Fix #642, synchronous task delete on POSIX

src/os/posix/src/os-impl-tasks.c

@@ -477,6 +477,16 @@ int32 OS_Posix_InternalTaskCreate_Impl(pthread_t *pthr, osal_priority_t priority
         return (OS_ERROR);
     }
 
+    /*
+    ** Set the thread to be joinable by default
+    */
+    return_code = pthread_attr_setdetachstate(&custom_attr, PTHREAD_CREATE_JOINABLE);
+    if (return_code != 0)
+    {
+        OS_DEBUG("pthread_attr_setdetachstate error in OS_TaskCreate: %s\n", strerror(return_code));
+        return (OS_ERROR);
+    }
+
     /*
     ** Test to see if the original main task scheduling priority worked.
     ** If so, then also set the attributes for this task.  Otherwise attributes
@@ -541,12 +551,6 @@ int32 OS_Posix_InternalTaskCreate_Impl(pthread_t *pthr, osal_priority_t priority
      ** Do not treat anything bad that happens after this point as fatal.
      ** The task is running, after all - better to leave well enough alone.
      */
-    return_code = pthread_detach(*pthr);
-    if (return_code != 0)
-    {
-        OS_DEBUG("pthread_detach error in OS_TaskCreate: %s\n", strerror(return_code));
-    }
-
     return_code = pthread_attr_destroy(&custom_attr);
     if (return_code != 0)
     {
@@ -583,6 +587,33 @@ int32 OS_TaskCreate_Impl(const OS_object_token_t *token, uint32 flags)
     return return_code;
 } /* end OS_TaskCreate_Impl */
 
+/*----------------------------------------------------------------
+ *
+ * Function: OS_TaskDetach_Impl
+ *
+ *  Purpose: Implemented per internal OSAL API
+ *           See prototype for argument/return detail
+ *
+ *-----------------------------------------------------------------*/
+int32 OS_TaskDetach_Impl(const OS_object_token_t *token)
+{
+    OS_impl_task_internal_record_t *impl;
+    int                             ret;
+
+    impl = OS_OBJECT_TABLE_GET(OS_impl_task_table, *token);
+
+    ret = pthread_detach(impl->id);
+
+    if (ret != 0)
+    {
+        OS_DEBUG("pthread_detach: Failed on Task ID = %lu, err = %s\n",
+                 OS_ObjectIdToInteger(OS_ObjectIdFromToken(token)), strerror(ret));
+        return OS_ERROR;
+    }
+
+    return OS_SUCCESS;
+}
+
 /*----------------------------------------------------------------
  *
  * Function: OS_TaskMatch_Impl
@@ -616,6 +647,8 @@ int32 OS_TaskMatch_Impl(const OS_object_token_t *token)
 int32 OS_TaskDelete_Impl(const OS_object_token_t *token)
 {
     OS_impl_task_internal_record_t *impl;
+    void *                          retval;
+    int                             ret;
 
     impl = OS_OBJECT_TABLE_GET(OS_impl_task_table, *token);
 
@@ -625,7 +658,35 @@ int32 OS_TaskDelete_Impl(const OS_object_token_t *token)
     ** to cancel here is that the thread ID is invalid because it already exited itself,
     ** and if that is true there is nothing wrong - everything is OK to continue normally.
     */
-    pthread_cancel(impl->id);
+    ret = pthread_cancel(impl->id);
+    if (ret != 0)
+    {
+        OS_DEBUG("pthread_cancel: Failed on Task ID = %lu, err = %s\n",
+                 OS_ObjectIdToInteger(OS_ObjectIdFromToken(token)), strerror(ret));
+
+        /* fall through (will still return OS_SUCCESS) */
+    }
+    else
+    {
+        /*
+         * Note that "pthread_cancel" is a request - and successful return above
+         * only means that the cancellation request is pending.
+         *
+         * pthread_join() will wait until the thread has actually exited.
+         *
+         * This is important for CFE, as task deletion often occurs in
+         * conjunction with an application reload - which means the next
+         * call is likely to be OS_ModuleUnload().  So is critical that all
+         * tasks potentially executing code within that module have actually
+         * been stopped - not just pending cancellation.
+         */
+        ret = pthread_join(impl->id, &retval);
+        if (ret != 0)
+        {
+            OS_DEBUG("pthread_join: Failed on Task ID = %lu, err = %s\n",
+                     OS_ObjectIdToInteger(OS_ObjectIdFromToken(token)), strerror(ret));
+        }
+    }
     return OS_SUCCESS;
 
