Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2022-01-27-v2' into staging

QAPI patches patches for 2022-01-27

# gpg: Signature made Thu 27 Jan 2022 14:19:51 GMT
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2022-01-27-v2:
  qapi: generate trace events by default
  meson: document why we don't generate trace events for tests/ and qga/
  docs/qapi-code-gen: update to cover trace events code generation
  meson: generate trace events for qmp commands
  qapi/commands: Optionally generate trace for QMP commands
  qapi/commands: refactor error handling code
  qapi/gen: Add FOO.trace-events output module
  schemas: add missing vim modeline

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 27 insertions, 4 deletions

diff --git a/scripts/qapi/gen.py b/scripts/qapi/gen.py
index 995a97d2b8..113b49134d 100644
--- a/scripts/qapi/gen.py
+++ b/scripts/qapi/gen.py
@@ -192,6 +192,11 @@ class QAPIGenH(QAPIGenC):
         return guardend(self.fname)
 
 
+class QAPIGenTrace(QAPIGen):
+    def _top(self) -> str:
+        return super()._top() + '# AUTOMATICALLY GENERATED, DO NOT MODIFY\n\n'
+
+
 @contextmanager
 def ifcontext(ifcond: QAPISchemaIfCond, *args: QAPIGenCCode) -> Iterator[None]:
     """
@@ -244,15 +249,18 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
                  what: str,
                  user_blurb: str,
                  builtin_blurb: Optional[str],
-                 pydoc: str):
+                 pydoc: str,
+                 gen_tracing: bool = False):
         self._prefix = prefix
         self._what = what
         self._user_blurb = user_blurb
         self._builtin_blurb = builtin_blurb
         self._pydoc = pydoc
         self._current_module: Optional[str] = None
-        self._module: Dict[str, Tuple[QAPIGenC, QAPIGenH]] = {}
+        self._module: Dict[str, Tuple[QAPIGenC, QAPIGenH,
+                                      Optional[QAPIGenTrace]]] = {}
         self._main_module: Optional[str] = None
+        self._gen_tracing = gen_tracing
 
     @property
     def _genc(self) -> QAPIGenC:
@@ -264,6 +272,14 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
         assert self._current_module is not None
         return self._module[self._current_module][1]
 
+    @property
+    def _gen_trace_events(self) -> QAPIGenTrace:
+        assert self._gen_tracing
+        assert self._current_module is not None
+        gent = self._module[self._current_module][2]
+        assert gent is not None
+        return gent
+
     @staticmethod
     def _module_dirname(name: str) -> str:
         if QAPISchemaModule.is_user_module(name):
@@ -293,7 +309,12 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
         basename = self._module_filename(self._what, name)
         genc = QAPIGenC(basename + '.c', blurb, self._pydoc)
         genh = QAPIGenH(basename + '.h', blurb, self._pydoc)
-        self._module[name] = (genc, genh)
+
+        gent: Optional[QAPIGenTrace] = None
+        if self._gen_tracing:
+            gent = QAPIGenTrace(basename + '.trace-events')
+
+        self._module[name] = (genc, genh, gent)
         self._current_module = name
 
     @contextmanager
@@ -304,11 +325,13 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
         self._current_module = old_module
 
     def write(self, output_dir: str, opt_builtins: bool = False) -> None:
-        for name, (genc, genh) in self._module.items():
+        for name, (genc, genh, gent) in self._module.items():
             if QAPISchemaModule.is_builtin_module(name) and not opt_builtins:
                 continue
             genc.write(output_dir)
             genh.write(output_dir)
+            if gent is not None:
+                gent.write(output_dir)
 
     def _begin_builtin_module(self) -> None:
         pass