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+/*
+ * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu>
+ * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef EVENT2_RPC_H_INCLUDED_
+#define EVENT2_RPC_H_INCLUDED_
+
+/* For int types. */
+#include <event2/util.h>
+#include <event2/visibility.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** @file rpc.h
+ *
+ * This header files provides basic support for an RPC server and client.
+ *
+ * To support RPCs in a server, every supported RPC command needs to be
+ * defined and registered.
+ *
+ * EVRPC_HEADER(SendCommand, Request, Reply);
+ *
+ * SendCommand is the name of the RPC command.
+ * Request is the name of a structure generated by event_rpcgen.py.
+ * It contains all parameters relating to the SendCommand RPC. The
+ * server needs to fill in the Reply structure.
+ * Reply is the name of a structure generated by event_rpcgen.py. It
+ * contains the answer to the RPC.
+ *
+ * To register an RPC with an HTTP server, you need to first create an RPC
+ * base with:
+ *
+ * struct evrpc_base *base = evrpc_init(http);
+ *
+ * A specific RPC can then be registered with
+ *
+ * EVRPC_REGISTER(base, SendCommand, Request, Reply, FunctionCB, arg);
+ *
+ * when the server receives an appropriately formatted RPC, the user callback
+ * is invoked. The callback needs to fill in the reply structure.
+ *
+ * void FunctionCB(EVRPC_STRUCT(SendCommand)* rpc, void *arg);
+ *
+ * To send the reply, call EVRPC_REQUEST_DONE(rpc);
+ *
+ * See the regression test for an example.
+ */
+
+/**
+ Determines if the member has been set in the message
+
+ @param msg the message to inspect
+ @param member the member variable to test for presences
+ @return 1 if it's present or 0 otherwise.
+*/
+#define EVTAG_HAS(msg, member) \
+ ((msg)->member##_set == 1)
+
+#ifndef EVENT2_RPC_COMPAT_H_INCLUDED_
+
+/**
+ Assigns a value to the member in the message.
+
+ @param msg the message to which to assign a value
+ @param member the name of the member variable
+ @param value the value to assign
+*/
+#define EVTAG_ASSIGN(msg, member, value) \
+ (*(msg)->base->member##_assign)((msg), (value))
+/**
+ Assigns a value to the member in the message.
+
+ @param msg the message to which to assign a value
+ @param member the name of the member variable
+ @param value the value to assign
+ @param len the length of the value
+*/
+#define EVTAG_ASSIGN_WITH_LEN(msg, member, value, len) \
+ (*(msg)->base->member##_assign)((msg), (value), (len))
+/**
+ Returns the value for a member.
+
+ @param msg the message from which to get the value
+ @param member the name of the member variable
+ @param pvalue a pointer to the variable to hold the value
+ @return 0 on success, -1 otherwise.
+*/
+#define EVTAG_GET(msg, member, pvalue) \
+ (*(msg)->base->member##_get)((msg), (pvalue))
+/**
+ Returns the value for a member.
+
+ @param msg the message from which to get the value
+ @param member the name of the member variable
+ @param pvalue a pointer to the variable to hold the value
+ @param plen a pointer to the length of the value
+ @return 0 on success, -1 otherwise.
+*/
+#define EVTAG_GET_WITH_LEN(msg, member, pvalue, plen) \
+ (*(msg)->base->member##_get)((msg), (pvalue), (plen))
+
+#endif /* EVENT2_RPC_COMPAT_H_INCLUDED_ */
+
+/**
+ Adds a value to an array.
+*/
+#define EVTAG_ARRAY_ADD_VALUE(msg, member, value) \
+ (*(msg)->base->member##_add)((msg), (value))
+/**
+ Allocates a new entry in the array and returns it.
+*/
+#define EVTAG_ARRAY_ADD(msg, member) \
+ (*(msg)->base->member##_add)(msg)
+/**
+ Gets a variable at the specified offset from the array.
