From 73df946d56c74384511a194dd01dbe099584fd1a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:14:23 +0200 Subject: Adding upstream version 1.16.10. Signed-off-by: Daniel Baumann --- src/net/rpc/jsonrpc/server.go | 134 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 src/net/rpc/jsonrpc/server.go (limited to 'src/net/rpc/jsonrpc/server.go') diff --git a/src/net/rpc/jsonrpc/server.go b/src/net/rpc/jsonrpc/server.go new file mode 100644 index 0000000..40e4e6f --- /dev/null +++ b/src/net/rpc/jsonrpc/server.go @@ -0,0 +1,134 @@ +// Copyright 2010 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package jsonrpc + +import ( + "encoding/json" + "errors" + "io" + "net/rpc" + "sync" +) + +var errMissingParams = errors.New("jsonrpc: request body missing params") + +type serverCodec struct { + dec *json.Decoder // for reading JSON values + enc *json.Encoder // for writing JSON values + c io.Closer + + // temporary work space + req serverRequest + + // JSON-RPC clients can use arbitrary json values as request IDs. + // Package rpc expects uint64 request IDs. + // We assign uint64 sequence numbers to incoming requests + // but save the original request ID in the pending map. + // When rpc responds, we use the sequence number in + // the response to find the original request ID. + mutex sync.Mutex // protects seq, pending + seq uint64 + pending map[uint64]*json.RawMessage +} + +// NewServerCodec returns a new rpc.ServerCodec using JSON-RPC on conn. +func NewServerCodec(conn io.ReadWriteCloser) rpc.ServerCodec { + return &serverCodec{ + dec: json.NewDecoder(conn), + enc: json.NewEncoder(conn), + c: conn, + pending: make(map[uint64]*json.RawMessage), + } +} + +type serverRequest struct { + Method string `json:"method"` + Params *json.RawMessage `json:"params"` + Id *json.RawMessage `json:"id"` +} + +func (r *serverRequest) reset() { + r.Method = "" + r.Params = nil + r.Id = nil +} + +type serverResponse struct { + Id *json.RawMessage `json:"id"` + Result interface{} `json:"result"` + Error interface{} `json:"error"` +} + +func (c *serverCodec) ReadRequestHeader(r *rpc.Request) error { + c.req.reset() + if err := c.dec.Decode(&c.req); err != nil { + return err + } + r.ServiceMethod = c.req.Method + + // JSON request id can be any JSON value; + // RPC package expects uint64. Translate to + // internal uint64 and save JSON on the side. + c.mutex.Lock() + c.seq++ + c.pending[c.seq] = c.req.Id + c.req.Id = nil + r.Seq = c.seq + c.mutex.Unlock() + + return nil +} + +func (c *serverCodec) ReadRequestBody(x interface{}) error { + if x == nil { + return nil + } + if c.req.Params == nil { + return errMissingParams + } + // JSON params is array value. + // RPC params is struct. + // Unmarshal into array containing struct for now. + // Should think about making RPC more general. + var params [1]interface{} + params[0] = x + return json.Unmarshal(*c.req.Params, ¶ms) +} + +var null = json.RawMessage([]byte("null")) + +func (c *serverCodec) WriteResponse(r *rpc.Response, x interface{}) error { + c.mutex.Lock() + b, ok := c.pending[r.Seq] + if !ok { + c.mutex.Unlock() + return errors.New("invalid sequence number in response") + } + delete(c.pending, r.Seq) + c.mutex.Unlock() + + if b == nil { + // Invalid request so no id. Use JSON null. + b = &null + } + resp := serverResponse{Id: b} + if r.Error == "" { + resp.Result = x + } else { + resp.Error = r.Error + } + return c.enc.Encode(resp) +} + +func (c *serverCodec) Close() error { + return c.c.Close() +} + +// ServeConn runs the JSON-RPC server on a single connection. +// ServeConn blocks, serving the connection until the client hangs up. +// The caller typically invokes ServeConn in a go statement. +func ServeConn(conn io.ReadWriteCloser) { + rpc.ServeCodec(NewServerCodec(conn)) +} -- cgit v1.2.3