From 6f971a331aef1ab3a8bd1d05bc84a9b04b5ad574 Mon Sep 17 00:00:00 2001
From: pumnflqv2 <ggdxz77@163.com>
Date: Sun, 26 Jun 2022 22:38:27 +0800
Subject: [PATCH] ADD file via upload

---
 kernel/signal.c | 129 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 129 insertions(+)
 create mode 100644 kernel/signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
new file mode 100644
index 0000000..8d5a65f
--- /dev/null
+++ b/kernel/signal.c
@@ -0,0 +1,129 @@
+/*
+ *  linux/kernel/signal.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <asm/segment.h>
+#include <errno.h>
+#include <signal.h>
+
+volatile 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;
+}
+
+int sys_sigpending()
+{
+	return -ENOSYS;
+}
+
+int sys_sigsuspend()
+{
+	return -ENOSYS;
+}
+
+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;
+}