The C based gRPC (C++, Python, Ruby, Objective-C, PHP, C#) https://grpc.io/
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

702 lines
21 KiB

/*
*
* 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.
*
*/
#ifndef GRPCPP_IMPL_CODEGEN_CALL_H
#define GRPCPP_IMPL_CODEGEN_CALL_H
#include <assert.h>
#include <cstring>
#include <functional>
#include <map>
#include <memory>
#include <grpcpp/impl/codegen/byte_buffer.h>
#include <grpcpp/impl/codegen/call_hook.h>
#include <grpcpp/impl/codegen/client_context.h>
#include <grpcpp/impl/codegen/completion_queue_tag.h>
#include <grpcpp/impl/codegen/config.h>
#include <grpcpp/impl/codegen/core_codegen_interface.h>
#include <grpcpp/impl/codegen/serialization_traits.h>
#include <grpcpp/impl/codegen/slice.h>
#include <grpcpp/impl/codegen/status.h>
#include <grpcpp/impl/codegen/string_ref.h>
#include <grpc/impl/codegen/atm.h>
#include <grpc/impl/codegen/compression_types.h>
#include <grpc/impl/codegen/grpc_types.h>
namespace grpc {
class ByteBuffer;
class CompletionQueue;
extern CoreCodegenInterface* g_core_codegen_interface;
namespace internal {
class Call;
class CallHook;
// TODO(yangg) if the map is changed before we send, the pointers will be a
// mess. Make sure it does not happen.
inline grpc_metadata* FillMetadataArray(
const std::multimap<grpc::string, grpc::string>& metadata,
size_t* metadata_count, const grpc::string& optional_error_details) {
*metadata_count = metadata.size() + (optional_error_details.empty() ? 0 : 1);
if (*metadata_count == 0) {
return nullptr;
}
grpc_metadata* metadata_array =
(grpc_metadata*)(g_core_codegen_interface->gpr_malloc(
(*metadata_count) * sizeof(grpc_metadata)));
size_t i = 0;
for (auto iter = metadata.cbegin(); iter != metadata.cend(); ++iter, ++i) {
metadata_array[i].key = SliceReferencingString(iter->first);
metadata_array[i].value = SliceReferencingString(iter->second);
}
if (!optional_error_details.empty()) {
metadata_array[i].key =
g_core_codegen_interface->grpc_slice_from_static_buffer(
kBinaryErrorDetailsKey, sizeof(kBinaryErrorDetailsKey) - 1);
metadata_array[i].value = SliceReferencingString(optional_error_details);
}
return metadata_array;
}
} // namespace internal
/// Per-message write options.
class WriteOptions {
public:
WriteOptions() : flags_(0), last_message_(false) {}
WriteOptions(const WriteOptions& other)
: flags_(other.flags_), last_message_(other.last_message_) {}
/// Clear all flags.
inline void Clear() { flags_ = 0; }
/// Returns raw flags bitset.
inline uint32_t flags() const { return flags_; }
/// Sets flag for the disabling of compression for the next message write.
///
/// \sa GRPC_WRITE_NO_COMPRESS
inline WriteOptions& set_no_compression() {
SetBit(GRPC_WRITE_NO_COMPRESS);
return *this;
}
/// Clears flag for the disabling of compression for the next message write.
///
/// \sa GRPC_WRITE_NO_COMPRESS
inline WriteOptions& clear_no_compression() {
ClearBit(GRPC_WRITE_NO_COMPRESS);
return *this;
}
/// Get value for the flag indicating whether compression for the next
/// message write is forcefully disabled.
///
/// \sa GRPC_WRITE_NO_COMPRESS
inline bool get_no_compression() const {
return GetBit(GRPC_WRITE_NO_COMPRESS);
}
/// Sets flag indicating that the write may be buffered and need not go out on
/// the wire immediately.
///
/// \sa GRPC_WRITE_BUFFER_HINT
inline WriteOptions& set_buffer_hint() {
SetBit(GRPC_WRITE_BUFFER_HINT);
return *this;
}
/// Clears flag indicating that the write may be buffered and need not go out
/// on the wire immediately.
