Rename to Decoder.

Implement BufDecoder.
Added methods to get stream_len and stream_position.

src/lib.rs

@@ -1,35 +1,135 @@
-use std::fs::File;
-use std::io::Read;
-use std::path::Path;
+pub mod read {
+    use std::fs::File;
+    use std::io::{Read, Seek, SeekFrom};
+    use std::path::Path;
 
-use bzip2::read::BzDecoder;
-use flate2::read::GzDecoder;
+    use bzip2::read::BzDecoder;
+    use flate2::read::GzDecoder;
 
-pub enum FileDecompressed {
+    pub enum Decoder {
         Raw(File),
         Gz(GzDecoder<File>),
         Bz(BzDecoder<File>),
-}
-
-impl Read for FileDecompressed {
-    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
-        match self {
-            FileDecompressed::Raw(file) => file.read(buf),
-            FileDecompressed::Gz(file) => file.read(buf),
-            FileDecompressed::Bz(file) => file.read(buf),
     }
-    }
-}
 
-pub fn open<P>(path: P) -> Result<FileDecompressed, std::io::Error>
-where
+    impl Decoder {
+        pub fn open<P>(path: P) -> Result<Decoder, std::io::Error>
+        where
             P: AsRef<Path>,
-{
+        {
             let file = File::open(&path)?;
 
             Ok(match mime_guess::from_path(path).first_raw() {
-        Some("application/x-gzip") => FileDecompressed::Gz(GzDecoder::new(file)),
-        Some("application/x-bzip2") => FileDecompressed::Bz(BzDecoder::new(file)),
-        _ => FileDecompressed::Raw(file),
+                Some("application/x-gzip") => Decoder::Gz(GzDecoder::new(file)),
+                Some("application/x-bzip2") => Decoder::Bz(BzDecoder::new(file)),
+                _ => Decoder::Raw(file),
             })
+        }
+
+        pub fn stream_len(&mut self) -> std::io::Result<u64> {
+            let file = match self {
+                Decoder::Raw(file) => file,
+                Decoder::Gz(file) => file.get_mut(),
+                Decoder::Bz(file) => file.get_mut(),
+            };
+
+            let old_pos = file.seek(SeekFrom::Current(0))?;
+            let len = file.seek(SeekFrom::End(0))?;
+
+            if old_pos != len {
+                file.seek(SeekFrom::Start(old_pos))?;
+            }
+
+            Ok(len)
+        }
+
+        pub fn stream_position(&mut self) -> std::io::Result<u64> {
+            let file = match self {
+                Decoder::Raw(file) => file,
+                Decoder::Gz(file) => file.get_mut(),
+                Decoder::Bz(file) => file.get_mut(),
+            };
+
+            file.seek(SeekFrom::Current(0))
+        }
+    }
+
+    impl Read for Decoder {
+        #[inline]
+        fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+            match self {
+                Decoder::Raw(file) => file.read(buf),
+                Decoder::Gz(file) => file.read(buf),
+                Decoder::Bz(file) => file.read(buf),
+            }
+        }
+    }
+}
+
+pub mod bufread {
+    use std::fs::File;
+    use std::io::{BufReader, Read, Seek, SeekFrom};
+    use std::path::Path;
+
+    use bzip2::bufread::BzDecoder;
+    use flate2::bufread::GzDecoder;
+
+    pub enum BufDecoder {
+        Raw(BufReader<File>),
+        Gz(GzDecoder<BufReader<File>>),
+        Bz(BzDecoder<BufReader<File>>),
+    }
+
+    impl BufDecoder {
+        pub fn open<P>(path: P) -> Result<BufDecoder, std::io::Error>
+        where
+            P: AsRef<Path>,
+        {
+            let file = File::open(&path).map(BufReader::new)?;
+
+            Ok(match mime_guess::from_path(path).first_raw() {
+                Some("application/x-gzip") => BufDecoder::Gz(GzDecoder::new(file)),
+                Some("application/x-bzip2") => BufDecoder::Bz(BzDecoder::new(file)),
+                _ => BufDecoder::Raw(file),
+            })
+        }
+
+        pub fn stream_len(&mut self) -> std::io::Result<u64> {
+            let file = match self {
+                BufDecoder::Raw(file) => file,
+                BufDecoder::Gz(file) => file.get_mut(),
+                BufDecoder::Bz(file) => file.get_mut(),
+            };
+
+            let old_pos = file.seek(SeekFrom::Current(0))?;
+            let len = file.seek(SeekFrom::End(0))?;
+
+            if old_pos != len {
+                file.seek(SeekFrom::Start(old_pos))?;
+            }
+
+            Ok(len)
+        }
+
+        pub fn stream_position(&mut self) -> std::io::Result<u64> {
+            let file = match self {
+                BufDecoder::Raw(file) => file,
+                BufDecoder::Gz(file) => file.get_mut(),
+                BufDecoder::Bz(file) => file.get_mut(),
+            };
+
+            file.seek(SeekFrom::Current(0))
+        }
+    }
+
+    impl Read for BufDecoder {
+        #[inline]
+        fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+            match self {
+                BufDecoder::Raw(file) => file.read(buf),
+                BufDecoder::Gz(file) => file.read(buf),
+                BufDecoder::Bz(file) => file.read(buf),
+            }
+        }
+    }
 }