//! Bytestream reading/writing functionality.
pub use std::io::SeekFrom;
-use std::fs::File;
use std::io::prelude::*;
use std::ptr;
fn is_seekable(&mut self) -> bool;
/// Returns stream size or -1 if it is not known.
fn size(&mut self) -> i64;
+ /// Flushes output if possible.
+ fn flush(&mut self) -> ByteIOResult<()>;
}
/// High-level bytestream reader.
/// [`MemoryReader`]: ./struct.MemoryReader.html
#[allow(dead_code)]
pub struct ByteReader<'a> {
- io: &'a mut ByteIO,
+ io: &'a mut dyn ByteIO,
}
/// Bytestream reader from memory.
pos: usize,
}
-/// Bytestream reader from file.
-pub struct FileReader<'a> {
- file: &'a File,
+/// Bytestream reader from anything implementing `std::io::Read` and `std::io::Seek`.
+pub struct FileReader<T: Read+Seek> {
+ file: Box<T>,
+ eof: bool,
+}
+
+/// Bytestream reader from anything implementing `std::io::Read` and `std::io::Seek` that operates only on a part of the input.
+pub struct BoundedFileReader<T: Read+Seek> {
+ file: Box<T>,
+ start: u64,
+ end: Option<u64>,
eof: bool,
}
/// # Ok(())
/// # }
/// ````
+#[allow(clippy::identity_op)]
pub fn write_u24be(dst: &mut [u8], val: u32) -> ByteIOResult<()> {
if dst.len() < 3 { return Err(ByteIOError::WriteError); }
dst[0] = (val >> 16) as u8;
Ok(())
}
/// Writes 24-bit little-endian integer to the provided buffer.
+#[allow(clippy::identity_op)]
pub fn write_u24le(dst: &mut [u8], val: u32) -> ByteIOResult<()> {
if dst.len() < 3 { return Err(ByteIOError::WriteError); }
dst[0] = (val >> 0) as u8;
/// # Ok(())
/// # }
/// ````
- pub fn new(io: &'a mut ByteIO) -> Self { ByteReader { io } }
+ pub fn new(io: &'a mut dyn 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> {
fn size(&mut self) -> i64 {
self.buf.len() as i64
}
+
+ fn flush(&mut self) -> ByteIOResult<()> { Ok(()) }
}
-impl<'a> FileReader<'a> {
+impl<T: Read+Seek> FileReader<T> {
/// Constructs a new instance of `FileReader`.
- pub fn new_read(file: &'a mut File) -> Self {
+ pub fn new_read(file: T) -> Self {
+ FileReader { file: Box::new(file), eof : false }
+ }
+ /// Constructs a new instance of `FileReader` using a boxed resource.
+ pub fn new_read_boxed(file: Box<T>) -> Self {
FileReader { file, eof : false }
}
+ /// Destroys the reader and releases the reader resource for a further use.
+ pub fn finish(self) -> Box<T> { self.file }
}
-impl<'a> ByteIO for FileReader<'a> {
+impl<T: Read+Seek> ByteIO for FileReader<T> {
fn read_byte(&mut self) -> ByteIOResult<u8> {
let mut byte : [u8; 1] = [0];
let ret = self.file.read(&mut byte);
}
fn read_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
- let ret = self.file.read(buf);
- if ret.is_err() { return Err(ByteIOError::ReadError); }
- let sz = ret.unwrap();
- if sz < buf.len() { self.eof = true; return Err(ByteIOError::EOF); }
- Ok(sz)
+ match self.file.read_exact(buf) {
+ Ok(()) => Ok(buf.len()),
+ Err(err) => {
+ if err.kind() == std::io::ErrorKind::UnexpectedEof {
+ self.eof = true;
+ Err(ByteIOError::EOF)
+ } else {
+ Err(ByteIOError::ReadError)
+ }
+ },
+ }
}
fn read_buf_some(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
let ret = self.file.read(buf);
if ret.is_err() { return Err(ByteIOError::ReadError); }
let sz = ret.unwrap();
- if sz < buf.len() { self.eof = true; }
+ if sz < buf.len() {
+ if let Err(_err) = self.file.read(&mut buf[sz..][..1]) {
+ self.eof = true;
+ } else {
+ return Ok(sz + 1);
+ }
+ }
Ok(sz)
}
fn size(&mut self) -> i64 {
-1
}
+
+ fn flush(&mut self) -> ByteIOResult<()> { Ok(()) }
+}
+
+
+impl<T: Read+Seek> BoundedFileReader<T> {
+
+ /// Constructs a new instance of `BoundedFileReader`. The reader pretends that data before `start` and after `end` (if set) does not exist.