///
/// \sa GRPC_WRITE_BUFFER_HINT
inline WriteOptions& clear_buffer_hint() {
ClearBit(GRPC_WRITE_BUFFER_HINT);
return *this;
}
/// Get value for the flag indicating that the write may be buffered and need
/// not go out on the wire immediately.
///
/// \sa GRPC_WRITE_BUFFER_HINT
inline bool get_buffer_hint() const { return GetBit(GRPC_WRITE_BUFFER_HINT); }
/// corked bit: aliases set_buffer_hint currently, with the intent that
/// set_buffer_hint will be removed in the future
inline WriteOptions& set_corked() {
SetBit(GRPC_WRITE_BUFFER_HINT);
return *this;
}
inline WriteOptions& clear_corked() {
ClearBit(GRPC_WRITE_BUFFER_HINT);
return *this;
}
inline bool is_corked() const { return GetBit(GRPC_WRITE_BUFFER_HINT); }
/// last-message bit: indicates this is the last message in a stream
/// client-side: makes Write the equivalent of performing Write, WritesDone
/// in a single step
/// server-side: hold the Write until the service handler returns (sync api)
/// or until Finish is called (async api)
inline WriteOptions& set_last_message() {
last_message_ = true;
return *this;
}
/// Clears flag indicating that this is the last message in a stream,
/// disabling coalescing.
inline WriteOptions& clear_last_message() {
last_message_ = false;
return *this;
}
/// Guarantee that all bytes have been written to the socket before completing
/// this write (usually writes are completed when they pass flow control).
inline WriteOptions& set_write_through() {
SetBit(GRPC_WRITE_THROUGH);
return *this;
}
inline bool is_write_through() const { return GetBit(GRPC_WRITE_THROUGH); }
/// Get value for the flag indicating that this is the last message, and
/// should be coalesced with trailing metadata.
///
/// \sa GRPC_WRITE_LAST_MESSAGE
bool is_last_message() const { return last_message_; }
WriteOptions& operator=(const WriteOptions& rhs) {
flags_ = rhs.flags_;
return *this;
}
private:
void SetBit(const uint32_t mask) { flags_ |= mask; }
void ClearBit(const uint32_t mask) { flags_ &= ~mask; }
bool GetBit(const uint32_t mask) const { return (flags_ & mask) != 0; }
uint32_t flags_;
bool last_message_;
};
namespace internal {
/// Default argument for CallOpSet. I is unused by the class, but can be
/// used for generating multiple names for the same thing.
template <int I>
class CallNoOp {
protected:
void AddOp(grpc_op* ops, size_t* nops) {}
void FinishOp(bool* status) {}
};
class CallOpSendInitialMetadata {
public:
CallOpSendInitialMetadata() : send_(false) {
maybe_compression_level_.is_set = false;
}
void SendInitialMetadata(
const std::multimap<grpc::string, grpc::string>& metadata,
uint32_t flags) {
maybe_compression_level_.is_set = false;
send_ = true;
flags_ = flags;
initial_metadata_ =
FillMetadataArray(metadata, &initial_metadata_count_, "");
}
void set_compression_level(grpc_compression_level level) {
maybe_compression_level_.is_set = true;
maybe_compression_level_.level = level;
}
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (!send_) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_SEND_INITIAL_METADATA;
op->flags = flags_;
op->reserved = NULL;
op->data.send_initial_metadata.count = initial_metadata_count_;
op->data.send_initial_metadata.metadata = initial_metadata_;
op->data.send_initial_metadata.maybe_compression_level.is_set =
maybe_compression_level_.is_set;
if (maybe_compression_level_.is_set) {
op->data.send_initial_metadata.maybe_compression_level.level =
maybe_compression_level_.level;
}
}
void FinishOp(bool* status) {
if (!send_) return;
g_core_codegen_interface->gpr_free(initial_metadata_);
send_ = false;
}
bool send_;
uint32_t flags_;
size_t initial_metadata_count_;
grpc_metadata* initial_metadata_;
struct {
bool is_set;
grpc_compression_level level;
} maybe_compression_level_;
};
class CallOpSendMessage {
public:
CallOpSendMessage() : send_buf_() {}
/// Send \a message using \a options for the write. The \a options are cleared
/// after use.
