diff options
Diffstat (limited to 'nuttx/sched/errno_getptr.c')
| -rw-r--r-- | nuttx/sched/errno_getptr.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/nuttx/sched/errno_getptr.c b/nuttx/sched/errno_getptr.c index b233b18e4..76123468d 100644 --- a/nuttx/sched/errno_getptr.c +++ b/nuttx/sched/errno_getptr.c @@ -1,7 +1,7 @@ /**************************************************************************** * sched/errno_getptr.c * - * Copyright (C) 2007, 2008, 2011 Gregory Nutt. All rights reserved. + * Copyright (C) 2007, 2008, 2011, 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt <gnutt@nuttx.org> * * Redistribution and use in source and binary forms, with or without @@ -54,6 +54,12 @@ * Private Data ****************************************************************************/ +/* This is a 'dummy' errno value to use in context where there is no valid + * errno location to use. For example, when running from an interrupt handler + * or early in initialization when task structures have not yet been + * initialized. + */ + static int g_irqerrno; /**************************************************************************** @@ -89,10 +95,14 @@ FAR int *get_errno_ptr(void) * task at the head of the ready-to-run list is actually running. It * may not be running during very brief times during context switching * logic (see, for example, task_exit.c). + * + * There is also a corner case early in the initialization sequence: + * The ready to run list may not yet be initialized and g_readytorun.head + * may be NULL. */ FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head; - if (rtcb->task_state == TSTATE_TASK_RUNNING) + if (rtcb && rtcb->task_state == TSTATE_TASK_RUNNING) { /* Yes.. the task is running normally. Return a reference to the * thread-private errno in the TCB of the running task. @@ -113,5 +123,3 @@ FAR int *get_errno_ptr(void) return &g_irqerrno; } - - |