 } /* end OS_TaskDelete_Impl */
@@ -731,6 +792,17 @@ int32 OS_TaskRegister_Impl(osal_id_t global_task_id)
 {
     int32                return_code;
     OS_U32ValueWrapper_t arg;
+    int                  old_state;
+    int                  old_type;
+
+    /*
+     * Set cancel state=ENABLED, type=DEFERRED
+     * This should be the default for new threads, but
+     * setting explicitly to be sure that a pthread_join()
+     * will work as expected in case this thread is deleted.
+     */
+    pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
+    pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &old_type);
 
     arg.opaque_arg = 0;
     arg.id         = global_task_id;

src/os/posix/src/os-impl-timebase.c

@@ -386,7 +386,7 @@ int32 OS_TimeBaseCreate_Impl(const OS_object_token_t *token)
          */
         for (idx = 0; idx < OS_MAX_TIMEBASES; ++idx)
         {
-            if (OS_ObjectIdDefined(OS_global_timebase_table[idx].active_id) &&
+            if (OS_ObjectIdIsValid(OS_global_timebase_table[idx].active_id) &&
                 OS_impl_timebase_table[idx].assigned_signal != 0)
             {
                 sigaddset(&local->sigset, OS_impl_timebase_table[idx].assigned_signal);

src/os/rtems/src/os-impl-tasks.c

@@ -171,6 +171,20 @@ int32 OS_TaskDelete_Impl(const OS_object_token_t *token)
     return OS_SUCCESS;
 } /* end OS_TaskDelete_Impl */
 
+/*----------------------------------------------------------------
+ *
+ * Function: OS_TaskDetach_Impl
+ *
+ *  Purpose: Implemented per internal OSAL API
+ *           See prototype for argument/return detail
+ *
+ *-----------------------------------------------------------------*/
+int32 OS_TaskDetach_Impl(const OS_object_token_t *token)
+{
+    /* No-op on RTEMS */
+    return OS_SUCCESS;
+}
+
 /*----------------------------------------------------------------
  *
  * Function: OS_TaskExit_Impl

src/os/shared/inc/os-shared-idmap.h

@@ -30,8 +30,6 @@
 
 #include <os-shared-globaldefs.h>
 
-#define OS_OBJECT_EXCL_REQ_FLAG 0x0001
-
 #define OS_OBJECT_ID_RESERVED ((osal_id_t) {0xFFFFFFFF})
 
 /*
@@ -43,7 +41,6 @@ struct OS_common_record
     osal_id_t   active_id;
     osal_id_t   creator;
     uint16      refcount;
-    uint16      flags;
 };
 
 /*
@@ -214,6 +211,26 @@ static inline void OS_ObjectIdCompose_Impl(osal_objtype_t idtype, uint32 idseria
     *result = OS_ObjectIdFromInteger((idtype << OS_OBJECT_TYPE_SHIFT) | idserial);
 }
 
+/*-------------------------------------------------------------------------------------*/
+/**
+ * @brief Check if an object ID represents a valid/active value.
+ *
+ * This tests that the ID value is within the range specifically used by
+ * valid OSAL IDs. This is smaller than the set of defined IDs.
+ *
+ * For example, the value of OS_OBJECT_ID_RESERVED is defined but not valid.
+ * So while OS_ObjectIdDefined() will match entries being actively created or
+ * deleted, OS_ObjectIdIsValid() will not.
+ *
+ * @param[in]   object_id The object ID
+ * @returns     true if table entry is valid
+ */
+static inline bool OS_ObjectIdIsValid(osal_id_t object_id)
+{
+    osal_objtype_t objtype = OS_ObjectIdToType_Impl(object_id);
+    return (objtype > OS_OBJECT_TYPE_UNDEFINED && objtype < OS_OBJECT_TYPE_USER);
+}
+
 /*----------------------------------------------------------------
    Function: OS_GetMaxForObjectType
 

src/os/shared/inc/os-shared-task.h

@@ -94,6 +94,16 @@ int32 OS_TaskMatch_Impl(const OS_object_token_t *token);
  ------------------------------------------------------------------*/
 int32 OS_TaskCreate_Impl(const OS_object_token_t *token, uint32 flags);
 
+/*----------------------------------------------------------------
+   Function: OS_TaskDetach_Impl
+
+    Purpose: Sets the thread so that the OS resources associated with the task
+             will be released when the thread exits itself
+
+    Returns: OS_SUCCESS on success, or relevant error code
+ ------------------------------------------------------------------*/
+int32 OS_TaskDetach_Impl(const OS_object_token_t *token);
+
 /*----------------------------------------------------------------
    Function: OS_TaskDelete_Impl