From: Marc-André Lureau <marcandre.lur...@redhat.com> Generate high-level idiomatic Rust code for the QAPI types, with to/from translations for the C FFI.
- char* is mapped to String, scalars to there corresponding Rust types - enums are simply aliased from FFI - has_foo/foo members are mapped to Option<T> - lists are represented as Vec<T> - structures have Rust versions, with To/From FFI conversions - alternate are represented as Rust enum - unions are represented in a similar way as in C: a struct S with a "u" member (since S may have extra 'base' fields). However, the discriminant isn't a member of S, since Rust enum already include it. Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> Link: https://lore.kernel.org/r/20210907121943.3498701-21-marcandre.lur...@redhat.com Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- meson.build | 4 +- scripts/qapi/backend.py | 4 +- scripts/qapi/main.py | 4 +- scripts/qapi/rs.py | 183 ++++++++++++++++++++++ scripts/qapi/rs_types.py | 320 +++++++++++++++++++++++++++++++++++++++ 5 files changed, 511 insertions(+), 4 deletions(-) create mode 100644 scripts/qapi/rs.py create mode 100644 scripts/qapi/rs_types.py diff --git a/meson.build b/meson.build index 967a10e80b8..cdfbc7241fb 100644 --- a/meson.build +++ b/meson.build @@ -3531,12 +3531,14 @@ qapi_gen_depends = [ meson.current_source_dir() / 'scripts/qapi/__init__.py', meson.current_source_dir() / 'scripts/qapi/introspect.py', meson.current_source_dir() / 'scripts/qapi/main.py', meson.current_source_dir() / 'scripts/qapi/parser.py', + meson.current_source_dir() / 'scripts/qapi/rs_types.py', meson.current_source_dir() / 'scripts/qapi/schema.py', meson.current_source_dir() / 'scripts/qapi/source.py', meson.current_source_dir() / 'scripts/qapi/types.py', meson.current_source_dir() / 'scripts/qapi/features.py', meson.current_source_dir() / 'scripts/qapi/visit.py', - meson.current_source_dir() / 'scripts/qapi-gen.py' + meson.current_source_dir() / 'scripts/qapi-gen.py', + meson.current_source_dir() / 'scripts/qapi/rs.py', ] tracetool = [ diff --git a/scripts/qapi/backend.py b/scripts/qapi/backend.py index 14e60aa67af..2e76370c72d 100644 --- a/scripts/qapi/backend.py +++ b/scripts/qapi/backend.py @@ -9,6 +9,7 @@ from .introspect import gen_introspect from .schema import QAPISchema from .types import gen_types +from .rs_types import gen_rs_types from .visit import gen_visit @@ -35,7 +36,7 @@ def generate(self, """ -class QAPICBackend(QAPIBackend): +class QAPICodeBackend(QAPIBackend): def generate(self, schema: QAPISchema, @@ -55,6 +56,7 @@ def generate(self, :raise QAPIError: On failures. """ + gen_rs_types(schema, output_dir, prefix, builtins) gen_types(schema, output_dir, prefix, builtins) gen_features(schema, output_dir, prefix) gen_visit(schema, output_dir, prefix, builtins) diff --git a/scripts/qapi/main.py b/scripts/qapi/main.py index 0e2a6ae3f07..4ad75e213f5 100644 --- a/scripts/qapi/main.py +++ b/scripts/qapi/main.py @@ -12,7 +12,7 @@ import sys from typing import Optional -from .backend import QAPIBackend, QAPICBackend +from .backend import QAPIBackend, QAPICodeBackend from .common import must_match from .error import QAPIError from .schema import QAPISchema @@ -27,7 +27,7 @@ def invalid_prefix_char(prefix: str) -> Optional[str]: def create_backend(path: str) -> QAPIBackend: if path is None: - return QAPICBackend() + return QAPICodeBackend() module_path, dot, class_name = path.rpartition('.') if not dot: diff --git a/scripts/qapi/rs.py b/scripts/qapi/rs.py new file mode 100644 index 00000000000..c1e76e074fb --- /dev/null +++ b/scripts/qapi/rs.py @@ -0,0 +1,183 @@ +# This work is licensed under the terms of the GNU GPL, version 2. +# See the COPYING file in the top-level directory. +""" +QAPI Rust generator +""" + +import os +import re +import subprocess +from typing import NamedTuple, Optional + +from .common import POINTER_SUFFIX +from .gen import QAPIGen +from .schema import QAPISchemaModule, QAPISchemaVisitor + + +# see to_snake_case() below +snake_case = re.compile(r'((?