--- a/netwerk/base/rust-url-capi/src/error_mapping.rs
+++ b/netwerk/base/rust-url-capi/src/error_mapping.rs
@@ -1,57 +1,50 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 use url::ParseError;
 
 pub trait ErrorCode {
   fn error_code(&self) -> i32;
 }
 
 impl<T: ErrorCode> ErrorCode for Result<(), T> {
   fn error_code(&self) -> i32 {
     match *self {
       Ok(_) => 0,
       Err(ref error) => error.error_code(),
     }
   }
 }
 
-impl ErrorCode for () {
-    fn error_code(&self) -> i32 {
-        return -1;
+impl ErrorCode for Result<(), ()> {
+  fn error_code(&self) -> i32 {
+    match *self {
+      Ok(_)  =>    0,
+      Err(_) => -255,
     }
+  }
 }
+
 impl ErrorCode for ParseError {
   fn error_code(&self) -> i32 {
-      return -1;
-//    match *self {
-//      ParseError::EmptyHost                              =>  -1,
-//      ParseError::InvalidScheme                          =>  -2,
-//      ParseError::InvalidPort                            =>  -3,
-//      ParseError::InvalidIpv6Address                     =>  -4,
-//      ParseError::InvalidDomainCharacter                 =>  -5,
-//      ParseError::InvalidCharacter                       =>  -6,
-//      ParseError::InvalidBackslash                       =>  -7,
-//      ParseError::InvalidPercentEncoded                  =>  -8,
-//      ParseError::InvalidAtSymbolInUser                  =>  -9,
-//      ParseError::ExpectedTwoSlashes                     => -10,
-//      ParseError::ExpectedInitialSlash                   => -11,
-//      ParseError::NonUrlCodePoint                        => -12,
-//      ParseError::RelativeUrlWithScheme                  => -13,
-//      ParseError::RelativeUrlWithoutBase                 => -14,
-//      ParseError::RelativeUrlWithNonRelativeBase         => -15,
-//      ParseError::NonAsciiDomainsNotSupportedYet         => -16,
-//      ParseError::CannotSetJavascriptFragment            => -17,
-//      ParseError::CannotSetPortWithFileLikeScheme        => -18,
-//      ParseError::CannotSetUsernameWithNonRelativeScheme => -19,
-//      ParseError::CannotSetPasswordWithNonRelativeScheme => -20,
-//      ParseError::CannotSetHostPortWithNonRelativeScheme => -21,
-//      ParseError::CannotSetHostWithNonRelativeScheme     => -22,
-//      ParseError::CannotSetPortWithNonRelativeScheme     => -23,
-//      ParseError::CannotSetPathWithNonRelativeScheme     => -24,
-//    }
+    match *self {
+      ParseError::EmptyHost                              =>  -1,
+      ParseError::InvalidPort                            =>  -2,
+      ParseError::InvalidIpv6Address                     =>  -3,
+      ParseError::InvalidDomainCharacter                 =>  -4,
+      ParseError::IdnaError                              =>  -5,
+      ParseError::InvalidIpv4Address                     =>  -6,
+      ParseError::RelativeUrlWithoutBase                 =>  -7,
+      ParseError::RelativeUrlWithCannotBeABaseBase       =>  -8,
+      ParseError::SetHostOnCannotBeABaseUrl              =>  -9,
+      ParseError::Overflow                               => -10,
+    }
   }
 }
 
 pub enum NSError {
   OK,
   InvalidArg,
   Failure,
 }

--- a/netwerk/base/rust-url-capi/src/lib.rs
+++ b/netwerk/base/rust-url-capi/src/lib.rs
@@ -1,8 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 extern crate url;
 use url::{Url, ParseError, ParseOptions};
 use url::quirks;
 extern crate libc;
 use libc::size_t;
 
 
 use std::mem;
@@ -315,49 +319,53 @@ pub unsafe extern "C" fn rusturl_set_pat
   let mut url: &mut Url = mem::transmute(urlptr);
   let slice = std::slice::from_raw_parts(path as *const libc::c_uchar, len as usize);
 
   let path_ = match str::from_utf8(slice).ok() {
     Some(p) => p,
     None => return ParseError::InvalidDomainCharacter.error_code() // utf-8 failed
   };
 
