http download without Content-Length warns about ending prematurely

[David Johansen]

Summary of the bug:
If the server doesn't provide a Content-Length header, then the handling by libavformat/http.c warns about it ending prematurely when it's actually fine.

How to reproduce:
filesize is -1 so and end_off hasn't been set by a byte range, so the connection ending is incorrectly viewed as ending prematurely, when there's actually no expectation of when it should end.

[Balling]

Is that like when you download in Chrome and it just shows how much you downloaded, but not how much you are left to download?

[David Johansen]

Yes, but that can also be from a streaming response. In this case, it's a non-streaming response but it doesn't have a Content-Length header to indicate how much to download. This isn't common, but can happen if the server doesn't include that header.