finally implemented fork() syscall

1 files changed, 38 insertions, 0 deletions

diff --git a/asm/int_syscall_handler.asm b/asm/int_syscall_handler.asm
index 50202d3..89f152b 100644
--- a/asm/int_syscall_handler.asm
+++ b/asm/int_syscall_handler.asm
@@ -1,4 +1,5 @@
 global int_syscall_handler
+[extern task_fork]
 
 [extern syscall_exit]
 [extern syscall_write]
@@ -13,11 +14,18 @@ global int_syscall_handler
 [extern syscall_sbrk]
 [extern syscall_stat]
 [extern syscall_lstat]
+[extern syscall_fork]
 [extern syscall_unhandled]
 
 [bits 32]
+
+pid: dd 0x0
+
 int_syscall_handler:
 
+cmp eax, 72
+je call_fork
+
  cli
 
     push ebx
@@ -63,6 +71,7 @@ int_syscall_handler:
     cmp eax, 79
     je call_lstat
 
+
     push eax
     jmp call_unhandled
 
@@ -89,6 +98,34 @@ done_blocking:
 
     iret           ;Interrupt-Return
 
+call_fork:
+
+    cli
+
+    pusha          ;Push all standard registers
+
+    mov ebx, esp	;save current stack pointer in esp
+    mov esp, 0x7000	;now put the stack outside of virtual memory in kernel space!
+
+    push ebx      ;Push pointer to all the stuff we just pushed
+    call task_fork ;Call C code
+    mov [pid],eax
+
+    mov esp, ebx   ;Replace the stack with what the C code gave us
+    
+    mov al, 0x20   ;Port number AND command number to Acknowledge IRQ
+    out 0x20, al   ;Acknowledge IRQ, so we keep getting interrupts
+
+
+    popa           ;Put the standard registers back
+
+    mov ebx,[pid]
+
+    sti
+
+    iretd           ;Interrupt-Return
+    ;;;;
+
 call_stat:
     call syscall_stat
     jmp done
@@ -139,6 +176,7 @@ call_unhandled:
 
 
     ;;; THIS CALLS NEED REENABLE INTERRUPTS BEFORE calling workers
+    ;; TODO: redesign this shit!
 call_read:
 
     mov al, 0x20   ;Port number AND command number to Acknowledge IRQ