From 542c8cf9ef310ea8a27ebab948f96595300dcf5a Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Thu, 6 Oct 2016 00:50:55 +0300
Subject: [PATCH] upip: save_file(): Optimize, use inplace buffer.

---
 upip/upip.py | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/upip/upip.py b/upip/upip.py
index a590d2a4..34cd2052 100644
--- a/upip/upip.py
+++ b/upip/upip.py
@@ -11,6 +11,8 @@ DEFAULT_MICROPYPATH = "~/.micropython/lib:/usr/lib/micropython"
 debug = False
 cleanup_files = []
 
+file_buf = bytearray(512)
+
 class NotFoundError(Exception):
     pass
 
@@ -44,13 +46,13 @@ def _makedirs(name, mode=0o777):
 
 
 def save_file(fname, subf):
-    outf = open(fname, "wb")
-    while True:
-        buf = subf.read(1024)
-        if not buf:
-            break
-        outf.write(buf)
-    outf.close()
+    global file_buf
+    with open(fname, "wb") as outf:
+        while True:
+            sz = subf.readinto(file_buf)
+            if not sz:
+                break
+            outf.write(file_buf, sz)
 
 def install_tar(f, prefix):
     meta = {}