+*/
+#define EVTAG_ARRAY_GET(msg, member, offset, pvalue) \
+ (*(msg)->base->member##_get)((msg), (offset), (pvalue))
+/**
+ Returns the number of entries in the array.
+*/
+#define EVTAG_ARRAY_LEN(msg, member) ((msg)->member##_length)
+
+
+struct evbuffer;
+struct event_base;
+struct evrpc_req_generic;
+struct evrpc_request_wrapper;
+struct evrpc;
+
+/** The type of a specific RPC Message
+ *
+ * @param rpcname the name of the RPC message
+ */
+#define EVRPC_STRUCT(rpcname) struct evrpc_req__##rpcname
+
+struct evhttp_request;
+struct evrpc_status;
+struct evrpc_hook_meta;
+
+/** Creates the definitions and prototypes for an RPC
+ *
+ * You need to use EVRPC_HEADER to create structures and function prototypes
+ * needed by the server and client implementation. The structures have to be
+ * defined in an .rpc file and converted to source code via event_rpcgen.py
+ *
+ * @param rpcname the name of the RPC
+ * @param reqstruct the name of the RPC request structure
+ * @param replystruct the name of the RPC reply structure
+ * @see EVRPC_GENERATE()
+ */
+#define EVRPC_HEADER(rpcname, reqstruct, rplystruct) \
+EVRPC_STRUCT(rpcname) { \
+ struct evrpc_hook_meta *hook_meta; \
+ struct reqstruct* request; \
+ struct rplystruct* reply; \
+ struct evrpc* rpc; \
+ struct evhttp_request* http_req; \
+ struct evbuffer* rpc_data; \
+}; \
+EVENT2_EXPORT_SYMBOL \
+int evrpc_send_request_##rpcname(struct evrpc_pool *, \
+ struct reqstruct *, struct rplystruct *, \
+ void (*)(struct evrpc_status *, \
+ struct reqstruct *, struct rplystruct *, void *cbarg), \
+ void *);
+
+struct evrpc_pool;
+
+/** use EVRPC_GENERATE instead */
+EVENT2_EXPORT_SYMBOL
+struct evrpc_request_wrapper *evrpc_make_request_ctx(
+ struct evrpc_pool *pool, void *request, void *reply,
+ const char *rpcname,
+ void (*req_marshal)(struct evbuffer*, void *),
+ void (*rpl_clear)(void *),
+ int (*rpl_unmarshal)(void *, struct evbuffer *),
+ void (*cb)(struct evrpc_status *, void *, void *, void *),
+ void *cbarg);
+
+/** Creates a context structure that contains rpc specific information.
+ *
+ * EVRPC_MAKE_CTX is used to populate a RPC specific context that
+ * contains information about marshaling the RPC data types.