template <class M>
Status SendMessage(const M& message,
WriteOptions options) GRPC_MUST_USE_RESULT;
template <class M>
Status SendMessage(const M& message) GRPC_MUST_USE_RESULT;
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (!send_buf_.Valid()) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_SEND_MESSAGE;
op->flags = write_options_.flags();
op->reserved = NULL;
op->data.send_message.send_message = send_buf_.c_buffer();
// Flags are per-message: clear them after use.
write_options_.Clear();
}
void FinishOp(bool* status) { send_buf_.Clear(); }
private:
ByteBuffer send_buf_;
WriteOptions write_options_;
};
template <class M>
Status CallOpSendMessage::SendMessage(const M& message, WriteOptions options) {
write_options_ = options;
bool own_buf;
// TODO(vjpai): Remove the void below when possible
// The void in the template parameter below should not be needed
// (since it should be implicit) but is needed due to an observed
// difference in behavior between clang and gcc for certain internal users
Status result = SerializationTraits<M, void>::Serialize(
message, send_buf_.bbuf_ptr(), &own_buf);
if (!own_buf) {
send_buf_.Duplicate();
}
return result;
}
template <class M>
Status CallOpSendMessage::SendMessage(const M& message) {
return SendMessage(message, WriteOptions());
}
template <class R>
class CallOpRecvMessage {
public:
CallOpRecvMessage()
: got_message(false),
message_(nullptr),
allow_not_getting_message_(false) {}
void RecvMessage(R* message) { message_ = message; }
// Do not change status if no message is received.
void AllowNoMessage() { allow_not_getting_message_ = true; }
bool got_message;
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (message_ == nullptr) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_RECV_MESSAGE;
op->flags = 0;
op->reserved = NULL;
op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
}
void FinishOp(bool* status) {
if (message_ == nullptr) return;
if (recv_buf_.Valid()) {
if (*status) {
got_message = *status =
SerializationTraits<R>::Deserialize(recv_buf_.bbuf_ptr(), message_)
.ok();
recv_buf_.Release();
} else {
got_message = false;
recv_buf_.Clear();
}
} else {
got_message = false;
if (!allow_not_getting_message_) {
*status = false;
}
}
message_ = nullptr;
}
private:
R* message_;
ByteBuffer recv_buf_;
bool allow_not_getting_message_;
};
class DeserializeFunc {
public:
virtual Status Deserialize(ByteBuffer* buf) = 0;
virtual ~DeserializeFunc() {}
};
template <class R>
class DeserializeFuncType final : public DeserializeFunc {
public:
DeserializeFuncType(R* message) : message_(message) {}
Status Deserialize(ByteBuffer* buf) override {
return SerializationTraits<R>::Deserialize(buf->bbuf_ptr(), message_);
}
~DeserializeFuncType() override {}
private:
R* message_; // Not a managed pointer because management is external to this
};
class CallOpGenericRecvMessage {
public:
CallOpGenericRecvMessage()
: got_message(false), allow_not_getting_message_(false) {}
template <class R>
void RecvMessage(R* message) {
// Use an explicit base class pointer to avoid resolution error in the
// following unique_ptr::reset for some old implementations.
DeserializeFunc* func = new DeserializeFuncType<R>(message);
deserialize_.reset(func);
}
// Do not change status if no message is received.
