proxy settings: transfer to neon

If proxy settings are turned off in the config, the default system
proxy settings are used. This depends on ne_session_system_proxy(),
introduced in neon 0.29. The version is checked at configure time.  A
fallback if only an older version is found is intentionally not
present yet, the feature is meant to work in all cases.

src/backends/webdav/NeonCXX.cpp

@@ -162,6 +162,14 @@ Session::Session(const boost::shared_ptr<Settings> &settings) :
         }
         ne_ssl_set_clicert(m_session, cert);
     }
+
+    std::string proxyurl = settings->proxy();
+    if (proxyurl.empty()) {
+        ne_session_system_proxy(m_session, 0);
+    } else {
+        URI proxyuri = URI::parse(proxyurl);
+        ne_session_proxy(m_session, proxyuri.m_host.c_str(), proxyuri.m_port);
+    }
 }
 
 Session::~Session()

src/backends/webdav/NeonCXX.h

@@ -50,6 +50,11 @@ class Settings {
      */
     virtual bool verifySSLCertificate() = 0;
 
+    /**
+     * proxy URL, empty for system default
+     */
+    virtual std::string proxy() = 0;
+
     /**
      * fill in username and password for specified realm (URL?),
      * throw error if not available

src/backends/webdav/WebDAVSource.cpp

@@ -82,6 +82,16 @@ public:
         return !m_context || m_context->getSSLVerifyServer();
     }
 
+    virtual std::string proxy()
+    {
+        if (!m_context ||
+            !m_context->getUseProxy()) {
+            return "";
+        } else {
+            return m_context->getProxyHost();
+        }
+    }
+
     virtual bool googleUpdateHack() { return m_googleUpdateHack; }
     virtual bool googleChildHack() { return m_googleChildHack; }
 

src/backends/webdav/configure-sub.in

@@ -11,7 +11,7 @@ AC_ARG_ENABLE_BACKEND(dav,
 
 if test "$enable_dav" = "yes"; then
         PKG_CHECK_MODULES(LIBICAL, libical)
-        PKG_CHECK_MODULES(NEON, neon)
+        PKG_CHECK_MODULES(NEON, neon >= 0.29)
         AC_DEFINE(ENABLE_DAV, 1, [DAV available])
         AC_DEFINE(ENABLE_ICAL, 1, [libical in use])
         BACKEND_CPPFLAGS="$BACKEND_CPPFLAGS $NEON_CFLAGS"