Merge changes I6cd6ff18,I686e0558,I2532bf2b,I11416277,I97bdd2bf (a100e31e) · Commits · e / os / android_packages_modules_Bluetooth

tools/pdl/Android.bp

+3 −6

Original line number	Diff line number	Diff line
		@@ -9,7 +9,6 @@ package {

		rust_defaults {
		name: "pdl_defaults",
		srcs: ["src/main.rs"],
		// LINT.IfChange
		rustlibs: [
		"libcodespan_reporting",
		@@ -31,11 +30,13 @@ rust_defaults {
		rust_binary_host {
		name: "pdl",
		defaults: ["pdl_defaults"],
		srcs: ["src/main.rs"],
		}

		rust_test_host {
		name: "pdl_inline_tests",
		defaults: ["pdl_defaults"],
		srcs: ["src/main.rs"],
		test_suites: ["general-tests"],
		enabled: false, // rustfmt is only available on x86.
		arch: {
		@@ -57,6 +58,7 @@ rust_test_host {

		rust_test_host {
		name: "pdl_tests",
		defaults: ["pdl_defaults"],
		srcs: ["tests/pdl_tests.rs"],
		test_suites: ["general-tests"],
		enabled: false, // rustfmt is only available on x86.
		@@ -65,11 +67,6 @@ rust_test_host {
		enabled: true,
		},
		},
		// LINT.IfChange
		rustlibs: [
		"libtempfile",
		],
		// LINT.ThenChange(Cargo.toml)
		data: [
		":bluetooth_packetgen",
		":pdl",

tools/pdl/src/backends/rust.rs

+6 −490

Original line number	Diff line number	Diff line
		@@ -43,204 +43,11 @@ pub fn get_field_range(offset: usize, width: usize) -> std::ops::Range<usize> {
		start..end
		}

		/// Read data for a byte-aligned chunk.
		fn generate_chunk_read(
		packet_name: &str,
		endianness_value: ast::EndiannessValue,
		offset: usize,
		chunk: &Chunk,
		) -> proc_macro2::TokenStream {
		assert!(offset % 8 == 0, "Chunks must be byte-aligned, got offset: {offset}");
		let getter = match endianness_value {
		ast::EndiannessValue::BigEndian => format_ident!("from_be_bytes"),
		ast::EndiannessValue::LittleEndian => format_ident!("from_le_bytes"),
		};

		// Work directly with the field name if we are reading a single
		// field. This generates simpler code.
		let chunk_name = chunk.get_name();
		let chunk_width = chunk.get_width();
		let chunk_type = types::Integer::new(chunk_width);
		assert!(chunk_width % 8 == 0, "Chunks must have a byte size, got width: {chunk_width}");

		let range = get_field_range(offset, chunk_width);
		let indices = range.map(syn::Index::from).collect::<Vec<_>>();

		// TODO(mgeisler): emit just a single length check per chunk. We
		// could even emit a single length check per packet.
		let length_checks = chunk.generate_length_checks(packet_name, offset);

		// When the chunk_type.width is larger than chunk_width (e.g.
		// chunk_width is 24 but chunk_type.width is 32), then we need
		// zero padding.
		let zero_padding_len = (chunk_type.width - chunk_width) / 8;
		// We need the padding on the MSB side of the payload, so for
		// big-endian, we need to padding on the left, for little-endian
		// we need it on the right.
		let (zero_padding_before, zero_padding_after) = match endianness_value {
		ast::EndiannessValue::BigEndian => (vec![syn::Index::from(0); zero_padding_len], vec![]),
		ast::EndiannessValue::LittleEndian => (vec![], vec![syn::Index::from(0); zero_padding_len]),
		};

		quote! {
		#(#length_checks)*
		let #chunk_name = #chunk_type::#getter([
		#(#zero_padding_before,)* #(bytes[#indices]),* #(, #zero_padding_after)*
		]);
		}
		}

		fn generate_chunk_read_field_adjustments(fields: &[ast::Field]) -> proc_macro2::TokenStream {
		// If there is a single field in the chunk, then we don't have to
		// shift, mask, or cast.
		if fields.len() == 1 {
		return quote! {};
		}

		let chunk_fields = fields.iter().map(Field::from).collect::<Vec<_>>();
		let chunk_width = Chunk::new(&chunk_fields).get_width();
		let chunk_type = types::Integer::new(chunk_width);

		let mut field_parsers = Vec::new();
		let mut field_offset = 0;
		for field in fields {
		let field_name = Field::from(field).get_ident();
		match field {
		ast::Field::Scalar { width, .. } => {
		let field_type = types::Integer::new(*width);

