LibAudio: Use the proper functions to read WAV samples

Turns out that, if we don't use functions that ensure reading until the
very end of the buffer, we only end up getting the very beginning of
samples and fill the rest with uninitialized data.

While at it, make sure that we read the data that is little endian as a
LittleEndian.

Userland/Libraries/LibAudio/WavLoader.cpp

@@ -75,13 +75,9 @@ MaybeLoaderError WavLoaderPlugin::read_samples_from_stream(Stream& stream, Sampl
 // There's no i24 type + we need to do the endianness conversion manually anyways.
 static ErrorOr<double> read_sample_int24(Stream& stream)
 {
-    u8 byte = 0;
-    TRY(stream.read(Bytes { &byte, 1 }));
-    i32 sample1 = byte;
-    TRY(stream.read(Bytes { &byte, 1 }));
-    i32 sample2 = byte;
-    TRY(stream.read(Bytes { &byte, 1 }));
-    i32 sample3 = byte;
+    i32 sample1 = TRY(stream.read_value<u8>());
+    i32 sample2 = TRY(stream.read_value<u8>());
+    i32 sample3 = TRY(stream.read_value<u8>());
 
     i32 value = 0;
     value = sample1;
@@ -97,7 +93,7 @@ template<typename T>
 static ErrorOr<double> read_sample(Stream& stream)
 {
     T sample { 0 };
-    TRY(stream.read(Bytes { &sample, sizeof(T) }));
+    TRY(stream.read_entire_buffer(Bytes { &sample, sizeof(T) }));
     // Remap integer samples to normalized floating-point range of -1 to 1.
     if constexpr (IsIntegral<T>) {
         if constexpr (NumericLimits<T>::is_signed()) {
@@ -163,7 +159,7 @@ LoaderSamples WavLoaderPlugin::get_more_samples(size_t max_samples_to_read_from_
         pcm_bits_per_sample(m_sample_format), sample_format_name(m_sample_format));
 
     auto sample_data = LOADER_TRY(ByteBuffer::create_zeroed(bytes_to_read));
-    LOADER_TRY(m_stream->read(sample_data.bytes()));
+    LOADER_TRY(m_stream->read_entire_buffer(sample_data.bytes()));
 
     // m_loaded_samples should contain the amount of actually loaded samples
     m_loaded_samples += samples_to_read;
@@ -191,22 +187,19 @@ MaybeLoaderError WavLoaderPlugin::parse_header()
     size_t bytes_read = 0;
 
     auto read_u8 = [&]() -> ErrorOr<u8, LoaderError> {
-        u8 value;
-        LOADER_TRY(m_stream->read(Bytes { &value, 1 }));
+        u8 value = LOADER_TRY(m_stream->read_value<LittleEndian<u8>>());
         bytes_read += 1;
         return value;
     };
 
     auto read_u16 = [&]() -> ErrorOr<u16, LoaderError> {
-        u16 value;
-        LOADER_TRY(m_stream->read(Bytes { &value, 2 }));
+        u16 value = LOADER_TRY(m_stream->read_value<LittleEndian<u16>>());
         bytes_read += 2;
         return value;
     };
 
     auto read_u32 = [&]() -> ErrorOr<u32, LoaderError> {
-        u32 value;
-        LOADER_TRY(m_stream->read(Bytes { &value, 4 }));
+        u32 value = LOADER_TRY(m_stream->read_value<LittleEndian<u32>>());
         bytes_read += 4;
         return value;
     };