From 1cbd21ded760ffb33c8a2f16d05c574e58166148 Mon Sep 17 00:00:00 2001
From: deadwood <deadwood@fb15a70f-31f2-0310-bbcc-cdcc74a49acc>
Date: Fri, 1 Aug 2014 16:06:20 +0000
Subject: [PATCH] exec.library: implement GetParentTaskStorageSlot()

git-svn-id: https://svn.aros.org/svn/aros/trunk/AROS@49201 fb15a70f-31f2-0310-bbcc-cdcc74a49acc
---
 rom/exec/exec.conf                  |  1 +
 rom/exec/getparenttaskstorageslot.c | 66 +++++++++++++++++++++++++++++++++++++
 rom/exec/gettaskstorageslot.c       | 19 +++++++----
 rom/exec/mmakefile.src              |  3 +-
 rom/exec/settaskstorageslot.c       |  2 ++
 rom/exec/taskstorage.h              |  4 ++-
 6 files changed, 86 insertions(+), 9 deletions(-)
 create mode 100644 rom/exec/getparenttaskstorageslot.c

diff --git a/rom/exec/exec.conf b/rom/exec/exec.conf
index 6497eaf1c9..4c534f7a35 100644
--- a/rom/exec/exec.conf
+++ b/rom/exec/exec.conf
@@ -268,4 +268,5 @@ APTR SaveTaskStorage() ()
 void RestoreTaskStorage(APTR id) (A0)
 BOOL SetTaskStorageSlot(LONG id, IPTR value) (D0, D1)
 IPTR GetTaskStorageSlot(LONG id) (D0)
+IPTR GetParentTaskStorageSlot(LONG id) (D0)
 ##end functionlist
diff --git a/rom/exec/getparenttaskstorageslot.c b/rom/exec/getparenttaskstorageslot.c
new file mode 100644
index 0000000000..6230da210a
--- /dev/null
+++ b/rom/exec/getparenttaskstorageslot.c
@@ -0,0 +1,66 @@
+/*
+    Copyright © 2014, The AROS Development Team. All rights reserved.
+    $Id$
+*/
+
+#include <aros/debug.h>
+
+#include "taskstorage.h"
+
+/*****************************************************************************
+
+    NAME */
+#include <proto/exec.h>
+
+        AROS_LH1(IPTR, GetParentTaskStorageSlot,
+
+/*  LOCATION */
+        AROS_LHA(LONG, id, D0),
+        struct ExecBase *, SysBase, 186, Exec)
+
+/*  FUNCTION
+        Get a value for a task storage slot of parent task.
+
+    INPUTS
+        id - slot ID returned from AllocTaskStorageSlot().
+
+    RESULT
+        Value stored by SetTaskStorageSlot() on parent task, or
+        (IPTR)NULL if the slot was never used.
+
+    NOTES
+        Since you are accessing value of another task, the value
+        might be invalid/freed by the time this function returns.
+        To be sure value is still valid, call this function under
+        Forbid().
+
+    EXAMPLE
+
+    BUGS
+
+    SEE ALSO
+        AllocTaskStorageSlot(), FreeTaskStorageSlot(), SetTaskStorageSlot(),
+        GetTaskStorageSlot()
+
+    INTERNALS
+
+******************************************************************************/
+{
+    AROS_LIBFUNC_INIT
+
+    struct ETask *et = GetETask(FindTask(NULL));
+    IPTR result = (IPTR)NULL;
+
+    if (!et)
+        return (IPTR)NULL;
+
+    Forbid(); /* Accessing other task's et_TaskStorage */
+
+    result = TaskGetStorageSlot(et->et_Parent, id);
+
+    Permit();
+
+    return result;
+
+    AROS_LIBFUNC_EXIT
+}
diff --git a/rom/exec/gettaskstorageslot.c b/rom/exec/gettaskstorageslot.c
index 5aef24dfbc..9795d2c2c1 100644
--- a/rom/exec/gettaskstorageslot.c
+++ b/rom/exec/gettaskstorageslot.c
@@ -1,5 +1,5 @@
 /*
-    Copyright © 2012, The AROS Development Team. All rights reserved.
+    Copyright © 2012-2014, The AROS Development Team. All rights reserved.
     $Id$
 */
 