<=[a-z0-9])[A-Z]|(?!^)[A-Z](?=[a-z]))') + + +rs_name_trans = str.maketrans('.-', '__') + + +# Map @name to a valid Rust identifier. +# If @protect, avoid returning certain ticklish identifiers (like +# keywords) by prepending raw identifier prefix 'r#'. +def rs_name(name: str, protect: bool = True) -> str: + name = name.translate(rs_name_trans) + if name[0].isnumeric(): + name = '_' + name + if not protect: + return name + # based from the list: + # https://doc.rust-lang.org/reference/keywords.html + if name in ('Self', 'abstract', 'as', 'async', + 'await', 'become', 'box', 'break', + 'const', 'continue', 'crate', 'do', + 'dyn', 'else', 'enum', 'extern', + 'false', 'final', 'fn', 'for', + 'if', 'impl', 'in', 'let', + 'loop', 'macro', 'match', 'mod', + 'move', 'mut', 'override', 'priv', + 'pub', 'ref', 'return', 'self', + 'static', 'struct', 'super', 'trait', + 'true', 'try', 'type', 'typeof', + 'union', 'unsafe', 'unsized', 'use', + 'virtual', 'where', 'while', 'yield'): + name = 'r#' + name + # avoid some clashes with the standard library + if name in ('String',): + name = 'Qapi' + name + + return name + + +def rs_type(c_type: str, + qapi_ns: Optional[str] = 'qapi::', + optional: Optional[bool] = False, + box: bool = False) -> str: + (is_pointer, _, is_list, c_type) = rs_ctype_parse(c_type) + # accepts QAPI types ('any', 'str', ...) as we translate + # qapiList to Rust FFI types here. + to_rs = { + 'any': 'QObject', + 'bool': 'bool', + 'char': 'i8', + 'double': 'f64', + 'int': 'i64', + 'int16': 'i16', + 'int16_t': 'i16', + 'int32': 'i32', + 'int32_t': 'i32', + 'int64': 'i64', + 'int64_t': 'i64', + 'int8': 'i8', + 'int8_t': 'i8', + 'null': 'QNull', + 'number': 'f64', + 'size': 'u64', + 'str': 'String', + 'uint16': 'u16', + 'uint16_t': 'u16', + 'uint32': 'u32', + 'uint32_t': 'u32', + 'uint64': 'u64', + 'uint64_t': 'u64', + 'uint8': 'u8', + 'uint8_t': 'u8', + 'String': 'QapiString', + } + if is_pointer: + to_rs.update({ + 'char': 'String', + }) + + if is_list: + c_type = c_type[:-4] + + to_rs = to_rs.get(c_type) + if to_rs: + ret = to_rs + else: + ret = qapi_ns + c_type + + if is_list: + ret = 'Vec<%s>' % ret + elif is_pointer and not to_rs and box: + ret = 'Box<%s>' % ret + if optional: + ret = 'Option<%s>' % ret + return ret + + +class CType(NamedTuple): + is_pointer: bool + is_const: bool + is_list: bool + c_type: str + + +def rs_ctype_parse(c_type: str) -> CType: + is_pointer = False + if c_type.endswith(POINTER_SUFFIX): + is_pointer = True + c_type = c_type[:-len(POINTER_SUFFIX)] + is_list = c_type.endswith('List') + is_const = False + if c_type.startswith('const '): + is_const = True + c_type = c_type[6:] + + c_type = rs_name(c_type) + return CType(is_pointer, is_const, is_list, c_type) + + +def to_camel_case(value: str) -> str: + # special case for last enum value + if value == '_MAX': + return value + raw_id = False + if value.startswith('r#'): + raw_id = True + value = value[2:] + value = ''.join('_' + word if word[0].isdigit() + else word[:1].upper() + word[1:] + for word in filter(None, re.split("[-_]+", value))) + if raw_id: + return 'r#' + value + return value + + +def to_snake_case(value: str) -> str: + return snake_case.sub(r'_\1', value).lower() + + +class QAPIGenRs(QAPIGen): + pass + + +class QAPISchemaRsVisitor(QAPISchemaVisitor): + + def __init__(self, prefix: str, what: str): + super().