As was done in dc77111 for `support-files/CMakeLists.txt`
Do not rely on existence of `CMakeFiles/${target}.dir` directory
existence. It is not there for custom targets in Ninja build.
This regression was introduced in #1131 which likely copied the pattern
from e79e840 before that regression was addressed in dc77111.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services.
There are many filesystem related errors that can occur with
MariaBackup. These already outputed to stderr with a good description of
the error. Many of these are permission or resource (file descriptor)
limits where the assertion and resulting core crash doesn't offer
developers anything more than the log message. To the user, assertions
and core crashes come across as poor error handling.
As such we return an error and handle this all the way up the stack.
Remove ONLY_IF clause in MYSQL_ADD_PLUGIN and the requirement
that every plugin's CMakeLists.txt *must* do MYSQL_ADD_PLUGIN
for PLUGIN_XXX=YES to work. This was very fragile and cannot be
relied on.
Use a different implementation of =YES check - iterate all
PLUGIN_* variables and see which one doesn't have a matching target.
Revert all ONLY_IF changes in CMakeLists.txt files.