1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
|
/*
*
* Copyright 2015 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#include <grpcpp/channel.h>
#include <cstring>
#include <memory>
#include <grpc/grpc.h>
#include <grpc/slice.h>
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/sync.h>
#include <grpc/support/time.h>
#include <grpcpp/client_context.h>
#include <grpcpp/completion_queue.h>
#include <grpcpp/impl/call.h>
#include <grpcpp/impl/codegen/call_op_set.h>
#include <grpcpp/impl/codegen/completion_queue_tag.h>
#include <grpcpp/impl/grpc_library.h>
#include <grpcpp/impl/rpc_method.h>
#include <grpcpp/security/credentials.h>
#include <grpcpp/support/channel_arguments.h>
#include <grpcpp/support/config.h>
#include <grpcpp/support/status.h>
#include "src/core/lib/gpr/string.h"
#include "src/core/lib/surface/completion_queue.h"
namespace grpc {
static ::grpc::internal::GrpcLibraryInitializer g_gli_initializer;
Channel::Channel(const TString& host, grpc_channel* channel,
std::vector<std::unique_ptr<
::grpc::experimental::ClientInterceptorFactoryInterface>>
interceptor_creators)
: host_(host), c_channel_(channel) {
interceptor_creators_ = std::move(interceptor_creators);
g_gli_initializer.summon();
}
Channel::~Channel() {
grpc_channel_destroy(c_channel_);
if (callback_cq_ != nullptr) {
callback_cq_->Shutdown();
}
}
namespace {
inline grpc_slice SliceFromArray(const char* arr, size_t len) {
return g_core_codegen_interface->grpc_slice_from_copied_buffer(arr, len);
}
TString GetChannelInfoField(grpc_channel* channel,
grpc_channel_info* channel_info,
char*** channel_info_field) {
char* value = nullptr;
memset(channel_info, 0, sizeof(*channel_info));
*channel_info_field = &value;
grpc_channel_get_info(channel, channel_info);
if (value == nullptr) return "";
TString result = value;
gpr_free(value);
return result;
}
} // namespace
TString Channel::GetLoadBalancingPolicyName() const {
grpc_channel_info channel_info;
return GetChannelInfoField(c_channel_, &channel_info,
&channel_info.lb_policy_name);
}
TString Channel::GetServiceConfigJSON() const {
grpc_channel_info channel_info;
return GetChannelInfoField(c_channel_, &channel_info,
&channel_info.service_config_json);
}
namespace experimental {
void ChannelResetConnectionBackoff(Channel* channel) {
grpc_channel_reset_connect_backoff(channel->c_channel_);
}
} // namespace experimental
::grpc::internal::Call Channel::CreateCallInternal(
const ::grpc::internal::RpcMethod& method, ::grpc::ClientContext* context,
::grpc::CompletionQueue* cq, size_t interceptor_pos) {
const bool kRegistered = method.channel_tag() && context->authority().empty();
grpc_call* c_call = nullptr;
if (kRegistered) {
c_call = grpc_channel_create_registered_call(
c_channel_, context->propagate_from_call_,
context->propagation_options_.c_bitmask(), cq->cq(),
method.channel_tag(), context->raw_deadline(), nullptr);
} else {
const ::TString* host_str = nullptr;
if (!context->authority_.empty()) {
host_str = &context->authority_;
} else if (!host_.empty()) {
host_str = &host_;
}
grpc_slice method_slice =
SliceFromArray(method.name(), strlen(method.name()));
grpc_slice host_slice;
if (host_str != nullptr) {
host_slice = ::grpc::SliceFromCopiedString(*host_str);
}
c_call = grpc_channel_create_call(
c_channel_, context->propagate_from_call_,
context->propagation_options_.c_bitmask(), cq->cq(), method_slice,
host_str == nullptr ? nullptr : &host_slice, context->raw_deadline(),
nullptr);
grpc_slice_unref(method_slice);
if (host_str != nullptr) {
grpc_slice_unref(host_slice);
}
}
grpc_census_call_set_context(c_call, context->census_context());
// ClientRpcInfo should be set before call because set_call also checks
// whether the call has been cancelled, and if the call was cancelled, we
// should notify the interceptors too.
