urllib.urequest: If error happens while parsing response headers, close socket.

Because otherwise, user doesn't get any response object, so cannot close
socket, and it leaks.

urllib.urequest/urllib/urequest.py

@@ -22,39 +22,44 @@ def urlopen(url, data=None, method="GET"):
 
     ai = usocket.getaddrinfo(host, port)
     addr = ai[0][4]
+
     s = usocket.socket()
-    s.connect(addr)
-    if proto == "https:":
-        s = ussl.wrap_socket(s, server_hostname=host)
+    try:
+        s.connect(addr)
+        if proto == "https:":
+            s = ussl.wrap_socket(s, server_hostname=host)
 
-    s.write(method)
-    s.write(b" /")
-    s.write(path)
-    s.write(b" HTTP/1.0\r\nHost: ")
-    s.write(host)
-    s.write(b"\r\n")
-
-    if data:
-        s.write(b"Content-Length: ")
-        s.write(str(len(data)))
+        s.write(method)
+        s.write(b" /")
+        s.write(path)
+        s.write(b" HTTP/1.0\r\nHost: ")
+        s.write(host)
         s.write(b"\r\n")
-    s.write(b"\r\n")
-    if data:
-        s.write(data)
 
-    l = s.readline()
-    protover, status, msg = l.split(None, 2)
-    status = int(status)
-    #print(protover, status, msg)
-    while True:
+        if data:
+            s.write(b"Content-Length: ")
+            s.write(str(len(data)))
+            s.write(b"\r\n")
+        s.write(b"\r\n")
+        if data:
+            s.write(data)
+
         l = s.readline()
-        if not l or l == b"\r\n":
-            break
-        #print(l)
-        if l.startswith(b"Transfer-Encoding:"):
-            if b"chunked" in l:
-                raise ValueError("Unsupported " + l)
-        elif l.startswith(b"Location:"):
-            raise NotImplementedError("Redirects not yet supported")
+        protover, status, msg = l.split(None, 2)
+        status = int(status)
+        #print(protover, status, msg)
+        while True:
+            l = s.readline()
+            if not l or l == b"\r\n":
+                break
+            #print(l)
+            if l.startswith(b"Transfer-Encoding:"):
+                if b"chunked" in l:
+                    raise ValueError("Unsupported " + l)
+            elif l.startswith(b"Location:"):
+                raise NotImplementedError("Redirects not yet supported")
+    except OSError:
+        s.close()
+        raise
 
     return s