From d7d2a9a3dbf1cef78c5085a4aab5d2f336c64cff Mon Sep 17 00:00:00 2001
From: remitamine <remitamine@gmail.com>
Date: Sun, 2 Aug 2015 03:28:04 +0100
Subject: [PATCH] [utils] restart download if server does not support byte
 ranges

---
 youtube_dl/downloader/http.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/youtube_dl/downloader/http.py b/youtube_dl/downloader/http.py
index b7f144af9e..b2e82cfde3 100644
--- a/youtube_dl/downloader/http.py
+++ b/youtube_dl/downloader/http.py
@@ -57,6 +57,20 @@ class HttpFD(FileDownloader):
             # Establish connection
             try:
                 data = self.ydl.urlopen(request)
+
+                if resume_len > 0:
+                    content_range = data.headers.get('Content-Range')
+                    if content_range:
+                        content_range_m = re.search(r'bytes (\d+)-', content_range)
+                        if content_range_m:
+                            # Content-Range is correct - go on
+                            if resume_len == int(content_range_m.group(1)):
+                                break
+
+                    # Content-Range is invalid - wipe the file and do entire redownload
+                    resume_len = 0
+                    open_mode = 'wb'
+
                 break
             except (compat_urllib_error.HTTPError, ) as err:
                 if (err.code < 500 or err.code >= 600) and err.code != 416: