+//! Bytestream reading/writing functionality.
pub use std::io::SeekFrom;
use std::fs::File;
use std::io::prelude::*;
use std::ptr;
+/// A list specifying general bytestream reading and writing errors.
#[derive(Debug)]
pub enum ByteIOError {
+ /// End of stream.
EOF,
+ /// Wrong seek position was provided.
WrongRange,
+ /// Tried to call read() on bytestream writer or write() on bytestream reader.
WrongIOMode,
+ /// Functionality is not implemented.
NotImplemented,
+ /// Read error.
ReadError,
+ /// Write error.
WriteError,
+ /// Seeking failed.
SeekError,
}
+/// A specialised `Result` type for bytestream operations.
pub type ByteIOResult<T> = Result<T, ByteIOError>;
+/// Common trait for bytestream operations.
pub trait ByteIO {
+ /// Reads data into provided buffer. Fails if it cannot fill whole buffer.
fn read_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize>;
+ /// Reads data into provided buffer. Partial read is treated as success.
fn read_buf_some(&mut self, buf: &mut [u8]) -> ByteIOResult<usize>;
+ /// Reads data into provided buffer but does not advance read position.
fn peek_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize>;
+ /// Reads single byte from the stream.
fn read_byte(&mut self) -> ByteIOResult<u8>;
+ /// Returns the next byte value in the stream without advancing read position.
fn peek_byte(&mut self) -> ByteIOResult<u8>;
+ /// Writes buffer to the stream.
fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()>;
+ /// Returns current read or write position.
fn tell(&mut self) -> u64;
+ /// Seeks to the provided position.
fn seek(&mut self, pos: SeekFrom) -> ByteIOResult<u64>;
+ /// Tells whether this is end of stream.
fn is_eof(&self) -> bool;
+ /// Reports whether stream is seekable or not.
fn is_seekable(&mut self) -> bool;
+ /// Returns stream size or -1 if it is not known.
fn size(&mut self) -> i64;
}
+/// High-level bytestream reader.
+///
+/// User is supposed to create some reader implementing [`ByteIO`] trait e.g. [`MemoryReader`] and use it to create `ByteReader` which can be used for reading e.g. various integer types.
+///
+/// # Examples
+///
+/// ````
+/// use nihav_core::io::byteio::{MemoryReader,ByteReader};
+/// # use nihav_core::io::byteio::ByteIOResult;
+///
+/// # fn foo() -> ByteIOResult<()> {
+/// let memory: [u8; 4] = [ 0, 42, 42, 0 ];
+/// let mut mr = MemoryReader::new_read(&memory);
+/// let mut br = ByteReader::new(&mut mr);
+/// let val = br.read_u16be()?; // read 16-bit big-endian integer, should be 42
+/// let val = br.read_u16le()?; // read 16-bit little-endian integer, should be 42 as well
+/// # Ok(())
+/// # }
+/// ````
+///
+/// [`ByteIO`]: ./trait.ByteIO.html
+/// [`MemoryReader`]: ./struct.MemoryReader.html
#[allow(dead_code)]
pub struct ByteReader<'a> {
io: &'a mut ByteIO,
}
+/// Bytestream reader from memory.
pub struct MemoryReader<'a> {
buf: &'a [u8],
pos: usize,
}
+/// Bytestream reader from file.
pub struct FileReader<'a> {
file: &'a File,
eof: bool,
macro_rules! read_int_func {
($s: ident, $inttype: ty, $size: expr, $which: ident) => {
+/// Reads integer of certain size and endianness.
pub fn $s(src: &[u8]) -> ByteIOResult<$inttype> {
if src.len() < $size { return Err(ByteIOError::ReadError); }
unsafe {
read_int_func!(read_u64be, u64, 8, to_be);
read_int_func!(read_u64le, u64, 8, to_le);
+/// Reads 24-bit big-endian integer.
