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_CORE_LIB_SURFACE_CHANNEL_H
20 #define GRPC_CORE_LIB_SURFACE_CHANNEL_H
21
22 #include <grpc/support/port_platform.h>
23
24 #include <map>
25
26 #include "src/core/lib/channel/channel_stack.h"
27 #include "src/core/lib/channel/channel_stack_builder.h"
28 #include "src/core/lib/channel/channelz.h"
29 #include "src/core/lib/gprpp/manual_constructor.h"
30 #include "src/core/lib/surface/channel_stack_type.h"
31 #include "src/core/lib/transport/metadata.h"
32
33 grpc_channel* grpc_channel_create(const char* target,
34 const grpc_channel_args* args,
35 grpc_channel_stack_type channel_stack_type,
36 grpc_transport* optional_transport,
37 grpc_resource_user* resource_user = nullptr);
38
39 /** The same as grpc_channel_destroy, but doesn't create an ExecCtx, and so
40 * is safe to use from within core. */
41 void grpc_channel_destroy_internal(grpc_channel* channel);
42
43 grpc_channel* grpc_channel_create_with_builder(
44 grpc_channel_stack_builder* builder,
45 grpc_channel_stack_type channel_stack_type);
46
47 /** Create a call given a grpc_channel, in order to call \a method.
48 Progress is tied to activity on \a pollset_set. The returned call object is
49 meant to be used with \a grpc_call_start_batch_and_execute, which relies on
50 callbacks to signal completions. \a method and \a host need
51 only live through the invocation of this function. If \a parent_call is
52 non-NULL, it must be a server-side call. It will be used to propagate
53 properties from the server call to this new client call, depending on the
54 value of \a propagation_mask (see propagation_bits.h for possible values) */
55 grpc_call* grpc_channel_create_pollset_set_call(
56 grpc_channel* channel, grpc_call* parent_call, uint32_t propagation_mask,
57 grpc_pollset_set* pollset_set, const grpc_slice& method,
58 const grpc_slice* host, grpc_millis deadline, void* reserved);
59
60 /** Get a (borrowed) pointer to this channels underlying channel stack */
61 grpc_channel_stack* grpc_channel_get_channel_stack(grpc_channel* channel);
62
63 grpc_core::channelz::ChannelNode* grpc_channel_get_channelz_node(
64 grpc_channel* channel);
65
66 size_t grpc_channel_get_call_size_estimate(grpc_channel* channel);
67 void grpc_channel_update_call_size_estimate(grpc_channel* channel, size_t size);
68
69 namespace grpc_core {
70
71 struct RegisteredCall {
72 grpc_mdelem path;
73 grpc_mdelem authority;
74
75 explicit RegisteredCall(const char* method, const char* host);
76 // TODO(vjpai): delete copy constructor once all supported compilers allow
77 // std::map value_type to be MoveConstructible.
78 RegisteredCall(const RegisteredCall& other);
79 RegisteredCall(RegisteredCall&& other) noexcept;
80
81 ~RegisteredCall();
82 };
83
84 struct CallRegistrationTable {
85 grpc_core::Mutex mu;
86 std::map<std::pair<const char*, const char*>, RegisteredCall>
87 map /* GUARDED_BY(mu) */;
88 int method_registration_attempts /* GUARDED_BY(mu) */ = 0;
89 };
90
91 } // namespace grpc_core
92
93 struct grpc_channel {
94 int is_client;
95 grpc_compression_options compression_options;
96
97 gpr_atm call_size_estimate;
98 grpc_resource_user* resource_user;
99
100 // TODO(vjpai): Once the grpc_channel is allocated via new rather than malloc,
101 // expand the members of the CallRegistrationTable directly into
102 // the grpc_channel. For now it is kept separate so that all the
103 // manual constructing can be done with a single call rather than
104 // a separate manual construction for each field.
105 grpc_core::ManualConstructor<grpc_core::CallRegistrationTable>
106 registration_table;
107 grpc_core::RefCountedPtr<grpc_core::channelz::ChannelNode> channelz_node;
108
109 char* target;
110 };
111 #define CHANNEL_STACK_FROM_CHANNEL(c) ((grpc_channel_stack*)((c) + 1))
112
grpc_channel_compression_options(const grpc_channel * channel)113 inline grpc_compression_options grpc_channel_compression_options(
114 const grpc_channel* channel) {
115 return channel->compression_options;
116 }
117
grpc_channel_get_channel_stack(grpc_channel * channel)118 inline grpc_channel_stack* grpc_channel_get_channel_stack(
119 grpc_channel* channel) {
120 return CHANNEL_STACK_FROM_CHANNEL(channel);
121 }
122
grpc_channel_get_channelz_node(grpc_channel * channel)123 inline grpc_core::channelz::ChannelNode* grpc_channel_get_channelz_node(
124 grpc_channel* channel) {
125 return channel->channelz_node.get();
126 }
127
128 #ifndef NDEBUG
grpc_channel_internal_ref(grpc_channel * channel,const char * reason)129 inline void grpc_channel_internal_ref(grpc_channel* channel,
130 const char* reason) {
131 GRPC_CHANNEL_STACK_REF(CHANNEL_STACK_FROM_CHANNEL(channel), reason);
132 }
grpc_channel_internal_unref(grpc_channel * channel,const char * reason)133 inline void grpc_channel_internal_unref(grpc_channel* channel,
134 const char* reason) {
135 GRPC_CHANNEL_STACK_UNREF(CHANNEL_STACK_FROM_CHANNEL(channel), reason);
136 }
137 #define GRPC_CHANNEL_INTERNAL_REF(channel, reason) \
138 grpc_channel_internal_ref(channel, reason)
139 #define GRPC_CHANNEL_INTERNAL_UNREF(channel, reason) \
140 grpc_channel_internal_unref(channel, reason)
141 #else
grpc_channel_internal_ref(grpc_channel * channel)142 inline void grpc_channel_internal_ref(grpc_channel* channel) {
143 GRPC_CHANNEL_STACK_REF(CHANNEL_STACK_FROM_CHANNEL(channel), "unused");
144 }
grpc_channel_internal_unref(grpc_channel * channel)145 inline void grpc_channel_internal_unref(grpc_channel* channel) {
146 GRPC_CHANNEL_STACK_UNREF(CHANNEL_STACK_FROM_CHANNEL(channel), "unused");
147 }
148 #define GRPC_CHANNEL_INTERNAL_REF(channel, reason) \
149 grpc_channel_internal_ref(channel)
150 #define GRPC_CHANNEL_INTERNAL_UNREF(channel, reason) \
151 grpc_channel_internal_unref(channel)
152 #endif
153
154 /** Return the channel's compression options. */
155 grpc_compression_options grpc_channel_compression_options(
156 const grpc_channel* channel);
157
158 #endif /* GRPC_CORE_LIB_SURFACE_CHANNEL_H */
159