@@ -48,24 +48,29 @@
 {
     AROS_LIBFUNC_INIT
 
-    struct ETask *et = GetETask(FindTask(NULL));
+    return TaskGetStorageSlot(FindTask(NULL), id);
+
+    AROS_LIBFUNC_EXIT
+}
+
+IPTR TaskGetStorageSlot(struct Task * t, LONG id)
+{
+    struct ETask *et = GetETask(t);
     IPTR *ts;
 
-    D(bug("GetTaskStorage: %p: Get TaskStorageSlot %d\n", et, id));
+    D(bug("TaskGetStorageSlot: %p: Get TaskGetStorageSlot %d\n", et, id));
 
     if (!et) {
         /* Only ETasks can do this */
-        D(bug("GetTaskStorage: Not an ETask!\n"));
+        D(bug("TaskGetStorageSlot: Not an ETask!\n"));
         return (IPTR)NULL;
     }
 
     ts = et->et_TaskStorage;
     if (ts == NULL || ts[__TS_FIRSTSLOT] <= id) {
-        D(bug("GetTaskStorage: ID %d was not set!\n", id));
+        D(bug("TaskGetStorageSlot: ID %d was not set!\n", id));
         return (IPTR)NULL;
     }
 
     return ts[id];
-
-    AROS_LIBFUNC_EXIT
 }
diff --git a/rom/exec/mmakefile.src b/rom/exec/mmakefile.src
index 1f50e1793e..ebb337fbd7 100644
--- a/rom/exec/mmakefile.src
+++ b/rom/exec/mmakefile.src
@@ -35,7 +35,8 @@ ALL_FUNCTIONS := \
 	newaddtask newminlist avl vnewrawdofmt shutdowna useralert \
 	addresetcallback remresetcallback doresetcallbacks newcreatetaska \
         alloctaskstorageslot freetaskstorageslot savetaskstorage \
-        restoretaskstorage settaskstorageslot gettaskstorageslot
+        restoretaskstorage settaskstorageslot gettaskstorageslot \
+        getparenttaskstorageslot
 
 INIT_FILES := exec_init prepareexecbase
 FILES	   := alertextra alert_cpu systemalert initkicktags intservers \
diff --git a/rom/exec/settaskstorageslot.c b/rom/exec/settaskstorageslot.c
index da31409f94..f95747865a 100644
--- a/rom/exec/settaskstorageslot.c
+++ b/rom/exec/settaskstorageslot.c
@@ -78,6 +78,7 @@
 
         ts[__TS_FIRSTSLOT] = slots;
 
+        /* Replacing of the pointer needs to be atomic due to GetParentTaskStorageSlot() */
         et->et_TaskStorage = ts;
     } else if (ts[__TS_FIRSTSLOT] <= id) {
         IPTR *newts;
@@ -96,6 +97,7 @@
                 (oldslots-1) * sizeof(ts[0]));
         memset(&newts[oldslots], 0, (newslots - oldslots) * sizeof(ts[0]));
 
+        /* Replacing of the pointer needs to be atomic due to GetParentTaskStorageSlot() */
         et->et_TaskStorage = newts;
         FreeMem(ts, oldslots * sizeof(ts[0]));
     }
diff --git a/rom/exec/taskstorage.h b/rom/exec/taskstorage.h
index 4c21ca699a..8cd86d1701 100644
--- a/rom/exec/taskstorage.h
+++ b/rom/exec/taskstorage.h
@@ -1,5 +1,5 @@
 /*
-    Copyright © 2011-2012, The AROS Development Team. All rights reserved.
+    Copyright © 2011-2014, The AROS Development Team. All rights reserved.
     $Id$
 */
 #ifndef TASKSTORAGE_H
@@ -16,4 +16,6 @@ struct TaskStorageFreeSlot
 
 #define __TS_FIRSTSLOT 0
 
+IPTR TaskGetStorageSlot(struct Task * t, LONG id);
+
 #endif /* TASKSTORAGE_H */
-- 
2.11.4.GIT