+ *
+ * @param rpcname the name of the RPC
+ * @param reqstruct the name of the RPC request structure
+ * @param replystruct the name of the RPC reply structure
+ * @param pool the evrpc_pool over which to make the request
+ * @param request a pointer to the RPC request structure object
+ * @param reply a pointer to the RPC reply structure object
+ * @param cb the callback function to call when the RPC has completed
+ * @param cbarg the argument to supply to the callback
+ */
+#define EVRPC_MAKE_CTX(rpcname, reqstruct, rplystruct, \
+ pool, request, reply, cb, cbarg) \
+ evrpc_make_request_ctx(pool, request, reply, \
+ #rpcname, \
+ (void (*)(struct evbuffer *, void *))reqstruct##_marshal, \
+ (void (*)(void *))rplystruct##_clear, \
+ (int (*)(void *, struct evbuffer *))rplystruct##_unmarshal, \
+ (void (*)(struct evrpc_status *, void *, void *, void *))cb, \
+ cbarg)
+
+/** Generates the code for receiving and sending an RPC message
+ *
+ * EVRPC_GENERATE is used to create the code corresponding to sending
+ * and receiving a particular RPC message
+ *
+ * @param rpcname the name of the RPC
+ * @param reqstruct the name of the RPC request structure
+ * @param replystruct the name of the RPC reply structure
+ * @see EVRPC_HEADER()
+ */
+#define EVRPC_GENERATE(rpcname, reqstruct, rplystruct) \
+ int evrpc_send_request_##rpcname(struct evrpc_pool *pool, \
+ struct reqstruct *request, struct rplystruct *reply, \
+ void (*cb)(struct evrpc_status *, \
+ struct reqstruct *, struct rplystruct *, void *cbarg), \
+ void *cbarg) { \
+ return evrpc_send_request_generic(pool, request, reply, \
+ (void (*)(struct evrpc_status *, void *, void *, void *))cb, \
+ cbarg, \
+ #rpcname, \
+ (void (*)(struct evbuffer *, void *))reqstruct##_marshal, \
+ (void (*)(void *))rplystruct##_clear, \
+ (int (*)(void *, struct evbuffer *))rplystruct##_unmarshal); \
+}
+
+/** Provides access to the HTTP request object underlying an RPC
+ *
+ * Access to the underlying http object; can be used to look at headers or
+ * for getting the remote ip address
+ *
+ * @param rpc_req the rpc request structure provided to the server callback
+ * @return an struct evhttp_request object that can be inspected for
+ * HTTP headers or sender information.
+ */
+#define EVRPC_REQUEST_HTTP(rpc_req) (rpc_req)->http_req
+
+/** completes the server response to an rpc request */
+EVENT2_EXPORT_SYMBOL
+void evrpc_request_done(struct evrpc_req_generic *req);
+
+/** accessors for request and reply */
+EVENT2_EXPORT_SYMBOL
+void *evrpc_get_request(struct evrpc_req_generic *req);
+EVENT2_EXPORT_SYMBOL
+void *evrpc_get_reply(struct evrpc_req_generic *req);
+
+/** Creates the reply to an RPC request
+ *
+ * EVRPC_REQUEST_DONE is used to answer a request; the reply is expected
+ * to have been filled in. The request and reply pointers become invalid
+ * after this call has finished.
+ *
+ * @param rpc_req the rpc request structure provided to the server callback
+ */
+#define EVRPC_REQUEST_DONE(rpc_req) do { \
+ struct evrpc_req_generic *req_ = (struct evrpc_req_generic *)(rpc_req); \
+ evrpc_request_done(req_); \
+} while (0)
+
+
+struct evrpc_base;
+struct evhttp;
+
+/* functions to start up the rpc system */
+
+/** Creates a new rpc base from which RPC requests can be received
+ *
+ * @param server a pointer to an existing HTTP server
+ * @return a newly allocated evrpc_base struct or NULL if an error occurred
+ * @see evrpc_free()
+ */
+EVENT2_EXPORT_SYMBOL
+struct evrpc_base *evrpc_init(struct evhttp *server);
+
+/**
+ * Frees the evrpc base
+ *
+ * For now, you are responsible for making sure that no rpcs are ongoing.
+ *
+ * @param base the evrpc_base object to be freed
+ * @see evrpc_init
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_free(struct evrpc_base *base);
+
+/** register RPCs with the HTTP Server
+ *
+ * registers a new RPC with the HTTP server, each RPC needs to have
+ * a unique name under which it can be identified.
+ *
+ * @param base the evrpc_base structure in which the RPC should be
+ * registered.
+ * @param name the name of the RPC
+ * @param request the name of the RPC request structure
+ * @param reply the name of the RPC reply structure
+ * @param callback the callback that should be invoked when the RPC
+ * is received. The callback has the following prototype
+ * void (*callback)(EVRPC_STRUCT(Message)* rpc, void *arg)
+ * @param cbarg an additional parameter that can be passed to the callback.