+ pub fn new_read(file: T, start: u64, end: Option<u64>) -> ByteIOResult<Self> {
+ let mut file = Box::new(file);
+ if let Some(epos) = end {
+ if start > epos {
+ return Err(ByteIOError::WrongRange);
+ }
+ }
+ if start > 0 && file.seek(SeekFrom::Start(start)).is_err() {
+ return Err(ByteIOError::SeekError);
+ }
+ Ok(Self { file, start, end, eof : false })
+ }
+ /// Constructs a new instance of `BoundedFileReader` using a boxed resource. The reader pretends that data before `start` and after `end` (if set) does not exist.
+ pub fn new_read_boxed(mut file: Box<T>, start: u64, end: Option<u64>) -> ByteIOResult<Self> {
+ if let Some(epos) = end {
+ if start > epos {
+ return Err(ByteIOError::WrongRange);
+ }
+ }
+ if start > 0 && file.seek(SeekFrom::Start(start)).is_err() {
+ return Err(ByteIOError::SeekError);
+ }
+ Ok(Self { file, start, end, eof : false })
+ }
+ /// Destroys the reader and releases the reader resource for a further use.
+ pub fn finish(self) -> Box<T> { self.file }
+ fn real_tell(&mut self) -> u64 {
+ self.file.seek(SeekFrom::Current(0)).unwrap()
+ }
+ fn max_read_len(&mut self, len: usize) -> usize {
+ if let Some(epos) = self.end {
+ (len as u64).min(epos - self.real_tell()) as usize
+ } else {
+ len
+ }
+ }
+}
+
+impl<T: Read+Seek> ByteIO for BoundedFileReader<T> {
+ fn read_byte(&mut self) -> ByteIOResult<u8> {
+ if let Some(epos) = self.end {
+ if self.real_tell() >= epos {
+ self.eof = true;
+ return Err(ByteIOError::EOF);
+ }
+ }
+ let mut byte : [u8; 1] = [0];
+ let ret = self.file.read(&mut byte);
+ if ret.is_err() { return Err(ByteIOError::ReadError); }
+ let sz = ret.unwrap();
+ if sz == 0 { self.eof = true; return Err(ByteIOError::EOF); }
+ Ok (byte[0])
+ }
+
+ fn peek_byte(&mut self) -> ByteIOResult<u8> {
+ let b = self.read_byte()?;
+ if self.file.seek(SeekFrom::Current(-1)).is_err() {
+ return Err(ByteIOError::SeekError);
+ }
+ Ok(b)
+ }
+
+ fn read_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ let len = self.max_read_len(buf.len());
+ match self.file.read_exact(&mut buf[..len]) {
+ Ok(()) if len == buf.len() => Ok(buf.len()),
+ Ok(()) => {
+ self.eof = true;
+ Err(ByteIOError::EOF)
+ },
+ Err(err) => {
+ if err.kind() == std::io::ErrorKind::UnexpectedEof {
+ self.eof = true;
+ Err(ByteIOError::EOF)
+ } else {
+ Err(ByteIOError::ReadError)
+ }
+ },
+ }
+ }
+
+ fn read_buf_some(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ let len = self.max_read_len(buf.len());
+ let ret = self.file.read(&mut buf[..len]);
+ if ret.is_err() { return Err(ByteIOError::ReadError); }
+ let sz = ret.unwrap();
+ if sz < len {
+ if let Err(_err) = self.file.read(&mut buf[sz..][..1]) {
+ self.eof = true;
+ } else {
+ return Ok(sz + 1);
+ }
+ }
+ Ok(sz)
+ }
+
