;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                                                              ;;
;; Copyright (C) KolibriOS team 2004-2015. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License    ;;
;;                                                              ;;
;; Synhronization for MenuetOS.                                 ;;
;; Author: Halyavin Andrey, halyavin@land.ru                    ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

$Revision$



RWSEM_WAITING_FOR_WRITE equ 0
RWSEM_WAITING_FOR_READ  equ 1

;void  __fastcall mutex_init(struct mutex *lock)

align 4
mutex_init:
        mov     [ecx+MUTEX.wait_list.next], ecx
        mov     [ecx+MUTEX.wait_list.prev], ecx
        mov     [ecx+MUTEX.count], 1
        ret

;void  __fastcall mutex_lock(struct mutex *lock)

align 4
mutex_lock:

        dec     [ecx+MUTEX.count]
        jns     .done

        pushfd
        cli

        sub     esp, sizeof.MUTEX_WAITER

        list_add_tail esp, ecx      ;esp= new waiter, ecx= list head

        mov     edx, [TASK_BASE]
        mov     [esp+MUTEX_WAITER.task], edx

.forever:

        mov     eax, -1
        xchg    eax, [ecx+MUTEX.count]
        dec     eax
        jz      @F

        mov     [edx+TASKDATA.state], 1
        call    change_task
        jmp     .forever
@@:
        mov     eax, ecx
        list_del esp

        cmp     [eax+MUTEX.wait_list.next], eax
        jne     @F

        mov     [eax+MUTEX.count], 0
@@:
        add     esp, sizeof.MUTEX_WAITER

        popfd
.done:
        ret

;void  __fastcall mutex_unlock(struct mutex *lock)

align 4
mutex_unlock:

        pushfd
        cli

        mov     eax, [ecx+MUTEX.wait_list.next]
        cmp     eax, ecx
        mov     [ecx+MUTEX.count], 1
        je      @F

        mov     eax, [eax+MUTEX_WAITER.task]
        mov     [eax+TASKDATA.state], 0
@@:
        popfd
        ret


;void __fastcall init_rwsem(struct rw_semaphore *sem)

align 4
init_rwsem:
        mov     [ecx+RWSEM.wait_list.next], ecx
        mov     [ecx+RWSEM.wait_list.prev], ecx
        mov     [ecx+RWSEM.count], 0
        ret

;void __fastcall down_read(struct rw_semaphore *sem)

align 4
down_read:
        pushfd
        cli

        mov     eax, [ecx+RWSEM.count]
        test    eax, eax
        js      @F

        cmp     ecx, [ecx+RWSEM.wait_list.next]
        je      .ok
@@:
        sub     esp, sizeof.MUTEX_WAITER

        mov     eax, [TASK_BASE]
        mov     [esp+MUTEX_WAITER.task], eax
        mov     [esp+MUTEX_WAITER.type], RWSEM_WAITING_FOR_READ
        mov     [eax+TASKDATA.state], 1

        list_add_tail esp, ecx      ;esp= new waiter, ecx= list head

        call    change_task

        add     esp, sizeof.MUTEX_WAITER
        popfd
        ret
.ok:
        inc     eax
        mov     [ecx+RWSEM.count], eax

        popfd
        ret

;void __fastcall down_write(struct rw_semaphore *sem)

align 4
down_write:
        pushfd
        cli
        sub     esp, sizeof.MUTEX_WAITER

        mov     edx, [TASK_BASE]
        mov     [esp+MUTEX_WAITER.task], edx
        mov     [esp+MUTEX_WAITER.type], RWSEM_WAITING_FOR_WRITE
        mov     [edx+TASKDATA.state], 1

        list_add_tail esp, ecx      ;esp= new waiter, ecx= list head

        xor     eax, eax
        not     eax

.forever:
        test    eax, [ecx+RWSEM.count]
        jz      @F

        mov     [edx+TASKDATA.state], 1
        call    change_task
        jmp     .forever
@@:
        mov     [ecx+RWSEM.count], eax
        list_del esp

        add     esp, sizeof.MUTEX_WAITER
        popfd
        ret

;void __fastcall up_read(struct rw_semaphore *sem)

align 4
up_read:
        pushfd
        cli

        dec     [ecx+RWSEM.count]
        jnz     @F

        mov     eax, [ecx+RWSEM.wait_list.next]
        cmp     eax, ecx
        je      @F

        mov     eax, [eax+MUTEX_WAITER.task]
        mov     [eax+TASKDATA.state], 0
@@:
        popfd
        ret