+///
+/// # Example
+///
+/// ````
+/// use nihav_core::io::byteio::read_u24be;
+/// # use nihav_core::io::byteio::ByteIOResult;
+///
+/// # fn foo() -> ByteIOResult<()> {
+/// let src: [u8; 3] = [ 1, 2, 3];
+/// let value = read_u24be(&src)?; // should return 0x010203
+/// # Ok(())
+/// # }
+/// ````
pub fn read_u24be(src: &[u8]) -> ByteIOResult<u32> {
if src.len() < 3 { return Err(ByteIOError::ReadError); }
Ok((u32::from(src[0]) << 16) | (u32::from(src[1]) << 8) | u32::from(src[2]))
}
+/// Reads 24-bit little-endian integer.
pub fn read_u24le(src: &[u8]) -> ByteIOResult<u32> {
if src.len() < 3 { return Err(ByteIOError::ReadError); }
Ok((u32::from(src[2]) << 16) | (u32::from(src[1]) << 8) | u32::from(src[0]))
}
+/// Reads 32-bit big-endian floating point number.
pub fn read_f32be(src: &[u8]) -> ByteIOResult<f32> { Ok(f32::from_bits(read_u32be(src)?)) }
+/// Reads 32-bit little-endian floating point number.
pub fn read_f32le(src: &[u8]) -> ByteIOResult<f32> { Ok(f32::from_bits(read_u32le(src)?)) }
+/// Reads 64-bit big-endian floating point number.
pub fn read_f64be(src: &[u8]) -> ByteIOResult<f64> { Ok(f64::from_bits(read_u64be(src)?)) }
+/// Reads 64-bit little-endian floating point number.
pub fn read_f64le(src: &[u8]) -> ByteIOResult<f64> { Ok(f64::from_bits(read_u64le(src)?)) }
macro_rules! write_int_func {
($s: ident, $inttype: ty, $size: expr, $which: ident) => {
+/// Writes integer of certain size and endianness into byte buffer.
pub fn $s(dst: &mut [u8], val: $inttype) -> ByteIOResult<()> {
if dst.len() < $size { return Err(ByteIOError::WriteError); }
unsafe {
write_int_func!(write_u64be, u64, 8, to_be);
write_int_func!(write_u64le, u64, 8, to_le);
+/// Writes 24-bit big-endian integer to the provided buffer.
+///
+/// # Example
+///
+/// ````
+/// use nihav_core::io::byteio::write_u24be;
+/// # use nihav_core::io::byteio::ByteIOResult;
+///
+/// # fn foo() -> ByteIOResult<()> {
+/// let mut dst = [0u8; 3];
+/// write_u24be(&mut dst, 0x010203)?;
+/// // dst should contain [ 1, 2, 3] now
+/// # Ok(())
+/// # }
+/// ````
pub fn write_u24be(dst: &mut [u8], val: u32) -> ByteIOResult<()> {
if dst.len() < 3 { return Err(ByteIOError::WriteError); }
dst[0] = (val >> 16) as u8;
dst[2] = (val >> 0) as u8;
Ok(())
}
+/// Writes 24-bit little-endian integer to the provided buffer.
pub fn write_u24le(dst: &mut [u8], val: u32) -> ByteIOResult<()> {
if dst.len() < 3 { return Err(ByteIOError::WriteError); }
dst[0] = (val >> 0) as u8;
dst[2] = (val >> 16) as u8;
Ok(())
}
+/// Writes 32-bit big-endian floating point number to the provided buffer.
pub fn write_f32be(dst: &mut [u8], val: f32) -> ByteIOResult<()> { write_u32be(dst, val.to_bits()) }
+/// Writes 32-bit little-endian floating point number to the provided buffer.
pub fn write_f32le(dst: &mut [u8], val: f32) -> ByteIOResult<()> { write_u32le(dst, val.to_bits()) }
+/// Writes 64-bit big-endian floating point number to the provided buffer.
pub fn write_f64be(dst: &mut [u8], val: f64) -> ByteIOResult<()> { write_u64be(dst, val.to_bits()) }
+/// Writes 64-bit little-endian floating point number to the provided buffer.
pub fn write_f64le(dst: &mut [u8], val: f64) -> ByteIOResult<()> { write_u64le(dst, val.to_bits()) }
impl<'a> ByteReader<'a> {
+ /// Constructs a new instance of bytestream reader.
