std: change tcp_*_result to use result::result.. flatter!

src/libstd/net_tcp.rs

@@ -4,9 +4,12 @@ High-level interface to libuv's TCP functionality
 
 import ip = net_ip;
 
-export tcp_err_data, tcp_connect_result, tcp_write_result, tcp_read_start_result;
+export tcp_socket, tcp_err_data;
-export connect, write;
+export connect, write, read_start, read_stop;
 
+#[doc="
+Encapsulates an open TCP/IP connection through libuv
+"]
 resource tcp_socket(socket_data: @tcp_socket_data) unsafe {
     let closed_po = comm::port::<()>();
     let closed_ch = comm::chan(closed_po);
@@ -26,42 +29,14 @@ resource tcp_socket(socket_data: @tcp_socket_data) unsafe {
     log(debug, "exiting dtor for tcp_socket");
 }
 
+#[doc="
+Contains raw, string-based, error information returned from libuv
+"]
 type tcp_err_data = {
     err_name: str,
     err_msg: str
 };
 
-iface to_tcp_err_iface {
-    fn to_tcp_err() -> tcp_err_data;
-}
-
-impl of to_tcp_err_iface for uv::ll::uv_err_data {
-    fn to_tcp_err() -> tcp_err_data {
-        { err_name: self.err_name, err_msg: self.err_msg }
-    }
-}
-
-enum tcp_connect_result {
-    tcp_connected(tcp_socket),
-    tcp_connect_error(tcp_err_data)
-}
-
-enum tcp_write_result {
-    tcp_write_success,
-    tcp_write_error(tcp_err_data)
-}
-
-enum tcp_read_start_result {
-    tcp_read_start_success(comm::port<tcp_read_result>),
-    tcp_read_start_error(tcp_err_data)
-}
-
-enum tcp_read_result {
-    tcp_read_data([u8]),
-    tcp_read_done,
-    tcp_read_err(tcp_err_data)
-}
-
 #[doc="
 Initiate a client connection over TCP/IP
 
@@ -72,10 +47,12 @@ Initiate a client connection over TCP/IP
 
 # Returns
 
-A `tcp_connect_result` that can be used to determine the connection and,
+A `result` that, if the operation succeeds, contains a `tcp_socket` that
-if successful, send and receive data to/from the remote host
+can be used to send and receive data to/from the remote host. In the event
+of failure, a `tcp_err_data` will be returned
 "]
-fn connect(input_ip: ip::ip_addr, port: uint) -> tcp_connect_result unsafe {
+fn connect(input_ip: ip::ip_addr, port: uint)
+    -> result::result<tcp_socket, tcp_err_data> unsafe {
     let result_po = comm::port::<conn_attempt>();
     let closed_signal_po = comm::port::<()>();
     let conn_data = {
@@ -84,7 +61,7 @@ fn connect(input_ip: ip::ip_addr, port: uint) -> tcp_connect_result unsafe {
     };
     let conn_data_ptr = ptr::addr_of(conn_data);
     let hl_loop = uv::global_loop::get();
-    let reader_po = comm::port::<tcp_read_result>();
+    let reader_po = comm::port::<result::result<[u8], tcp_err_data>>();
     let socket_data = @{
         reader_po: reader_po,
         reader_ch: comm::chan(reader_po),
@@ -161,21 +138,32 @@ fn connect(input_ip: ip::ip_addr, port: uint) -> tcp_connect_result unsafe {
     alt comm::recv(result_po) {
       conn_success {
         log(debug, "tcp::connect - received success on result_po");
-        tcp_connected(tcp_socket(socket_data))
+        result::ok(tcp_socket(socket_data))
       }
       conn_failure(err_data) {
         comm::recv(closed_signal_po);
         log(debug, "tcp::connect - received failure on result_po");
-        tcp_connect_error(err_data.to_tcp_err())
+        result::err(err_data.to_tcp_err())
       }
     }
 }
 
 #[doc="
 Write binary data to a tcp stream
+
+# Arguments
+
+* sock - a `tcp_socket` to write to
+* raw_write_data - a vector of `[u8]` that will be written to the stream.
+This value must remain valid for the duration of the `write` call
+
+# Returns
+
+A `result` object with a `()` value, in the event of success, or a
+`tcp_err_data` value in the event of failure
 "]
-fn write(sock: tcp_socket, raw_write_data: [[u8]]) -> tcp_write_result
+fn write(sock: tcp_socket, raw_write_data: [[u8]])
-    unsafe {
+    -> result::result<(), tcp_err_data> unsafe {
     let socket_data_ptr = ptr::addr_of(**sock);
     let write_req_ptr = ptr::addr_of((*socket_data_ptr).write_req);
     let stream_handle_ptr =
@@ -208,12 +196,28 @@ fn write(sock: tcp_socket, raw_write_data: [[u8]]) -> tcp_write_result
           }
         }
     };
-    comm::recv(result_po)
+    alt comm::recv(result_po) {
+      tcp_write_success { result::ok(()) }
+      tcp_write_error(err_data) { result::err(err_data.to_tcp_err()) }
+    }
 }
 