+ fn peek_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ let len = self.max_read_len(buf.len());
+ let size = self.read_buf(&mut buf[..len])?;
+ if self.file.seek(SeekFrom::Current(-(size as i64))).is_err() {
+ return Err(ByteIOError::SeekError);
+ }
+ Ok(size)
+ }
+
+ #[allow(unused_variables)]
+ fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ fn tell(&mut self) -> u64 {
+ self.file.seek(SeekFrom::Current(0)).unwrap() - self.start
+ }
+
+ fn seek(&mut self, pos: SeekFrom) -> ByteIOResult<u64> {
+ let res = match pos {
+ SeekFrom::Start(off) => {
+ let dpos = self.start + off;
+ if let Some(epos) = self.end {
+ if dpos > epos {
+ return Err(ByteIOError::WrongRange);
+ }
+ }
+ self.file.seek(SeekFrom::Start(dpos))
+ },
+ SeekFrom::Current(off) => {
+ let dpos = (self.real_tell() as i64) + off;
+ let end = self.end.unwrap_or(dpos as u64);
+ if dpos < 0 || ((dpos as u64) < self.start) || ((dpos as u64) > end) {
+ return Err(ByteIOError::WrongRange);
+ }
+ self.file.seek(pos)
+ },
+ SeekFrom::End(off) => {
+ if let Some(epos) = self.end {
+ let dpos = (epos as i64) + off;
+ if dpos < (self.start as i64) || ((dpos as u64) > epos) {
+ return Err(ByteIOError::WrongRange);
+ }
+ self.file.seek(SeekFrom::Start(dpos as u64))
+ } else {
+ self.file.seek(pos)
+ }
+ },
+ };
+ match res {
+ Ok(r) => Ok(r),
+ Err(_) => Err(ByteIOError::SeekError),
+ }
+ }
+
+ fn is_eof(&self) -> bool {
+ self.eof
+ }
+
+ fn is_seekable(&mut self) -> bool {
+ true
+ }
+
+ fn size(&mut self) -> i64 {
+ -1
+ }
+
+ fn flush(&mut self) -> ByteIOResult<()> { Ok(()) }
}
+
/// 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.
/// [`MemoryWriter`]: ./struct.MemoryWriter.html
#[allow(dead_code)]
pub struct ByteWriter<'a> {
- io: &'a mut ByteIO,
+ io: &'a mut dyn ByteIO,
}
/// Bytestream writer to memory.
pos: usize,
}
-/// Bytestream writer to file.
-pub struct FileWriter {
- file: File,
+/// Bytestream writer to anything implementing `std::io::Write` and `std::io::Seek`.
+pub struct FileWriter<T: Write+Seek> {
+ file: Box<T>,
+}
+
+/// Bytestream writer to memory.
+///
+/// Unlike [`MemoryWriter`] which writes to an array of fixed size, `GrowableMemoryWriter` grows output size when output size exceeds capacity.
+///
+/// [`MemoryWriter`]: ./struct.MemoryWriter.html
+pub struct GrowableMemoryWriter<'a> {
+ buf: &'a mut Vec<u8>,
+ pos: usize,
}
impl<'a> ByteWriter<'a> {
/// Constructs a new instance of `ByteWriter`.
- pub fn new(io: &'a mut ByteIO) -> Self { ByteWriter { io } }
+ pub fn new(io: &'a mut dyn ByteIO) -> Self { ByteWriter { io } }
/// Writes byte array to the output.
pub fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()> {
if sz == -1 { return -1; }
sz - (self.tell() as i64)
}
+
+ /// Flushes output stream if possible.
