Add Max Age CURL Option (#360)

* add max age option to CURL system crate

* correctly identify constant and expose Rust API

* correct API

curl-sys/lib.rs

@@ -582,6 +582,8 @@ pub const CURLOPT_PROXY_CAPATH: CURLoption = CURLOPTTYPE_OBJECTPOINT + 247;
 pub const CURLOPT_PROXY_SSLCERT: CURLoption = CURLOPTTYPE_OBJECTPOINT + 254;
 pub const CURLOPT_PROXY_SSLKEY: CURLoption = CURLOPTTYPE_OBJECTPOINT + 256;
 
+pub const CURLOPT_MAXAGE_CONN: CURLoption = CURLOPTTYPE_LONG + 288;
+
 pub const CURL_IPRESOLVE_WHATEVER: c_int = 0;
 pub const CURL_IPRESOLVE_V4: c_int = 1;
 pub const CURL_IPRESOLVE_V6: c_int = 2;

src/easy/handle.rs

@@ -905,6 +905,11 @@ impl Easy {
         self.inner.max_connects(max)
     }
 
+    /// Same as [`Easy2::maxage_conn`](struct.Easy2.html#method.maxage_conn)
+    pub fn maxage_conn(&mut self, max_age: Duration) -> Result<(), Error> {
+        self.inner.maxage_conn(max_age)
+    }
+
     /// Same as [`Easy2::fresh_connect`](struct.Easy2.html#method.fresh_connect)
     pub fn fresh_connect(&mut self, enable: bool) -> Result<(), Error> {
         self.inner.fresh_connect(enable)

src/easy/handler.rs

@@ -1741,6 +1741,17 @@ impl<H> Easy2<H> {
         self.setopt_long(curl_sys::CURLOPT_MAXCONNECTS, max as c_long)
     }
 
+    /// Set the maximum idle time allowed for a connection.
+    ///
+    /// This configuration sets the maximum time that a connection inside of the connection cache
+    /// can be reused. Any connection older than this value will be considered stale and will
+    /// be closed.
+    ///
+    /// By default, a value of 118 seconds is used.
+    pub fn maxage_conn(&mut self, max_age: Duration) -> Result<(), Error> {
+        self.setopt_long(curl_sys::CURLOPT_MAXAGE_CONN, max_age.as_secs() as c_long)
+    }
+
     /// Force a new connection to be used.
     ///
     /// Makes the next transfer use a new (fresh) connection by force instead of

systest/build.rs

@@ -79,6 +79,7 @@ fn main() {
         if version < 66 {
             match s {
                 "CURL_HTTP_VERSION_3" => return true,
+                "CURLOPT_MAXAGE_CONN" => return true,
                 _ => {}
             }
         }