It's been more than a month... Looking for reviews of the qapi-gen changes, especially the non-Rust-specific parts.
Paolo Il gio 8 gen 2026, 14:10 Paolo Bonzini <[email protected]> ha scritto: > This adds two related parts of the Rust bindings: > > - QAPI code generator that creates Rust structs from the JSON > description. The structs are *not* ABI compatible with the > C ones, instead they use native Rust data types. > > - QObject bindings and (de)serialization support, which can be used to > convert QObjects to and from QAPI structs. > > Unfortunately Rust code is not able to use visitors, other than by > creating an intermediate QObject. This is because of the different > architecture of serde vs. QAPI visitors, and because visitor's > dual-purpose functions, where the same function is used by both input and > output visitors, rely heavily on the structs using the same representation > as the visitor arguments (for example NUL-terminated strings). > > The serde format implementation was co-authored by me and Marc-André. > Marc-André did all the bug fixing and integration testing. > > As an example of how this would be used, the marshaling functions for > QMP commands would look like this: > > fn qmp_marshal_query_stats(args: *mut QDict, > retp: *mut *mut QObject, errp: *mut *mut Error) > { > let qobj = unsafe { QObject::cloned_from_raw(args.cast()) }; > > let result = from_qobject::<StatsFilter>(qobj) > .map_err(anyhow::Error::from) > .and_then(qmp_query_stats) > .and_then(|ret| > to_qobject::<Vec<StatsResult>>(ret).map_err(anyhow::Error::from)); > > match qmp_marshal_query_stats_rs(qobj) { > Ok(ret) => unsafe { *retp = ret.into_raw(); }, > Err(e) => unsafe { crate::Error::from(e).propagate(errp) }, > } > } > > Despite the long v1->v2, the changes are mostly cosmetic; there are a few > small differences in the detection of types to be wrapped with Box<>, > because Vec<> is now considered to break cycles. > > Available at branch rust-next of https://gitlab.com/bonzini/qemu (which > is now almost empty other than this series, yay). > > Paolo > > v1->v2, Rust: > - adjust comments in C code (include/qobject/qobject.h) > - improve or fix documentation in rust/util/src/qobject/mod.rs > - introduce a qobject! macro that is equivalent to QOBJECT() > - remark when functions are converted from C inlines > - rename from_int/from_uint/from_double macros > - fix incorrect "native: true" on serde and serde_core overrides > - rebase > > qapi-gen: > - rewrite QAPISchemaIfCond.rsgen() to avoid messy typing > - new patches 10-11 to extend existing qapigen code > - rewritten rs_type() to avoid going through a C type first > - removed renaming of QAPICBackend > - reused C functions for case conversions > - clean up rs_name, move it to common.py (needed for rs_type() changes) > - Vec<> can break cycles and avoid boxing of structs > - restrict squashing of consecutive newlines to Rust code > - add copyright blurb > - annotate that using a separate qapi-gen backend is temporary > - drop #[derive(common::TryInto)] from enums > > Marc-André Lureau (7): > rust/qobject: add Display/Debug > scripts/qapi: add QAPISchemaIfCond.rsgen() > scripts/qapi: generate high-level Rust bindings > scripts/rustc_args: add --no-strict-cfg > rust/util: build QAPI types > scripts/qapi: add serde attributes > rust/tests: QAPI integration tests > > Paolo Bonzini (9): > rust/qobject: add basic bindings > subprojects: add serde > rust/qobject: add Serialize implementation > rust/qobject: add Serializer (to_qobject) implementation > rust/qobject: add Deserialize implementation > rust/qobject: add Deserializer (from_qobject) implementation > rust/qobject: add from/to JSON bindings for QObject > scripts/qapi: add QAPISchemaType.is_predefined > scripts/qapi: pull c_name from camel_to_upper to caller > > docs/devel/rust.rst | 1 + > meson.build | 4 +- > include/qobject/qobject.h | 5 +- > rust/util/wrapper.h | 8 + > qapi/meson.build | 9 + > rust/Cargo.lock | 2 + > rust/Cargo.toml | 2 + > rust/meson.build | 4 + > rust/tests/meson.build | 21 +- > rust/tests/tests/integration.rs | 2 + > rust/tests/tests/qapi.rs | 444 +++++++++++++ > rust/util/Cargo.toml | 2 + > rust/util/meson.build | 30 +- > rust/util/src/lib.rs | 4 + > rust/util/src/qobject/deserialize.rs | 134 ++++ > rust/util/src/qobject/deserializer.rs | 371 +++++++++++ > rust/util/src/qobject/error.rs | 58 ++ > rust/util/src/qobject/mod.rs | 383 ++++++++++++ > rust/util/src/qobject/serialize.rs | 59 ++ > rust/util/src/qobject/serializer.rs | 585 ++++++++++++++++++ > scripts/archive-source.sh | 3 + > scripts/make-release | 2 +- > scripts/qapi/backend.py | 25 + > scripts/qapi/common.py | 66 +- > scripts/qapi/rs.py | 61 ++ > scripts/qapi/rs_types.py | 394 ++++++++++++ > scripts/qapi/schema.py | 74 ++- > scripts/rust/rustc_args.py | 16 +- > subprojects/.gitignore | 3 + > .../packagefiles/serde-1-rs/meson.build | 36 ++ > .../packagefiles/serde-1.0.226-include.patch | 16 + > .../packagefiles/serde_core-1-rs/meson.build | 25 + > .../serde_core-1.0.226-include.patch | 15 + > .../serde_derive-1-rs/meson.build | 35 ++ > .../serde_derive-1.0.226-include.patch | 11 + > subprojects/serde-1-rs.wrap | 11 + > subprojects/serde_core-1-rs.wrap | 11 + > subprojects/serde_derive-1-rs.wrap | 11 + > 38 files changed, 2910 insertions(+), 33 deletions(-) > create mode 100644 rust/tests/tests/integration.rs > create mode 100644 rust/tests/tests/qapi.rs > create mode 100644 rust/util/src/qobject/deserialize.rs > create mode 100644 rust/util/src/qobject/deserializer.rs > create mode 100644 rust/util/src/qobject/error.rs > create mode 100644 rust/util/src/qobject/mod.rs > create mode 100644 rust/util/src/qobject/serialize.rs > create mode 100644 rust/util/src/qobject/serializer.rs > create mode 100644 scripts/qapi/rs.py > create mode 100644 scripts/qapi/rs_types.py > create mode 100644 subprojects/packagefiles/serde-1-rs/meson.build > create mode 100644 subprojects/packagefiles/serde-1.0.226-include.patch > create mode 100644 subprojects/packagefiles/serde_core-1-rs/meson.build > create mode 100644 > subprojects/packagefiles/serde_core-1.0.226-include.patch > create mode 100644 subprojects/packagefiles/serde_derive-1-rs/meson.build > create mode 100644 > subprojects/packagefiles/serde_derive-1.0.226-include.patch > create mode 100644 subprojects/serde-1-rs.wrap > create mode 100644 subprojects/serde_core-1-rs.wrap > create mode 100644 subprojects/serde_derive-1-rs.wrap > > -- > 2.52.0 >
