uit_func.inl

ecos为实时嵌入式操作系统

#ifndef CYGONCE_COMPAT_UITRON_UIT_FUNC_INL
#define CYGONCE_COMPAT_UITRON_UIT_FUNC_INL
//===========================================================================
//
//      uit_func.inl
//
//      uITRON compatibility functions
//
//===========================================================================
//####COPYRIGHTBEGIN####
//
// -------------------------------------------
// The contents of this file are subject to the Cygnus eCos Public License
// Version 1.0 (the "License"); you may not use this file except in
// compliance with the License.  You may obtain a copy of the License at
// http://sourceware.cygnus.com/ecos
// 
// Software distributed under the License is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the
// License for the specific language governing rights and limitations under
// the License.
// 
// The Original Code is eCos - Embedded Cygnus Operating System, released
// September 30, 1998.
// 
// The Initial Developer of the Original Code is Cygnus.  Portions created
// by Cygnus are Copyright (C) 1998,1999 Cygnus Solutions.  All Rights Reserved.
// -------------------------------------------
//
//####COPYRIGHTEND####
//===========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   hmt
// Contributors:        hmt
// Date:        1998-03-13
// Purpose:     uITRON compatibility functions
// Description: 
//
//####DESCRIPTIONEND####
//
//===========================================================================

#ifdef CYGPKG_UITRON

#ifdef CYGPRI_UITRON_FUNCS_HERE_AND_NOW

#include <cyg/compat/uitron/uit_objs.hxx> // uITRON setup CYGNUM_UITRON_SEMAS

// kernel facilities only needed here
#include <cyg/kernel/intr.hxx>
#include <cyg/kernel/sched.hxx>

// and the implementations of other kernel facilities
#include <cyg/kernel/thread.inl>
#include <cyg/kernel/sched.inl>
#include <cyg/kernel/clock.inl>


// ------------------------------------------------------------------------
// The variable where dis_dsp/ena_dsp state is held:
extern cyg_uint32 cyg_uitron_dis_dsp_old_priority;

// ------------------------------------------------------------------------
// Parameter checking; either check the expression and return an error code
// if not true, or assert the truth with a made-up message.

#ifdef CYGSEM_UITRON_BAD_PARAMS_RETURN_ERRORS
// default: uitron error codes are returned
#define CYG_UIT_PARAMCHECK( _true_, _error_ ) CYG_MACRO_START           \
    if ( ! (_true_) ) return (_error_);                                 \
CYG_MACRO_END
#else
// ...but they are asserted if asserts are on
#define CYG_UIT_PARAMCHECK( _true_, _error_ ) CYG_MACRO_START           \
    CYG_ASSERT( (_true_), "CYG_UIT_PARAMCHECK fail: " #_true_ );        \
CYG_MACRO_END
#endif // else !CYGSEM_UITRON_BAD_PARAMS_RETURN_ERRORS

// ------------------------------------------------------------------------
// CYG_UITRON_CHECK_AND_GETP
// 
// Macro to rangecheck and do the addressing of a static uitron system
// object; _which_ sort of object is given, and token pasting is used
// horribly to get the static array, limits and the like.
//
// Usage:
//   INT snd_msg( ID mbxid, ... ) {
//      Cyg_Mbox *p;
//      CYG_UITRON_CHECK_AND_GETP_MBOXES( mbxid, p );
//      p->...(...);

// internal: plain assignment to the object pointer, from static array
#define CYG_UIT_SPTR( _which_, _idx_, _ptr_ ) CYG_MACRO_START           \
        (_ptr_) =  CYG_UITRON_OBJS( _which_ ) + ((_idx_) - 1);          \
CYG_MACRO_END

// internal: plain assignment to the object pointer, from pointer array
// with error checking.
#define CYG_UIT_SPTR_PTR( _which_, _idx_, _ptr_ ) CYG_MACRO_START       \
        (_ptr_) =  CYG_UITRON_PTRS( _which_ )[ ((_idx_) - 1) ];         \
        if ( NULL == (_ptr_) ) return E_NOEXS;                          \
CYG_MACRO_END

#define CYG_UITRON_CHECK_AND_GETP_DIRECT( _which_, _idx_, _ptr_ )       \
CYG_MACRO_START                                                         \
    CYG_UIT_PARAMCHECK( 0 < (_idx_), E_ID );                            \
    CYG_UIT_PARAMCHECK( CYG_UITRON_NUM( _which_ ) >= (_idx_), E_ID );   \
    CYG_UIT_SPTR( _which_, _idx_, _ptr_ );                              \
CYG_MACRO_END