+ * The parameter can be used to carry around state.
+ */
+#define EVRPC_REGISTER(base, name, request, reply, callback, cbarg) \
+ evrpc_register_generic(base, #name, \
+ (void (*)(struct evrpc_req_generic *, void *))callback, cbarg, \
+ (void *(*)(void *))request##_new_with_arg, NULL, \
+ (void (*)(void *))request##_free, \
+ (int (*)(void *, struct evbuffer *))request##_unmarshal, \
+ (void *(*)(void *))reply##_new_with_arg, NULL, \
+ (void (*)(void *))reply##_free, \
+ (int (*)(void *))reply##_complete, \
+ (void (*)(struct evbuffer *, void *))reply##_marshal)
+
+/**
+ Low level function for registering an RPC with a server.
+
+ Use EVRPC_REGISTER() instead.
+
+ @see EVRPC_REGISTER()
+*/
+EVENT2_EXPORT_SYMBOL
+int evrpc_register_rpc(struct evrpc_base *, struct evrpc *,
+ void (*)(struct evrpc_req_generic*, void *), void *);
+
+/**
+ * Unregisters an already registered RPC
+ *
+ * @param base the evrpc_base object from which to unregister an RPC
+ * @param name the name of the rpc to unregister
+ * @return -1 on error or 0 when successful.
+ * @see EVRPC_REGISTER()
+ */
+#define EVRPC_UNREGISTER(base, name) evrpc_unregister_rpc((base), #name)
+
+EVENT2_EXPORT_SYMBOL
+int evrpc_unregister_rpc(struct evrpc_base *base, const char *name);
+
+/*
+ * Client-side RPC support
+ */
+
+struct evhttp_connection;
+struct evrpc_status;
+
+/** launches an RPC and sends it to the server
+ *
+ * EVRPC_MAKE_REQUEST() is used by the client to send an RPC to the server.
+ *
+ * @param name the name of the RPC
+ * @param pool the evrpc_pool that contains the connection objects over which
+ * the request should be sent.
+ * @param request a pointer to the RPC request structure - it contains the
+ * data to be sent to the server.
+ * @param reply a pointer to the RPC reply structure. It is going to be filled
+ * if the request was answered successfully
+ * @param cb the callback to invoke when the RPC request has been answered
+ * @param cbarg an additional argument to be passed to the client
+ * @return 0 on success, -1 on failure
+ */
+#define EVRPC_MAKE_REQUEST(name, pool, request, reply, cb, cbarg) \
+ evrpc_send_request_##name((pool), (request), (reply), (cb), (cbarg))
+
+/**
+ Makes an RPC request based on the provided context.
+
+ This is a low-level function and should not be used directly
+ unless a custom context object is provided. Use EVRPC_MAKE_REQUEST()
+ instead.
+
+ @param ctx a context from EVRPC_MAKE_CTX()
+ @returns 0 on success, -1 otherwise.
+ @see EVRPC_MAKE_REQUEST(), EVRPC_MAKE_CTX()
+*/
+EVENT2_EXPORT_SYMBOL
+int evrpc_make_request(struct evrpc_request_wrapper *ctx);
+
+/** creates an rpc connection pool
+ *
+ * a pool has a number of connections associated with it.
+ * rpc requests are always made via a pool.
+ *
+ * @param base a pointer to an struct event_based object; can be left NULL
+ * in singled-threaded applications
+ * @return a newly allocated struct evrpc_pool object or NULL if an error
+ * occurred
+ * @see evrpc_pool_free()
+ */
+EVENT2_EXPORT_SYMBOL
+struct evrpc_pool *evrpc_pool_new(struct event_base *base);
+/** frees an rpc connection pool
+ *
+ * @param pool a pointer to an evrpc_pool allocated via evrpc_pool_new()
+ * @see evrpc_pool_new()
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_pool_free(struct evrpc_pool *pool);
+
+/**
+ * Adds a connection over which rpc can be dispatched to the pool.
