kern
annotate src/syscall.c @ 73:b4b7198986a6
fixed a potential null dereference when deleting a bug in the redblack tree
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Sat, 15 Oct 2011 08:06:10 +0300 |
| parents | 5b29b15c5412 |
| children | 7ff2b4971216 |
| rev | line source |
|---|---|
| nuclear@51 | 1 #include <stdio.h> |
| nuclear@51 | 2 #include "syscall.h" |
| nuclear@51 | 3 #include "intr.h" |
| nuclear@51 | 4 #include "proc.h" |
| nuclear@51 | 5 #include "sched.h" |
| nuclear@51 | 6 #include "timer.h" |
| nuclear@51 | 7 |
| nuclear@51 | 8 static int (*sys_func[NUM_SYSCALLS])(); |
| nuclear@51 | 9 |
| nuclear@52 | 10 static void syscall(int inum); |
| nuclear@51 | 11 |
| nuclear@51 | 12 static int sys_hello(void); |
| nuclear@51 | 13 |
| nuclear@51 | 14 void init_syscall(void) |
| nuclear@51 | 15 { |
| nuclear@51 | 16 sys_func[SYS_HELLO] = sys_hello; |
| nuclear@72 | 17 sys_func[SYS_SLEEP] = sys_sleep; /* timer.c */ |
| nuclear@72 | 18 sys_func[SYS_FORK] = sys_fork; /* proc.c */ |
| nuclear@72 | 19 sys_func[SYS_EXIT] = sys_exit; /* proc.c */ |
| nuclear@72 | 20 sys_func[SYS_WAITPID] = sys_waitpid; /* proc.c */ |
| nuclear@72 | 21 sys_func[SYS_GETPID] = sys_getpid; /* proc.c */ |
| nuclear@72 | 22 sys_func[SYS_GETPPID] = sys_getppid; /* proc.c */ |
| nuclear@51 | 23 |
| nuclear@51 | 24 interrupt(SYSCALL_INT, syscall); |
| nuclear@51 | 25 } |
| nuclear@51 | 26 |
| nuclear@52 | 27 static void syscall(int inum) |
| nuclear@51 | 28 { |
| nuclear@52 | 29 struct intr_frame *frm; |
| nuclear@52 | 30 int idx; |
| nuclear@52 | 31 |
| nuclear@52 | 32 frm = get_intr_frame(); |
| nuclear@52 | 33 idx = frm->regs.eax; |
| nuclear@51 | 34 |
| nuclear@51 | 35 if(idx < 0 || idx >= NUM_SYSCALLS) { |
| nuclear@51 | 36 printf("invalid syscall: %d\n", idx); |
| nuclear@51 | 37 return; |
| nuclear@51 | 38 } |
| nuclear@51 | 39 |
| nuclear@54 | 40 /* the return value goes into the interrupt frame copy of the user's eax |
| nuclear@54 | 41 * so that it'll be restored into eax before returning to userland. |
| nuclear@54 | 42 */ |
| nuclear@51 | 43 frm->regs.eax = sys_func[idx](frm->regs.ebx, frm->regs.ecx, frm->regs.edx, frm->regs.esi, frm->regs.edi); |
| nuclear@72 | 44 |
| nuclear@72 | 45 /* we don't necessarily want to return to the same process |
| nuclear@72 | 46 * might have blocked or exited or whatever, so call schedule |
| nuclear@72 | 47 * to decide what's going to run next. |
| nuclear@72 | 48 */ |
| nuclear@72 | 49 schedule(); |
| nuclear@51 | 50 } |
| nuclear@51 | 51 |
| nuclear@51 | 52 static int sys_hello(void) |
| nuclear@51 | 53 { |
| nuclear@54 | 54 printf("process %d says hello!\n", get_current_pid()); |
| nuclear@51 | 55 return 0; |
| nuclear@51 | 56 } |