diff options
Diffstat (limited to 'scripts/qapi/visit.py')
| -rw-r--r-- | scripts/qapi/visit.py | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/scripts/qapi/visit.py b/scripts/qapi/visit.py new file mode 100644 index 0000000000..3ed78165d7 --- /dev/null +++ b/scripts/qapi/visit.py @@ -0,0 +1,353 @@ +""" +QAPI visitor generator + +Copyright IBM, Corp. 2011 +Copyright (C) 2014-2018 Red Hat, Inc. + +Authors: + Anthony Liguori <aliguori@us.ibm.com> + Michael Roth <mdroth@linux.vnet.ibm.com> + Markus Armbruster <armbru@redhat.com> + +This work is licensed under the terms of the GNU GPL, version 2. +See the COPYING file in the top-level directory. +""" + +from qapi.common import * + + +def gen_visit_decl(name, scalar=False): + c_type = c_name(name) + ' *' + if not scalar: + c_type += '*' + return mcgen(''' +void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error **errp); +''', + c_name=c_name(name), c_type=c_type) + + +def gen_visit_members_decl(name): + return mcgen(''' + +void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp); +''', + c_name=c_name(name)) + + +def gen_visit_object_members(name, base, members, variants): + ret = mcgen(''' + +void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) +{ + Error *err = NULL; + +''', + c_name=c_name(name)) + + if base: + ret += mcgen(''' + visit_type_%(c_type)s_members(v, (%(c_type)s *)obj, &err); + if (err) { + goto out; + } +''', + c_type=base.c_name()) + + for memb in members: + if memb.optional: + ret += mcgen(''' + if (visit_optional(v, "%(name)s", &obj->has_%(c_name)s)) { +''', + name=memb.name, c_name=c_name(memb.name)) + push_indent() + ret += mcgen(''' + visit_type_%(c_type)s(v, "%(name)s", &obj->%(c_name)s, &err); + if (err) { + goto out; + } +''', + c_type=memb.type.c_name(), name=memb.name, + c_name=c_name(memb.name)) + if memb.optional: + pop_indent() + ret += mcgen(''' + } +''') + + if variants: + ret += mcgen(''' + switch (obj->%(c_name)s) { +''', + c_name=c_name(variants.tag_member.name)) + + for var in variants.variants: + ret += mcgen(''' + case %(case)s: + visit_type_%(c_type)s_members(v, &obj->u.%(c_name)s, &err); + break; +''', + case=c_enum_const(variants.tag_member.type.name, + var.name, + variants.tag_member.type.prefix), + c_type=var.type.c_name(), c_name=c_name(var.name)) + + ret += mcgen(''' + default: + abort(); + } +''') + + # 'goto out' produced for base, for each member, and if variants were + # present + if base or members or variants: + ret += mcgen(''' + +out: +''') + ret += mcgen(''' + error_propagate(errp, err); +} +''') + return ret + + +def gen_visit_list(name, element_type): + return mcgen(''' + +void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +{ + Error *err = NULL; + %(c_name)s *tail; + size_t size = sizeof(**obj); + + visit_start_list(v, name, (GenericList **)obj, size, &err); + if (err) { + goto out; + } + + for (tail = *obj; tail; + tail = (%(c_name)s *)visit_next_list(v, (GenericList *)tail, size)) { + visit_type_%(c_elt_type)s(v, NULL, &tail->value, &err); + if (err) { + break; + } + } + + if (!err) { + visit_check_list(v, &err); + } + visit_end_list(v, (void **)obj); + if (err && visit_is_input(v)) { + qapi_free_%(c_name)s(*obj); + *obj = NULL; + } +out: + error_propagate(errp, err); +} +''', + c_name=c_name(name), c_elt_type=element_type.c_name()) + + +def gen_visit_enum(name): + return mcgen(''' + +void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error **errp) +{ + int value = *obj; + visit_type_enum(v, name, &value, &%(c_name)s_lookup, errp); + *obj = value; +} +''', + c_name=c_name(name)) + + +def gen_visit_alternate(name, variants): + ret = mcgen(''' + +void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +{ + Error *err = NULL; + + visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj), + &err); + if (err) { + goto out; + } + if (!*obj) { + goto out_obj; + } + switch ((*obj)->type) { +''', + c_name=c_name(name)) + + for var in variants.variants: + ret += mcgen(''' + case %(case)s: +''', + case=var.type.alternate_qtype()) + if isinstance(var.type, QAPISchemaObjectType): + ret += mcgen(''' + visit_start_struct(v, name, NULL, 0, &err); + if (err) { + break; + } + visit_type_%(c_type)s_members(v, &(*obj)->u.