sched_releasetcb() will normally free the stack allocated for a task. However, a task with a custom, user-managed stack may be created using nxtask_init() followed by nxtask_activer. If such a custom stack is used then it must not be free in this many or a crash will most likely result.
This chagne addes a flag call TCB_FLAG_CUSTOM_STACK that may be passed in the the pre-allocted TCB to nxtask_init(). This flag is not used internally anywhere in the OS except that if set, it will prevent sched_releasetcb() from freeing that custom stack.
Add trivial function nxtask_uninit(). This function will undo all operations on a TCB performed by task_init() and release the TCB by calling kmm_free(). This is intended primarily to support error recovery operations after a successful call to task_init() such was when a subsequent call to task_activate fails.
That error recovery is trivial but not obvious. This helper function should eliminate confusion about what to do to recover after calling nxtask_init()
-Move task_init() and task_activate() prototypes from include/sched.h to include/nuttx/sched.h. These are internal OS functions and should not be exposed to the user.
-Remove references to task_init() and task_activate() from the User Manual.
-Rename task_init() to nxtask_init() since since it is an OS internal function
-Rename task_activate() to nxtask_activate since it is an OS internal function
All complaints fixed except for those that were not possible to fix:
- Used of Mixed case identifier in ESP32 files. These are references to Expressif ROM functions which are outside of the scope of NuttX.
Resolution of Issue 619 will require multiple steps, this part of the first step in that resolution: Every call to nxsem_wait_uninterruptible() must handle the return value from nxsem_wait_uninterruptible properly. This commit is only for those files under graphics/, mm/, net/, sched/, wireless/bluetooth.
Still to do: Files under fs/, drivers/, and arch. The last is 116 files and will take some effort.
Move the prototype for the internal OS from from sched/sched/sched.h to include/nuttx/sched.h. This was done because binfmt/binfmt/excecmodule.c requires the prototype for sched_releasetcb() and was illegally including sched/sched/sched.h. That is a blatant violation of the OS modular design and the person that did this should be hung up by their thumbs. Oh... I did that back in a bad moment in 2014. Now that is made right.
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