		let mut field = quote! {
		chunk
		};
		if field_offset > 0 {
		let field_offset = syn::Index::from(field_offset);
		let op = syn::parse_str::<syn::BinOp>(">>").unwrap();
		field = quote! {
		(#field #op #field_offset)
		};
		}

		if *width < field_type.width {
		let bit_mask = mask_bits(*width);
		field = quote! {
		(#field & #bit_mask)
		};
		}

		if field_type.width < chunk_type.width {
		field = quote! {
		#field as #field_type;
		};
		}

		field_offset += width;
		field_parsers.push(quote! {
		let #field_name = #field;
		});
		}
		_ => todo!("unsupported field: {:?}", field),
		}
		}

		quote! {
		#(#field_parsers)*
		}
		}

		fn generate_chunk_write_field_adjustments(chunk: &[ast::Field]) -> proc_macro2::TokenStream {
		// Work directly with the field name if we are writing a single
		// field. This generates simpler code.
		if let [ast::Field::Scalar { id, .. }] = chunk {
		// If there is a single field in the chunk, then we don't have to
		// shift, mask, or cast.
		let field_name = format_ident!("{id}");
		return quote! {
		let #field_name = self.#field_name;
		};
		}

		let chunk_fields = chunk.iter().map(Field::from).collect::<Vec<_>>();
		let chunk_width = Chunk::new(&chunk_fields).get_width();
		let chunk_type = types::Integer::new(chunk_width);

		let mut field_parsers = Vec::new();
		let mut field_offset = 0;
		for field in chunk {
		match field {
		ast::Field::Scalar { id, width, .. } => {
		let field_name = format_ident!("{id}");
		let field_type = types::Integer::new(*width);

		let mut field = quote! {
		self.#field_name
		};

		if field_type.width < chunk_type.width {
		field = quote! {
		(#field as #chunk_type)
		};
		}

		if *width < field_type.width {
		let bit_mask = mask_bits(*width);
		field = quote! {
		(#field & #bit_mask)
		};
		}

		if field_offset > 0 {
		let field_offset = syn::Index::from(field_offset);
		let op = syn::parse_str::<syn::BinOp>("<<").unwrap();
		field = quote! {
		(#field #op #field_offset)
		};
		}

		field_offset += width;
		field_parsers.push(quote! {
		let chunk = chunk \| #field;
		});
		}
		_ => todo!("unsupported field: {:?}", field),
		}
		}

		quote! {
		let chunk = 0;
		#(#field_parsers)*
		}
		}

		/// Generate a bit-mask which masks out `n` least significant bits.
		fn mask_bits(n: usize) -> syn::LitInt {
		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,
		@@ -343,18 +150,10 @@ fn generate_packet_decl(
		let mut offset = 0;
		for chunk in chunks {
		let chunk_fields = chunk.iter().map(Field::from).collect::<Vec<_>>();
		field_parsers.push(generate_chunk_read(
		id,
		file.endianness.value,
		offset,
		&Chunk::new(&chunk_fields),
		));
		field_parsers.push(generate_chunk_read_field_adjustments(chunk));

		field_writers.push(generate_chunk_write_field_adjustments(chunk));
		field_writers.push(generate_chunk_write(file.endianness.value, offset, chunk));

		offset += Chunk::new(&chunk_fields).get_width();
		let chunk = Chunk::new(&chunk_fields);
		field_parsers.push(chunk.generate_read(id, file.endianness.value, offset));
		field_writers.push(chunk.generate_write(file.endianness.value, offset));
		offset += chunk.get_width();
		}

		let field_names = fields.iter().map(\|field\| Field::from(field).get_ident()).collect::<Vec<_>>();
		@@ -531,9 +330,8 @@ pub fn generate(sources: &ast::SourceDatabase, file: &ast::File) -> String {
		mod tests {
		use super::*;
		use crate::ast;
		use crate::backends::rust::field::ScalarField;
		use crate::parser::parse_inline;
		use crate::test_utils::{assert_eq_with_diff, assert_snapshot_eq, rustfmt};
		use crate::test_utils::{assert_snapshot_eq, rustfmt};

		/// Parse a string fragment as a PDL file.
		///
		@@ -679,286 +477,4 @@ mod tests {
		assert_eq!(get_field_range(/offset=/ 5, /width=/ 4), (0..2));
		assert_eq!(get_field_range(/offset=/ 5, /width=/ 20), (0..4));
		}

		// Assert that an expression equals the given expression.
		//
		// Both expressions are wrapped in a `main` function (so we can
		// format it with `rustfmt`) and a diff is be shown if they
		// differ.
		#[track_caller]
		fn assert_expr_eq(left: proc_macro2::TokenStream, right: proc_macro2::TokenStream) {
		let left = quote! {
		fn main() { #left }
		};
		let right = quote! {
		fn main() { #right }
		};
		assert_eq_with_diff(
		"left",
		&rustfmt(&left.to_string()),
		"right",
		&rustfmt(&right.to_string()),
		);
		}

