Merge pull request #146 from chyvonomys/optional-decoders

Optional decoders

Cargo.toml

@@ -9,9 +9,16 @@ repository = "https://github.com/tomaka/rodio"
 documentation = "http://docs.rs/rodio"
 
 [dependencies]
-claxon = "0.3.0"
+claxon = { version = "0.3.0", optional = true }
 cpal = "0.5.1"
-hound = "1.0.0"
+hound = { version = "1.0.0", optional = true }
 lazy_static = "0.1.12"
-lewton = "0.5"
+lewton = { version = "0.5", optional = true }
 cgmath = "0.14"
+
+[features]
+default = ["flac", "vorbis", "wav"]
+
+flac = ["claxon"]
+vorbis = ["lewton"]
+wav = ["hound"]

src/decoder/mod.rs

@@ -7,20 +7,31 @@ use std::time::Duration;
 
 use Source;
 
+#[cfg(feature = "flac")]
 mod flac;
+#[cfg(feature = "vorbis")]
 mod vorbis;
+#[cfg(feature = "wav")]
 mod wav;
 
 /// Source of audio samples from decoding a file.
 ///
 /// Supports WAV, Vorbis and Flac.
+#[cfg(any(feature = "wav", feature = "flac", feature = "vorbis"))]
 pub struct Decoder<R>(DecoderImpl<R>) where R: Read + Seek;
 
+#[cfg(not(any(feature = "wav", feature = "flac", feature = "vorbis")))]
+pub struct Decoder<R>(::std::marker::PhantomData<R>);
+
+#[cfg(any(feature = "wav", feature = "flac", feature = "vorbis"))]
 enum DecoderImpl<R>
     where R: Read + Seek
 {
+    #[cfg(feature = "wav")]
     Wav(wav::WavDecoder<R>),
+    #[cfg(feature = "vorbis")]
     Vorbis(vorbis::VorbisDecoder<R>),
+    #[cfg(feature = "flac")]
     Flac(flac::FlacDecoder<R>),
 }
 
@@ -30,7 +41,9 @@ impl<R> Decoder<R>
     /// Builds a new decoder.
     ///
     /// Attempts to automatically detect the format of the source of data.
+    #[allow(unused_variables)]
     pub fn new(data: R) -> Result<Decoder<R>, DecoderError> {
+        #[cfg(feature = "wav")]
         let data = match wav::WavDecoder::new(data) {
             Err(data) => data,
             Ok(decoder) => {
@@ -38,6 +51,7 @@ impl<R> Decoder<R>
             },
         };
 
+        #[cfg(feature = "flac")]
         let data = match flac::FlacDecoder::new(data) {
             Err(data) => data,
             Ok(decoder) => {
@@ -45,14 +59,28 @@ impl<R> Decoder<R>
             },
         };
 
-        if let Ok(decoder) = vorbis::VorbisDecoder::new(data) {
-            return Ok(Decoder(DecoderImpl::Vorbis(decoder)));
-        }
+        #[cfg(feature = "vorbis")]
+        let data = match vorbis::VorbisDecoder::new(data) {
+            Err(data) => data,
+            Ok(decoder) => {
+                return Ok(Decoder(DecoderImpl::Vorbis(decoder)));
+            },
+        };
 
         Err(DecoderError::UnrecognizedFormat)
     }
 }
 
+#[cfg(not(any(feature = "wav", feature = "flac", feature = "vorbis")))]
+impl<R> Iterator for Decoder<R>
+    where R: Read + Seek
+{
+    type Item = i16;
+
+    fn next(&mut self) -> Option<i16> { None }
+}
+
+#[cfg(any(feature = "wav", feature = "flac", feature = "vorbis"))]
 impl<R> Iterator for Decoder<R>
     where R: Read + Seek
 {
@@ -61,8 +89,11 @@ impl<R> Iterator for Decoder<R>
     #[inline]
     fn next(&mut self) -> Option<i16> {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref mut source) => source.next(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref mut source) => source.next(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref mut source) => source.next(),
         }
     }
@@ -70,21 +101,38 @@ impl<R> Iterator for Decoder<R>
     #[inline]
     fn size_hint(&self) -> (usize, Option<usize>) {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref source) => source.size_hint(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref source) => source.size_hint(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref source) => source.size_hint(),
         }
     }
 }
 
+#[cfg(not(any(feature = "wav", feature = "flac", feature = "vorbis")))]
+impl<R> Source for Decoder<R>
+    where R: Read + Seek
+{
+    fn current_frame_len(&self) -> Option<usize> { Some(0) }
+    fn channels(&self) -> u16 { 0 }
+    fn samples_rate(&self) -> u32 { 1 }
+    fn total_duration(&self) -> Option<Duration> { Some(Duration::default()) }
+}
+
+#[cfg(any(feature = "wav", feature = "flac", feature = "vorbis"))]
 impl<R> Source for Decoder<R>
     where R: Read + Seek
 {
     #[inline]
     fn current_frame_len(&self) -> Option<usize> {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref source) => source.current_frame_len(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref source) => source.current_frame_len(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref source) => source.current_frame_len(),
         }
     }
@@ -92,8 +140,11 @@ impl<R> Source for Decoder<R>
     #[inline]
     fn channels(&self) -> u16 {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref source) => source.channels(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref source) => source.channels(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref source) => source.channels(),
         }
     }
@@ -101,8 +152,11 @@ impl<R> Source for Decoder<R>
     #[inline]
     fn samples_rate(&self) -> u32 {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref source) => source.samples_rate(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref source) => source.samples_rate(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref source) => source.samples_rate(),
         }
     }
@@ -110,8 +164,11 @@ impl<R> Source for Decoder<R>
     #[inline]
     fn total_duration(&self) -> Option<Duration> {
         match self.0 {
+            #[cfg(feature = "wav")]
             DecoderImpl::Wav(ref source) => source.total_duration(),
+            #[cfg(feature = "vorbis")]
             DecoderImpl::Vorbis(ref source) => source.total_duration(),
+            #[cfg(feature = "flac")]
             DecoderImpl::Flac(ref source) => source.total_duration(),
         }
     }

src/lib.rs

@@ -83,11 +83,14 @@
 
 #![cfg_attr(test, deny(missing_docs))]
 
+#[cfg(feature = "flac")]
 extern crate claxon;
 extern crate cpal;
+#[cfg(feature = "wav")]
 extern crate hound;
 #[macro_use]
 extern crate lazy_static;
+#[cfg(feature = "vorbis")]
 extern crate lewton;
 extern crate cgmath;