ptos/amd64+ke: Add system call groundwork + exit syscall

Signed-off-by: Chloe M. <chloe@mensia.org>

service/ptos/head/arch/amd64/trap.h

@@ -28,6 +28,7 @@
 #define TRAP_STACK_SEG_FAULT    0x0C
 #define TRAP_GENERAL_PROTECTION 0x0D
 #define TRAP_PAGE_FAULT         0x0E
+#define TRAP_SYSCALL            0x2E
 
 /* Prototypes of trap functions */
 VOID TrapDivError(VOID);

service/ptos/head/ke/syscall.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: System calls
+ * Author:      Chloe M.
+ */
+
+#ifndef _KE_SYSCALL_H_
+#define _KE_SYSCALL_H_ 1
+
+#include <ptapi/status.h>
+#include <ptapi/syscall.h>
+#include <ptdef.h>
+
+/*
+ * System call arguments passed to system call handlers
+ */
+typedef struct {
+    UQUAD Arg[6];
+} SYSCALL_ARGS;
+
+extern PT_STATUS(*SystemCallTable[_SYSCALL_MAX])(SYSCALL_ARGS *Args);
+
+#endif  /* !_KE_SYSCALL_H_ */

service/ptos/head/ps/uapi.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Process related user-API
+ * Author:      Chloe M.
+ */
+
+#ifndef _PS_UAPI_H_
+#define _PS_UAPI_H_ 1
+
+#include <ps/thread.h>
+#include <ke/syscall.h>
+
+/*
+ * Exit the current thread:
+ *
+ * @ARG[0]:  Exit status code
+ */
+PT_STATUS PsSysThreadExit(SYSCALL_ARGS *Args);
+
+#endif  /* !_PS_UAPI_H_ */