Build without unrar

[Legimet]

Chromium includes unrar (used by Safe Browsing) and it seems that the same is true of CEF - I ran "strings" on the debug build of libcef.so and found numerous filenames from the unrar source code.

Unfortunately unrar is released under a license that is considered nonfree and GPL-incompatible. Many GNU/Linux distributions such as Debian and Fedora remove it from the builds of Chromium. GPL-incompatibility would mean that the official build of CEF can't be used by a GPL'd application.

For this reason, Chromium recently added a build option to disable the use of unrar. Would it be possible for CEF to use this option?

Actually, is there any reason for Safe Browsing to be included in CEF? Why not just build with "safe_browsing_mode=0"?

[magreenblatt]

GPL-incompatibility would mean that the official build of CEF can't be used by a GPL'd application.

CEF is distributed in binary form, as a shared library. In that form it can be used by an application with any license (including closed source).

From the commit message:

The license of unrar is considered incompatible with DFSG / OSI OSD
(rule 6), and FSF FSD (freedom 0). Some distros follow that strictly
and maintain patches to remove it independently. This CL upstreams it
as a simple build option.

This is an idealogical, not legal, issue.

is there any reason for Safe Browsing to be included in CEF?

We’ll look into it.

[magreenblatt]

Related to safe browsing: https://github.com/ungoogled-software/u ... /issues/50

We’re going to keep it enabled by default. You can create custom builds of CEF/Chromium if you wish to disable it.

[Czarek]

Found unrar license in Chromium sources:
https://source.chromium.org/chromium/ch ... %20license

Looks OK to me.

Winrar license != unrar license.

[Legimet]

GPL-incompatibility would mean that the official build of CEF can't be used by a GPL'd application.

CEF is distributed in binary form, as a shared library. In that form it can be used by an application with any license (including closed source).

From the commit message:

The license of unrar is considered incompatible with DFSG / OSI OSD
(rule 6), and FSF FSD (freedom 0). Some distros follow that strictly
and maintain patches to remove it independently. This CL upstreams it
as a simple build option.

This is an idealogical, not legal, issue.

Sorry, forgot about this. I guess I worded my post badly. As far as Debian/Fedora's removal of unrar, you are right that this is ideological, not legal, as the unrar license is of course compatible with the BSD license of Chromium.

But it is in fact a legal issue for anyone who wants to use the official build of CEF and a GPL-licensed library in the same application, or release a GPL-licensed application using CEF, because the license of unrar is GPL-incompatible due to a usage restriction. It does not matter whether one uses dynamic or static linking, because the GPL treats both scenarios the same. Unrar and GPL code cannot be combined, legally speaking.

Of course, I or anyone else could make their own unrar-free builds of CEF. But the GPL is a very commonly used license so I think it would be good if the official build were GPL-compatible. I know of at least two popular open source applications that have this issue, and I doubt the developers are even aware of it.

Looks OK to me.

Winrar license != unrar license.

Yeah that's the license I'm referring to. It has the line: "cannot be used to develop RAR (WinRAR) compatible archiver and to re-create RAR compression algorithm, which is proprietary." This is a usage restriction, which makes it GPL-incompatible.

[magreenblatt]

Thanks for the clarification. You’re correct that this unrar clause may apply to applications using CEF:

cannot be used to re-create the RAR compression algorithm […] may not be used to develop a RAR (WinRAR) compatible archiver.

In which case this may make the CEF binaries that include unrar incompatible with GPL-licensed derivative products.