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use std::fs; use std::fs::File; use std::path::Path; use std::io::{Error, ErrorKind, Read, Seek, SeekFrom}; use buffer::Buffer; use reader::Reader; #[derive(Debug)] pub struct FileReader { pub filename: String, pub position: u64, pub file: Option<File>, pub buffer: Buffer, } pub fn exists(filename: &str) -> bool { Path::new(filename).exists() } impl Reader for FileReader { fn new() -> FileReader { FileReader { filename: "".to_string(), position: 0, file: None, buffer: Buffer { size: None, position: 0, max_end_position: None, buffer: vec![], }, } } fn open(&mut self, filename: &str) -> Result<(), String> { self.filename = filename.to_string(); match File::open(filename) { Err(msg) => Err(msg.to_string()), Ok(file) => { self.file = Some(file); Ok(()) } } } fn get_position(&mut self) -> Result<u64, String> { Ok(self.position) } fn get_cache_size(&self) -> Option<usize> { self.buffer.size } fn set_cache_size(&mut self, cache_size: Option<usize>) { self.buffer.size = cache_size; } fn get_max_end_position(&self) -> Option<u64> { self.buffer.max_end_position } fn set_max_end_position(&mut self, max_end_position: Option<u64>) { self.buffer.max_end_position = max_end_position; } fn get_size(&mut self) -> Result<u64, String> { let metadata = try!(fs::metadata(self.filename.clone()).map_err(|e| e.to_string())); Ok(metadata.len()) } } impl Read for FileReader { fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error> { if let Some(ref mut file_reader) = self.file { let readed_size = file_reader.read(buf)?; self.position += readed_size as u64; Ok(readed_size) } else { Err(Error::new(ErrorKind::Other, "No file opened")) } } } impl Seek for FileReader { fn seek(&mut self, seek_from: SeekFrom) -> Result<u64, Error> { if let Some(ref mut file_reader) = self.file { file_reader.seek(seek_from) } else { Err(Error::new(ErrorKind::Other, "No file opened")) } } }