Programs that want to background themselves now need
to define threadmaybackground returning 1.
This avoids a confusing (to people and debuggers)
extra parent process for all the threaded programs
that will never want to background themselves.
Remote whitespace at the ends of lines.
Remove blank lines from the ends of files.
Change modes on source files so that they
are not executable.
Signed-off-by: Dan Cross <cross@gajendra.net>
Instead of checking Fcall.data==nil, check Fcall.count==0.
The former check always fails after `gcc -O2` optimizations
(gcc version 8.3.0).
Also fix an out-of-bound read detected by valgrind:
```
==31162== Invalid read of size 1
==31162== at 0x11005E: morerules (rules.c:739)
==31162== by 0x110254: writerules (rules.c:775)
==31162== by 0x10D2FE: fsyswrite (fsys.c:848)
==31162== by 0x10C304: fsysproc (fsys.c:248)
==31162== by 0x112E8C: threadstart (thread.c:96)
==31162== by 0x4A682BF: ??? (in /usr/lib/libc-2.29.so)
==31162== Address 0x4ea984a is 0 bytes after a block of size 250 alloc'd
==31162== at 0x483AD7B: realloc (vg_replace_malloc.c:826)
==31162== by 0x1196F3: p9realloc (malloc.c:53)
==31162== by 0x10BDFD: erealloc (plumber.c:124)
==31162== by 0x10FCD9: concat (rules.c:642)
==31162== by 0x10FCD9: concat (rules.c:635)
==31162== by 0x110230: writerules (rules.c:773)
==31162== by 0x10D2FE: fsyswrite (fsys.c:848)
==31162== by 0x10C304: fsysproc (fsys.c:248)
==31162== by 0x112E8C: threadstart (thread.c:96)
==31162== by 0x4A682BF: ??? (in /usr/lib/libc-2.29.so)
```
Fixes#256