-  quirks::set_pathname(url, path_).error_code()
+  quirks::set_pathname(url, path_);
+  NSError::OK.error_code()
+
 }
 
 #[no_mangle]
 pub unsafe extern "C" fn rusturl_set_query(urlptr: rusturl_ptr, query: *mut libc::c_char, len: size_t) -> i32 {
   if urlptr.is_null() {
     return NSError::InvalidArg.error_code();
   }
   let mut url: &mut Url = mem::transmute(urlptr);
   let slice = std::slice::from_raw_parts(query as *const libc::c_uchar, len as usize);
 
   let query_ = match str::from_utf8(slice).ok() {
     Some(p) => p,
     None => return ParseError::InvalidDomainCharacter.error_code() // utf-8 failed
   };
 
-  quirks::set_search(url, query_).error_code()
+  quirks::set_search(url, query_);
+  NSError::OK.error_code()
 }
 
 #[no_mangle]
 pub unsafe extern "C" fn rusturl_set_fragment(urlptr: rusturl_ptr, fragment: *mut libc::c_char, len: size_t) -> i32 {
   if urlptr.is_null() {
     return NSError::InvalidArg.error_code();
   }
   let mut url: &mut Url = mem::transmute(urlptr);
   let slice = std::slice::from_raw_parts(fragment as *const libc::c_uchar, len as usize);
 
   let fragment_ = match str::from_utf8(slice).ok() {
     Some(p) => p,
     None => return ParseError::InvalidDomainCharacter.error_code() // utf-8 failed
   };
 
-  quirks::set_hash(url, fragment_).error_code()
+  quirks::set_hash(url, fragment_);
+  NSError::OK.error_code()
 }
 
 #[no_mangle]
 pub unsafe extern "C" fn rusturl_resolve(urlptr: rusturl_ptr, resolve: *mut libc::c_char, len: size_t, cont: *mut libc::c_void) -> i32 {
   if urlptr.is_null() {
     return NSError::InvalidArg.error_code();
   }
   let url: &mut Url = mem::transmute(urlptr);
@@ -470,8 +478,12 @@ pub unsafe extern "C" fn rusturl_relativ
   }
   for p2 in path2 {
     buffer = buffer + p2 + "/";
   }
 
   return cont.assign(&buffer);
 }
 
+#[no_mangle]
+pub unsafe extern "C" fn sizeof_rusturl() -> size_t {
+  mem::size_of::<Url>()
+}

--- a/netwerk/base/rust-url-capi/src/rust-url-capi.h
+++ b/netwerk/base/rust-url-capi/src/rust-url-capi.h
@@ -1,8 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 #ifndef __RUST_URL_CAPI
 #define __RUST_URL_CAPI
 #include <stdlib.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
@@ -33,13 +37,15 @@ int32_t rusturl_set_port_no(rusturl_ptr 
 int32_t rusturl_set_path(rusturl_ptr url, const char *path, size_t len);
 int32_t rusturl_set_query(rusturl_ptr url, const char *path, size_t len);
 int32_t rusturl_set_fragment(rusturl_ptr url, const char *path, size_t len);
 
 int32_t rusturl_resolve(rusturl_ptr url, const char *relative, size_t len, void*);
 int32_t rusturl_common_base_spec(rusturl_ptr url1, rusturl_ptr url2, void*);
 int32_t rusturl_relative_spec(rusturl_ptr url1, rusturl_ptr url2, void*);
 
+size_t sizeof_rusturl();
+
 #ifdef __cplusplus
 }
 #endif
 
-#endif // __RUST_URL_CAPI
\ No newline at end of file
+#endif // __RUST_URL_CAPI

--- a/netwerk/base/rust-url-capi/src/string_utils.rs
+++ b/netwerk/base/rust-url-capi/src/string_utils.rs
@@ -1,8 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 extern crate libc;
 use libc::size_t;
 
 extern crate std;
 use std::ptr;
 
 use error_mapping::*;
 

--- a/netwerk/base/rust-url-capi/test/test.cpp
+++ b/netwerk/base/rust-url-capi/test/test.cpp
@@ -1,8 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>
 #include "../src/rust-url-capi.h"
 
 class StringContainer
 {
 public: