feat: part 2 complete

OSs/lab4/part-2/Makefile

@@ -0,0 +1,12 @@
+targets = main
+all: $(targets)
+
+main: main.o
+	$(CC) -o $@ $^ $(CFLAGS)
+
+%.o: %.c
+	$(CC) -c $^ -o $@ $(CFLAGS)
+
+clean:
+	rm -f $(targets)
+	rm -f *.o

OSs/lab4/part-2/main.c

@@ -0,0 +1,43 @@
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
+
+#define SLEEP_TIME 1
+
+volatile int x;
+
+void sigint_handler(int signal)
+{
+    puts("sigint handler");
+    sleep(SLEEP_TIME);
+}
+
+void sigusr1_handler(int signal)
+{
+    puts("sigusr1 handler");
+    kill(getpid(), SIGINT);
+}
+
+#define DO_OR_FAIL(cond) if (cond) return EXIT_FAILURE
+int main()
+{
+    struct sigaction sa_int = {
+        .sa_handler = sigint_handler
+    };
+    struct sigaction sa_usr1 = {
+        .sa_handler = sigusr1_handler
+    };
+    struct sigaction old_sa = {0};
+    DO_OR_FAIL(sigemptyset(&sa_int.sa_mask));
+    DO_OR_FAIL(sigemptyset(&sa_usr1.sa_mask));
+    DO_OR_FAIL(sigaddset(&sa_int.sa_mask, SIGINT));
+    DO_OR_FAIL(sigaddset(&sa_usr1.sa_mask, SIGUSR1));
+    DO_OR_FAIL(sigaction(SIGINT, &sa_int, &old_sa));
+    DO_OR_FAIL(sigaction(SIGUSR1, &sa_usr1, NULL));
+    while (true) {
+        x++; // чтобы не соптимизировался
+    }
+    return EXIT_SUCCESS;
+}