deh: fix parsing of last lines in files without newline at EOF

Chocolate Doom fails to properly parse the last line in DEHACKED files
that are missing a newline character at the end of the file (which
might have been a common sickness to DOS editors).

This is, because DEH_GetChar() returns -1 at EOF and DEH_ReadLine() in
turn immediately returns NULL if the result of (DEH_GetChar() < 0),
regardless of the content of the readbuffer. It only returns a pointer
to the content of the readbuffer if DEH_GetChar() returns '\n' which
is, however, impossible if there is no such character before the file
ends.

Now DEH_ReadLine() only returns NULL if the readbuffer is empty at the
end of the file and returns a valid pointer else.

Fixes #531

0 files changed, 0 insertions, 0 deletions