Initial import.

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diff --git a/chromium/third_party/libevent/evrpc.h b/chromium/third_party/libevent/evrpc.h
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+/*
+ * Copyright (c) 2006 Niels Provos <provos@citi.umich.edu>
+ * All rights reserved.
+ *
+ * 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 _EVRPC_H_
+#define _EVRPC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** @file evrpc.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 invokved.   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.
+ */
+
+struct evbuffer;
+struct event_base;
+struct evrpc_req_generic;
+
+/* Encapsulates a request */
+struct evrpc {
+	TAILQ_ENTRY(evrpc) next;
+
+	/* the URI at which the request handler lives */
+	const char* uri;
+
+	/* creates a new request structure */
+	void *(*request_new)(void);
+
+	/* frees the request structure */
+	void (*request_free)(void *);
+
+	/* unmarshals the buffer into the proper request structure */
+	int (*request_unmarshal)(void *, struct evbuffer *);
+
+	/* creates a new reply structure */
+	void *(*reply_new)(void);
+
+	/* creates a new reply structure */
+	void (*reply_free)(void *);
+
+	/* verifies that the reply is valid */
+	int (*reply_complete)(void *);
+	
+	/* marshals the reply into a buffer */
+	void (*reply_marshal)(struct evbuffer*, void *);
+
+	/* the callback invoked for each received rpc */
+	void (*cb)(struct evrpc_req_generic *, void *);
+	void *cb_arg;
+
+	/* reference for further configuration */
+	struct evrpc_base *base;
+};
+
+/** 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;
+
+/* We alias the RPC specific structs to this voided one */
+struct evrpc_req_generic {
+	/* the unmarshaled request object */
+	void *request;
+
+	/* the empty reply object that needs to be filled in */
+	void *reply;
+
+	/* 
+	 * the static structure for this rpc; that can be used to
+	 * automatically unmarshal and marshal the http buffers.
+	 */
+	struct evrpc *rpc;
+
+	/*
+	 * the http request structure on which we need to answer.
+	 */
+	struct evhttp_request* http_req;
+
+	/*
+	 * callback to reply and finish answering this rpc
+	 */
+	void (*done)(struct evrpc_req_generic* rpc); 
+};
+
+/** 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 reqstruct* request; \
+	struct rplystruct* reply; \
+	struct evrpc* rpc; \
+	struct evhttp_request* http_req; \
+	void (*done)(struct evrpc_status *, \
+	    struct evrpc* rpc, void *request, void *reply);	     \
+};								     \
+int evrpc_send_request_##rpcname(struct evrpc_pool *, \
+    struct reqstruct *, struct rplystruct *, \
+    void (*)(struct evrpc_status *, \
+	struct reqstruct *, struct rplystruct *, void *cbarg),	\
+    void *);
+
+/** 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) { \
+	struct evrpc_status status;				    \
+	struct evrpc_request_wrapper *ctx;			    \
+	ctx = (struct evrpc_request_wrapper *) \
+	    malloc(sizeof(struct evrpc_request_wrapper));	    \
+	if (ctx == NULL)					    \
+		goto error;					    \
+	ctx->pool = pool;					    \
+	ctx->evcon = NULL;					    \
+	ctx->name = strdup(#rpcname);				    \
+	if (ctx->name == NULL) {				    \
+		free(ctx);					    \
+		goto error;					    \
+	}							    \
+	ctx->cb = (void (*)(struct evrpc_status *, \
+		void *, void *, void *))cb;			    \
+	ctx->cb_arg = cbarg;					    \
+	ctx->request = (void *)request;				    \
+	ctx->reply = (void *)reply;				    \
+	ctx->request_marshal = (void (*)(struct evbuffer *, void *))reqstruct##_marshal; \
+	ctx->reply_clear = (void (*)(void *))rplystruct##_clear;    \
+	ctx->reply_unmarshal = (int (*)(void *, struct evbuffer *))rplystruct##_unmarshal; \
+	return (evrpc_make_request(ctx));			    \
+error:								    \
+	memset(&status, 0, sizeof(status));			    \
+	status.error = EVRPC_STATUS_ERR_UNSTARTED;		    \
+	(*(cb))(&status, request, reply, cbarg);		    \
+	return (-1);						    \
+}
+
+/** 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