;void __fastcall up_write(struct rw_semaphore *sem)

align 4
up_write:

        pushfd
        cli

        mov     eax, [ecx+RWSEM.wait_list.next]
        mov     [ecx+RWSEM.count], 0

        cmp     ecx, eax
        je      .done

        mov     edx, [eax+MUTEX_WAITER.type]
        test    edx, edx
        jnz     .wake

        mov     eax, [eax+MUTEX_WAITER.task]
        mov     [eax+TASKDATA.state], 0
.done:
        popfd
        ret

.wake:
        push    ebx
        push    esi
        push    edi

        xor     esi, esi
        mov     edi, ecx

.wake_list:

        mov     ebx, [eax+MUTEX_WAITER.list.next]
        list_del eax
        mov     edx, [eax+MUTEX_WAITER.task]
        mov     [edx+TASKDATA.state], 0
        inc     esi
        cmp     edi, ebx
        je      .wake_done

        mov     ecx, [ebx+MUTEX_WAITER.type]
        test    ecx, ecx
        jz      .wake_done

        mov     eax, ebx
        jmp     .wake_list

.wake_done:
        add     [edi+RWSEM.count], esi

        pop     edi
        pop     esi
        pop     ebx
        popfd
        ret


purge RWSEM_WAITING_FOR_WRITE
purge RWSEM_WAITING_FOR_READ


if ~defined sync_inc
sync_inc_fix:
sync_inc fix sync_inc_fix

;simplest mutex.
macro SimpleMutex name
{
;  iglobal
    name dd 0
    name#.type = 1
;  endg
}
macro WaitSimpleMutex name
{
  local start_wait,ok
start_wait=$
        cli
        cmp     [name], dword 0
        jz      ok
        sti
        call    change_task
        jmp     start_wait
ok=$
        push    eax
        mov     eax, dword [TASK_BASE+second_base_address]
        mov     eax, [eax+TASKDATA.pid]
        mov     [name], eax
        pop     eax
        sti
}
macro ReleaseSimpleMutex name
{
        mov     [name], dword 0
}
macro TryWaitSimpleMutex name  ;result in eax and in flags
{
  local ok,try_end
        cmp     [name], dword 0
        jz      ok
        xor     eax, eax
        jmp     try_end
ok=$
        xor     eax, eax
        inc     eax
try_end=$
}
macro SimpleCriticalSection name
{
;  iglobal
    name  dd 0
          dd 0
    name#.type=2
;  endg
}
macro WaitSimpleCriticalSection name
{
  local start_wait,first_wait,inc_counter,end_wait
        push    eax
        mov     eax, [TASK_BASE+second_base_address]
        mov     eax, [eax+TASKDATA.pid]
start_wait=$
        cli
        cmp     [name], dword 0
        jz      first_wait
        cmp     [name], eax
        jz      inc_counter
        sti
        call    change_task
        jmp     start_wait
first_wait=$
        mov     [name], eax
        mov     [name+4], dword 1
        jmp     end_wait
inc_counter=$
        inc     dword [name+4]
end_wait=$
        sti
        pop     eax
}
macro ReleaseSimpleCriticalSection name
{
  local release_end
        dec     dword [name+4]
        jnz     release_end
        mov     [name], dword 0
release_end=$
}
macro TryWaitSimpleCriticalSection name ;result in eax and in flags
{
  local ok,try_end
        mov     eax, [CURRENT_TASK+second_base_address]
        mov     eax, [eax+TASKDATA.pid]
        cmp     [name], eax
        jz      ok
        cmp     [name], 0
        jz      ok
        xor     eax, eax
        jmp     try_end
ok=$
        xor     eax, eax
        inc     eax
try_end=$
}
_cli equ call MEM_HeapLock
_sti equ call MEM_HeapUnLock
end if