rom/exec/findtaskbypid.c

   1 /*
   2     Copyright © 1995-2015, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <exec/execbase.h>
   7 #include <exec/tasks.h>
   8
   9 #include "exec_intern.h"
  10
  11 /*****************************************************************************
  12
  13     NAME */
  14 #include <proto/exec.h>
  15
  16         AROS_LH1(struct Task *, FindTaskByPID,
  17
  18 /*  SYNOPSIS */
  19         AROS_LHA(ULONG, id, D0),
  20
  21 /*  LOCATION */
  22         struct ExecBase *, SysBase, 166, Exec)
  23
  24 /*  FUNCTION
  25         Scan through the task lists searching for the task whose
  26         et_UniqueID field matches.
  27
  28     INPUTS
  29         id      -   The task ID to match.
  30
  31     RESULT
  32         Address of the Task control structure that matches, or
  33         NULL otherwise.
  34
  35     NOTES
  36         This function is source-compatible with MorphOS.
  37
  38     EXAMPLE
  39
  40     BUGS
  41
  42     SEE ALSO
  43
  44     INTERNALS
  45
  46 ******************************************************************************/
  47 {
  48     AROS_LIBFUNC_INIT
  49
  50 #if defined(__AROSEXEC_SMP__)
  51     spinlock_t *listLock;
  52 #endif
  53     struct Task *t;
  54     struct ETask *et;
  55
  56     /* First up, check running task(s) */
  57 #if defined(__AROSEXEC_SMP__)
  58     listLock = EXEC_SPINLOCK_LOCK(&PrivExecBase(SysBase)->TaskRunningSpinLock, SPINLOCK_MODE_READ);
  59     Forbid();
  60 #else
  61     Disable();
  62 #endif
  63 #if defined(__AROSEXEC_SMP__)
  64     ForeachNode(&PrivExecBase(SysBase)->TaskRunning, t)
  65     {
  66         et = GetETask(t);
  67         if (et != NULL && et->et_UniqueID == id)
  68         {
  69             EXEC_SPINLOCK_UNLOCK(listLock);
  70             Permit();
  71             return t;
  72         }
  73     }
  74     EXEC_SPINLOCK_UNLOCK(listLock);
  75     Permit();
  76     listLock = EXEC_SPINLOCK_LOCK(&PrivExecBase(SysBase)->TaskReadySpinLock, SPINLOCK_MODE_READ);
  77     Forbid();
  78 #else
  79     if (GET_THIS_TASK != NULL)
  80     {
  81         et = GetETask(GET_THIS_TASK);
  82         if (et != NULL && et->et_UniqueID == id)
  83         {
  84             Enable();
  85             return GET_THIS_TASK;
  86         }
  87     }
  88 #endif
  89     /*  Next, go through the ready list */
  90     ForeachNode(&SysBase->TaskReady, t)
  91     {
  92         et = GetETask(t);
  93         if (et != NULL && et->et_UniqueID == id)
  94         {
  95 #if defined(__AROSEXEC_SMP__)
  96             EXEC_SPINLOCK_UNLOCK(listLock);
  97             Permit();
  98 #else
  99             Enable();
 100 #endif
 101             return t;
 102         }
 103     }
 104 #if defined(__AROSEXEC_SMP__)
 105     EXEC_SPINLOCK_UNLOCK(listLock);
 106     Permit();
 107     listLock = EXEC_SPINLOCK_LOCK(&PrivExecBase(SysBase)->TaskWaitSpinLock, SPINLOCK_MODE_READ);
 108     Forbid();
 109 #endif
 110     /* Finally, go through the wait list */
 111     ForeachNode(&SysBase->TaskWait, t)
 112     {
 113         et = GetETask(t);
 114         if (et != NULL && et->et_UniqueID == id)
 115         {
 116 #if defined(__AROSEXEC_SMP__)
 117             EXEC_SPINLOCK_UNLOCK(listLock);
 118             Permit();
 119 #else
 120             Enable();
 121 #endif
 122             return t;
 123         }
 124     }
 125
 126 #if defined(__AROSEXEC_SMP__)
 127     EXEC_SPINLOCK_UNLOCK(listLock);
 128     Permit();
 129 #else
 130     Enable();
 131 #endif
 132
 133     return NULL;
 134
 135     AROS_LIBFUNC_EXIT
 136 }