Feat: POSIX signal

kernel/include/process.h

@@ -1,6 +1,8 @@
 #pragma once
 
 #include <stddef.h>
+#include <vector.h>
+#include <signal.h>
 
 typedef struct {
   uint64_t x0, x1;
@@ -38,6 +40,13 @@ typedef struct process {
   void *mem;
   size_t mem_size;
 
+  void *sigstack;
+  size_t sigstack_size;
+
+  bool sigstate[SIGNAL_NUM];
+  int32_t current_signal;
+  signal_handler_t sighandlers[SIGNAL_NUM];
+
   trapframe_t *regs;
 } process_t;
 
@@ -51,3 +60,4 @@ int32_t run_process(uint64_t process);
 process_t *fork_process(const process_t *from);
 
 extern int32_t global_pid_counter;
+extern vector_t *global_processes;

kernel/include/signal.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <stddef.h>
+
+#define SIGNAL_NUM 32
+
+#define SIGKILL 9
+
+typedef void (*signal_handler_t)();
+
+void run_signal(int32_t SIGNAL);

kernel/include/syscall.h

@@ -2,6 +2,7 @@
 
 #include <stddef.h>
 #include <process.h>
+#include <signal.h>
 
 void syscall_handler(trapframe_t *regs);
 
@@ -12,4 +13,7 @@ int32_t sys_exec(const char *name, char *const argv[]);
 int32_t sys_fork(void);
 void sys_exit(int32_t status);
 int32_t sys_mbox_call(uint8_t ch, uint32_t *mbox);
-void sys_kill(int32_t pid);
+void sys_kill_by_id(int32_t pid);
+void sys_signal(int32_t SIGNAL, signal_handler_t handler);
+void sys_kill(int32_t pid, int32_t SIGNAL);
+void sys_sigreturn(void);