github.com/matrixorigin/matrixone@v1.2.0/pkg/sql/colexec/connector/connector.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package connector
    16  
    17  import (
    18  	"bytes"
    19  
    20  	"github.com/matrixorigin/matrixone/pkg/container/batch"
    21  	"github.com/matrixorigin/matrixone/pkg/vm"
    22  	"github.com/matrixorigin/matrixone/pkg/vm/process"
    23  )
    24  
    25  const argName = "connector"
    26  
    27  func (arg *Argument) String(buf *bytes.Buffer) {
    28  	buf.WriteString(argName)
    29  	buf.WriteString(": pipe connector")
    30  }
    31  
    32  func (arg *Argument) Prepare(_ *process.Process) error {
    33  	return nil
    34  }
    35  
    36  func (arg *Argument) Call(proc *process.Process) (vm.CallResult, error) {
    37  	if err, isCancel := vm.CancelCheck(proc); isCancel {
    38  		return vm.CancelResult, err
    39  	}
    40  
    41  	reg := arg.Reg
    42  
    43  	result, err := arg.Children[0].Call(proc)
    44  	if err != nil {
    45  		return result, err
    46  	}
    47  
    48  	if result.Batch == nil {
    49  		result.Status = vm.ExecStop
    50  		return result, nil
    51  	}
    52  
    53  	bat := result.Batch
    54  	if bat.IsEmpty() {
    55  		result.Batch = batch.EmptyBatch
    56  		return result, nil
    57  	}
    58  	bat.AddCnt(1)
    59  
    60  	// there is no need to log anything here.
    61  	// because the context is already canceled means the pipeline closed normally.
    62  	select {
    63  	case <-proc.Ctx.Done():
    64  		proc.PutBatch(bat)
    65  		result.Status = vm.ExecStop
    66  		return result, nil
    67  
    68  	case <-reg.Ctx.Done():
    69  		proc.PutBatch(bat)
    70  		result.Status = vm.ExecStop
    71  		return result, nil
    72  
    73  	case reg.Ch <- bat:
    74  		return result, nil
    75  	}
    76  }