2000-03-04 Mark Kettenis <kettenis@gnu.org>

2000-03-04  Mark Kettenis  <kettenis@gnu.org>

	Fix support for Linux/i386 signal trampolines.  The old approach
	didn't work for Linux 2.2 and beyond, and didn't work with recent
	versions of the GNU C library.
	* i386-tdep.c (LINUX_RT_SIGTRAMP_INSN0, LINUX_RT_SIGTRAMP_OFFSET0,
	LINUX_RT_SIGTRAMP_INSN1, LINUX_RT_SIGTRAMP_OFFSET1): New defines.
	(linux_rt_sigtramp_code): New variable.
	(LINUX_RT_SIGTRAMP_LEN): New define.
	(i386_linux_rt_sigtramp_start): New function.  Detect start of
	signal trampolines for RT signals.
	(i386_linux_sigtramp): Removed.
	(i386_linux_in_sigtramp): New function.
	(i386_linux_sigcontext_addr): New function.  Recognize the names
	of the signal tranmpolines used by recent versions of the GNU C
	library, and add support for RT signals.
        (LINUX_SIGCONTEXT_PC_OFFSET, LINUX_SIGCONTEXT_SP_OFFSET):  New
	defines.  Moved here from config/i386/tm-linux.h.
	(i386_linux_sigtramp_saved_pc, i386_linux_sigtramp_saved_sp):
	Reimplement in terms of i386_linux_sigcontext_addr.
	* config/i386/tm-linux.h (LINUX_SIGCONTEXT_SIZE): Removed.
        (LINUX_SIGCONTEXT_PC_OFFSET, LINUX_SIGCONTEXT_SP_OFFSET):
        Moved to i386-tdep.c.
	(IN_SIGTRAMP): Redefine to call i386_linux_in_sigtramp.