ParseOptions: Add ParseOptions::read_tags

CHANGELOG.md

@@ -6,6 +6,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+- **ParseOptions**: `ParseOptions::read_tags` to skip the parsing of tags ([issue](https://github.com/Serial-ATA/lofty-rs/issues/251)) ([PR](https://github.com/Serial-ATA/lofty-rs/pull/406))
+
 ## [0.20.1] - 2024-07-02
 
 ### Fixed

lofty/src/aac/read.rs

@@ -48,18 +48,20 @@ where
 
 				stream_len -= u64::from(header.size);
 
-				let id3v2 = parse_id3v2(reader, header, parse_mode)?;
-				if let Some(existing_tag) = &mut file.id3v2_tag {
-					log::warn!("Duplicate ID3v2 tag found, appending frames to previous tag");
-
-					// https://github.com/Serial-ATA/lofty-rs/issues/87
-					// Duplicate tags should have their frames appended to the previous
-					for frame in id3v2.frames {
-						existing_tag.insert(frame);
+				if parse_options.read_tags {
+					let id3v2 = parse_id3v2(reader, header, parse_mode)?;
+					if let Some(existing_tag) = &mut file.id3v2_tag {
+						log::warn!("Duplicate ID3v2 tag found, appending frames to previous tag");
+
+						// https://github.com/Serial-ATA/lofty-rs/issues/87
+						// Duplicate tags should have their frames appended to the previous
+						for frame in id3v2.frames {
+							existing_tag.insert(frame);
+						}
+						continue;
 					}
-					continue;
+					file.id3v2_tag = Some(id3v2);
 				}
-				file.id3v2_tag = Some(id3v2);
 
 				// Skip over the footer
 				if skip_footer {
@@ -94,7 +96,7 @@ where
 	}
 
 	#[allow(unused_variables)]
-	let ID3FindResults(header, id3v1) = find_id3v1(reader, true)?;
+	let ID3FindResults(header, id3v1) = find_id3v1(reader, parse_options.read_tags)?;
 
 	if header.is_some() {
 		stream_len -= 128;

lofty/src/ape/read.rs

@@ -8,7 +8,7 @@ use crate::id3::v1::tag::Id3v1Tag;
 use crate::id3::v2::read::parse_id3v2;
 use crate::id3::v2::tag::Id3v2Tag;
 use crate::id3::{find_id3v1, find_id3v2, find_lyrics3v2, FindId3v2Config, ID3FindResults};
-use crate::macros::decode_err;
+use crate::macros::{decode_err, err};
 
 use std::io::{Read, Seek, SeekFrom};
 
@@ -27,10 +27,14 @@ where
 	let mut id3v1_tag: Option<Id3v1Tag> = None;
 	let mut ape_tag: Option<ApeTag> = None;
 
+	let find_id3v2_config = if parse_options.read_tags {
+		FindId3v2Config::READ_TAG
+	} else {
+		FindId3v2Config::NO_READ_TAG
+	};
+
 	// ID3v2 tags are unsupported in APE files, but still possible
-	if let ID3FindResults(Some(header), Some(content)) =
-		find_id3v2(data, FindId3v2Config::READ_TAG)?
-	{
+	if let ID3FindResults(Some(header), content) = find_id3v2(data, find_id3v2_config)? {
 		log::warn!("Encountered an ID3v2 tag. This tag cannot be rewritten to the APE file!");
 
 		stream_len -= u64::from(header.size);
@@ -40,10 +44,12 @@ where
 			stream_len -= 10;
 		}
 
-		let reader = &mut &*content;
+		if let Some(content) = content {
+			let reader = &mut &*content;
 
-		let id3v2 = parse_id3v2(reader, header, parse_options.parsing_mode)?;
-		id3v2_tag = Some(id3v2);
+			let id3v2 = parse_id3v2(reader, header, parse_options.parsing_mode)?;
+			id3v2_tag = Some(id3v2);
+		}
 	}
 
 	let mut found_mac = false;
@@ -76,14 +82,16 @@ where
 				})?;
 
 				if &remaining[..4] != b"AGEX" {
-					decode_err!(@BAIL Ape, "Found incomplete APE tag");
+					err!(FakeTag)
 				}
 
 				let ape_header = read_ape_header(data, false)?;
 				stream_len -= u64::from(ape_header.size);
 
-				let ape = read_ape_tag_with_header(data, ape_header)?;
-				ape_tag = Some(ape);
+				if parse_options.read_tags {
+					let ape = read_ape_tag_with_header(data, ape_header)?;
+					ape_tag = Some(ape);
+				}
 			},
 			_ => {
 				decode_err!(@BAIL Ape, "Invalid data found while reading header, expected any of [\"MAC \", \"APETAGEX\", \"ID3\"]")
@@ -96,7 +104,7 @@ where
 	// Starts with ['T', 'A', 'G']
 	// Exactly 128 bytes long (including the identifier)
 	#[allow(unused_variables)]
-	let ID3FindResults(id3v1_header, id3v1) = find_id3v1(data, true)?;
+	let ID3FindResults(id3v1_header, id3v1) = find_id3v1(data, parse_options.read_tags)?;
 
 	if id3v1_header.is_some() {
 		stream_len -= 128;
@@ -117,9 +125,9 @@ where
 	// Strongly recommended to be at the end of the file
 	data.seek(SeekFrom::Current(-32))?;
 
-	if let Some((tag, header)) = read_ape_tag(data, true)? {
+	if let (tag, Some(header)) = read_ape_tag(data, true, parse_options.read_tags)? {
 		stream_len -= u64::from(header.size);
-		ape_tag = Some(tag);
+		ape_tag = tag;
 	}
 
 	let file_length = data.stream_position()?;

lofty/src/ape/tag/mod.rs

@@ -622,9 +622,11 @@ mod tests {
 		let tag = crate::tag::utils::test_utils::read_path("tests/tags/assets/test.apev2");
 		let mut reader = Cursor::new(tag);
 
-		let (parsed_tag, _) = crate::ape::tag::read::read_ape_tag(&mut reader, false)
-			.unwrap()
-			.unwrap();
+		let (Some(parsed_tag), _) =
+			crate::ape::tag::read::read_ape_tag(&mut reader, false, true).unwrap()
+		else {
+			unreachable!();
+		};
 
 		assert_eq!(expected_tag.len(), parsed_tag.len());
 
@@ -638,9 +640,11 @@ mod tests {
 		let tag_bytes = crate::tag::utils::test_utils::read_path("tests/tags/assets/test.apev2");
 		let mut reader = Cursor::new(tag_bytes);
 
-		let (parsed_tag, _) = crate::ape::tag::read::read_ape_tag(&mut reader, false)
-			.unwrap()
-			.unwrap();
+		let (Some(parsed_tag), _) =
+			crate::ape::tag::read::read_ape_tag(&mut reader, false, true).unwrap()
+		else {
+			unreachable!();
+		};
 
 		let mut writer = Vec::new();
 		parsed_tag
@@ -649,9 +653,11 @@ mod tests {
 
 		let mut temp_reader = Cursor::new(writer);
 
-		let (temp_parsed_tag, _) = crate::ape::tag::read::read_ape_tag(&mut temp_reader, false)
-			.unwrap()
-			.unwrap();
+		let (Some(temp_parsed_tag), _) =
+			crate::ape::tag::read::read_ape_tag(&mut temp_reader, false, true).unwrap()
+		else {
+			unreachable!()
+		};
 
 		assert_eq!(parsed_tag, temp_parsed_tag);
 	}
@@ -661,9 +667,10 @@ mod tests {
 		let tag_bytes = crate::tag::utils::test_utils::read_path("tests/tags/assets/test.apev2");
 		let mut reader = Cursor::new(tag_bytes);
 
-		let (ape, _) = crate::ape::tag::read::read_ape_tag(&mut reader, false)
-			.unwrap()
-			.unwrap();
+		let (Some(ape), _) = crate::ape::tag::read::read_ape_tag(&mut reader, false, true).unwrap()
+		else {
+			unreachable!()
+		};
 
 		let tag: Tag = ape.into();
 

lofty/src/ape/tag/read.rs

@@ -86,16 +86,20 @@ where
 pub(crate) fn read_ape_tag<R: Read + Seek>(
 	reader: &mut R,
 	footer: bool,
-) -> Result<Option<(ApeTag, ApeHeader)>> {
+	read_tag: bool,
+) -> Result<(Option<ApeTag>, Option<ApeHeader>)> {
 	let mut ape_preamble = [0; 8];
 	reader.read_exact(&mut ape_preamble)?;
 
