curl: Apply upstream patch to fix https hangs

https://github.com/curl/curl/issues/1174

Fixes https://github.com/NixOS/nix/issues/1181.

pkgs/tools/networking/curl/default.nix

@@ -25,8 +25,12 @@ stdenv.mkDerivation rec {
     sha256 = "16rqhyzlpnivifin8n7l2fr9ihay9v2nw2drsniinb6bcykqaqfi";
   };
 
+  patches = [ ./issue-1174.patch ];
+
   outputs = [ "bin" "dev" "out" "man" "devdoc" ];
 
+  enableParallelBuilding = true;
+
   nativeBuildInputs = [ pkgconfig perl ];
 
   # Zlib and OpenSSL must be propagated because `libcurl.la' contains

pkgs/tools/networking/curl/issue-1174.patch

@@ -0,0 +1,34 @@
+commit a7b38c9dc98481e4a5fc37e51a8690337c674dfb
+Author: Daniel Stenberg <daniel@haxx.se>
+Date:   Mon Dec 26 00:06:33 2016 +0100
+
+    vtls: s/SSLEAY/OPENSSL
+    
+    Fixed an old leftover use of the USE_SSLEAY define which would make a
+    socket get removed from the applications sockets to monitor when the
+    multi_socket API was used, leading to timeouts.
+    
+    Bug: #1174
+
+diff --git a/lib/vtls/vtls.c b/lib/vtls/vtls.c
+index b808e1c..707f24b 100644
+--- a/lib/vtls/vtls.c
++++ b/lib/vtls/vtls.c
+@@ -484,7 +484,7 @@ void Curl_ssl_close_all(struct Curl_easy *data)
+   curlssl_close_all(data);
+ }
+ 
+-#if defined(USE_SSLEAY) || defined(USE_GNUTLS) || defined(USE_SCHANNEL) || \
++#if defined(USE_OPENSSL) || defined(USE_GNUTLS) || defined(USE_SCHANNEL) || \
+     defined(USE_DARWINSSL) || defined(USE_NSS)
+ /* This function is for OpenSSL, GnuTLS, darwinssl, and schannel only. */
+ int Curl_ssl_getsock(struct connectdata *conn, curl_socket_t *socks,
+@@ -518,7 +518,7 @@ int Curl_ssl_getsock(struct connectdata *conn,
+   (void)numsocks;
+   return GETSOCK_BLANK;
+ }
+-/* USE_SSLEAY || USE_GNUTLS || USE_SCHANNEL || USE_DARWINSSL || USE_NSS */
++/* USE_OPENSSL || USE_GNUTLS || USE_SCHANNEL || USE_DARWINSSL || USE_NSS */
+ #endif
+ 
+ void Curl_ssl_close(struct connectdata *conn, int sockindex)