void AllowNoMessage() { allow_not_getting_message_ = true; }
bool got_message;
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (!deserialize_) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_RECV_MESSAGE;
op->flags = 0;
op->reserved = NULL;
op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
}
void FinishOp(bool* status) {
if (!deserialize_) return;
if (recv_buf_.Valid()) {
if (*status) {
got_message = true;
*status = deserialize_->Deserialize(&recv_buf_).ok();
recv_buf_.Release();
} else {
got_message = false;
recv_buf_.Clear();
}
} else {
got_message = false;
if (!allow_not_getting_message_) {
*status = false;
}
}
deserialize_.reset();
}
private:
std::unique_ptr<DeserializeFunc> deserialize_;
ByteBuffer recv_buf_;
bool allow_not_getting_message_;
};
class CallOpClientSendClose {
public:
CallOpClientSendClose() : send_(false) {}
void ClientSendClose() { send_ = true; }
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (!send_) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
op->flags = 0;
op->reserved = NULL;
}
void FinishOp(bool* status) { send_ = false; }
private:
bool send_;
};
class CallOpServerSendStatus {
public:
CallOpServerSendStatus() : send_status_available_(false) {}
void ServerSendStatus(
const std::multimap<grpc::string, grpc::string>& trailing_metadata,
const Status& status) {
send_error_details_ = status.error_details();
trailing_metadata_ = FillMetadataArray(
trailing_metadata, &trailing_metadata_count_, send_error_details_);
send_status_available_ = true;
send_status_code_ = static_cast<grpc_status_code>(status.error_code());
send_error_message_ = status.error_message();
}
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (!send_status_available_) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
op->data.send_status_from_server.trailing_metadata_count =
trailing_metadata_count_;
op->data.send_status_from_server.trailing_metadata = trailing_metadata_;
op->data.send_status_from_server.status = send_status_code_;
error_message_slice_ = SliceReferencingString(send_error_message_);
op->data.send_status_from_server.status_details =
send_error_message_.empty() ? nullptr : &error_message_slice_;
op->flags = 0;
op->reserved = NULL;
}
void FinishOp(bool* status) {
if (!send_status_available_) return;
g_core_codegen_interface->gpr_free(trailing_metadata_);
send_status_available_ = false;
}
private:
bool send_status_available_;
grpc_status_code send_status_code_;
grpc::string send_error_details_;
grpc::string send_error_message_;
size_t trailing_metadata_count_;
grpc_metadata* trailing_metadata_;
grpc_slice error_message_slice_;
};
class CallOpRecvInitialMetadata {
public:
CallOpRecvInitialMetadata() : metadata_map_(nullptr) {}
void RecvInitialMetadata(ClientContext* context) {
context->initial_metadata_received_ = true;
metadata_map_ = &context->recv_initial_metadata_;
}
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (metadata_map_ == nullptr) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_RECV_INITIAL_METADATA;
op->data.recv_initial_metadata.recv_initial_metadata = metadata_map_->arr();
op->flags = 0;
op->reserved = NULL;
}
void FinishOp(bool* status) {
if (metadata_map_ == nullptr) return;
metadata_map_ = nullptr;
}
private:
MetadataMap* metadata_map_;
};
class CallOpClientRecvStatus {
public:
CallOpClientRecvStatus()
: recv_status_(nullptr), debug_error_string_(nullptr) {}
void ClientRecvStatus(ClientContext* context, Status* status) {
client_context_ = context;
metadata_map_ = &client_context_->trailing_metadata_;
recv_status_ = status;
error_message_ = g_core_codegen_interface->grpc_empty_slice();
}
protected:
void AddOp(grpc_op* ops, size_t* nops) {
if (recv_status_ == nullptr) return;
grpc_op* op = &ops[(*nops)++];
op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
op->data.recv_status_on_client.trailing_metadata = metadata_map_->arr();
op->data.recv_status_on_client.status = &status_code_;
op->data.recv_status_on_client.status_details = &error_message_;
op->data.recv_status_on_client.error_string = &debug_error_string_;
op->flags = 0;
op->reserved = NULL;
}
void FinishOp(bool* status) {
if (recv_status_ == nullptr) return;
grpc::string binary_error_details = metadata_map_->GetBinaryErrorDetails();
*recv_status_ =
Status(static_cast<StatusCode>(status_code_),
GRPC_SLICE_IS_EMPTY(error_message_)
? grpc::string()
: grpc::string(GRPC_SLICE_START_PTR(error_message_),
GRPC_SLICE_END_PTR(error_message_)),
binary_error_details);
client_context_->set_debug_error_string(
debug_error_string_ != nullptr ? debug_error_string_ : "");
g_core_codegen_interface->grpc_slice_unref(error_message_);
if (debug_error_string_ != nullptr) {
g_core_codegen_interface->gpr_free((void*)debug_error_string_);
}
recv_status_ = nullptr;
}
private:
ClientContext* client_context_;
MetadataMap* metadata_map_;
Status* recv_status_;
const char* debug_error_string_;
grpc_status_code status_code_;
grpc_slice error_message_;
};
/// An abstract collection of call ops, used to generate the
/// grpc_call_op structure to pass down to the lower layers,
/// and as it is-a CompletionQueueTag, also massages the final
/// completion into the correct form for consumption in the C++
/// API.
