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/*
* linux/kernel/signal.c
*
* (C) 1991 Linus Torvalds
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <signal.h>
void do_exit(int error_code);
int sys_sgetmask()
{
return current->blocked;
}
int sys_ssetmask(int newmask)
{
int old=current->blocked;
current->blocked = newmask & ~(1<<(SIGKILL-1));
return old;
}
static inline void save_old(char * from,char * to)
{
int i;
verify_area(to, sizeof(struct sigaction));
for (i=0 ; i< sizeof(struct sigaction) ; i++) {
put_fs_byte(*from,to);
from++;
to++;
}
}
static inline void get_new(char * from,char * to)
{
int i;
for (i=0 ; i< sizeof(struct sigaction) ; i++)
*(to++) = get_fs_byte(from++);
}
int sys_signal(int signum, long handler, long restorer)
{
struct sigaction tmp;
if (signum<1 || signum>32 || signum==SIGKILL)
return -1;
tmp.sa_handler = (void (*)(int)) handler;
tmp.sa_mask = 0;
tmp.sa_flags = SA_ONESHOT | SA_NOMASK;
tmp.sa_restorer = (void (*)(void)) restorer;
handler = (long) current->sigaction[signum-1].sa_handler;
current->sigaction[signum-1] = tmp;
return handler;
}
int sys_sigaction(int signum, const struct sigaction * action,
struct sigaction * oldaction)
{
struct sigaction tmp;
if (signum<1 || signum>32 || signum==SIGKILL)
return -1;
tmp = current->sigaction[signum-1];
get_new((char *) action,
(char *) (signum-1+current->sigaction));
if (oldaction)
save_old((char *) &tmp,(char *) oldaction);
if (current->sigaction[signum-1].sa_flags & SA_NOMASK)
current->sigaction[signum-1].sa_mask = 0;
else
current->sigaction[signum-1].sa_mask |= (1<<(signum-1));
return 0;
}
void do_signal(long signr,long eax, long ebx, long ecx, long edx,
long fs, long es, long ds,
long eip, long cs, long eflags,
unsigned long * esp, long ss)
{
unsigned long sa_handler;
long old_eip=eip;
struct sigaction * sa = current->sigaction + signr - 1;
int longs;
unsigned long * tmp_esp;
sa_handler = (unsigned long) sa->sa_handler;
if (sa_handler==1)
return;
if (!sa_handler) {
if (signr==SIGCHLD)
return;
else
do_exit(1<<(signr-1));
}
if (sa->sa_flags & SA_ONESHOT)
sa->sa_handler = NULL;
*(&eip) = sa_handler;
longs = (sa->sa_flags & SA_NOMASK)?7:8;
*(&esp) -= longs;
verify_area(esp,longs*4);
tmp_esp=esp;
put_fs_long((long) sa->sa_restorer,tmp_esp++);
put_fs_long(signr,tmp_esp++);
if (!(sa->sa_flags & SA_NOMASK))
put_fs_long(current->blocked,tmp_esp++);
put_fs_long(eax,tmp_esp++);
put_fs_long(ecx,tmp_esp++);
put_fs_long(edx,tmp_esp++);
put_fs_long(eflags,tmp_esp++);
put_fs_long(old_eip,tmp_esp++);
current->blocked |= sa->sa_mask;
}
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