__init__() + self._prefix = prefix + self._what = what + self._gen = QAPIGenRs(self._prefix + self._what + '.rs') + self._main_module: Optional[str] = None + + def visit_module(self, name: Optional[str]) -> None: + if name is None: + return + if QAPISchemaModule.is_user_module(name): + if self._main_module is None: + self._main_module = name + + def write(self, output_dir: str) -> None: + self._gen.write(output_dir) + + pathname = os.path.join(output_dir, self._gen.fname) + try: + subprocess.check_call(['rustfmt', pathname]) + except FileNotFoundError: + pass diff --git a/scripts/qapi/rs_types.py b/scripts/qapi/rs_types.py new file mode 100644 index 00000000000..a182b33917a --- /dev/null +++ b/scripts/qapi/rs_types.py @@ -0,0 +1,320 @@ +# This work is licensed under the terms of the GNU GPL, version 2. +# See the COPYING file in the top-level directory. +""" +QAPI Rust types generator +""" + +from typing import List, Optional + +from .common import POINTER_SUFFIX, mcgen +from .rs import ( + QAPISchemaRsVisitor, + rs_ctype_parse, + rs_name, + rs_type, + to_camel_case, + to_snake_case, +) +from .schema import ( + QAPISchema, + QAPISchemaEnumMember, + QAPISchemaEnumType, + QAPISchemaFeature, + QAPISchemaIfCond, + QAPISchemaObjectType, + QAPISchemaObjectTypeMember, + QAPISchemaType, + QAPISchemaVariants, +) +from .source import QAPISourceInfo + + +objects_seen = set() + + +def gen_rs_variants_to_tag(name: str, + ifcond: QAPISchemaIfCond, + variants: Optional[QAPISchemaVariants]) -> str: + ret = mcgen(''' + +%(cfg)s +impl From<&%(rs_name)sVariant> for %(tag)s { + fn from(e: &%(rs_name)sVariant) -> Self { + match e { + ''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name), + tag=rs_type(variants.tag_member.type.c_type(), '')) + + for var in variants.variants: + type_name = var.type.name + var_name = to_camel_case(rs_name(var.name)) + patt = '(_)' + if type_name == 'q_empty': + patt = '' + ret += mcgen(''' + %(cfg)s + %(rs_name)sVariant::%(var_name)s%(patt)s => Self::%(var_name)s, +''', + cfg=var.ifcond.rsgen(), + rs_name=rs_name(name), + var_name=var_name, + patt=patt) + + ret += mcgen(''' + } + } +} +''') + return ret + + +def gen_rs_variants(name: str, + ifcond: QAPISchemaIfCond, + variants: Optional[QAPISchemaVariants]) -> str: + ret = mcgen(''' + +%(cfg)s +#[derive(Clone,Debug)] +pub enum %(rs_name)sVariant { +''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name)) + + for var in variants.variants: + type_name = var.type.name + var_name = to_camel_case(rs_name(var.name, False)) + if type_name == 'q_empty': + ret += mcgen(''' + %(cfg)s + %(var_name)s, +''', + cfg=var.ifcond.rsgen(), + var_name=var_name) + else: + c_type = var.type.c_unboxed_type() + if c_type.endswith('_wrapper'): + c_type = c_type[6:-8] # remove q_obj*-wrapper + ret += mcgen(''' + %(cfg)s + %(var_name)s(%(rs_type)s), +''', + cfg=var.ifcond.rsgen(), + var_name=var_name, + rs_type=rs_type(c_type, '')) + + ret += mcgen(''' +} +''') + + ret += gen_rs_variants_to_tag(name, ifcond, variants) + + return ret + + +def gen_rs_members(members: List[QAPISchemaObjectTypeMember], + exclude: List[str] = None) -> str: + exclude = exclude or [] + return [f"{m.ifcond.rsgen()} {to_snake_case(rs_name(m.name))}" + for m in members if m.name not in exclude] + + +def gen_struct_members(members: List[QAPISchemaObjectTypeMember]) -> str: + ret = '' + for memb in members: + typ = rs_type(memb.type.c_type(), '', optional=memb.optional, box=True) + ret += mcgen(''' + %(cfg)s + pub %(rs_name)s: %(rs_type)s, +''', + cfg=memb.ifcond.rsgen(), + rs_type=typ, + rs_name=to_snake_case(rs_name(memb.name))) + return ret + + +def gen_rs_object(name: str, + ifcond: QAPISchemaIfCond, + base: Optional[QAPISchemaObjectType], + members: List[QAPISchemaObjectTypeMember], + variants: Optional[QAPISchemaVariants]) -> str: + if name in objects_seen: + return '' + + if variants: + members = [m for m in members + if m.name != variants.tag_member.name] + + ret = '' + objects_seen.add(name) + + if variants: + ret += gen_rs_variants(name, ifcond, variants) + + ret += mcgen(''' + +%(cfg)s +#[derive(Clone, Debug)] +pub struct %(rs_name)s { +''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name)) + + if base: + if not base.is_implicit(): + ret += mcgen(''' + // Members inherited: +''', + c_name=base.c_name()) + base_members = base.members + if variants: + base_members = [m for m in base.members + if m.name != variants.tag_member.name] + ret += gen_struct_members(base_members) + if not base.is_implicit(): + ret += mcgen(''' + // Own members: +''') + + ret += gen_struct_members(members) + + if variants: + ret += mcgen(''' + pub u: %(rs_type)sVariant, +''', rs_type=rs_name(name)) + ret += mcgen(''' +} +''') + return ret + + +def gen_rs_enum(name: str, + ifcond: QAPISchemaIfCond, + members: List[QAPISchemaEnumMember]) -> str: + # append automatically generated _max value + enum_members = members + [QAPISchemaEnumMember('_MAX', None)] + + ret = mcgen(''' + +%(cfg)s +#[repr(u32)] +#[derive(Copy, Clone, Debug, PartialEq, Eq, qemu_api_macros::TryInto)] +pub enum %(rs_name)s { +''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name)) + + for member in enum_members: + ret += mcgen(''' + %(cfg)s + %(c_enum)s, +''', + cfg=member.ifcond.rsgen(), + c_enum=to_camel_case(rs_name(member.name))) + # picked the first, since that's what malloc0 does + # but arguably could use _MAX instead, or a qapi annotation + default = to_camel_case(rs_name(enum_members[0].name)) + ret += mcgen(''' +} + +%(cfg)s +impl Default for %(rs_name)s { + #[inline] + fn default() -> %(rs_name)s { + Self::%(default)s + } +} +''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name), + default=default) + return ret + + +def gen_rs_alternate(name: str, + ifcond: QAPISchemaIfCond, + variants: Optional[QAPISchemaVariants]) -> str: + if name in objects_seen: + return '' + + ret = '' + objects_seen.add(name) + + ret += mcgen(''' +%(cfg)s +#[derive(Clone, Debug)] +pub enum %(rs_name)s { +''', + cfg=ifcond.rsgen(), + rs_name=rs_name(name)) + + for var in variants.variants: + if var.type.name == 'q_empty': + continue + ret += mcgen(''' + %(cfg)s + %(mem_name)s(%(rs_type)s), +''', + cfg=var.ifcond.rsgen(), + rs_type=rs_type(var.type.c_unboxed_type(), ''), + mem_name=to_camel_case(rs_name(var.name))) + + ret += mcgen(''' +} +''') + return ret + + +class QAPISchemaGenRsTypeVisitor(QAPISchemaRsVisitor): + + def __init__(self, prefix: str) -> None: + super().__init__(prefix, 'qapi-types') + + def visit_begin(self, schema: QAPISchema) -> None: + # don't visit the empty type + objects_seen.add(schema.the_empty_object_type.name) + self._gen.preamble_add( + mcgen(''' +// generated by qapi-gen, DO NOT EDIT + +#![allow(non_camel_case_types)] + +use qemu_api::bindings::{QNull, QObject}; + +''')) + + def visit_object_type(self, + name: str, + info: Optional[QAPISourceInfo], + ifcond: QAPISchemaIfCond, + features: List[QAPISchemaFeature], + base: Optional[QAPISchemaObjectType], + members: List[QAPISchemaObjectTypeMember], + variants: Optional[QAPISchemaVariants]) -> None: + if name.startswith('q_'): + return + self._gen.add(gen_rs_object(name, ifcond, base, members, variants)) + + def visit_enum_type(self, + name: str, + info: Optional[QAPISourceInfo], + ifcond: QAPISchemaIfCond, + features: List[QAPISchemaFeature], + members: List[QAPISchemaEnumMember], + prefix: Optional[str]) -> None: + self._gen.add(gen_rs_enum(name, ifcond, members)) + + def visit_alternate_type(self, + name: str, + info: QAPISourceInfo, + ifcond: QAPISchemaIfCond, + features: List[QAPISchemaFeature], + variants: QAPISchemaVariants) -> None: + self._gen.add(gen_rs_alternate(name, ifcond, variants)) + + +def gen_rs_types(schema: QAPISchema, output_dir: str, prefix: str, builtins: bool) -> None: + # TODO: builtins? + vis = QAPISchemaGenRsTypeVisitor(prefix) + schema.visit(vis) + vis.write(output_dir) -- 2.49.0
