with FreeBSD (not including the MINSIGSTKSZ issue, which belongs to
Marcel). Due to time constraints, I'm going to space them out over a
few days.
This fixes two problems with linux_sigaltstack()
o ss == 0 is perfectly valid use, so do not fail in this case.
o Fix flag handling:
- Our SS_DISABLE is 4, linux's is 2, so we need conversion routines.
These conversion routines will be needed by linux_rt_sendsig()
and linux_rt_sigreturn (forthcoming), so they are not static.
- Linux's flag 0 historically meant SS_ONSTACK according to a comment
in their linux/kernel/signal.c file.
Among other things, this fixes a warning from Sun's JDK 1.3:
"Java HotSpot(TM) Client VM warning: cannot uninstall alt signal stack"
Reviewed by: marcel
Tested by: sto@stat.duke.edu, many others on freebsd-java@