sigaltstack.c

#include "defs.h"
#include "xlat/sigaltstack_flags.h"

static void
print_stack_t(struct tcb *tcp, unsigned long addr)
{
	stack_t ss;

#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
	if (current_wordsize != sizeof(ss.ss_sp) && current_wordsize == 4) {
		struct {
			uint32_t ss_sp;
			int32_t ss_flags;
			uint32_t ss_size;
		} ss32;

		if (umove_or_printaddr(tcp, addr, &ss32))
			return;

		memset(&ss, 0, sizeof(ss));
		ss.ss_sp = (void*)(unsigned long) ss32.ss_sp;
		ss.ss_flags = ss32.ss_flags;
		ss.ss_size = (unsigned long) ss32.ss_size;
	} else
#endif
	if (umove_or_printaddr(tcp, addr, &ss))
		return;

	tprints("{ss_sp=");
	printaddr((unsigned long) ss.ss_sp);
	tprints(", ss_flags=");
	printflags(sigaltstack_flags, ss.ss_flags, "SS_???");
	tprintf(", ss_size=%lu}", (unsigned long) ss.ss_size);
}

SYS_FUNC(sigaltstack)
{
	if (entering(tcp)) {
		print_stack_t(tcp, tcp->u_arg[0]);
		tprints(", ");
	} else {
		print_stack_t(tcp, tcp->u_arg[1]);
	}
	return 0;
}