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#include "userprog/syscall.h"
#include <stdio.h>
#include <syscall-nr.h>
#include "threads/interrupt.h"
#include "threads/thread.h"
#include "threads/init.h"
#include "filesys/filesys.h"
#include "filesys/off_t.h"
static void syscall_handler (struct intr_frame *);
void
syscall_init (void)
{
intr_register_int (0x30, 3, INTR_ON, syscall_handler, "syscall");
}
// cast to TYPE and deref argument N from f->esp
#define INTR_ESP(N, TYPE) *(TYPE *)(f->esp+(4*(N)))
static void
syscall_handler (struct intr_frame *f UNUSED)
{
int syscall_number = INTR_ESP(0, int);
switch (syscall_number) {
case 0:
// halt
power_off ();
break;
case 1:
// exit
break;
case 4:
// create
; // empty statement because c-grammar doesn't allow declarations following labels
printf("kernel: create\n");
char *filename = INTR_ESP(1, char *);
printf("create: read filename '%s'\n", filename);
off_t initial_size = INTR_ESP(2, off_t);
printf("create: read initial_size '%d'\n", initial_size);
f->eax = filesys_create(filename, initial_size);
printf("create: result (%d) put in f->eax\n", f->eax);
break;
case 6:
// open
break;
case 8:
// read
break;
case 9:
// write
printf ("printf: %s", INTR_ESP(2, char *));
break;
case 12:
// close
break;
default:
printf ("kernel: unknown syscall '%d'\n", syscall_number);
break;
}
}
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