 #[doc="
+Begin reading binary data from an open TCP connection.
+
+# Arguments
+
+* sock -- a `tcp_socket` for the connection to read from
+
+# Returns
+
+* A `result` instance that will either contain a
+`comm::port<tcp_read_result>` that the user can read (and optionally, loop
+on) from until `read_stop` is called, or a `tcp_err_data` record
 "]
-fn read_start(sock: tcp_socket) -> tcp_read_start_result unsafe {
+fn read_start(sock: tcp_socket)
+    -> result::result<comm::port<
+        result::result<[u8], tcp_err_data>>, tcp_err_data> unsafe {
     let stream_handle_ptr = ptr::addr_of((**sock).stream_handle);
     let start_po = comm::port::<option<uv::ll::uv_err_data>>();
     let start_ch = comm::chan(start_po);
@@ -235,15 +239,19 @@ fn read_start(sock: tcp_socket) -> tcp_read_start_result unsafe {
     };
     alt comm::recv(start_po) {
       some(err_data) {
-        tcp_read_start_error(err_data.to_tcp_err())
+        result::err(err_data.to_tcp_err())
       }
       none {
-        tcp_read_start_success((**sock).reader_po)
+        result::ok((**sock).reader_po)
       }
     }
 }
 
-fn read_stop(sock: tcp_socket) -> option<uv::ll::uv_err_data> unsafe {
+#[doc="
+Stop reading from an open TCP connection.
+"]
+fn read_stop(sock: tcp_socket) ->
+    result::result<(), tcp_err_data> unsafe {
     let stream_handle_ptr = ptr::addr_of((**sock).stream_handle);
     let stop_po = comm::port::<option<tcp_err_data>>();
     let stop_ch = comm::chan(stop_po);
@@ -261,10 +269,49 @@ fn read_stop(sock: tcp_socket) -> option<uv::ll::uv_err_data> unsafe {
           }
         }
     };
-    comm::recv(stop_po)
+    alt comm::recv(stop_po) {
+      some(err_data) {
+        result::err(err_data.to_tcp_err())
+      }
+      none {
+        result::ok(())
+      }
+    }
 }
 
 // INTERNAL API
+
+enum tcp_connect_result {
+    tcp_connected(tcp_socket),
+    tcp_connect_error(tcp_err_data)
+}
+
+enum tcp_write_result {
+    tcp_write_success,
+    tcp_write_error(tcp_err_data)
+}
+
+enum tcp_read_start_result {
+    tcp_read_start_success(comm::port<tcp_read_result>),
+    tcp_read_start_error(tcp_err_data)
+}
+
+enum tcp_read_result {
+    tcp_read_data([u8]),
+    tcp_read_done,
+    tcp_read_err(tcp_err_data)
+}
+
+iface to_tcp_err_iface {
+    fn to_tcp_err() -> tcp_err_data;
+}
+
+impl of to_tcp_err_iface for uv::ll::uv_err_data {
+    fn to_tcp_err() -> tcp_err_data {
+        { err_name: self.err_name, err_msg: self.err_msg }
+    }
+}
+
 crust fn on_tcp_read_cb(stream: *uv::ll::uv_stream_t,
                     nread: libc::ssize_t,
                     ++buf: uv::ll::uv_buf_t) unsafe {
@@ -276,7 +323,7 @@ crust fn on_tcp_read_cb(stream: *uv::ll::uv_stream_t,
       // incoming err.. probably eof
       -1 {
         let err_data = uv::ll::get_last_err_data(loop_ptr);
-        comm::send(reader_ch, tcp_read_err(err_data));
+        comm::send(reader_ch, result::err(err_data.to_tcp_err()));
       }
       // do nothing .. unneeded buf
       0 {}
@@ -287,7 +334,7 @@ crust fn on_tcp_read_cb(stream: *uv::ll::uv_stream_t,
         let buf_base = uv::ll::get_base_from_buf(buf);
         let buf_len = uv::ll::get_len_from_buf(buf);
         let new_bytes = vec::unsafe::from_buf(buf_base, buf_len);
-        comm::send(reader_ch, tcp_read_data(new_bytes));
+        comm::send(reader_ch, result::ok(new_bytes));
       }
     }
     uv::ll::free_base_of_buf(buf);
@@ -391,8 +438,8 @@ enum conn_attempt {
 }
 
 type tcp_socket_data = {
-    reader_po: comm::port<tcp_read_result>,
+    reader_po: comm::port<result::result<[u8], tcp_err_data>>,
-    reader_ch: comm::chan<tcp_read_result>,
+    reader_ch: comm::chan<result::result<[u8], tcp_err_data>>,
     stream_handle: uv::ll::uv_tcp_t,
     connect_req: uv::ll::uv_connect_t,
     write_req: uv::ll::uv_write_t,
@@ -405,10 +452,14 @@ fn ipv4_ip_addr_to_sockaddr_in(input: ip::ip_addr,
     uv::ll::ip4_addr(ip::format_addr(input), port as int)
 }
 