+	let mut ape_tag = None;
 	if &ape_preamble == APE_PREAMBLE {
 		let ape_header = header::read_ape_header(reader, footer)?;
+		if read_tag {
+			ape_tag = Some(read_ape_tag_with_header(reader, ape_header)?);
+		}
 
-		let ape = read_ape_tag_with_header(reader, ape_header)?;
-		return Ok(Some((ape, ape_header)));
+		return Ok((ape_tag, Some(ape_header)));
 	}
 
-	Ok(None)
+	Ok((None, None))
 }

lofty/src/ape/tag/write.rs

@@ -48,8 +48,8 @@ where
 	let mut header_ape_tag = (false, (0, 0));
 
 	let start = file.stream_position()?;
-	match read::read_ape_tag(file, false)? {
-		Some((mut existing_tag, header)) => {
+	match read::read_ape_tag(file, false, true)? {
+		(Some(mut existing_tag), Some(header)) => {
 			if write_options.respect_read_only {
 				// Only keep metadata around that's marked read only
 				existing_tag.items.retain(|i| i.read_only);
@@ -61,7 +61,7 @@ where
 
 			header_ape_tag = (true, (start, start + u64::from(header.size)))
 		},
-		None => {
+		_ => {
 			file.seek(SeekFrom::Current(-8))?;
 		},
 	}
@@ -80,7 +80,7 @@ where
 
 	// Also check this tag for any read only items
 	let start = file.stream_position()? as usize + 32;
-	if let Some((mut existing_tag, header)) = read::read_ape_tag(file, true)? {
+	if let (Some(mut existing_tag), Some(header)) = read::read_ape_tag(file, true, true)? {
 		if write_options.respect_read_only {
 			existing_tag.items.retain(|i| i.read_only);
 

lofty/src/config/parse_options.rs

@@ -3,6 +3,7 @@
 #[non_exhaustive]
 pub struct ParseOptions {
 	pub(crate) read_properties: bool,
+	pub(crate) read_tags: bool,
 	pub(crate) parsing_mode: ParsingMode,
 	pub(crate) max_junk_bytes: usize,
 }
@@ -15,6 +16,7 @@ impl Default for ParseOptions {
 	/// ```rust,ignore
 	/// ParseOptions {
 	/// 	read_properties: true,
+	///     read_tags: true,
 	/// 	parsing_mode: ParsingMode::BestAttempt,
 	///     max_junk_bytes: 1024
 	/// }
@@ -46,6 +48,7 @@ impl ParseOptions {
 	pub const fn new() -> Self {
 		Self {
 			read_properties: true,
+			read_tags: true,
 			parsing_mode: Self::DEFAULT_PARSING_MODE,
 			max_junk_bytes: Self::DEFAULT_MAX_JUNK_BYTES,
 		}
@@ -66,6 +69,21 @@ impl ParseOptions {
 		*self
 	}
 
+	/// Whether or not to read the tags
+	///
+	/// # Examples
+	///
+	/// ```rust
+	/// use lofty::config::ParseOptions;
+	///
+	/// // By default, `read_tags` is enabled. Here, we don't want to read them.
+	/// let parsing_options = ParseOptions::new().read_tags(false);
+	/// ```
+	pub fn read_tags(&mut self, read_tags: bool) -> Self {
+		self.read_tags = read_tags;
+		*self
+	}
+
 	/// The parsing mode to use, see [`ParsingMode`] for details
 	///
 	/// # Examples

lofty/src/flac/read.rs

@@ -47,10 +47,14 @@ where
 		properties: FlacProperties::default(),
 	};
 