+ ///
+ /// # Examples
+ ///
+ /// ````
+ /// use nihav_core::io::byteio::{MemoryReader,ByteReader};
+ /// # use nihav_core::io::byteio::ByteIOResult;
+ ///
+ /// # fn foo() -> ByteIOResult<()> {
+ /// let memory: [u8; 4] = [ 0, 42, 42, 0 ];
+ /// let mut mr = MemoryReader::new_read(&memory);
+ /// let mut br = ByteReader::new(&mut mr);
+ /// # Ok(())
+ /// # }
+ /// ````
pub fn new(io: &'a mut ByteIO) -> Self { ByteReader { io } }
+ /// Reads data into provided buffer. Partial read is treated as success.
pub fn read_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
self.io.read_buf(buf)
}
+ /// Reads data into provided buffer. Partial read is treated as success.
pub fn read_buf_some(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
self.io.read_buf_some(buf)
}
+ /// Reads data into provided buffer but does not advance read position.
pub fn peek_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
self.io.peek_buf(buf)
}
+ /// Reads single byte from the stream.
pub fn read_byte(&mut self) -> ByteIOResult<u8> {
self.io.read_byte()
}
+ /// Returns the next byte value in the stream without advancing read position.
pub fn peek_byte(&mut self) -> ByteIOResult<u8> {
self.io.peek_byte()
}
+ /// Reads 16-bit big-endian integer from the stream.
pub fn read_u16be(&mut self) -> ByteIOResult<u16> {
read_int!(self, u16, 2, to_be)
}
+ /// Reads 16-bit big-endian integer from the stream without advancing read position.
pub fn peek_u16be(&mut self) -> ByteIOResult<u16> {
peek_int!(self, u16, 2, to_be)
}
+ /// Reads 24-bit big-endian integer from the stream.
pub fn read_u24be(&mut self) -> ByteIOResult<u32> {
let p16 = self.read_u16be()?;
let p8 = self.read_byte()?;
Ok((u32::from(p16) << 8) | u32::from(p8))
}
+ /// Reads 24-bit big-endian integer from the stream without advancing read position.
pub fn peek_u24be(&mut self) -> ByteIOResult<u32> {
let mut src: [u8; 3] = [0; 3];
self.peek_buf(&mut src)?;
Ok((u32::from(src[0]) << 16) | (u32::from(src[1]) << 8) | u32::from(src[2]))
}
+ /// Reads 32-bit big-endian integer from the stream.
pub fn read_u32be(&mut self) -> ByteIOResult<u32> {
read_int!(self, u32, 4, to_be)
}
+ /// Reads 32-bit big-endian integer from the stream without advancing read position.
pub fn peek_u32be(&mut self) -> ByteIOResult<u32> {
peek_int!(self, u32, 4, to_be)
}
+ /// Reads 64-bit big-endian integer from the stream.
pub fn read_u64be(&mut self) -> ByteIOResult<u64> {
read_int!(self, u64, 8, to_be)
}
+ /// Reads 64-bit big-endian integer from the stream without advancing read position.
pub fn peek_u64be(&mut self) -> ByteIOResult<u64> {
peek_int!(self, u64, 8, to_be)
}
+ /// Reads 32-bit big-endian floating point number from the stream.
pub fn read_f32be(&mut self) -> ByteIOResult<f32> {
Ok(f32::from_bits(self.read_u32be()?))
}
+ /// Reads 32-bit big-endian floating point number from the stream without advancing read position.
pub fn peek_f32be(&mut self) -> ByteIOResult<f32> {
Ok(f32::from_bits(self.peek_u32be()?))
}
+ /// Reads 64-bit big-endian floating point number from the stream.
pub fn read_f64be(&mut self) -> ByteIOResult<f64> {
Ok(f64::from_bits(self.read_u64be()?))
}
+ /// Reads 64-bit big-endian floating point number from the stream without advancing read position.
pub fn peek_f64be(&mut self) -> ByteIOResult<f64> {
Ok(f64::from_bits(self.peek_u64be()?))
}
+ /// Reads 16-bit little-endian integer from the stream.
pub fn read_u16le(&mut self) -> ByteIOResult<u16> {
read_int!(self, u16, 2, to_le)
}
+ /// Reads 16-bit little-endian integer from the stream without advancing read position.
pub fn peek_u16le(&mut self) -> ByteIOResult<u16> {
peek_int!(self, u16, 2, to_le)
}
+ /// Reads 24-bit little-endian integer from the stream.
pub fn read_u24le(&mut self) -> ByteIOResult<u32> {
let p8 = self.read_byte()?;
let p16 = self.read_u16le()?;
Ok((u32::from(p16) << 8) | u32::from(p8))
}
+ /// Reads 24-bit little-endian integer from the stream without advancing read position.
pub fn peek_u24le(&mut self) -> ByteIOResult<u32> {
let mut src: [u8; 3] = [0; 3];
self.peek_buf(&mut src)?;
Ok(u32::from(src[0]) | (u32::from(src[1]) << 8) | (u32::from(src[2]) << 16))
}
+ /// Reads 32-bit little-endian integer from the stream.
