xv6/syscall.c
2006-06-15 16:02:20 +00:00

50 lines
755 B
C

#include "types.h"
#include "param.h"
#include "mmu.h"
#include "proc.h"
#include "defs.h"
#include "x86.h"
#include "traps.h"
#include "syscall.h"
/*
* User code makes a system call with INT T_SYSCALL.
* System call number in %eax.
* Arguments on the stack.
*
* Return value? Error indication? Errno?
*/
void
sys_fork()
{
newproc();
}
void
sys_exit()
{
curproc->state = UNUSED;
// XXX free resources. notify parent. abandon children.
swtch();
}
void
syscall()
{
int num = curproc->tf->tf_regs.reg_eax;
cprintf("%x sys %d\n", curproc, num);
switch(num){
case SYS_fork:
sys_fork();
break;
case SYS_exit:
sys_exit();
break;
default:
cprintf("unknown sys call %d\n", num);
// XXX fault
break;
}
}