urequests: 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.

urequests/urequests.py

@@ -50,43 +50,48 @@ def request(method, url, data=None, json=None, headers={}, stream=None):
 
     ai = usocket.getaddrinfo(host, port)
     addr = ai[0][-1]
-    s = usocket.socket()
-    s.connect(addr)
-    if proto == "https:":
-        s = ussl.wrap_socket(s, server_hostname=host)
-    s.write(b"%s /%s HTTP/1.0\r\n" % (method, path))
-    if not "Host" in headers:
-        s.write(b"Host: %s\r\n" % host)
-    # Iterate over keys to avoid tuple alloc
-    for k in headers:
-        s.write(k)
-        s.write(b": ")
-        s.write(headers[k])
-        s.write(b"\r\n")
-    if json is not None:
-        assert data is None
-        import ujson
-        data = ujson.dumps(json)
-    if data:
-        s.write(b"Content-Length: %d\r\n" % len(data))
-    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:
+    s = usocket.socket()
+    try:
+        s.connect(addr)
+        if proto == "https:":
+            s = ussl.wrap_socket(s, server_hostname=host)
+        s.write(b"%s /%s HTTP/1.0\r\n" % (method, path))
+        if not "Host" in headers:
+            s.write(b"Host: %s\r\n" % host)
+        # Iterate over keys to avoid tuple alloc
+        for k in headers:
+            s.write(k)
+            s.write(b": ")
+            s.write(headers[k])
+            s.write(b"\r\n")
+        if json is not None:
+            assert data is None
+            import ujson
+            data = ujson.dumps(json)
+        if data:
+            s.write(b"Content-Length: %d\r\n" % len(data))
+        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:") and not 200 <= status <= 299:
-            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:") and not 200 <= status <= 299:
+                raise NotImplementedError("Redirects not yet supported")
+    except OSError:
+        s.close()
+        raise
 
     resp = Response(s)
     resp.status_code = status