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| .\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. |
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| .TH CURLOPT_HSTSWRITEFUNCTION 3 "14 Sep 2020" libcurl libcurl |
| .SH NAME |
| CURLOPT_HSTSWRITEFUNCTION \- write callback for HSTS hosts |
| .SH SYNOPSIS |
| .nf |
| #include <curl/curl.h> |
| |
| struct curl_hstsentry { |
| char *name; |
| size_t namelen; |
| unsigned int includeSubDomains:1; |
| char expire[18]; /* YYYYMMDD HH:MM:SS [null-terminated] */ |
| }; |
| |
| struct curl_index { |
| size_t index; /* the provided entry's "index" or count */ |
| size_t total; /* total number of entries to save */ |
| }; |
| |
| CURLSTScode hstswrite(CURL *easy, struct curl_hstsentry *sts, |
| struct curl_index *count, void *clientp); |
| |
| CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTSWRITEFUNCTION, hstswrite); |
| .fi |
| .SH DESCRIPTION |
| Pass a pointer to your callback function, as the prototype shows above. |
| |
| This callback function gets called by libcurl repeatedly to allow the |
| application to store the in-memory HSTS cache when libcurl is about to discard |
| it. |
| |
| Set the \fIclientp\fP argument with the \fICURLOPT_HSTSWRITEDATA(3)\fP option |
| or it is NULL. |
| When the callback is invoked, the \fIsts\fP pointer points to a populated |
| struct: Read the host name to 'name' (it is \fInamelen\fP bytes long and null |
| terminated. The \fIincludeSubDomains\fP field is non-zero if the entry matches |
| subdomains. The \fIexpire\fP string is a date stamp null-terminated string |
| using the syntax YYYYMMDD HH:MM:SS. |
| |
| The callback should return \fICURLSTS_OK\fP if it succeeded and is prepared to |
| be called again (for another host) or \fICURLSTS_DONE\fP if there is nothing |
| more to do. It can also return \fICURLSTS_FAIL\fP to signal error. |
| |
| This option does not enable HSTS, you need to use \fICURLOPT_HSTS_CTRL(3)\fP to |
| do that. |
| .SH DEFAULT |
| NULL - no callback. |
| .SH PROTOCOLS |
| This feature is only used for HTTP(S) transfer. |
| .SH EXAMPLE |
| .nf |
| struct priv { |
| void *custom; |
| }; |
| |
| static CURLSTScode hswr_cb(CURL *easy, struct curl_hstsentry *sts, |
| struct curl_index *count, void *clientp) |
| { |
| /* save the passed in HSTS data somewhere */ |
| return CURLSTS_OK; |
| } |
| |
| int main(void) |
| { |
| CURL *curl = curl_easy_init(); |
| if(curl) { |
| struct priv my_stuff; |
| CURLcode res; |
| |
| /* set HSTS read callback */ |
| curl_easy_setopt(curl, CURLOPT_HSTSWRITEFUNCTION, hswr_cb); |
| |
| /* pass in suitable argument to the callback */ |
| curl_easy_setopt(curl, CURLOPT_HSTSWRITEDATA, &my_stuff); |
| |
| res = curl_easy_perform(curl); |
| } |
| } |
| .fi |
| .SH AVAILABILITY |
| Added in 7.74.0 |
| .SH RETURN VALUE |
| This returns CURLE_OK. |
| .SH "SEE ALSO" |
| .BR CURLOPT_HSTS (3), |
| .BR CURLOPT_HSTS_CTRL (3), |
| .BR CURLOPT_HSTSWRITEDATA (3), |
| .BR CURLOPT_HSTSWRITEFUNCTION (3) |