There is, as far as I can see, only one use of symlink in MediaWiki core. Symlinks are lightweight and ideal, but some systems may not allow them.
Instead of failing outright, an attempt should be made to copy the file and, only if that also fails, declare that the thumbnail creation has failed.
| Subject | Repo | Branch | Lines +/- | |
|---|---|---|---|---|
| Use copy if symlink fails | mediawiki/core | master | +4 -0 |
Change 520347 had a related patch set uploaded (by markahershberger; owner: markahershberger):
[mediawiki/core@master] Use copy if symlink fails
Change 520347 merged by jenkins-bot:
[mediawiki/core@master] Use copy if symlink fails
I have just encountered this issue. I can see in SvgHandler.php that you are attempting to Fallback because symlink often fails on Windows from a symlink() call to a copy() call, but this does not seem to be working. I think the symlink() call throws an exception in this case (not even sure PHP has exceptions), whereas your code is testing the return value of symlink(). According to the documentation for symlink() it sounds like it returns an error value in cases where the link already exists or the target does not exist. It (I guess) does not return an error value but throws an exception on permission denied. For me, when this happens, I get a 500 error from a normal PC, and the following error from the server:
PHP Warning: symlink(): Permission denied in \includes\media\SvgHandler.php on line 313
This is version 1.41.
I was able to correct the issue just by replacing the symlink() call with a copy() call but thought I should report this after seeing the other copy() call that was already there in an attempt to fix this.
I suppose maybe you should try to catch an exception from the symlink() call as well as test the return value, but I am not a PHP dev so am not exactly sure what that would look like.