185 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			185 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef HEADER_CURL_ASYN_H
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| #define HEADER_CURL_ASYN_H
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| /***************************************************************************
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|  *                                  _   _ ____  _
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|  *  Project                     ___| | | |  _ \| |
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|  *                             / __| | | | |_) | |
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|  *                            | (__| |_| |  _ <| |___
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|  *                             \___|\___/|_| \_\_____|
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|  *
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|  * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
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|  *
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|  * This software is licensed as described in the file COPYING, which
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|  * you should have received as part of this distribution. The terms
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|  * are also available at https://curl.haxx.se/docs/copyright.html.
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|  *
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|  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
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|  * copies of the Software, and permit persons to whom the Software is
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|  * furnished to do so, under the terms of the COPYING file.
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|  *
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|  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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|  * KIND, either express or implied.
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|  *
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|  ***************************************************************************/
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| 
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| #include "curl_setup.h"
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| #include "curl_addrinfo.h"
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| 
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| struct addrinfo;
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| struct hostent;
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| struct Curl_easy;
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| struct connectdata;
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| struct Curl_dns_entry;
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| 
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| /*
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|  * This header defines all functions in the internal asynch resolver interface.
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|  * All asynch resolvers need to provide these functions.
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|  * asyn-ares.c and asyn-thread.c are the current implementations of asynch
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|  * resolver backends.
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|  */
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| 
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| /*
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|  * Curl_resolver_global_init()
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|  *
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|  * Called from curl_global_init() to initialize global resolver environment.
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|  * Returning anything else than CURLE_OK fails curl_global_init().
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|  */
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| int Curl_resolver_global_init(void);
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| 
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| /*
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|  * Curl_resolver_global_cleanup()
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|  * Called from curl_global_cleanup() to destroy global resolver environment.
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|  */
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| void Curl_resolver_global_cleanup(void);
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| 
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| /*
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|  * Curl_resolver_init()
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|  * Called from curl_easy_init() -> Curl_open() to initialize resolver
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|  * URL-state specific environment ('resolver' member of the UrlState
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|  * structure).  Should fill the passed pointer by the initialized handler.
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|  * Returning anything else than CURLE_OK fails curl_easy_init() with the
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|  * correspondent code.
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|  */
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| CURLcode Curl_resolver_init(struct Curl_easy *easy, void **resolver);
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| 
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| /*
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|  * Curl_resolver_cleanup()
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|  * Called from curl_easy_cleanup() -> Curl_close() to cleanup resolver
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|  * URL-state specific environment ('resolver' member of the UrlState
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|  * structure).  Should destroy the handler and free all resources connected to
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|  * it.
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|  */
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| void Curl_resolver_cleanup(void *resolver);
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| 
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| /*
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|  * Curl_resolver_duphandle()
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|  * Called from curl_easy_duphandle() to duplicate resolver URL-state specific
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|  * environment ('resolver' member of the UrlState structure).  Should
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|  * duplicate the 'from' handle and pass the resulting handle to the 'to'
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|  * pointer.  Returning anything else than CURLE_OK causes failed
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|  * curl_easy_duphandle() call.
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|  */
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| CURLcode Curl_resolver_duphandle(struct Curl_easy *easy, void **to,
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|                                  void *from);
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| 
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| /*
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|  * Curl_resolver_cancel().
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|  *
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|  * It is called from inside other functions to cancel currently performing
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|  * resolver request. Should also free any temporary resources allocated to
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|  * perform a request.  This never waits for resolver threads to complete.
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|  *
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|  * It is safe to call this when conn is in any state.
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|  */
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| void Curl_resolver_cancel(struct connectdata *conn);
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| 
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| /*
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|  * Curl_resolver_kill().
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|  *
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|  * This acts like Curl_resolver_cancel() except it will block until any threads
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|  * associated with the resolver are complete.  This never blocks for resolvers
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|  * that do not use threads.  This is intended to be the "last chance" function
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|  * that cleans up an in-progress resolver completely (before its owner is about
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|  * to die).
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|  *
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|  * It is safe to call this when conn is in any state.
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|  */
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| void Curl_resolver_kill(struct connectdata *conn);
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| 
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| /* Curl_resolver_getsock()
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|  *
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|  * This function is called from the multi_getsock() function.  'sock' is a
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|  * pointer to an array to hold the file descriptors, with 'numsock' being the
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|  * size of that array (in number of entries). This function is supposed to
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|  * return bitmask indicating what file descriptors (referring to array indexes
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|  * in the 'sock' array) to wait for, read/write.
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|  */
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| int Curl_resolver_getsock(struct connectdata *conn, curl_socket_t *sock,
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|                           int numsocks);
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| 
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| /*
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|  * Curl_resolver_is_resolved()
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|  *
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|  * Called repeatedly to check if a previous name resolve request has
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|  * completed. It should also make sure to time-out if the operation seems to
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|  * take too long.
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|  *
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|  * Returns normal CURLcode errors.
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|  */
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| CURLcode Curl_resolver_is_resolved(struct connectdata *conn,
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|                                    struct Curl_dns_entry **dns);
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| 
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| /*
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|  * Curl_resolver_wait_resolv()
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|  *
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|  * Waits for a resolve to finish. This function should be avoided since using
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|  * this risk getting the multi interface to "hang".
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|  *
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|  * If 'entry' is non-NULL, make it point to the resolved dns entry
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|  *
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|  * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved,
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|  * CURLE_OPERATION_TIMEDOUT if a time-out occurred, or other errors.
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|  */
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| CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
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|                                    struct Curl_dns_entry **dnsentry);
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| 
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| /*
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|  * Curl_resolver_getaddrinfo() - when using this resolver
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|  *
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|  * Returns name information about the given hostname and port number. If
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|  * successful, the 'hostent' is returned and the forth argument will point to
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|  * memory we need to free after use. That memory *MUST* be freed with
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|  * Curl_freeaddrinfo(), nothing else.
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|  *
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|  * Each resolver backend must of course make sure to return data in the
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|  * correct format to comply with this.
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|  */
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| Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn,
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|                                          const char *hostname,
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|                                          int port,
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|                                          int *waitp);
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| 
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| #ifndef CURLRES_ASYNCH
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| /* convert these functions if an asynch resolver isn't used */
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| #define Curl_resolver_cancel(x) Curl_nop_stmt
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| #define Curl_resolver_kill(x) Curl_nop_stmt
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| #define Curl_resolver_is_resolved(x,y) CURLE_COULDNT_RESOLVE_HOST
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| #define Curl_resolver_wait_resolv(x,y) CURLE_COULDNT_RESOLVE_HOST
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| #define Curl_resolver_getsock(x,y,z) 0
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| #define Curl_resolver_duphandle(x,y,z) CURLE_OK
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| #define Curl_resolver_init(x,y) CURLE_OK
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| #define Curl_resolver_global_init() CURLE_OK
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| #define Curl_resolver_global_cleanup() Curl_nop_stmt
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| #define Curl_resolver_cleanup(x) Curl_nop_stmt
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| #endif
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| 
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| #ifdef CURLRES_ASYNCH
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| #define Curl_resolver_asynch() 1
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| #else
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| #define Curl_resolver_asynch() 0
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| #endif
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| 
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| 
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| /********** end of generic resolver interface functions *****************/
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| #endif /* HEADER_CURL_ASYN_H */
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