A patch I did back in 2014 modified ast_config_text_file_save2 to check the
writability of the main file and include files before truncating and re-writing
them. An unintended side-effect of this was that if a file doesn't exist,
the check fails and the write is aborted.
This patch causes ast_config_text_file_save2 to check the writability of the
parent directory of missing files instead of checking the file itself. This
allows missing files to be created again. A unit test was also added to
test_config to test saving of config files.
The regression was discovered when app_voicemail's passwordlocation=spooldir
feature stopped working.
ASTERISK-25917 #close
Reported-by: Jonathan Rose
Change-Id: Ic4dbe58c277a47b674679e49daed5fc6de349f80
284bb814ac