indicator is NULL_INDICATOR (255). For data > 252 bytes, uses chunked decoding:

• Read LONG_INDICATOR (254)
• Read chunks: ub4(chunk_len) + raw bytes, until chunk_len is 0

pub fn read_string_with_length(&mut self) -> Result<Option<String>>

Read a TNS length-prefixed string (UTF-8)

pub fn read_string_with_ub4_length(&mut self) -> Result<Option<String>>

Read a string with UB4 outer length prefix (used for metadata strings)

This is the format used by Oracle for column names, schema names, etc. The format is:

1. UB4 (length-prefixed u32) giving the byte count as an indicator
2. If > 0, a TNS length-prefixed byte sequence (another length prefix + data)

Python’s read_str_with_length uses this format.

pub fn read_oracle_int(&mut self) -> Result<i64>

Read a fixed-size Oracle integer (used in various places)

Oracle encodes integers with a length prefix indicating the number of bytes. The actual bytes follow in big-endian order.

pub fn read_oracle_uint(&mut self) -> Result<u64>

Read an Oracle unsigned integer

pub fn skip_ub1(&mut self) -> Result<()>

Skip a UB1

pub fn skip_ub2(&mut self) -> Result<()>

Skip a UB2 (length-prefixed 2-byte integer)

Format: first byte is length (0-2), followed by that many bytes

pub fn skip_ub4(&mut self) -> Result<()>

Skip a UB4 (length-prefixed 4-byte integer)

Format: first byte is length (0-4), followed by that many bytes

pub fn skip_ub8(&mut self) -> Result<()>

Skip a UB8 (length-prefixed 8-byte integer)

Format: first byte is length (0-8), followed by that many bytes

pub fn peek_u8(&self) -> Result<u8>

Peek at the next byte without consuming it

pub fn peek_bytes(&self, n: usize) -> Result<&[u8]>

Peek at the next n bytes without consuming them

Trait Implementations

impl Debug for ReadBuffer

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&[u8]> for ReadBuffer

fn from(data: &[u8]) -> Self

Converts to this type from the input type.

impl From<Bytes> for ReadBuffer

fn from(data: Bytes) -> Self

Converts to this type from the input type.

impl From<Vec<u8>> for ReadBuffer

fn from(data: Vec<u8>) -> Self

Converts to this type from the input type.