auto* info =
context->set_client_rpc_info(method.name(), method.method_type(), this,
interceptor_creators_, interceptor_pos);
context->set_call(c_call, shared_from_this());
return ::grpc::internal::Call(c_call, this, cq, info);
}
::grpc::internal::Call Channel::CreateCall(
const ::grpc::internal::RpcMethod& method, ::grpc::ClientContext* context,
CompletionQueue* cq) {
return CreateCallInternal(method, context, cq, 0);
}
void Channel::PerformOpsOnCall(::grpc::internal::CallOpSetInterface* ops,
::grpc::internal::Call* call) {
ops->FillOps(
call); // Make a copy of call. It's fine since Call just has pointers
}
void* Channel::RegisterMethod(const char* method) {
return grpc_channel_register_call(
c_channel_, method, host_.empty() ? nullptr : host_.c_str(), nullptr);
}
grpc_connectivity_state Channel::GetState(bool try_to_connect) {
return grpc_channel_check_connectivity_state(c_channel_, try_to_connect);
}
namespace {
class TagSaver final : public ::grpc::internal::CompletionQueueTag {
public:
explicit TagSaver(void* tag) : tag_(tag) {}
~TagSaver() override {}
bool FinalizeResult(void** tag, bool* /*status*/) override {
*tag = tag_;
delete this;
return true;
}
private:
void* tag_;
};
} // namespace
void Channel::NotifyOnStateChangeImpl(grpc_connectivity_state last_observed,
gpr_timespec deadline,
::grpc::CompletionQueue* cq, void* tag) {
TagSaver* tag_saver = new TagSaver(tag);
grpc_channel_watch_connectivity_state(c_channel_, last_observed, deadline,
cq->cq(), tag_saver);
}
bool Channel::WaitForStateChangeImpl(grpc_connectivity_state last_observed,
gpr_timespec deadline) {
::grpc::CompletionQueue cq;
bool ok = false;
void* tag = nullptr;
NotifyOnStateChangeImpl(last_observed, deadline, &cq, nullptr);
cq.Next(&tag, &ok);
GPR_ASSERT(tag == nullptr);
return ok;
}
namespace {
class ShutdownCallback : public grpc_experimental_completion_queue_functor {
public:
ShutdownCallback() {
functor_run = &ShutdownCallback::Run;
// Set inlineable to true since this callback is trivial and thus does not
// need to be run from the executor (triggering a thread hop). This should
// only be used by internal callbacks like this and not by user application
// code.
inlineable = true;
}
// TakeCQ takes ownership of the cq into the shutdown callback
// so that the shutdown callback will be responsible for destroying it
void TakeCQ(::grpc::CompletionQueue* cq) { cq_ = cq; }
// The Run function will get invoked by the completion queue library
// when the shutdown is actually complete
static void Run(grpc_experimental_completion_queue_functor* cb, int) {
auto* callback = static_cast<ShutdownCallback*>(cb);
delete callback->cq_;
delete callback;
}
private:
::grpc::CompletionQueue* cq_ = nullptr;
};
} // namespace
::grpc::CompletionQueue* Channel::CallbackCQ() {
// TODO(vjpai): Consider using a single global CQ for the default CQ
// if there is no explicit per-channel CQ registered
grpc::internal::MutexLock l(&mu_);
if (callback_cq_ == nullptr) {
auto* shutdown_callback = new ShutdownCallback;
callback_cq_ = new ::grpc::CompletionQueue(grpc_completion_queue_attributes{
GRPC_CQ_CURRENT_VERSION, GRPC_CQ_CALLBACK, GRPC_CQ_DEFAULT_POLLING,
shutdown_callback});
// Transfer ownership of the new cq to its own shutdown callback
shutdown_callback->TakeCQ(callback_cq_);
}
return callback_cq_;
}
} // namespace grpc
|