+ *
+ * The connection object must have been newly created.
+ *
+ * @param pool the pool to which to add the connection
+ * @param evcon the connection to add to the pool.
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_pool_add_connection(struct evrpc_pool *pool,
+ struct evhttp_connection *evcon);
+
+/**
+ * Removes a connection from the pool.
+ *
+ * The connection object must have been newly created.
+ *
+ * @param pool the pool from which to remove the connection
+ * @param evcon the connection to remove from the pool.
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_pool_remove_connection(struct evrpc_pool *pool,
+ struct evhttp_connection *evcon);
+
+/**
+ * Sets the timeout in secs after which a request has to complete. The
+ * RPC is completely aborted if it does not complete by then. Setting
+ * the timeout to 0 means that it never timeouts and can be used to
+ * implement callback type RPCs.
+ *
+ * Any connection already in the pool will be updated with the new
+ * timeout. Connections added to the pool after set_timeout has be
+ * called receive the pool timeout only if no timeout has been set
+ * for the connection itself.
+ *
+ * @param pool a pointer to a struct evrpc_pool object
+ * @param timeout_in_secs the number of seconds after which a request should
+ * timeout and a failure be returned to the callback.
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_pool_set_timeout(struct evrpc_pool *pool, int timeout_in_secs);
+
+/**
+ * Hooks for changing the input and output of RPCs; this can be used to
+ * implement compression, authentication, encryption, ...
+ */
+
+enum EVRPC_HOOK_TYPE {
+ EVRPC_INPUT, /**< apply the function to an input hook */
+ EVRPC_OUTPUT /**< apply the function to an output hook */
+};
+
+#ifndef _WIN32
+/** Deprecated alias for EVRPC_INPUT. Not available on windows, where it
+ * conflicts with platform headers. */
+#define INPUT EVRPC_INPUT
+/** Deprecated alias for EVRPC_OUTPUT. Not available on windows, where it
+ * conflicts with platform headers. */
+#define OUTPUT EVRPC_OUTPUT
+#endif
+
+/**
+ * Return value from hook processing functions
+ */
+
+enum EVRPC_HOOK_RESULT {
+ EVRPC_TERMINATE = -1, /**< indicates the rpc should be terminated */
+ EVRPC_CONTINUE = 0, /**< continue processing the rpc */
+ EVRPC_PAUSE = 1 /**< pause processing request until resumed */
+};
+
+/** adds a processing hook to either an rpc base or rpc pool
+ *
+ * If a hook returns TERMINATE, the processing is aborted. On CONTINUE,
+ * the request is immediately processed after the hook returns. If the
+ * hook returns PAUSE, request processing stops until evrpc_resume_request()
+ * has been called.
+ *
+ * The add functions return handles that can be used for removing hooks.
+ *
+ * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool
+ * @param hook_type either INPUT or OUTPUT
+ * @param cb the callback to call when the hook is activated
+ * @param cb_arg an additional argument for the callback
+ * @return a handle to the hook so it can be removed later
+ * @see evrpc_remove_hook()
+ */
+EVENT2_EXPORT_SYMBOL
+void *evrpc_add_hook(void *vbase,
+ enum EVRPC_HOOK_TYPE hook_type,
+ int (*cb)(void *, struct evhttp_request *, struct evbuffer *, void *),
+ void *cb_arg);
+
+/** removes a previously added hook
+ *
+ * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool
+ * @param hook_type either INPUT or OUTPUT
+ * @param handle a handle returned by evrpc_add_hook()
+ * @return 1 on success or 0 on failure
+ * @see evrpc_add_hook()
+ */
+EVENT2_EXPORT_SYMBOL
+int evrpc_remove_hook(void *vbase,
+ enum EVRPC_HOOK_TYPE hook_type,
+ void *handle);
+
+/** resume a paused request
+ *
+ * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool
+ * @param ctx the context pointer provided to the original hook call
+ */
+EVENT2_EXPORT_SYMBOL
+int evrpc_resume_request(void *vbase, void *ctx, enum EVRPC_HOOK_RESULT res);
+
+/** adds meta data to request
+ *
+ * evrpc_hook_add_meta() allows hooks to add meta data to a request. for
+ * a client request, the meta data can be inserted by an outgoing request hook
+ * and retrieved by the incoming request hook.
