rom/task/NextTaskEntry.c

   1 /*
   2     Copyright © 2015-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #define DEBUG 0
   7
   8 #include <aros/debug.h>
   9 #include <exec/types.h>
  10 #include <aros/libcall.h>
  11 #include <proto/utility.h>
  12 #include <resources/task.h>
  13
  14 #include <resources/task.h>
  15
  16 #include "task_intern.h"
  17
  18 /*****************************************************************************
  19
  20     NAME */
  21 #include <proto/task.h>
  22
  23         AROS_LH2(struct Task *, NextTaskEntry,
  24
  25 /*  SYNOPSIS */
  26         AROS_LHA(struct TaskList *, tlist, A0),
  27         AROS_LHA(ULONG           , flags, D0),
  28
  29 /*  LOCATION */
  30         struct TaskResBase *, TaskResBase, 3, Task)
  31
  32 /*  FUNCTION
  33         Looks for the next task list entry with the right type. The list
  34         must be locked for this.
  35
  36     INPUTS
  37         tlist - the value given by LockTaskList()
  38         flags - the same flags as given to LockTaskList() or a subset
  39                 of them.
  40
  41     RESULT
  42         Pointer to task entry found or NULL if the are no more entries.
  43
  44     NOTES
  45
  46     EXAMPLE
  47
  48     BUGS
  49
  50     SEE ALSO
  51         LockTaskList(), UnLockTaskList()
  52
  53     INTERNALS
  54
  55 *****************************************************************************/
  56 {
  57     AROS_LIBFUNC_INIT
  58
  59     struct TaskListPrivate *taskList = (struct TaskListPrivate *)tlist;
  60     struct Task *retVal = NULL;
  61 #ifdef TASKRES_ENABLE
  62     ULONG matchFlags = taskList->tlp_Flags & ~LTF_WRITE;
  63     ULONG matchState = 0;
  64
  65     if (flags)
  66         matchFlags &= flags;
  67 #endif /* TASKRES_ENABLE */
  68
  69     D(bug("[TaskRes] NextTaskEntry: tlist @ 0x%p, flags = $%lx\n", tlist, flags));
  70
  71 #ifdef TASKRES_ENABLE
  72     if (taskList)
  73     {
  74         if (matchFlags & LTF_RUNNING)
  75             matchState |= TS_RUN;
  76
  77         if (matchFlags & LTF_READY)
  78             matchState |= (TS_READY|TS_RUN);
  79
  80         if (matchFlags & LTF_WAITING)
  81             matchState |= (TS_WAIT|TS_SPIN);
  82
  83         while ((taskList->tlp_Next) &&
  84                    ((!taskList->tlp_Next->tle_Task) ||
  85                     (!(taskList->tlp_Next->tle_Task->tc_State & matchState))))
  86         {
  87              taskList->tlp_Next = (struct TaskListEntry *)GetSucc(taskList->tlp_Next);
  88         }
  89
  90         if (taskList->tlp_Next)
  91         {
  92             retVal = taskList->tlp_Next->tle_Task;
  93             taskList->tlp_Next = (struct TaskListEntry *)GetSucc(taskList->tlp_Next);
  94         }
  95     }
  96 #else
  97     if (taskList)
  98     {
  99         if (!taskList->tlp_TaskList)
 100         {
 101             if (flags & LTF_READY)
 102                 taskList->tlp_TaskList = &SysBase->TaskReady;
 103             else if (flags & LTF_WAITING)
 104                 taskList->tlp_TaskList = &SysBase->TaskWait;
 105
 106             return FindTask(NULL);
 107         }
 108         else
 109         {
 110             if (!taskList->tlp_Current)
 111             {
 112                 D(bug("[TaskRes] NextTaskEntry: returning first list entry...\n", tlist, flags));
 113                 if (((taskList->tlp_Current = (struct Task *)GetHead(taskList->tlp_TaskList)) == NULL) &&
 114                     ((flags & LTF_WAITING) && (taskList->tlp_TaskList == &SysBase->TaskReady)))
 115                 {
 116                     taskList->tlp_TaskList = &SysBase->TaskWait;
 117                     taskList->tlp_Current = (struct Task *)GetHead(taskList->tlp_TaskList);
 118                 }
 119             }
 120
 121             if (taskList->tlp_Current)
 122             {
 123                 if ((retVal = (struct Task *)GetSucc(taskList->tlp_Current)) != NULL)
 124                     taskList->tlp_Current = (struct Task *)retVal;
 125                 else if ((flags & LTF_WAITING) && (taskList->tlp_TaskList == &SysBase->TaskReady))
 126                 {
 127                     taskList->tlp_TaskList = &SysBase->TaskWait;
 128                     taskList->tlp_Current = (struct Task *)GetHead(taskList->tlp_TaskList);
 129                 }
 130                 else
 131                     taskList->tlp_Current = NULL;
 132             }
 133         }
 134         retVal = taskList->tlp_Current;
 135     }
 136 #endif /* TASKRES_ENABLE */
 137
 138     return retVal;
 139
 140     AROS_LIBFUNC_EXIT
 141 } /* NextTaskEntry */