Files correlati : Commento : Aggiornata cUrl alla ultima versione su Github: 7.56.1 git-svn-id: svn://10.65.10.50/branches/R_10_00@24203 c028cbd2-c16b-5b4b-a496-9718f37d4682
		
			
				
	
	
		
			134 lines
		
	
	
		
			5.1 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
			
		
		
	
	
			134 lines
		
	
	
		
			5.1 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
| .\" **************************************************************************
 | |
| .\" *                                  _   _ ____  _
 | |
| .\" *  Project                     ___| | | |  _ \| |
 | |
| .\" *                             / __| | | | |_) | |
 | |
| .\" *                            | (__| |_| |  _ <| |___
 | |
| .\" *                             \___|\___/|_| \_\_____|
 | |
| .\" *
 | |
| .\" * Copyright (C) 1998 - 2015, 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 https://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.
 | |
| .\" *
 | |
| .\" **************************************************************************
 | |
| .\"
 | |
| .TH CURLMOPT_PUSHFUNCTION 3 "1 Jun 2015" "libcurl 7.44.0" "curl_multi_setopt options"
 | |
| .SH NAME
 | |
| CURLMOPT_PUSHFUNCTION \- callback that approves or denies server pushes
 | |
| .SH SYNOPSIS
 | |
| .nf
 | |
| #include <curl/curl.h>
 | |
| 
 | |
| char *curl_pushheader_bynum(struct curl_pushheaders *h, size_t num);
 | |
| char *curl_pushheader_byname(struct curl_pushheaders *h, const char *name);
 | |
| 
 | |
| int curl_push_callback(CURL *parent,
 | |
|                        CURL *easy,
 | |
|                        size_t num_headers,
 | |
|                        struct curl_pushheaders *headers,
 | |
|                        void *userp);
 | |
| 
 | |
| CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHFUNCTION,
 | |
|                             curl_push_callback func);
 | |
| .fi
 | |
| .SH DESCRIPTION
 | |
| This callback gets called when a new HTTP/2 stream is being pushed by the
 | |
| server (using the PUSH_PROMISE frame). If no push callback is set, all offered
 | |
| pushes will be denied automatically.
 | |
| .SH CALLBACK DESCRIPTION
 | |
| The callback gets its arguments like this:
 | |
| 
 | |
| \fIparent\fP is the handle of the stream on which this push arrives. The new
 | |
| handle has been duphandle()d from the parent, meaning that it has gotten all
 | |
| its options inherited. It is then up to the application to alter any options
 | |
| if desired.
 | |
| 
 | |
| \fIeasy\fP is a newly created handle that represents this upcoming transfer.
 | |
| 
 | |
| \fInum_headers\fP is the number of name+value pairs that was received and can
 | |
| be accessed
 | |
| 
 | |
| \fIheaders\fP is a handle used to access push headers using the accessor
 | |
| functions described below. This only accesses and provides the PUSH_PROMISE
 | |
| headers, the normal response headers will be provided in the header callback
 | |
| as usual.
 | |
| 
 | |
| \fIuserp\fP is the pointer set with \fICURLMOPT_PUSHDATA(3)\fP
 | |
| 
 | |
| If the callback returns CURL_PUSH_OK, the 'easy' handle will be added to the
 | |
| multi handle, the callback must not do that by itself.
 | |
| 
 | |
| The callback can access PUSH_PROMISE headers with two accessor
 | |
| functions. These functions can only be used from within this callback and they
 | |
| can only access the PUSH_PROMISE headers. The normal response headers will be
 | |
| passed to the header callback for pushed streams just as for normal streams.
 | |
| .IP curl_pushheader_bynum
 | |
| Returns the header at index 'num' (or NULL). The returned pointer points to a
 | |
| "name:value" string that will be freed when this callback returns.
 | |
| .IP curl_pushheader_byname
 | |
| Returns the value for the given header name (or NULL). This is a shortcut so
 | |
| that the application doesn't have to loop through all headers to find the one
 | |
| it is interested in. The data pointed will be freed when this callback
 | |
| returns. If more than one header field use the same name, this returns only
 | |
| the first one.
 | |
| .SH CALLBACK RETURN VALUE
 | |
| .IP "CURL_PUSH_OK (0)"
 | |
| The application has accepted the stream and it can now start receiving data,
 | |
| the ownership of the CURL handle has been taken over by the application.
 | |
| .IP "CURL_PUSH_DENY (1)"
 | |
| The callback denies the stream and no data for this will reach the
 | |
| application, the easy handle will be destroyed by libcurl.
 | |
| .IP *
 | |
| All other return codes are reserved for future use.
 | |
| .SH DEFAULT
 | |
| NULL, no callback
 | |
| .SH PROTOCOLS
 | |
| HTTP(S) (HTTP/2 only)
 | |
| .SH EXAMPLE
 | |
| .nf
 | |
| /* only allow pushes for file names starting with "push-" */
 | |
| int push_callback(CURL *parent,
 | |
|                   CURL *easy,
 | |
|                   size_t num_headers,
 | |
|                   struct curl_pushheaders *headers,
 | |
|                   void *userp)
 | |
| {
 | |
|   char *headp;
 | |
|   int *transfers = (int *)userp;
 | |
|   FILE *out;
 | |
|   headp = curl_pushheader_byname(headers, ":path");
 | |
|   if(headp && !strncmp(headp, "/push-", 6)) {
 | |
|     fprintf(stderr, "The PATH is %s\\n", headp);
 | |
| 
 | |
|     /* save the push here */
 | |
|     out = fopen("pushed-stream", "wb");
 | |
| 
 | |
|     /* write to this file */
 | |
|     curl_easy_setopt(easy, CURLOPT_WRITEDATA, out);
 | |
| 
 | |
|     (*transfers)++; /* one more */
 | |
| 
 | |
|     return CURL_PUSH_OK;
 | |
|   }
 | |
|   return CURL_PUSH_DENY;
 | |
| }
 | |
| 
 | |
| curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, push_callback);
 | |
| curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &counter);
 | |
| .fi
 | |
| .SH AVAILABILITY
 | |
| Added in 7.44.0
 | |
| .SH RETURN VALUE
 | |
| Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
 | |
| .SH "SEE ALSO"
 | |
| .BR CURLMOPT_PUSHDATA "(3), " CURLMOPT_PIPELINING "(3), " CURLOPT_PIPEWAIT "(3), "
 | |
| .BR RFC 7540
 |