rpc.h

#pragma once
#include "fmt.h"
#include "json.h"

// JSON-RPC request descriptor
struct mg_rpc_req {
  struct mg_rpc **head;  // RPC handlers list head
  struct mg_rpc *rpc;    // RPC handler being called
  mg_pfn_t pfn;          // Response printing function
  void *pfn_data;        // Response printing function data
  void *req_data;        // Arbitrary request data
  struct mg_str frame;   // Request, e.g. {"id":1,"method":"add","params":[1,2]}
};

// JSON-RPC method handler
struct mg_rpc {
  struct mg_rpc *next;              // Next in list
  struct mg_str method;             // Method pattern
  void (*fn)(struct mg_rpc_req *);  // Handler function
  void *fn_data;                    // Handler function argument
};

void mg_rpc_add(struct mg_rpc **head, struct mg_str method_pattern,
                void (*handler)(struct mg_rpc_req *), void *handler_data);
void mg_rpc_del(struct mg_rpc **head, void (*handler)(struct mg_rpc_req *));
void mg_rpc_process(struct mg_rpc_req *);

// Helper functions to print result or error frame
void mg_rpc_ok(struct mg_rpc_req *, const char *fmt, ...);
void mg_rpc_vok(struct mg_rpc_req *, const char *fmt, va_list *ap);
void mg_rpc_err(struct mg_rpc_req *, int code, const char *fmt, ...);
void mg_rpc_verr(struct mg_rpc_req *, int code, const char *fmt, va_list *);
void mg_rpc_list(struct mg_rpc_req *r);