#ifndef HEADER_CURL_ASYN_H #define HEADER_CURL_ASYN_H /*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at http://curl.haxx.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ***************************************************************************/ #include "setup.h" #include "curl_addrinfo.h" struct addrinfo; struct hostent; struct SessionHandle; struct connectdata; struct Curl_dns_entry; /* * This header defines all functions in the internal asynch resolver interface. * All asynch resolvers need to provide these functions. * asyn-ares.c and asyn-thread.c are the current implementations of asynch * resolver backends. */ /* * Curl_resolver_global_init() * * Called from curl_global_init() to initialize global resolver environment. * Returning anything else than CURLE_OK fails curl_global_init(). */ int Curl_resolver_global_init(void); /* * Curl_resolver_global_cleanup() * Called from curl_global_cleanup() to destroy global resolver environment. */ void Curl_resolver_global_cleanup(void); /* * Curl_resolver_init() * Called from curl_easy_init() -> Curl_open() to initialize resolver * URL-state specific environment ('resolver' member of the UrlState * structure). Should fill the passed pointer by the initialized handler. * Returning anything else than CURLE_OK fails curl_easy_init() with the * correspondent code. */ CURLcode Curl_resolver_init(void **resolver); /* * Curl_resolver_cleanup() * Called from curl_easy_cleanup() -> Curl_close() to cleanup resolver * URL-state specific environment ('resolver' member of the UrlState * structure). Should destroy the handler and free all resources connected to * it. */ void Curl_resolver_cleanup(void *resolver); /* * Curl_resolver_duphandle() * Called from curl_easy_duphandle() to duplicate resolver URL-state specific * environment ('resolver' member of the UrlState structure). Should * duplicate the 'from' handle and pass the resulting handle to the 'to' * pointer. Returning anything else than CURLE_OK causes failed * curl_easy_duphandle() call. */ int Curl_resolver_duphandle(void **to, void *from); /* * Curl_resolver_cancel(). * * It is called from inside other functions to cancel currently performing * resolver request. Should also free any temporary resources allocated to * perform a request. */ void Curl_resolver_cancel(struct connectdata *conn); /* Curl_resolver_getsock() * * This function is called from the multi_getsock() function. 'sock' is a * pointer to an array to hold the file descriptors, with 'numsock' being the * size of that array (in number of entries). This function is supposed to * return bitmask indicating what file descriptors (referring to array indexes * in the 'sock' array) to wait for, read/write. */ int Curl_resolver_getsock(struct connectdata *conn, curl_socket_t *sock, int numsocks); /* * Curl_resolver_is_resolved() * * Called repeatedly to check if a previous name resolve request has * completed. It should also make sure to time-out if the operation seems to * take too long. * * Returns normal CURLcode errors. */ CURLcode Curl_resolver_is_resolved(struct connectdata *conn, struct Curl_dns_entry **dns); /* * Curl_resolver_wait_resolv() * * waits for a resolve to finish. This function should be avoided since using * this risk getting the multi interface to "hang". * * If 'entry' is non-NULL, make it point to the resolved dns entry * * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and * CURLE_OPERATION_TIMEDOUT if a time-out occurred. */ CURLcode Curl_resolver_wait_resolv(struct connectdata *conn, struct Curl_dns_entry **dnsentry); /* * Curl_resolver_getaddrinfo() - when using this resolver * * Returns name information about the given hostname and port number. If * successful, the 'hostent' is returned and the forth argument will point to * memory we need to free after use. That memory *MUST* be freed with * Curl_freeaddrinfo(), nothing else. * * Each resolver backend must of course make sure to return data in the * correct format to comply with this. */ Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp); #ifndef CURLRES_ASYNCH /* convert these functions if an asynch resolver isn't used */ #define Curl_resolver_cancel(x) Curl_nop_stmt #define Curl_resolver_is_resolved(x,y) CURLE_COULDNT_RESOLVE_HOST #define Curl_resolver_wait_resolv(x,y) CURLE_COULDNT_RESOLVE_HOST #define Curl_resolver_getsock(x,y,z) 0 #define Curl_resolver_duphandle(x,y) CURLE_OK #define Curl_resolver_init(x) CURLE_OK #define Curl_resolver_global_init() CURLE_OK #define Curl_resolver_global_cleanup() Curl_nop_stmt #define Curl_resolver_cleanup(x) Curl_nop_stmt #endif #ifdef CURLRES_ASYNCH #define Curl_resolver_asynch() 1 #else #define Curl_resolver_asynch() 0 #endif /********** end of generic resolver interface functions *****************/ #endif /* HEADER_CURL_ASYN_H */