Files correlati : omento : Aggiornata cUrl alla ultima versione su Github: 7.56.1 git-svn-id: svn://10.65.10.50/branches/R_10_00@24202 c028cbd2-c16b-5b4b-a496-9718f37d4682
		
			
				
	
	
		
			129 lines
		
	
	
		
			4.9 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
			
		
		
	
	
			129 lines
		
	
	
		
			4.9 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
.\" **************************************************************************
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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 - 2017, 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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.TH CURLOPT_OPENSOCKETFUNCTION 3 "16 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
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.SH NAME
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CURLOPT_OPENSOCKETFUNCTION \- set callback for opening sockets
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.SH SYNOPSIS
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.nf
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#include <curl/curl.h>
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typedef enum  {
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  CURLSOCKTYPE_IPCXN,  /* socket created for a specific IP connection */
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  CURLSOCKTYPE_ACCEPT, /* socket created by accept() call */
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  CURLSOCKTYPE_LAST    /* never use */
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} curlsocktype;
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struct curl_sockaddr {
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  int family;
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  int socktype;
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  int protocol;
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  unsigned int addrlen;
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  struct sockaddr addr;
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};
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curl_socket_t opensocket_callback(void *clientp,
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                                  curlsocktype purpose,
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                                  struct curl_sockaddr *address);
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CURLcode curl_easy_setopt(CURL *handle, CURLOPT_OPENSOCKETFUNCTION, opensocket_callback);
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.SH DESCRIPTION
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Pass a pointer to your callback function, which should match the prototype
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shown above.
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This callback function gets called by libcurl instead of the \fIsocket(2)\fP
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call. The callback's \fIpurpose\fP argument identifies the exact purpose for
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this particular socket: \fICURLSOCKTYPE_IPCXN\fP is for IP based connections
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and \fICURLSOCKTYPE_ACCEPT\fP is for sockets created after accept() - such as
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when doing active FTP. Future versions of libcurl may support more
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purposes.
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The \fIclientp\fP pointer contains whatever user-defined value set using the
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\fICURLOPT_OPENSOCKETDATA(3)\fP function.
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The callback gets the resolved peer address as the \fIaddress\fP argument and
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is allowed to modify the address or refuse to connect completely. The callback
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function should return the newly created socket or \fICURL_SOCKET_BAD\fP in
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case no connection could be established or another error was detected. Any
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additional \fIsetsockopt(2)\fP calls can of course be done on the socket at
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the user's discretion.  A \fICURL_SOCKET_BAD\fP return value from the callback
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function will signal an unrecoverable error to libcurl and it will return
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\fICURLE_COULDNT_CONNECT\fP from the function that triggered this callback.
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This return code can be used for IP address blacklisting.
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If you want to pass in a socket with an already established connection, pass
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the socket back with this callback and then use
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\fICURLOPT_SOCKOPTFUNCTION(3)\fP to signal that it already is connected.
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.SH DEFAULT
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The default behavior is the equivalent of this:
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.nf
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   return socket(addr->family, addr->socktype, addr->protocol);
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.fi
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.SH PROTOCOLS
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All
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.SH EXAMPLE
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.nf
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/* make libcurl use the already established socket 'sockfd' */
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static curl_socket_t opensocket(void *clientp,
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                                curlsocktype purpose,
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                                struct curl_sockaddr *address)
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{
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  curl_socket_t sockfd;
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  sockfd = *(curl_socket_t *)clientp;
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  /* the actual externally set socket is passed in via the OPENSOCKETDATA
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     option */
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  return sockfd;
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}
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static int sockopt_callback(void *clientp, curl_socket_t curlfd,
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                            curlsocktype purpose)
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{
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  /* This return code was added in libcurl 7.21.5 */
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  return CURL_SOCKOPT_ALREADY_CONNECTED;
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}
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curl = curl_easy_init();
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if(curl) {
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  /* libcurl will internally think that you connect to the host
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   * and port that you specify in the URL option. */
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  curl_easy_setopt(curl, CURLOPT_URL, "http://99.99.99.99:9999");
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  /* call this function to get a socket */
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  curl_easy_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, opensocket);
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  curl_easy_setopt(curl, CURLOPT_OPENSOCKETDATA, &sockfd);
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  /* call this function to set options for the socket */
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  curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
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  res = curl_easy_perform(curl);
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  curl_easy_cleanup(curl);
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}
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.fi
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.SH AVAILABILITY
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Added in 7.17.1.
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.SH RETURN VALUE
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Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
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.SH "SEE ALSO"
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.BR CURLOPT_OPENSOCKETDATA "(3), " CURLOPT_SOCKOPTFUNCTION "(3), "
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.BR CURLOPT_CLOSESOCKETFUNCTION "(3), "
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