oml_audio/
fileloader.rs

1use std::fs::{ File, OpenOptions };
2use std::io::{BufReader,SeekFrom};
3use std::io::prelude::*;
4
5
6pub trait FileLoaderFile {
7	fn is_valid( &self ) -> bool;
8	fn read_u8( &mut self ) -> u8;
9	fn eof( &self ) -> bool;
10	fn name( &self ) -> &str;
11
12	fn read_u16( &mut self ) -> u16 {
13		let a = self.read_u8() as u16;
14		let b = self.read_u8() as u16;
15
16		  ( b << 8 )
17		| ( a << 0 )
18	}
19
20	fn read_u32( &mut self ) -> u32 {
21		let a = self.read_u8() as u32;
22		let b = self.read_u8() as u32;
23		let c = self.read_u8() as u32;
24		let d = self.read_u8() as u32;
25
26		  ( d << 24 )
27		| ( c << 16 )
28		| ( b <<  8 )
29		| ( a <<  0 )
30	}
31}
32
33
34pub trait FileLoader {
35	fn open( &mut self, filename: &str ) -> Box< dyn FileLoaderFile >;
36	fn exists( &self, filename: &str ) -> bool;
37}
38
39
40pub struct FileLoaderFileDisk {
41	filename: String,	// only needed for better debugging
42	file: Option< BufReader< File > >,
43	size: usize,
44	pos: usize,
45}
46
47impl FileLoaderFileDisk {
48	pub fn open( filename: &str ) -> Self {
49		let mut s = Self {
50			filename: filename.to_string(),
51			file: None,
52			size: 0,
53			pos: 0,
54		};
55
56		if let Ok( mut f ) = File::open( &s.filename ) {
57			if let Ok( p ) =  f.seek(SeekFrom::End(0)) {
58				f.seek( SeekFrom::Start( 0 ) ).unwrap();
59				s.size = p as usize
60			} else {
61			}
62			let f = BufReader::new(f);
63
64			s.file = Some( f );
65		};
66
67		s
68	}
69}
70
71impl FileLoaderFile for FileLoaderFileDisk {
72	fn read_u8( &mut self ) -> u8 {
73
74		match &mut self.file {
75			Some( f ) => {
76				let mut buf = [0];
77				match f.read( &mut buf ) {
78					Ok( _ ) => {
79						self.pos += 1;
80						buf[ 0 ]
81					},
82					Err( _ ) => 0,
83				}
84
85			},
86			None => {
87				0
88			},
89		}
90
91	}
92	fn is_valid( &self ) -> bool {
93		self.file.is_some()
94	}
95	fn eof( &self ) -> bool {
96		self.pos >= self.size
97	}
98	fn name( &self ) -> &str {
99		&self.filename
100	}	
101}
102
103pub struct FileLoaderDisk {
104	basedir:	String,
105	debug:		bool,
106}
107
108impl FileLoaderDisk {
109	pub fn new( basedir: &str ) -> Self {
110		Self {
111			basedir: 	basedir.to_string(),
112			debug:		false,
113		}
114	}
115	pub fn enable_debug ( &mut self ) {
116		self.debug = true;
117	}
118}
119
120impl FileLoader for FileLoaderDisk {
121	fn open( &mut self, filename: &str ) -> Box< dyn FileLoaderFile > {
122		let fullname = format!("{}/{}", &self.basedir, &filename);
123		if self.debug { println!("FileLoaderDisk opening {}", fullname); }
124		let stream = FileLoaderFileDisk::open( &fullname );
125
126		Box::new( stream )
127	}
128	fn exists( &self, filename: &str ) -> bool {
129		let fullname = format!("{}/{}", &self.basedir, &filename);
130		if self.debug { println!("FileLoaderDisk exists? {}", fullname); }
131		std::path::Path::new(&fullname).exists()
132	}
133
134
135}
oml_audio/fileloader.rs

oml_audio/
fileloader.rs
