pdl: add ‘Chunk::generate_write’ (cca1f564) · Commits · e / os / android_packages_modules_Bluetooth

tools/pdl/src/backends/rust.rs

+1 −77

Original line number	Diff line number	Diff line
		@@ -112,31 +112,6 @@ pub fn mask_bits(n: usize) -> syn::LitInt {
		syn::parse_str::<syn::LitInt>(&format!("{:#x}", (1u64 << n) - 1)).unwrap()
		}

		fn generate_chunk_write(
		endianness_value: ast::EndiannessValue,
		offset: usize,
		chunk: &[ast::Field],
		) -> proc_macro2::TokenStream {
		let writer = match endianness_value {
		ast::EndiannessValue::BigEndian => format_ident!("to_be_bytes"),
		ast::EndiannessValue::LittleEndian => format_ident!("to_le_bytes"),
		};

		let chunk_fields = chunk.iter().map(Field::from).collect::<Vec<_>>();
		let chunk_width = Chunk::new(&chunk_fields).get_width();
		let chunk_name = Chunk::new(&chunk_fields).get_name();
		assert!(chunk_width % 8 == 0, "Chunks must have a byte size, got width: {chunk_width}");

		let range = get_field_range(offset, chunk_width);
		let start = syn::Index::from(range.start);
		let end = syn::Index::from(range.end);
		// TODO(mgeisler): let slice = (chunk_type_width > chunk_width).then( ... )
		let chunk_byte_width = syn::Index::from(chunk_width / 8);
		quote! {
		buffer[#start..#end].copy_from_slice(&#chunk_name.#writer()[0..#chunk_byte_width]);
		}
		}

		/// Generate code for an `ast::Decl::Packet` enum value.
		fn generate_packet_decl(
		file: &ast::File,
		@@ -246,7 +221,7 @@ fn generate_packet_decl(
		));

		field_writers.push(generate_chunk_write_field_adjustments(chunk));
		field_writers.push(generate_chunk_write(file.endianness.value, offset, chunk));
		field_writers.push(Chunk::new(&chunk_fields).generate_write(file.endianness.value, offset));

		offset += Chunk::new(&chunk_fields).get_width();
		}
		@@ -573,57 +548,6 @@ mod tests {
		assert_eq!(get_field_range(/offset=/ 5, /width=/ 20), (0..4));
		}

		#[test]
		fn test_generate_chunk_write_8bit() {
		let loc = ast::SourceRange::default();
		let fields = &[ast::Field::Scalar { loc, id: String::from("a"), width: 8 }];
		assert_expr_eq(
		generate_chunk_write(ast::EndiannessValue::BigEndian, 80, fields),
		quote! {
		buffer[10..11].copy_from_slice(&a.to_be_bytes()[0..1]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_write_16bit() {
		let loc = ast::SourceRange::default();
		let fields = &[ast::Field::Scalar { loc, id: String::from("a"), width: 16 }];
		assert_expr_eq(
		generate_chunk_write(ast::EndiannessValue::BigEndian, 80, fields),
		quote! {
		buffer[10..12].copy_from_slice(&a.to_be_bytes()[0..2]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_write_24bit() {
		let loc = ast::SourceRange::default();
		let fields = &[ast::Field::Scalar { loc, id: String::from("a"), width: 24 }];
		assert_expr_eq(
		generate_chunk_write(ast::EndiannessValue::BigEndian, 80, fields),
		quote! {
		buffer[10..13].copy_from_slice(&a.to_be_bytes()[0..3]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_write_multiple_fields() {
		let loc = ast::SourceRange::default();
		let fields = &[
		ast::Field::Scalar { loc, id: String::from("a"), width: 16 },
		ast::Field::Scalar { loc, id: String::from("b"), width: 24 },
		];
		assert_expr_eq(
		generate_chunk_write(ast::EndiannessValue::BigEndian, 80, fields),
		quote! {
		buffer[10..15].copy_from_slice(&chunk.to_be_bytes()[0..5]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_write_field_adjustments_8bit() {
		let loc = ast::SourceRange::default();

tools/pdl/src/backends/rust/chunk.rs

+75 −0

Original line number	Diff line number	Diff line
		@@ -141,6 +141,30 @@ impl Chunk<'_> {
		#(#field_parsers)*
		}
		}

		pub fn generate_write(
		&self,
		endianness_value: ast::EndiannessValue,
		offset: usize,
		) -> proc_macro2::TokenStream {
		let writer = match endianness_value {
		ast::EndiannessValue::BigEndian => format_ident!("to_be_bytes"),
		ast::EndiannessValue::LittleEndian => format_ident!("to_le_bytes"),
		};

		let chunk_width = self.get_width();
		let chunk_name = self.get_name();
		assert!(chunk_width % 8 == 0, "Chunks must have a byte size, got width: {chunk_width}");

		let range = get_field_range(offset, chunk_width);
		let start = syn::Index::from(range.start);
		let end = syn::Index::from(range.end);
		// TODO(mgeisler): let slice = (chunk_type_width > chunk_width).then( ... )
		let chunk_byte_width = syn::Index::from(chunk_width / 8);
		quote! {
		buffer[#start..#end].copy_from_slice(&#chunk_name.#writer()[0..#chunk_byte_width]);
		}
		}
		}

		#[cfg(test)]
		@@ -320,4 +344,55 @@ mod tests {
		},
		);
		}

		#[test]
		fn test_generate_write_8bit() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 8 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		chunk.generate_write(ast::EndiannessValue::BigEndian, 80),
		quote! {
		buffer[10..11].copy_from_slice(&a.to_be_bytes()[0..1]);
		},
		);
		}

		#[test]
		fn test_generate_write_16bit() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 16 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		chunk.generate_write(ast::EndiannessValue::BigEndian, 80),
		quote! {
		buffer[10..12].copy_from_slice(&a.to_be_bytes()[0..2]);
		},
		);
		}

		#[test]
		fn test_generate_write_24bit() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 24 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		chunk.generate_write(ast::EndiannessValue::BigEndian, 80),
		quote! {
		buffer[10..13].copy_from_slice(&a.to_be_bytes()[0..3]);
		},
		);
		}

		#[test]
		fn test_generate_write_multiple_fields() {
		let fields = [
		Field::Scalar(ScalarField { id: String::from("a"), width: 16 }),
		Field::Scalar(ScalarField { id: String::from("b"), width: 24 }),
		];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		chunk.generate_write(ast::EndiannessValue::BigEndian, 80),
		quote! {
		buffer[10..15].copy_from_slice(&chunk.to_be_bytes()[0..5]);
		},
		);
		}
		}