1 #include <stdio.h>

2 #include "syscall.h"

3 #include "intr.h"

4 #include "proc.h"

5 #include "sched.h"

6 #include "timer.h"

7

8 static int (*sys_func[NUM_SYSCALLS])();

9

10 static void syscall(int inum);

11

12 static int sys_hello(void);

13 static int sys_sleep(int sec);

14 static int sys_fork(void);

15 static int sys_getpid(void);

16

17 void init_syscall(void)

18 {

19 sys_func[SYS_HELLO] = sys_hello;

20 sys_func[SYS_SLEEP] = sys_sleep;

21 sys_func[SYS_FORK] = sys_fork;

22 sys_func[SYS_GETPID] = sys_getpid;

23

24 interrupt(SYSCALL_INT, syscall);

25 }

26

27 static void syscall(int inum)

28 {

29 struct intr_frame *frm;

30 int idx;

31

32 frm = get_intr_frame();

33 idx = frm->regs.eax;

34

35 if(idx < 0 || idx >= NUM_SYSCALLS) {

36 printf("invalid syscall: %d\n", idx);

37 return;

38 }

39

40 /* the return value goes into the interrupt frame copy of the user's eax

41 * so that it'll be restored into eax before returning to userland.

42 */

43 frm->regs.eax = sys_func[idx](frm->regs.ebx, frm->regs.ecx, frm->regs.edx, frm->regs.esi, frm->regs.edi);

44 }

45

46 static int sys_hello(void)

47 {

48 printf("process %d says hello!\n", get_current_pid());

49 return 0;

50 }

51

52 static int sys_sleep(int sec)

53 {

54 printf("process %d will sleep for %d seconds\n", get_current_pid(), sec);

55 sleep(sec * 1000); /* timer.c */

56 return 0;

57 }

58

59 static int sys_fork(void)

60 {

61 printf("process %d is forking\n", get_current_pid());

62 return fork(); /* proc.c */

63 }

64

65 static int sys_getpid(void)

66 {

67 int pid = get_current_pid();

68 printf("process %d getpid\n", pid);

69 return pid;

70 }