pub fn read_u32le(&mut self) -> ByteIOResult<u32> {
read_int!(self, u32, 4, to_le)
}
+ /// Reads 32-bit little-endian integer from the stream without advancing read position.
pub fn peek_u32le(&mut self) -> ByteIOResult<u32> {
peek_int!(self, u32, 4, to_le)
}
+ /// Reads 64-bit little-endian integer from the stream.
pub fn read_u64le(&mut self) -> ByteIOResult<u64> {
read_int!(self, u64, 8, to_le)
}
+ /// Reads 64-bit little-endian integer from the stream without advancing read position.
pub fn peek_u64le(&mut self) -> ByteIOResult<u64> {
peek_int!(self, u64, 8, to_le)
}
+ /// Reads 32-bit little-endian floating point number from the stream.
pub fn read_f32le(&mut self) -> ByteIOResult<f32> {
Ok(f32::from_bits(self.read_u32le()?))
}
+ /// Reads 32-bit little-endian floating point number from the stream without advancing read position.
pub fn peek_f32le(&mut self) -> ByteIOResult<f32> {
Ok(f32::from_bits(self.peek_u32le()?))
}
+ /// Reads 64-bit little-endian floating point number from the stream.
pub fn read_f64le(&mut self) -> ByteIOResult<f64> {
Ok(f64::from_bits(self.read_u64le()?))
}
+ /// Reads 64-bit little-endian floating point number from the stream without advancing read position.
pub fn peek_f64le(&mut self) -> ByteIOResult<f64> {
Ok(f64::from_bits(self.peek_u64le()?))
}
+ /// Skips requested number of bytes.
pub fn read_skip(&mut self, len: usize) -> ByteIOResult<()> {
if self.io.is_seekable() {
self.io.seek(SeekFrom::Current(len as i64))?;
Ok(())
}
+ /// Returns current read position.
pub fn tell(&mut self) -> u64 {
self.io.tell()
}
+ /// Seeks to the provided position.
pub fn seek(&mut self, pos: SeekFrom) -> ByteIOResult<u64> {
self.io.seek(pos)
}
+ /// Tells whether this is end of stream.
pub fn is_eof(&self) -> bool {
self.io.is_eof()
}
+ /// Returns stream size or -1 if it is not known.
pub fn size(&mut self) -> i64 {
self.io.size()
}
+ /// Reports number of bytes left in the stream.
pub fn left(&mut self) -> i64 {
let size = self.io.size();
if size == -1 { return -1; }
}
impl<'a> MemoryReader<'a> {
-
+ /// Constructs a new instance of `MemoryReader`.
pub fn new_read(buf: &'a [u8]) -> Self {
MemoryReader { buf, pos: 0 }
}
impl<'a> FileReader<'a> {
+ /// Constructs a new instance of `FileReader`.
pub fn new_read(file: &'a mut File) -> Self {
FileReader { file, eof : false }
}
}
}
+/// High-level bytestream writer.
+///
+/// User is supposed to create some writer implementing [`ByteIO`] trait e.g. [`MemoryWriter`] and use it to create `ByteWriter` which can be used for writing e.g. various integer types.
+///
+/// # Examples
+///
+/// ````
+/// use nihav_core::io::byteio::{MemoryWriter,ByteWriter};
+/// # use nihav_core::io::byteio::ByteIOResult;
+///
+/// # fn foo() -> ByteIOResult<()> {
+/// let mut memory = [0u8; 4];
+/// let mut mw = MemoryWriter::new_write(&mut memory);
+/// let mut bw = ByteWriter::new(&mut mw);
+/// let val = bw.write_u16be(42)?; // memory should be [ 0, 42, 0, 0 ]
+/// let val = bw.write_u16le(42)?; // memory should be [ 0, 42, 42, 0 ]
+/// # Ok(())
+/// # }
+/// ````
+///
+/// [`ByteIO`]: ./trait.ByteIO.html
+/// [`MemoryWriter`]: ./struct.MemoryWriter.html
#[allow(dead_code)]
pub struct ByteWriter<'a> {
io: &'a mut ByteIO,
}
+/// Bytestream writer to memory.
pub struct MemoryWriter<'a> {
buf: &'a mut [u8],
pos: usize,
}
+/// Bytestream writer to file.
pub struct FileWriter {
file: File,
}
impl<'a> ByteWriter<'a> {
+ /// Constructs a new instance of `ByteWriter`.
