Hi, In order to clean-up some hacks in qapi (having to unregister commands at runtime), I proposed a "[PATCH v5 02/20] qapi.py: add a simple #ifdef condition"
(see http://lists.gnu.org/archive/html/qemu-devel/2016-08/msg03106.html). However, we decided to drop that patch from the series and solve the problem later. The main issues were: - the syntax was awkward to the JSON schema and documentation - the evaluation of the condition was done in the qapi scripts, with very limited capability - each target/config would need different generated files. Instead, it could defer the #if evaluation to the C-preprocessor. With this series, top-level qapi JSON entity can take 'if' keys: { 'struct': 'TestIfStruct', 'data': { 'foo': 'int' }, 'if': 'defined(TEST_IF_STRUCT)' } Members can be exploded as dictionnary with 'type'/'if' keys: { 'struct': 'TestIfStruct', 'data': { 'foo': 'int', 'bar': { 'type': 'int', 'if': 'defined(TEST_IF_STRUCT_BAR)'} } } Enum values can be exploded as dictionnary with 'type'/'if' keys: { 'enum': 'TestIfEnum', 'data': [ 'foo', { 'name' : 'bar', 'if': 'defined(TEST_IF_ENUM_BAR)' } ] } A good benefit from having conditional schema is that introspection will reflect more accurately the capability of the server. Another benefit is that it may help to remove some dead code when disabling a functionality. Starting from patch "qapi: add conditions to VNC type/commands/events on the schema", the series demonstrate adding conditions, in order to remove qmp_unregister_commands_hack(). However, it feels like I cheated a little bit by using per-target NEED_CPU_H in the headers to avoid #define poison. The alternative could be to split the headers in common/target? There are a lot more things we could make conditional in the QAPI schema, like pci/kvm/xen/numa/vde/slirp/posix/win32/vsock/lzo etc etc, however I am still evaluating the implication of such changes both externally and internally, for those interested, I can share my wip branch. Comments welcome, Marc-André Lureau (26): qapi: fix type_seen key error qobject: replace dump_qobject() by qobject_to_string() qboject: add literal qobject type qapi: generate a literal qobject for introspection visitor: pass size of strings array to enum visitor qapi2texi: minor python code simplification qapi: add 'if' condition on top-level schema elements qapi: add 'if' condition on enum member values qapi: add 'if' condition on struct member qapi: add 'if' condition on union variant qapi: add 'if' condition on alternate variant qapi2texi: add 'If:' section to generated documentation qapi2texi: add 'If:' condition to enum values qapi2texi: add 'If:' condition to struct members qapi2texi: add condition to variants qapi: add conditions to VNC type/commands/events on the schema qapi: add conditions to SPICE type/commands/events on the schema qapi: add conditions to REPLICATION type/commands on the schema build-sys: move qapi variables in qapi.mak tests/qmp-test: add query-qmp-schema test build-sys: make qemu qapi objects per-target qapi: make rtc-reset-reinjection depend on TARGET_I386 qapi: make s390 commands depend on TARGET_S390X qapi: make query-gic-capabilities depend on TARGET_ARM qapi: make query-cpu-model-expansion depend on s390 or x86 qapi: make query-cpu-definitions depend on specific targets qapi-schema.json | 98 ++++++---- qapi/event.json | 21 +- include/qapi/visitor.h | 3 +- scripts/qapi.py | 232 ++++++++++++++++++----- scripts/qapi-commands.py | 4 +- scripts/qapi-event.py | 4 +- scripts/qapi-introspect.py | 116 +++++++----- scripts/qapi-types.py | 55 ++++-- scripts/qapi-visit.py | 29 ++- scripts/qapi2texi.py | 49 ++--- include/hw/qdev-core.h | 1 + include/qapi/qmp/qdict.h | 2 + include/qapi/qmp/qlist.h | 2 + include/qapi/qmp/qlit.h | 53 ++++++ include/qapi/qmp/qobject.h | 7 + include/qom/object.h | 4 + include/sysemu/arch_init.h | 11 -- qapi/qapi-visit-core.c | 23 +-- backends/hostmem.c | 1 + block/qapi.c | 90 +-------- crypto/secret.c | 1 + crypto/tlscreds.c | 1 + hmp.c | 14 +- hw/core/qdev-properties.c | 11 +- migration/colo.c | 14 +- monitor.c | 70 +------ net/filter.c | 1 + qmp.c | 72 +------ qobject/qdict.c | 30 +++ qobject/qlist.c | 23 +++ qobject/qlit.c | 53 ++++++ qobject/qobject.c | 21 ++ qom/object.c | 11 +- stubs/arch-query-cpu-def.c | 10 - stubs/arch-query-cpu-model-baseline.c | 12 -- stubs/arch-query-cpu-model-comparison.c | 12 -- stubs/arch-query-cpu-model-expansion.c | 12 -- stubs/qapi-event.c | 74 ++++++++ target/arm/helper.c | 3 +- target/i386/cpu.c | 5 +- target/ppc/translate_init.c | 3 +- target/s390x/cpu_models.c | 9 +- tests/check-qjson.c | 91 +++++---- tests/check-qlit.c | 52 +++++ tests/check-qom-proplist.c | 1 + tests/qmp-test.c | 21 ++ tests/test-qobject-input-visitor.c | 11 +- Makefile | 43 ++--- Makefile.objs | 9 +- Makefile.target | 4 + docs/devel/qapi-code-gen.txt | 29 ++- qapi.mak | 14 ++ qobject/Makefile.objs | 2 +- stubs/Makefile.objs | 5 +- tests/Makefile.include | 11 +- tests/qapi-schema/alternate-conflict-string.json | 4 +- tests/qapi-schema/alternate-dict-invalid.err | 1 + tests/qapi-schema/alternate-dict-invalid.exit | 1 + tests/qapi-schema/alternate-dict-invalid.json | 4 + tests/qapi-schema/alternate-dict-invalid.out | 0 tests/qapi-schema/bad-if.err | 1 + tests/qapi-schema/bad-if.exit | 1 + tests/qapi-schema/bad-if.json | 3 + tests/qapi-schema/bad-if.out | 0 tests/qapi-schema/enum-dict-member-invalid.err | 1 + tests/qapi-schema/enum-dict-member-invalid.exit | 1 + tests/qapi-schema/enum-dict-member-invalid.json | 2 + tests/qapi-schema/enum-dict-member-invalid.out | 0 tests/qapi-schema/enum-dict-member.err | 1 - tests/qapi-schema/enum-dict-member.exit | 2 +- tests/qapi-schema/enum-dict-member.json | 3 +- tests/qapi-schema/enum-dict-member.out | 4 + tests/qapi-schema/enum-if-invalid.err | 1 + tests/qapi-schema/enum-if-invalid.exit | 1 + tests/qapi-schema/enum-if-invalid.json | 3 + tests/qapi-schema/enum-if-invalid.out | 0 tests/qapi-schema/qapi-schema-test.json | 32 ++++ tests/qapi-schema/qapi-schema-test.out | 47 +++++ tests/qapi-schema/struct-if-invalid.err | 1 + tests/qapi-schema/struct-if-invalid.exit | 1 + tests/qapi-schema/struct-if-invalid.json | 3 + tests/qapi-schema/struct-if-invalid.out | 0 tests/qapi-schema/struct-member-type.err | 0 tests/qapi-schema/struct-member-type.exit | 1 + tests/qapi-schema/struct-member-type.json | 1 + tests/qapi-schema/struct-member-type.out | 5 + tests/qapi-schema/test-qapi.py | 31 ++- trace/Makefile.objs | 2 +- 88 files changed, 1094 insertions(+), 624 deletions(-) create mode 100644 include/qapi/qmp/qlit.h create mode 100644 qobject/qlit.c delete mode 100644 stubs/arch-query-cpu-def.c delete mode 100644 stubs/arch-query-cpu-model-baseline.c delete mode 100644 stubs/arch-query-cpu-model-comparison.c delete mode 100644 stubs/arch-query-cpu-model-expansion.c create mode 100644 stubs/qapi-event.c create mode 100644 tests/check-qlit.c create mode 100644 qapi.mak create mode 100644 tests/qapi-schema/alternate-dict-invalid.err create mode 100644 tests/qapi-schema/alternate-dict-invalid.exit create mode 100644 tests/qapi-schema/alternate-dict-invalid.json create mode 100644 tests/qapi-schema/alternate-dict-invalid.out create mode 100644 tests/qapi-schema/bad-if.err create mode 100644 tests/qapi-schema/bad-if.exit create mode 100644 tests/qapi-schema/bad-if.json create mode 100644 tests/qapi-schema/bad-if.out create mode 100644 tests/qapi-schema/enum-dict-member-invalid.err create mode 100644 tests/qapi-schema/enum-dict-member-invalid.exit create mode 100644 tests/qapi-schema/enum-dict-member-invalid.json create mode 100644 tests/qapi-schema/enum-dict-member-invalid.out create mode 100644 tests/qapi-schema/enum-if-invalid.err create mode 100644 tests/qapi-schema/enum-if-invalid.exit create mode 100644 tests/qapi-schema/enum-if-invalid.json create mode 100644 tests/qapi-schema/enum-if-invalid.out create mode 100644 tests/qapi-schema/struct-if-invalid.err create mode 100644 tests/qapi-schema/struct-if-invalid.exit create mode 100644 tests/qapi-schema/struct-if-invalid.json create mode 100644 tests/qapi-schema/struct-if-invalid.out create mode 100644 tests/qapi-schema/struct-member-type.err create mode 100644 tests/qapi-schema/struct-member-type.exit create mode 100644 tests/qapi-schema/struct-member-type.json create mode 100644 tests/qapi-schema/struct-member-type.out -- 2.14.0.rc0.1.g40ca67566
