restore: separate prepare_one_sigaction

Impact: cleaning-up
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/cr-restore.c

@@ -288,40 +288,26 @@ static bool sa_inherited(int sig, rt_sigaction_t *sa)
 		pa->rt_sa_mask.sig[0] == sa->rt_sa_mask.sig[0];
 }
 
-static int prepare_sigactions(void)
+/* Returns number of restored signals, -1 or negative errno on fail */
+static int restore_one_sigaction(int sig, struct cr_img *img, int pid)
 {
-	int pid = current->pid.virt;
 	rt_sigaction_t act;
-	struct cr_img *img;
 	SaEntry *e;
-	int sig, rst = 0;
 	int ret = 0;
 
-	if (!task_alive(current))
-		return 0;
-
-	pr_info("Restore sigacts for %d\n", pid);
-
-	img = open_image(CR_FD_SIGACT, O_RSTR, pid);
-	if (!img)
-		return -1;
-
-	for (sig = 1; sig <= SIGMAX; sig++) {
-		if (sig == SIGKILL || sig == SIGSTOP)
-			continue;
+	BUG_ON(sig == SIGKILL || sig == SIGSTOP);
 
 	ret = pb_read_one_eof(img, &e, PB_SIGACT);
 	if (ret == 0) {
 		if (sig != SIGMAX_OLD + 1) { /* backward compatibility */
 			pr_err("Unexpected EOF %d\n", sig);
-				ret = -1;
-				break;
+			return -1;
 		}
 		pr_warn("This format of sigacts-%d.img is deprecated\n", pid);
-			break;
+		return -1;
 	}
 	if (ret < 0)
-			break;
+		return ret;
 
 	ASSIGN_TYPED(act.rt_sa_handler, decode_pointer(e->sigaction));
 	ASSIGN_TYPED(act.rt_sa_flags, e->flags);
@@ -332,11 +318,11 @@ static int prepare_sigactions(void)
 
 	if (sig == SIGCHLD) {
 		sigchld_act = act;
-			continue;
+		return 0;
 	}
 
 	if (sa_inherited(sig - 1, &act))
-			continue;
+		return 1;
 
 	/*
 	 * A pure syscall is used, because glibc
@@ -345,17 +331,44 @@ static int prepare_sigactions(void)
 	ret = syscall(SYS_rt_sigaction, sig, &act, NULL, sizeof(k_rtsigset_t));
 	if (ret < 0) {
 		pr_perror("Can't restore sigaction");
-			goto err;
+		return ret;
 	}
 
 	parent_act[sig - 1] = act;
+
+	return 1;
+}
+
+static int prepare_sigactions(void)
+{
+	int pid = current->pid.virt;
+	struct cr_img *img;
+	int sig, rst = 0;
+	int ret = 0;
+
+	if (!task_alive(current))
+		return 0;
+
+	pr_info("Restore sigacts for %d\n", pid);
+
+	img = open_image(CR_FD_SIGACT, O_RSTR, pid);
+	if (!img)
+		return -1;
+
+	for (sig = 1; sig <= SIGMAX; sig++) {
+		if (sig == SIGKILL || sig == SIGSTOP)
+			continue;
+
+		ret = restore_one_sigaction(sig, img, pid);
+		if (ret < 0)
+			break;
+		if (ret)
 			rst++;
 	}
 
 	pr_info("Restored %d/%d sigacts\n", rst,
 			SIGMAX - 3 /* KILL, STOP and CHLD */);
 
-err:
 	close_image(img);
 	return ret;
 }