Retry downloads if a server doesn't support byte ranges

If an incomplete download exists, and the HTTP server doesn't support
byte ranges, delete the incomplete download and retry once.

Tested with freeling, whose server does not support byte ranges.

Closes Homebrew/homebrew#19757.

1 files changed, 11 insertions, 1 deletions

diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index d1564f977..67261af2a 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -69,10 +69,20 @@ class CurlDownloadStrategy < AbstractDownloadStrategy
 
     ohai "Downloading #{@url}"
     unless @tarball_path.exist?
+      had_incomplete_download = @temporary_path.exist?
       begin
         _fetch
       rescue ErrorDuringExecution
-        raise CurlDownloadStrategyError, "Download failed: #{@url}"
+        # 33 == range not supported
+        # try wiping the incomplete download and retrying once
+        if $?.exitstatus == 33 && had_incomplete_download
+          ohai "Trying a full download"
+          @temporary_path.unlink
+          had_incomplete_download = false
+          retry
+        else
+          raise CurlDownloadStrategyError, "Download failed: #{@url}"
+        end
       end
       ignore_interrupts { @temporary_path.rename(@tarball_path) }
     else