+
+/** 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); \
+  _req->done(_req); \
+} while (0)
+  
+
+/* Takes a request object and fills it in with the right magic */
+#define EVRPC_REGISTER_OBJECT(rpc, name, request, reply) \
+  do { \
+    (rpc)->uri = strdup(#name); \
+    if ((rpc)->uri == NULL) {			 \
+      fprintf(stderr, "failed to register object\n");	\
+      exit(1);						\
+    } \
+    (rpc)->request_new = (void *(*)(void))request##_new; \
+    (rpc)->request_free = (void (*)(void *))request##_free; \
+    (rpc)->request_unmarshal = (int (*)(void *, struct evbuffer *))request##_unmarshal; \
+    (rpc)->reply_new = (void *(*)(void))reply##_new; \
+    (rpc)->reply_free = (void (*)(void *))reply##_free; \
+    (rpc)->reply_complete = (int (*)(void *))reply##_complete; \
+    (rpc)->reply_marshal = (void (*)(struct evbuffer*, void *))reply##_marshal; \
+  } 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
+ * @see evrpc_free()
+ */
+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
+ */
+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) \
+  do { \
+    struct evrpc* rpc = (struct evrpc *)calloc(1, sizeof(struct evrpc)); \
+    EVRPC_REGISTER_OBJECT(rpc, name, request, reply); \
+    evrpc_register_rpc(base, rpc, \
+	(void (*)(struct evrpc_req_generic*, void *))callback, cbarg);	\
+  } while (0)
+
+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)
+
+int evrpc_unregister_rpc(struct evrpc_base *base, const char *name);
+
+/*
+ * Client-side RPC support
+ */
+
+struct evrpc_pool;
+struct evhttp_connection;
+
+/** 
+ * provides information about the completed RPC request.
+ */
+struct evrpc_status {
+#define EVRPC_STATUS_ERR_NONE		0
+#define EVRPC_STATUS_ERR_TIMEOUT	1
+#define EVRPC_STATUS_ERR_BADPAYLOAD	2
+#define EVRPC_STATUS_ERR_UNSTARTED	3
+#define EVRPC_STATUS_ERR_HOOKABORTED	4
+	int error;
+
+	/* for looking at headers or other information */
+	struct evhttp_request *http_req;
+};
+
+struct evrpc_request_wrapper {
+	TAILQ_ENTRY(evrpc_request_wrapper) next;
+
+        /* pool on which this rpc request is being made */
+        struct evrpc_pool *pool;
+
+        /* connection on which the request is being sent */
+	struct evhttp_connection *evcon;
+
+	/* event for implementing request timeouts */
+	struct event ev_timeout;
+
+	/* the name of the rpc */
+	char *name;
+
+	/* callback */
+	void (*cb)(struct evrpc_status*, void *request, void *reply, void *arg);
+	void *cb_arg;
+
+	void *request;
+	void *reply;
+
+	/* unmarshals the buffer into the proper request structure */
+	void (*request_marshal)(struct evbuffer *, void *);
+
+	/* removes all stored state in the reply */
+	void (*reply_clear)(void *);
+
+	/* marshals the reply into a buffer */
+	int (*reply_unmarshal)(void *, struct evbuffer*);
+};
+
+/** 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)
+
+int evrpc_make_request(struct evrpc_request_wrapper *);
+
+/** 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
+ * @see evrpc_pool_free()
+ */
+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()
+ */
+void evrpc_pool_free(struct evrpc_pool *pool);
+/*
+ * adds a connection over which rpc can be dispatched.  the connection
+ * object must have been newly created.
+ */
+void evrpc_pool_add_connection(struct evrpc_pool *, 
+    struct evhttp_connection *);
+
+/**
+ * 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.
+ */
+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
+
+/** adds a processing hook to either an rpc base or rpc pool
+ *
+ * If a hook returns -1, the processing is aborted.
+ *
+ * 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()
+ */
+void *evrpc_add_hook(void *vbase,
+    enum EVRPC_HOOK_TYPE hook_type,
+    int (*cb)(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()
+ */
+int evrpc_remove_hook(void *vbase,
+    enum EVRPC_HOOK_TYPE hook_type,
+    void *handle);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _EVRPC_H_ */