-#[cfg(test)]
+//#[cfg(test)]
 mod test {
     #[test]
     fn test_gl_tcp_ipv4_request() {
+        impl_gl_tcp_ipv4_request();
+    }
+    fn impl_gl_tcp_ipv4_request() {
+        // pre-connection/input data
         let ip_str = "173.194.79.99";
         let port = 80u;
         let expected_read_msg = "foo";
@@ -418,79 +469,76 @@ mod test {
         let data_po = comm::port::<[u8]>();
         let data_ch = comm::chan(data_po);
 
-        alt connect(host_ip, port) {
+        // connect to remote host
-          tcp_connected(sock) {
+        let connect_result = connect(host_ip, port);
-            log(debug, "successful tcp connect");
+        if result::is_failure(connect_result) {
-            let mut write_data: [[u8]] = [];
+            let err_data = result::get_err(connect_result);
-            let write_data = [str::as_bytes(actual_write_msg) {|str_bytes|
+            log(debug, "tcp_connect_error received..");
-                str_bytes
+            log(debug, #fmt("tcp connect error: %? %?", err_data.err_name,
-            }];
-            alt write(sock, write_data) {
-              tcp_write_success {
-                log(debug, "tcp::write successful");
-                let mut total_read_data: [u8] = [];
-                alt read_start(sock) {
-                  tcp_read_start_success(reader_po) {
-                    loop {
-                        alt comm::recv(reader_po) {
-                          tcp_read_data(new_data) {
-                            total_read_data += new_data;
-                            // theoretically, we could keep iterating, if
-                            // we expect the server on the other end to keep
-                            // streaming/chunking data to us, but..
-                            alt read_stop(sock) {
-                              some(err_data) {
-                                log(debug, "error while calling read_stop");
-                                log(debug, #fmt("read_stop error: %? %?",
-                                                err_data.err_name,
                            err_data.err_msg));
             assert false;
         }
-                              none {
+
-                                // exiting the read loop
+        // this is our tcp_socket resource instance. It's dtor will
-                                break;
+        // clean-up/close the underlying TCP stream when the fn scope
+        // ends
+        let sock = result::unwrap(connect_result);
+        log(debug, "successful tcp connect");
+
+        // set up write data
+        let write_data = [str::as_bytes(actual_write_msg) {|str_bytes|
+            str_bytes
+        }];
+
+        // write data to tcp socket
+        let write_result = write(sock, write_data);
+        if result::is_failure(write_result) {
+            let err_data = result::get_err(write_result);
+            log(debug, "tcp_write_error received..");
+            log(debug, #fmt("tcp write error: %? %?", err_data.err_name,
+                           err_data.err_msg));
+            assert false;
         }
+        log(debug, "tcp::write successful");
+
+        // set up read data
+        let mut total_read_data: [u8] = [];
+        let read_start_result = read_start(sock);
+        if result::is_failure(read_start_result) {
+            let err_data = result::get_err(read_start_result);
+            log(debug, "tcp read_start err received..");
+            log(debug, #fmt("read_start error: %? %?", err_data.err_name,
+                           err_data.err_msg));
+            assert false;
         }
-                          }
+        let reader_po = result::get(read_start_result);
-                          tcp_read_done {
+        loop {
-                            break;
+            let read_data_result = comm::recv(reader_po);
-                          }
+            if result::is_failure(read_data_result) {
-                          tcp_read_err(err_data) {
+                let err_data = result::get_err(read_data_result);
                 log(debug, "read error data recv'd");
                 log(debug, #fmt("read error: %? %?",
                                 err_data.err_name,
                                 err_data.err_msg));
                 assert false;
             }
-                        }
+            let new_data = result::unwrap(read_data_result);
-                    }
+            total_read_data += new_data;
-                    comm::send(data_ch, total_read_data);
+            // theoretically, we could keep iterating, if
-                  }
+            // we expect the server on the other end to keep
-                  tcp_read_start_error(err_data) {
+            // streaming/chunking data to us, but..
-                    log(debug, "tcp_read_start_error received..");
+            let read_stop_result = read_stop(sock);
-                    log(debug, #fmt("tcp read_start error: %? %?",
+            if result::is_failure(read_stop_result) {
+                let err_data = result::get_err(read_stop_result);
+                log(debug, "error while calling read_stop");
+                log(debug, #fmt("read_stop error: %? %?",
                                 err_data.err_name,
                                 err_data.err_msg));
                 assert false;
             }
+            break;
         }
-              }
+        comm::send(data_ch, total_read_data);
-              tcp_write_error(err_data) {
-                log(debug, "tcp_write_error received..");
-                log(debug, #fmt("tcp write error: %? %?", err_data.err_name,
-                               err_data.err_msg));
-                assert false;
-              }
-            }
-          }
-          tcp_connect_error(err_data) {
-            log(debug, "tcp_connect_error received..");
-            log(debug, #fmt("tcp connect error: %? %?", err_data.err_name,
-                           err_data.err_msg));
-            assert false;
-          }
-        }
-
         let actual_data = comm::recv(data_po);
         let resp = str::from_bytes(actual_data);
         log(debug, "DATA RECEIVED: "+resp);