		#[test]
		fn test_generate_chunk_read_8bit() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 8 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		generate_chunk_read("Foo", ast::EndiannessValue::BigEndian, 80, &chunk),
		quote! {
		if bytes.len() < 11 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 11,
		got: bytes.len(),
		});
		}
		let a = u8::from_be_bytes([bytes[10]]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_16bit_le() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 16 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		generate_chunk_read("Foo", ast::EndiannessValue::LittleEndian, 80, &chunk),
		quote! {
		if bytes.len() < 12 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 12,
		got: bytes.len(),
		});
		}
		let a = u16::from_le_bytes([bytes[10], bytes[11]]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_16bit_be() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 16 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		generate_chunk_read("Foo", ast::EndiannessValue::BigEndian, 80, &chunk),
		quote! {
		if bytes.len() < 12 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 12,
		got: bytes.len(),
		});
		}
		let a = u16::from_be_bytes([bytes[10], bytes[11]]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_24bit_le() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 24 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		generate_chunk_read("Foo", ast::EndiannessValue::LittleEndian, 80, &chunk),
		quote! {
		if bytes.len() < 13 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 13,
		got: bytes.len(),
		});
		}
		let a = u32::from_le_bytes([bytes[10], bytes[11], bytes[12], 0]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_24bit_be() {
		let fields = [Field::Scalar(ScalarField { id: String::from("a"), width: 24 })];
		let chunk = Chunk::new(&fields);
		assert_expr_eq(
		generate_chunk_read("Foo", ast::EndiannessValue::BigEndian, 80, &chunk),
		quote! {
		if bytes.len() < 13 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 13,
		got: bytes.len(),
		});
		}
		let a = u32::from_be_bytes([0, bytes[10], bytes[11], bytes[12]]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_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(
		generate_chunk_read("Foo", ast::EndiannessValue::BigEndian, 80, &chunk),
		quote! {
		if bytes.len() < 12 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "a".to_string(),
		wanted: 12,
		got: bytes.len(),
		});
		}
		if bytes.len() < 15 {
		return Err(Error::InvalidLengthError {
		obj: "Foo".to_string(),
		field: "b".to_string(),
		wanted: 15,
		got: bytes.len(),
		});
		}
		let chunk =
		u64::from_be_bytes([0, 0, 0, bytes[10], bytes[11], bytes[12], bytes[13], bytes[14]]);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_field_adjustments_8bit() {
		let loc = ast::SourceRange::default();
		let fields = vec![
		ast::Field::Scalar { loc, id: String::from("a"), width: 3 },
		ast::Field::Scalar { loc, id: String::from("b"), width: 5 },
		];
		assert_expr_eq(
		generate_chunk_read_field_adjustments(&fields),
		quote! {
		let a = (chunk & 0x7);
		let b = ((chunk >> 3) & 0x1f);
		},
		);
		}

		#[test]
		fn test_generate_chunk_read_field_adjustments_48bit() {
		let loc = ast::SourceRange::default();
		let fields = vec![
		ast::Field::Scalar { loc, id: String::from("a"), width: 3 },
		ast::Field::Scalar { loc, id: String::from("b"), width: 8 },
		ast::Field::Scalar { loc, id: String::from("c"), width: 10 },
		ast::Field::Scalar { loc, id: String::from("d"), width: 18 },
		ast::Field::Scalar { loc, id: String::from("e"), width: 9 },
		];
		assert_expr_eq(
		generate_chunk_read_field_adjustments(&fields),
		quote! {
		let a = (chunk & 0x7) as u8;
		let b = (chunk >> 3) as u8;
		let c = ((chunk >> 11) & 0x3ff) as u16;
		let d = ((chunk >> 21) & 0x3ffff) as u32;
		let e = ((chunk >> 39) & 0x1ff) as u16;
		},
		);
		}

		#[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();
		let fields = vec![
		ast::Field::Scalar { loc, id: String::from("a"), width: 3 },
		ast::Field::Scalar { loc, id: String::from("b"), width: 5 },
		];
		assert_expr_eq(
		generate_chunk_write_field_adjustments(&fields),
		quote! {
		let chunk = 0;
		let chunk = chunk \| (self.a & 0x7) ;
		let chunk = chunk \| ((self.b & 0x1f) << 3);
		},
		);
		}