+ *
+ * @param ctx the context provided to the hook call
+ * @param key a NUL-terminated c-string
+ * @param data the data to be associated with the key
+ * @param data_size the size of the data
+ */
+EVENT2_EXPORT_SYMBOL
+void evrpc_hook_add_meta(void *ctx, const char *key,
+ const void *data, size_t data_size);
+
+/** retrieves meta data previously associated
+ *
+ * evrpc_hook_find_meta() can be used to retrieve meta data associated to a
+ * request by a previous hook.
+ * @param ctx the context provided to the hook call
+ * @param key a NUL-terminated c-string
+ * @param data pointer to a data pointer that will contain the retrieved data
+ * @param data_size pointer to the size of the data
+ * @return 0 on success or -1 on failure
+ */
+EVENT2_EXPORT_SYMBOL
+int evrpc_hook_find_meta(void *ctx, const char *key,
+ void **data, size_t *data_size);
+
+/**
+ * returns the connection object associated with the request
+ *
+ * @param ctx the context provided to the hook call
+ * @return a pointer to the evhttp_connection object or NULL if an error
+ * occurred
+ */
+EVENT2_EXPORT_SYMBOL
+struct evhttp_connection *evrpc_hook_get_connection(void *ctx);
+
+/**
+ Function for sending a generic RPC request.
+
+ Do not call this function directly, use EVRPC_MAKE_REQUEST() instead.
+
+ @see EVRPC_MAKE_REQUEST()
+ */
+EVENT2_EXPORT_SYMBOL
+int evrpc_send_request_generic(struct evrpc_pool *pool,
+ void *request, void *reply,
+ void (*cb)(struct evrpc_status *, void *, void *, void *),
+ void *cb_arg,
+ const char *rpcname,
+ void (*req_marshal)(struct evbuffer *, void *),
+ void (*rpl_clear)(void *),
+ int (*rpl_unmarshal)(void *, struct evbuffer *));
+
+/**
+ Function for registering a generic RPC with the RPC base.
+
+ Do not call this function directly, use EVRPC_REGISTER() instead.
+
+ @see EVRPC_REGISTER()
+ */
+EVENT2_EXPORT_SYMBOL
+int evrpc_register_generic(struct evrpc_base *base, const char *name,
+ void (*callback)(struct evrpc_req_generic *, void *), void *cbarg,
+ void *(*req_new)(void *), void *req_new_arg, void (*req_free)(void *),
+ int (*req_unmarshal)(void *, struct evbuffer *),
+ void *(*rpl_new)(void *), void *rpl_new_arg, void (*rpl_free)(void *),
+ int (*rpl_complete)(void *),
+ void (*rpl_marshal)(struct evbuffer *, void *));
+
+/** accessors for obscure and undocumented functionality */
+EVENT2_EXPORT_SYMBOL
+struct evrpc_pool* evrpc_request_get_pool(struct evrpc_request_wrapper *ctx);
+EVENT2_EXPORT_SYMBOL
+void evrpc_request_set_pool(struct evrpc_request_wrapper *ctx,
+ struct evrpc_pool *pool);
+EVENT2_EXPORT_SYMBOL
+void evrpc_request_set_cb(struct evrpc_request_wrapper *ctx,
+ void (*cb)(struct evrpc_status*, void *request, void *reply, void *arg),
+ void *cb_arg);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* EVENT2_RPC_H_INCLUDED_ */