small tweaks

rpc_util.go

@@ -22,7 +22,6 @@
 	"compress/gzip"
 	"context"
 	"encoding/binary"
-	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -809,8 +808,6 @@
 	}
 }
 
-var errMaxMessageSizeExceeded = errors.New("max message size exceeded")
-
 // recvAndDecompress reads a message from the stream, decompressing it if necessary.
 //
 // Cancelling the returned cancel function releases the buffer back to the pool. So the caller should cancel as soon as
@@ -852,24 +849,25 @@
 	return out, nil
 }
 
-// Using compressor, decompress d, returning data and size.
-// If the decompressed data exceeds maxReceiveMessageSize, it returns errMaxMessageSizeExceeded.
+// decompress decompresses the given data `d` using either a custom decompressor `dc`
+// or a provided `compressor`. It checks if the decompressed data exceeds the
+// `maxReceiveMessageSize` and returns an error if so.
 func decompress(compressor encoding.Compressor, d mem.BufferSlice, dc Decompressor, maxReceiveMessageSize int, pool mem.BufferPool) (mem.BufferSlice, error) {
 	if dc != nil {
 		uncompressed, err := dc.Do(d.Reader())
 		if err != nil {
 			return nil, status.Errorf(codes.Internal, "grpc: failed to decompress the received message: %v", err)
 		}
 		if len(uncompressed) > maxReceiveMessageSize {
 			return nil, status.Errorf(codes.ResourceExhausted, "grpc: message after decompression larger than max (%d vs. %d)", len(uncompressed), maxReceiveMessageSize)
 		}
 		return mem.BufferSlice{mem.SliceBuffer(uncompressed)}, nil
 	}
 	if compressor != nil {
 		dcReader, err := compressor.Decompress(d.Reader())
 		if err != nil {
 			return nil, status.Errorf(codes.Internal, "grpc: failed to decompress the message: %v", err)
 		}
 
 		out, err := mem.ReadAll(io.LimitReader(dcReader, int64(maxReceiveMessageSize)), pool)
 		if err != nil {
@@ -884,7 +882,7 @@
 		}
 		return out, nil
 	}
 	return d, nil
 }
 
 // doesReceiveMessageOverflow checks if the number of bytes read from the stream