		#[test]
		fn test_generate_chunk_write_field_adjustments_48bit() {
		let loc = ast::SourceRange::default();
		let fields = vec![
		ast::Field::Scalar { loc, id: String::from("a"), width: 3 },
		ast::Field::Scalar { loc, id: String::from("b"), width: 8 },
		ast::Field::Scalar { loc, id: String::from("c"), width: 10 },
		ast::Field::Scalar { loc, id: String::from("d"), width: 18 },
		ast::Field::Scalar { loc, id: String::from("e"), width: 9 },
		];
		assert_expr_eq(
		generate_chunk_write_field_adjustments(&fields),
		quote! {
		let chunk = 0;
		let chunk = chunk \| ((self.a as u64) & 0x7);
		let chunk = chunk \| ((self.b as u64) << 3);
		let chunk = chunk \| (((self.c as u64) & 0x3ff) << 11);
		let chunk = chunk \| (((self.d as u64) & 0x3ffff) << 21);
		let chunk = chunk \| (((self.e as u64) & 0x1ff) << 39);
		},
		);
		}
		}

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

+404 −0

File changed.

Preview size limit exceeded, changes collapsed.

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

+101 −2

Original line number	Diff line number	Diff line
		use quote::{format_ident, quote};

		use crate::ast;
		use crate::backends::rust::mask_bits;
		use crate::backends::rust::types;

		/// Like [`ast::Field::Scalar`].
		@@ -27,9 +28,13 @@ impl ScalarField {
		format_ident!("{}", self.id)
		}

		fn get_type(&self) -> types::Integer {
		types::Integer::new(self.width)
		}

		fn generate_decl(&self, visibility: syn::Visibility) -> proc_macro2::TokenStream {
		let field_name = self.get_ident();
		let field_type = types::Integer::new(self.width);
		let field_type = self.get_type();
		quote! {
		#visibility #field_name: #field_type
		}
		@@ -38,13 +43,87 @@ impl ScalarField {
		fn generate_getter(&self, packet_name: &syn::Ident) -> proc_macro2::TokenStream {
		let field_name = self.get_ident();
		let getter_name = format_ident!("get_{}", self.id);
		let field_type = types::Integer::new(self.width);
		let field_type = self.get_type();
		quote! {
		pub fn #getter_name(&self) -> #field_type {
		self.#packet_name.as_ref().#field_name
		}
		}
		}

		fn generate_read_adjustment(
		&self,
		offset: usize,
		chunk_type: types::Integer,
		) -> proc_macro2::TokenStream {
		let field_name = self.get_ident();
		let field_type = self.get_type();
		let mut field = quote! {
		chunk
		};
		if offset > 0 {
		let offset = syn::Index::from(offset);
		let op = syn::parse_str::<syn::BinOp>(">>").unwrap();
		field = quote! {
		(#field #op #offset)
		};
		}

		if self.width < field_type.width {
		let bit_mask = mask_bits(self.width);
		field = quote! {
		(#field & #bit_mask)
		};
		}

		if field_type.width < chunk_type.width {
		field = quote! {
		#field as #field_type;
		};
		}

		quote! {
		let #field_name = #field;
		}
		}

		fn generate_write_adjustment(
		&self,
		offset: usize,
		chunk_type: types::Integer,
		) -> proc_macro2::TokenStream {
		let field_name = self.get_ident();
		let field_type = self.get_type();

		let mut field = quote! {
		self.#field_name
		};

		if field_type.width < chunk_type.width {
		field = quote! {
		(#field as #chunk_type)
		};
		}

		if self.width < field_type.width {
		let bit_mask = mask_bits(self.width);
		field = quote! {
		(#field & #bit_mask)
		};
		}

		if offset > 0 {
		let field_offset = syn::Index::from(offset);
		let op = syn::parse_str::<syn::BinOp>("<<").unwrap();
		field = quote! {
		(#field #op #field_offset)
		};
		}

		quote! {
		let chunk = chunk \| #field;
		}
		}
		}

		/// Projection of [`ast::Field`] with the bits needed for the Rust
		@@ -93,4 +172,24 @@ impl Field {
		Field::Scalar(field) => field.generate_getter(packet_name),
		}
		}

		pub fn generate_read_adjustment(
		&self,
		offset: usize,
		chunk_type: types::Integer,
		) -> proc_macro2::TokenStream {
		match self {
		Field::Scalar(field) => field.generate_read_adjustment(offset, chunk_type),
		}
		}

		pub fn generate_write_adjustment(
		&self,
		offset: usize,
		chunk_type: types::Integer,
		) -> proc_macro2::TokenStream {
		match self {
		Field::Scalar(field) => field.generate_write_adjustment(offset, chunk_type),
		}
		}
		}

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

+1 −0

Original line number	Diff line number	Diff line
		//! Utility functions for dealing with Rust integer types.

		/// A Rust integer type such as `u8`.
		#[derive(Copy, Clone)]
		pub struct Integer {
		pub width: usize,
		}