+ pub fn flush(&mut self) -> ByteIOResult<()> {
+ self.io.flush()
+ }
}
impl<'a> MemoryWriter<'a> {
fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()> {
if self.pos + buf.len() > self.buf.len() { return Err(ByteIOError::WriteError); }
- for i in 0..buf.len() {
- self.buf[self.pos + i] = buf[i];
+ self.buf[self.pos..][..buf.len()].copy_from_slice(buf);
+ self.pos += buf.len();
+ Ok(())
+ }
+
+ fn tell(&mut self) -> u64 {
+ self.pos as u64
+ }
+
+ fn seek(&mut self, pos: SeekFrom) -> ByteIOResult<u64> {
+ let cur_pos = self.pos as i64;
+ let cur_size = self.buf.len() as i64;
+ match pos {
+ SeekFrom::Start(x) => self.real_seek(x as i64),
+ SeekFrom::Current(x) => self.real_seek(cur_pos + x),
+ SeekFrom::End(x) => self.real_seek(cur_size + x),
}
+ }
+
+ fn is_eof(&self) -> bool {
+ self.pos >= self.buf.len()
+ }
+
+ fn is_seekable(&mut self) -> bool {
+ true
+ }
+
+ fn size(&mut self) -> i64 {
+ self.buf.len() as i64
+ }
+
+ fn flush(&mut self) -> ByteIOResult<()> { Ok(()) }
+}
+
+impl<'a> GrowableMemoryWriter<'a> {
+
+ /// Constructs a new instance of `GrowableMemoryWriter`.
+ pub fn new_write(buf: &'a mut Vec<u8>) -> Self {
+ GrowableMemoryWriter { buf, pos: 0 }
+ }
+
+ fn real_seek(&mut self, pos: i64) -> ByteIOResult<u64> {
+ if pos < 0 || (pos as usize) > self.buf.len() {
+ return Err(ByteIOError::WrongRange)
+ }
+ self.pos = pos as usize;
+ Ok(pos as u64)
+ }
+}
+
+impl<'a> ByteIO for GrowableMemoryWriter<'a> {
+ #[allow(unused_variables)]
+ fn read_byte(&mut self) -> ByteIOResult<u8> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ #[allow(unused_variables)]
+ fn peek_byte(&mut self) -> ByteIOResult<u8> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ #[allow(unused_variables)]
+ fn read_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ #[allow(unused_variables)]
+ fn read_buf_some(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ #[allow(unused_variables)]
+ fn peek_buf(&mut self, buf: &mut [u8]) -> ByteIOResult<usize> {
+ Err(ByteIOError::NotImplemented)
+ }
+
+ fn write_buf(&mut self, buf: &[u8]) -> ByteIOResult<()> {
+ if self.pos + buf.len() > self.buf.len() {
+ self.buf.resize(self.pos + buf.len(), 0);
+ }
+ self.buf[self.pos..][..buf.len()].copy_from_slice(buf);
self.pos += buf.len();
Ok(())
}
fn size(&mut self) -> i64 {
self.buf.len() as i64
}
+
+ fn flush(&mut self) -> ByteIOResult<()> { Ok(()) }
}
-impl FileWriter {
+impl<T: Write+Seek> FileWriter<T> {
/// Constructs a new instance of `FileWriter`.
- pub fn new_write(file: File) -> Self {
- FileWriter { file }
+ pub fn new_write(file: T) -> Self {
+ FileWriter { file: Box::new(file) }
}
}
-impl ByteIO for FileWriter {
+impl<T: Write+Seek> ByteIO for FileWriter<T> {
#[allow(unused_variables)]
fn read_byte(&mut self) -> ByteIOResult<u8> {
Err(ByteIOError::NotImplemented)
fn size(&mut self) -> i64 {
-1
}
+
+ fn flush(&mut self) -> ByteIOResult<()> {
+ match self.file.flush() {
+ Ok(()) => Ok(()),
+ Err(_) => Err(ByteIOError::WriteError),
+ }
+ }
}
#[cfg(test)]
projects / nihav.git / blobdiff