1 //
2 //
3 // Copyright 2015 gRPC authors.
4 //
5 // Licensed under the Apache License, Version 2.0 (the "License");
6 // you may not use this file except in compliance with the License.
7 // You may obtain a copy of the License at
8 //
9 //     http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing, software
12 // distributed under the License is distributed on an "AS IS" BASIS,
13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 // See the License for the specific language governing permissions and
15 // limitations under the License.
16 //
17 //
18 
19 #ifndef GRPC_SRC_CORE_LIB_IOMGR_POLLING_ENTITY_H
20 #define GRPC_SRC_CORE_LIB_IOMGR_POLLING_ENTITY_H
21 
22 #include <grpc/support/port_platform.h>
23 
24 #include "src/core/lib/iomgr/pollset.h"
25 #include "src/core/lib/iomgr/pollset_set.h"
26 #include "src/core/lib/promise/context.h"
27 
28 typedef enum grpc_pollset_tag {
29   GRPC_POLLS_NONE,
30   GRPC_POLLS_POLLSET,
31   GRPC_POLLS_POLLSET_SET
32 } grpc_pollset_tag;
33 
34 // A grpc_polling_entity is a pollset-or-pollset_set container. It allows
35 // functions that accept a pollset XOR a pollset_set to do so through an
36 // abstract interface. No ownership is taken.
37 
38 struct grpc_polling_entity {
39   union {
40     grpc_pollset* pollset = nullptr;
41     grpc_pollset_set* pollset_set;
42   } pollent;
43   grpc_pollset_tag tag = GRPC_POLLS_NONE;
44 };
45 
46 grpc_polling_entity grpc_polling_entity_create_from_pollset_set(
47     grpc_pollset_set* pollset_set);
48 grpc_polling_entity grpc_polling_entity_create_from_pollset(
49     grpc_pollset* pollset);
50 
51 /// If \a pollent contains a pollset, return it. Otherwise, return NULL
52 grpc_pollset* grpc_polling_entity_pollset(grpc_polling_entity* pollent);
53 
54 /// If \a pollent contains a pollset_set, return it. Otherwise, return NULL
55 grpc_pollset_set* grpc_polling_entity_pollset_set(grpc_polling_entity* pollent);
56 
57 bool grpc_polling_entity_is_empty(const grpc_polling_entity* pollent);
58 
59 /// Add the pollset or pollset_set in \a pollent to the destination pollset_set
60 ///\a * pss_dst
61 void grpc_polling_entity_add_to_pollset_set(grpc_polling_entity* pollent,
62                                             grpc_pollset_set* pss_dst);
63 
64 /// Delete the pollset or pollset_set in \a pollent from the destination
65 /// pollset_set \a * pss_dst
66 void grpc_polling_entity_del_from_pollset_set(grpc_polling_entity* pollent,
67                                               grpc_pollset_set* pss_dst);
68 
69 namespace grpc_core {
70 template <>
71 struct ContextType<grpc_polling_entity> {};
72 }  // namespace grpc_core
73 
74 #endif  // GRPC_SRC_CORE_LIB_IOMGR_POLLING_ENTITY_H
75