upip: url_open: Reworking error handling to guaranteedly close socket.

upip/upip.py

@@ -117,6 +117,7 @@ def url_open(url):
     addr = ai[0][4]
 
     s = usocket.socket(ai[0][0])
+    try:
         #print("Connect address:", addr)
         s.connect(addr)
 
@@ -131,18 +132,18 @@ def url_open(url):
         l = s.readline()
         protover, status, msg = l.split(None, 2)
         if status != b"200":
-        s.close()
-        exc = ValueError(status)
             if status == b"404" or status == b"301":
-            fatal("Package not found", exc)
-        fatal("Unexpected error querying for package", exc)
+                raise NotFoundError("Package not found")
+            raise ValueError(status)
         while 1:
             l = s.readline()
             if not l:
-            s.close()
-            fatal("Unexpected EOF in HTTP headers", ValueError())
+                raise ValueError("Unexpected EOF in HTTP headers")
             if l == b'\r\n':
                 break
+    except Exception as e:
+        s.close()
+        raise e
 
     return s
 
@@ -215,9 +216,10 @@ def install(to_install, install_path=None):
             if deps:
                 deps = deps.decode("utf-8").split("\n")
                 to_install.extend(deps)
-    except NotFoundError:
-        print("Error: cannot find '%s' package (or server error), packages may be partially installed" \
-            % pkg_spec, file=sys.stderr)
+    except Exception as e:
+        print("Error installing '{}': {}, packages may be partially installed".format(
+                pkg_spec, e),
+            file=sys.stderr)
 
 def get_install_path():
     global install_path