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use std::fs; use std::path::Path; use std::fs::File; use std::io::prelude::*; use std::io::Read; use std::io::SeekFrom; use reader::Reader; use buffer::Buffer; #[derive(Debug)] pub struct FileReader { pub filename: String, pub position: u64, pub file: File, pub buffer: Buffer } pub fn exists(filename: &String) -> bool { Path::new(&filename).exists() } impl Reader for FileReader { fn open(filename: &String) -> FileReader { match File::open(filename) { Err(msg) => panic!(msg.to_string()), Ok(file) => FileReader { filename: filename.to_string(), position: 0, file: file, buffer: Buffer { size: None, position: 0, max_end_position: None, buffer: vec![] } }, } } 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()) } fn read(&mut self, size: usize) -> Result<Vec<u8>, String> { let mut data = vec![0; size]; let loaded_size = try!(self.file.read(&mut data).map_err(|e| e.to_string())); match loaded_size == size { true => { self.position = self.position + size as u64; Ok(data) }, false => Ok(Vec::new()), } } fn seek(&mut self, seek: SeekFrom) -> Result<u64, String> { let position = try!(self.file.seek(seek).map_err(|e| e.to_string())); self.position = position; Ok(position) } }