%(c_name)s, &err); + if (!err) { + visit_check_struct(v, &err); + } + visit_end_struct(v, NULL); +''', + c_type=var.type.c_name(), + c_name=c_name(var.name)) + else: + ret += mcgen(''' + visit_type_%(c_type)s(v, name, &(*obj)->u.%(c_name)s, &err); +''', + c_type=var.type.c_name(), + c_name=c_name(var.name)) + ret += mcgen(''' + break; +''') + + ret += mcgen(''' + case QTYPE_NONE: + abort(); + default: + error_setg(&err, QERR_INVALID_PARAMETER_TYPE, name ? name : "null", + "%(name)s"); + } +out_obj: + visit_end_alternate(v, (void **)obj); + if (err && visit_is_input(v)) { + qapi_free_%(c_name)s(*obj); + *obj = NULL; + } +out: + error_propagate(errp, err); +} +''', + name=name, c_name=c_name(name)) + + return ret + + +def gen_visit_object(name, base, members, variants): + return mcgen(''' + +void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +{ + Error *err = NULL; + + visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), &err); + if (err) { + goto out; + } + if (!*obj) { + goto out_obj; + } + visit_type_%(c_name)s_members(v, *obj, &err); + if (err) { + goto out_obj; + } + visit_check_struct(v, &err); +out_obj: + visit_end_struct(v, (void **)obj); + if (err && visit_is_input(v)) { + qapi_free_%(c_name)s(*obj); + *obj = NULL; + } +out: + error_propagate(errp, err); +} +''', + c_name=c_name(name)) + + +class QAPISchemaGenVisitVisitor(QAPISchemaVisitor): + def __init__(self, opt_builtins): + self._opt_builtins = opt_builtins + self.decl = None + self.defn = None + self._btin = None + + def visit_begin(self, schema): + self.decl = '' + self.defn = '' + self._btin = '\n' + guardstart('QAPI_VISIT_BUILTIN') + + def visit_end(self): + # To avoid header dependency hell, we always generate + # declarations for built-in types in our header files and + # simply guard them. See also opt_builtins (command line + # option -b). + self._btin += guardend('QAPI_VISIT_BUILTIN') + self.decl = self._btin + self.decl + self._btin = None + + def visit_enum_type(self, name, info, values, prefix): + # Special case for our lone builtin enum type + # TODO use something cleaner than existence of info + if not info: + self._btin += gen_visit_decl(name, scalar=True) + if self._opt_builtins: + self.defn += gen_visit_enum(name) + else: + self.decl += gen_visit_decl(name, scalar=True) + self.defn += gen_visit_enum(name) + + def visit_array_type(self, name, info, element_type): + decl = gen_visit_decl(name) + defn = gen_visit_list(name, element_type) + if isinstance(element_type, QAPISchemaBuiltinType): + self._btin += decl + if self._opt_builtins: + self.defn += defn + else: + self.decl += decl + self.defn += defn + + def visit_object_type(self, name, info, base, members, variants): + # Nothing to do for the special empty builtin + if name == 'q_empty': + return + self.decl += gen_visit_members_decl(name) + self.defn += gen_visit_object_members(name, base, members, variants) + # TODO Worth changing the visitor signature, so we could + # directly use rather than repeat type.is_implicit()? + if not name.startswith('q_'): + # only explicit types need an allocating visit + self.decl += gen_visit_decl(name) + self.defn += gen_visit_object(name, base, members, variants) + + def visit_alternate_type(self, name, info, variants): + self.decl += gen_visit_decl(name) + self.defn += gen_visit_alternate(name, variants) + + +def gen_visit(schema, output_dir, prefix, opt_builtins): + blurb = ' * Schema-defined QAPI visitors' + genc = QAPIGenC(blurb, __doc__) + genh = QAPIGenH(blurb, __doc__) + + genc.add(mcgen(''' +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "qapi/error.h" +#include "qapi/qmp/qerror.h" +#include "%(prefix)sqapi-visit.h" +''', + prefix=prefix)) + + genh.add(mcgen(''' +#include "qapi/visitor.h" +#include "%(prefix)sqapi-types.h" + +''', + prefix=prefix)) + + vis = QAPISchemaGenVisitVisitor(opt_builtins) + schema.visit(vis) + genc.add(vis.defn) + genh.add(vis.decl) + genc.write(output_dir, prefix + 'qapi-visit.c') + genh.write(output_dir, prefix + 'qapi-visit.h') |