+	let find_id3v2_config = if parse_options.read_tags {
+		FindId3v2Config::READ_TAG
+	} else {
+		FindId3v2Config::NO_READ_TAG
+	};
+
 	// It is possible for a FLAC file to contain an ID3v2 tag
-	if let ID3FindResults(Some(header), Some(content)) =
-		find_id3v2(data, FindId3v2Config::READ_TAG)?
-	{
+	if let ID3FindResults(Some(header), Some(content)) = find_id3v2(data, find_id3v2_config)? {
 		log::warn!("Encountered an ID3v2 tag. This tag cannot be rewritten to the FLAC file!");
 
 		let reader = &mut &*content;
@@ -78,7 +82,7 @@ where
 			decode_err!(@BAIL Flac, "Encountered a zero-sized metadata block");
 		}
 
-		if block.ty == BLOCK_ID_VORBIS_COMMENTS {
+		if block.ty == BLOCK_ID_VORBIS_COMMENTS && parse_options.read_tags {
 			log::debug!("Encountered a Vorbis Comments block, parsing");
 
 			// NOTE: According to the spec
@@ -106,7 +110,7 @@ where
 			continue;
 		}
 
-		if block.ty == BLOCK_ID_PICTURE {
+		if block.ty == BLOCK_ID_PICTURE && parse_options.read_tags {
 			log::debug!("Encountered a FLAC picture block, parsing");
 
 			match Picture::from_flac_bytes(&block.content, false, parse_options.parsing_mode) {

lofty/src/iff/aiff/read.rs

@@ -69,7 +69,7 @@ where
 
 	while chunks.next(data).is_ok() {
 		match &chunks.fourcc {
-			b"ID3 " | b"id3 " => {
+			b"ID3 " | b"id3 " if parse_options.read_tags => {
 				let tag = chunks.id3_chunk(data, parse_options.parsing_mode)?;
 				if let Some(existing_tag) = id3v2_tag.as_mut() {
 					log::warn!("Duplicate ID3v2 tag found, appending frames to previous tag");
@@ -95,12 +95,12 @@ where
 				stream_len = chunks.size;
 				chunks.skip(data)?;
 			},
-			b"ANNO" => {
+			b"ANNO" if parse_options.read_tags => {
 				annotations.push(chunks.read_pstring(data, None)?);
 			},
 			// These four chunks are expected to appear at most once per file,
 			// so there's no need to replace anything we already read
-			b"COMT" if comments.is_empty() => {
+			b"COMT" if comments.is_empty() && parse_options.read_tags => {
 				if chunks.size < 2 {
 					continue;
 				}
@@ -123,13 +123,13 @@ where
 
 				chunks.correct_position(data)?;
 			},
-			b"NAME" if text_chunks.name.is_none() => {
+			b"NAME" if text_chunks.name.is_none() && parse_options.read_tags => {
 				text_chunks.name = Some(chunks.read_pstring(data, None)?);
 			},
-			b"AUTH" if text_chunks.author.is_none() => {
+			b"AUTH" if text_chunks.author.is_none() && parse_options.read_tags => {
 				text_chunks.author = Some(chunks.read_pstring(data, None)?);
 			},
-			b"(c) " if text_chunks.copyright.is_none() => {
+			b"(c) " if text_chunks.copyright.is_none() && parse_options.read_tags => {
 				text_chunks.copyright = Some(chunks.read_pstring(data, None)?);
 			},
 			_ => chunks.skip(data)?,

lofty/src/iff/wav/read.rs

@@ -78,7 +78,7 @@ where
 				data.read_exact(&mut list_type)?;
 
 				match &list_type {
-					b"INFO" => {
+					b"INFO" if parse_options.read_tags => {
 						let end = data.stream_position()? + u64::from(chunks.size - 4);
 						super::tag::read::parse_riff_info(data, &mut chunks, end, &mut riff_info)?;
 					},
@@ -88,7 +88,7 @@ where
 					},
 				}
 			},
-			b"ID3 " | b"id3 " => {
+			b"ID3 " | b"id3 " if parse_options.read_tags => {
 				let tag = chunks.id3_chunk(data, parse_options.parsing_mode)?;
 				if let Some(existing_tag) = id3v2_tag.as_mut() {
 					log::warn!("Duplicate ID3v2 tag found, appending frames to previous tag");