Misc: Add debug logging via log crate

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
       `read_properties`, specified with a `bool` in `read_from{_path}`. This will now default to `true`,
       and can be overridden when using `Probe`.
 - **FileProperties**: `FileProperties::new`
+- Debug logging via the [log](crates.io/crates/log) crate for exposing recoverable errors.
 
 ### Changed
 - **ID3v2**: Frame/tag flags with optional additional data are now `Option<T>` instead of `(bool, T)`

Cargo.toml

@@ -19,7 +19,10 @@ byteorder = "1.4.3"
 cfg-if = "1.0.0"
 # ID3 compressed frames
 flate2 = { version = "1.0.24", optional = true }
+# Proc macros
 lofty_attr = { path = "lofty_attr" }
+# Debug logging
+log = "0.4.17"
 # OGG Vorbis/Opus
 ogg_pager = "0.3.2"
 # Key maps

src/ape/tag/read.rs

@@ -48,8 +48,8 @@ where
 		let read_only = (flags & 1) == 1;
 		let item_type = (flags >> 1) & 3;
 
-		// TODO: This could use a warning
 		if value_size == 0 || key.len() < 2 || key.len() > 255 {
+			log::debug!("APE: Encountered invalid item key ({})", key);
 			continue;
 		}
 

src/mpeg/header.rs

@@ -1,7 +1,6 @@
 use super::constants::{BITRATES, PADDING_SIZES, SAMPLES, SAMPLE_RATES, SIDE_INFORMATION_SIZES};
 use crate::error::Result;
-use crate::macros::{decode_err, parse_mode_choice};
-use crate::probe::ParsingMode;
+use crate::macros::decode_err;
 
 use std::io::{Read, Seek, SeekFrom};
 
@@ -190,12 +189,12 @@ pub(crate) struct Header {
 }
 
 impl Header {
-	pub(super) fn read(data: u32, parse_mode: ParsingMode) -> Result<Option<Self>> {
+	pub(super) fn read(data: u32) -> Option<Self> {
 		let version = match (data >> 19) & 0b11 {
 			0 => MpegVersion::V2_5,
 			2 => MpegVersion::V2,
 			3 => MpegVersion::V1,
-			_ => return Ok(None),
+			_ => return None,
 		};
 
 		let version_index = if version == MpegVersion::V1 { 0 } else { 1 };
@@ -205,11 +204,8 @@ impl Header {
 			2 => Layer::Layer2,
 			3 => Layer::Layer1,
 			_ => {
-				parse_mode_choice!(
-					parse_mode,
-					STRICT: decode_err!(@BAIL MPEG, "Frame header uses a reserved layer"),
-					RELAXED: return Ok(None)
-				);
+				log::debug!("MPEG: Frame header uses a reserved layer");
+				return None;
 			},
 		};
 
@@ -233,14 +229,14 @@ impl Header {
 		let bitrate_index = (data >> 12) & 0xF;
 		header.bitrate = BITRATES[version_index][layer_index][bitrate_index as usize];
 		if header.bitrate == 0 {
-			return Ok(None);
+			return None;
 		}
 
 		// Sample rate index
 		let sample_rate_index = (data >> 10) & 0b11;
 		header.sample_rate = match sample_rate_index {
 			// This is invalid
-			3 => return Ok(None),
+			3 => return None,
 			_ => SAMPLE_RATES[header.version as usize][sample_rate_index as usize],
 		};
 
@@ -281,7 +277,7 @@ impl Header {
 		header.len =
 			(u32::from(header.samples) * header.bitrate * 125 / header.sample_rate) + padding;
 
-		Ok(Some(header))
+		Some(header)
 	}
 }
 
@@ -291,7 +287,7 @@ pub(super) struct XingHeader {
 }
 
 impl XingHeader {
-	pub(super) fn read(reader: &mut &[u8], parse_mode: ParsingMode) -> Result<Option<Self>> {
+	pub(super) fn read(reader: &mut &[u8]) -> Result<Option<Self>> {
 		let reader_len = reader.len();
 
 		let mut header = [0; 4];
@@ -307,11 +303,10 @@ impl XingHeader {
 				reader.read_exact(&mut flags)?;
 
 				if flags[3] & 0x03 != 0x03 {
-					parse_mode_choice!(
-						parse_mode,
-						STRICT: decode_err!(@BAIL MPEG, "Xing header doesn't have required flags set (0x0001 and 0x0002)"),
-						RELAXED: return Ok(None)
+					log::debug!(
+						"MPEG: Xing header doesn't have required flags set (0x0001 and 0x0002)"
 					);
+					return Ok(None);
 				}
 
 				let frames = reader.read_u32::<BigEndian>()?;