class CallOpSetInterface : public CompletionQueueTag {
public:
/// Fills in grpc_op, starting from ops[*nops] and moving
/// upwards.
virtual void FillOps(grpc_call* call, grpc_op* ops, size_t* nops) = 0;
/// Get the tag to be used at the core completion queue. Generally, the
/// value of cq_tag will be "this". However, it can be overridden if we
/// want core to process the tag differently (e.g., as a core callback)
virtual void* cq_tag() = 0;
};
/// Primary implementation of CallOpSetInterface.
/// Since we cannot use variadic templates, we declare slots up to
/// the maximum count of ops we'll need in a set. We leverage the
/// empty base class optimization to slim this class (especially
/// when there are many unused slots used). To avoid duplicate base classes,
/// the template parmeter for CallNoOp is varied by argument position.
template <class Op1 = CallNoOp<1>, class Op2 = CallNoOp<2>,
class Op3 = CallNoOp<3>, class Op4 = CallNoOp<4>,
class Op5 = CallNoOp<5>, class Op6 = CallNoOp<6>>
class CallOpSet : public CallOpSetInterface,
public Op1,
public Op2,
public Op3,
public Op4,
public Op5,
public Op6 {
public:
CallOpSet() : cq_tag_(this), return_tag_(this), call_(nullptr) {}
void FillOps(grpc_call* call, grpc_op* ops, size_t* nops) override {
this->Op1::AddOp(ops, nops);
this->Op2::AddOp(ops, nops);
this->Op3::AddOp(ops, nops);
this->Op4::AddOp(ops, nops);
this->Op5::AddOp(ops, nops);
this->Op6::AddOp(ops, nops);
g_core_codegen_interface->grpc_call_ref(call);
call_ = call;
}
bool FinalizeResult(void** tag, bool* status) override {
this->Op1::FinishOp(status);
this->Op2::FinishOp(status);
this->Op3::FinishOp(status);
this->Op4::FinishOp(status);
this->Op5::FinishOp(status);
this->Op6::FinishOp(status);
*tag = return_tag_;
g_core_codegen_interface->grpc_call_unref(call_);
return true;
}
void set_output_tag(void* return_tag) { return_tag_ = return_tag; }
void* cq_tag() override { return cq_tag_; }
/// set_cq_tag is used to provide a different core CQ tag than "this".
/// This is used for callback-based tags, where the core tag is the core
/// callback function. It does not change the use or behavior of any other
/// function (such as FinalizeResult)
void set_cq_tag(void* cq_tag) { cq_tag_ = cq_tag; }
private:
void* cq_tag_;
void* return_tag_;
grpc_call* call_;
};
/// Straightforward wrapping of the C call object
class Call final {
public:
/** call is owned by the caller */
Call(grpc_call* call, CallHook* call_hook, CompletionQueue* cq)
: call_hook_(call_hook),
cq_(cq),
call_(call),
max_receive_message_size_(-1) {}
Call(grpc_call* call, CallHook* call_hook, CompletionQueue* cq,
int max_receive_message_size)
: call_hook_(call_hook),
cq_(cq),
call_(call),
max_receive_message_size_(max_receive_message_size) {}
void PerformOps(CallOpSetInterface* ops) {
call_hook_->PerformOpsOnCall(ops, this);
}
grpc_call* call() const { return call_; }
CompletionQueue* cq() const { return cq_; }
int max_receive_message_size() const { return max_receive_message_size_; }
private:
CallHook* call_hook_;
CompletionQueue* cq_;
grpc_call* call_;
int max_receive_message_size_;
};
} // namespace internal
} // namespace grpc
#endif // GRPCPP_IMPL_CODEGEN_CALL_H