pub fn new(io: &'a mut ByteIO) -> Self { ByteWriter { io } }
+ /// Writes byte array to the output.
pub fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()> {
self.io.write_buf(buf)
}
+ /// Writes single byte to the output.
pub fn write_byte(&mut self, val: u8) -> ByteIOResult<()> {
let buf: [u8; 1] = [val];
self.io.write_buf(&buf)
}
+ /// Writes 16-bit big-endian integer to the output.
pub fn write_u16be(&mut self, val: u16) -> ByteIOResult<()> {
let buf: [u8; 2] = [((val >> 8) & 0xFF) as u8, (val & 0xFF) as u8];
self.io.write_buf(&buf)
}
+ /// Writes 16-bit little-endian integer to the output.
pub fn write_u16le(&mut self, val: u16) -> ByteIOResult<()> {
let buf: [u8; 2] = [(val & 0xFF) as u8, ((val >> 8) & 0xFF) as u8];
self.io.write_buf(&buf)
}
+ /// Writes 24-bit big-endian integer to the output.
pub fn write_u24be(&mut self, val: u32) -> ByteIOResult<()> {
let buf: [u8; 3] = [((val >> 16) & 0xFF) as u8, ((val >> 8) & 0xFF) as u8, (val & 0xFF) as u8];
self.write_buf(&buf)
}
+ /// Writes 24-bit little-endian integer to the output.
pub fn write_u24le(&mut self, val: u32) -> ByteIOResult<()> {
let buf: [u8; 3] = [(val & 0xFF) as u8, ((val >> 8) & 0xFF) as u8, ((val >> 16) & 0xFF) as u8];
self.write_buf(&buf)
}
+ /// Writes 32-bit big-endian integer to the output.
pub fn write_u32be(&mut self, val: u32) -> ByteIOResult<()> {
self.write_u16be(((val >> 16) & 0xFFFF) as u16)?;
self.write_u16be((val & 0xFFFF) as u16)
}
+ /// Writes 32-bit little-endian integer to the output.
pub fn write_u32le(&mut self, val: u32) -> ByteIOResult<()> {
self.write_u16le((val & 0xFFFF) as u16)?;
self.write_u16le(((val >> 16) & 0xFFFF) as u16)
}
+ /// Writes 64-bit big-endian integer to the output.
pub fn write_u64be(&mut self, val: u64) -> ByteIOResult<()> {
self.write_u32be((val >> 32) as u32)?;
self.write_u32be(val as u32)
}
+ /// Writes 64-bit little-endian integer to the output.
pub fn write_u64le(&mut self, val: u64) -> ByteIOResult<()> {
self.write_u32le(val as u32)?;
self.write_u32le((val >> 32) as u32)
}
+ /// Writes 32-bit big-endian floating point number to the output.
pub fn write_f32be(&mut self, val: f32) -> ByteIOResult<()> {
self.write_u32be(val.to_bits())
}
+ /// Writes 32-bit little-endian floating point number to the output.
pub fn write_f32le(&mut self, val: f32) -> ByteIOResult<()> {
self.write_u32le(val.to_bits())
}
+ /// Writes 64-bit big-endian floating point number to the output.
pub fn write_f64be(&mut self, val: f64) -> ByteIOResult<()> {
self.write_u64be(val.to_bits())
}
+ /// Writes 64-bit little-endian floating point number to the output.
pub fn write_f64le(&mut self, val: f64) -> ByteIOResult<()> {
self.write_u64le(val.to_bits())
}
+ /// Reports the current write position.
pub fn tell(&mut self) -> u64 {
self.io.tell()
}
+ /// Seeks to the requested position.
pub fn seek(&mut self, pos: SeekFrom) -> ByteIOResult<u64> {
self.io.seek(pos)
}
+ /// Reports the amount of bytes the writer can still write (-1 if unknown).
pub fn size_left(&mut self) -> i64 {
let sz = self.io.size();
if sz == -1 { return -1; }
impl<'a> MemoryWriter<'a> {
+ /// Constructs a new instance of `MemoryWriter`.
pub fn new_write(buf: &'a mut [u8]) -> Self {
MemoryWriter { buf, pos: 0 }
}
}
impl FileWriter {
+ /// Constructs a new instance of `FileWriter`.
pub fn new_write(file: File) -> Self {
FileWriter { file }
}
projects / nihav.git / commitdiff