#define CYG_UITRON_CHECK_AND_GETP_INDIRECT( _which_, _idx_, _ptr_ )     \
CYG_MACRO_START                                                         \
    CYG_UIT_PARAMCHECK( 0 < (_idx_), E_ID );                            \
    CYG_UIT_PARAMCHECK( CYG_UITRON_NUM( _which_ ) >= (_idx_), E_ID );   \
    CYG_UIT_SPTR_PTR( _which_, _idx_, _ptr_ );                          \
CYG_MACRO_END

// As above but for handler numbers which return E_PAR when out of range
#define CYG_UITRON_CHECK_AND_GETHDLR( _which_, _num_, _ptr_ )           \
CYG_MACRO_START                                                         \
    CYG_UIT_PARAMCHECK( 0 < (_num_), E_PAR );                           \
    CYG_UIT_PARAMCHECK( CYG_UITRON_NUM( _which_ ) >= (_num_), E_PAR );  \
    CYG_UIT_SPTR( _which_, _num_, _ptr_ );                              \
CYG_MACRO_END

// And a macro to check that creation of an object is OK
#define CYG_UITRON_CHECK_NO_OBJ_LOCK_SCHED( _which_, _idx_ )            \
CYG_MACRO_START                                                         \
    CYG_UIT_PARAMCHECK( 0 < (_idx_), E_ID );                            \
    CYG_UIT_PARAMCHECK( CYG_UITRON_NUM( _which_ ) >= (_idx_), E_ID );   \
    Cyg_Scheduler::lock();                                              \
    if ( NULL != CYG_UITRON_PTRS( _which_ )[ ((_idx_) - 1) ] ) {        \
        Cyg_Scheduler::unlock();                                        \
        return E_OBJ;                                                   \
    }                                                                   \
CYG_MACRO_END

// define a magic new operator in order to call constructors
#define CYG_UITRON_NEWFUNCTION( _class_ )                               \
inline void *operator new(size_t size, _class_ *ptr)                    \
{                                                                       \
    CYG_CHECK_DATA_PTR( ptr, "Bad pointer" );                           \
    return ptr;                                                         \
}

// now configury to support selectable create/delete support ie. an
// array of pointers to the objects themselves.
#ifdef CYGPKG_UITRON_TASKS_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_TASKS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( TASKS, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_TASKS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( TASKS, _idx_, _ptr_ )
#endif

#ifdef CYGPKG_UITRON_SEMAS_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_SEMAS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( SEMAS, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_SEMAS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( SEMAS, _idx_, _ptr_ )
#endif

#ifdef CYGPKG_UITRON_MBOXES_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_MBOXES( _idx_, _ptr_ )                \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( MBOXES, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_MBOXES( _idx_, _ptr_ )                \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( MBOXES, _idx_, _ptr_ )
#endif

#ifdef CYGPKG_UITRON_FLAGS_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_FLAGS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( FLAGS, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_FLAGS( _idx_, _ptr_ )                 \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( FLAGS, _idx_, _ptr_ )
#endif

#ifdef CYGPKG_UITRON_MEMPOOLFIXED_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_MEMPOOLFIXED( _idx_, _ptr_ )          \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( MEMPOOLFIXED, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_MEMPOOLFIXED( _idx_, _ptr_ )          \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( MEMPOOLFIXED, _idx_, _ptr_ )
#endif

#ifdef CYGPKG_UITRON_MEMPOOLVAR_CREATE_DELETE
#define CYG_UITRON_CHECK_AND_GETP_MEMPOOLVAR( _idx_, _ptr_ )            \
    CYG_UITRON_CHECK_AND_GETP_INDIRECT( MEMPOOLVAR, _idx_, _ptr_ )
#else
#define CYG_UITRON_CHECK_AND_GETP_MEMPOOLVAR( _idx_, _ptr_ )            \
    CYG_UITRON_CHECK_AND_GETP_DIRECT( MEMPOOLVAR, _idx_, _ptr_ )
#endif

// ------------------------------------------------------------------------
// Common error checking macros

#if !defined( CYGSEM_UITRON_BAD_PARAMS_RETURN_ERRORS ) && \
    !defined( CYGDBG_USE_ASSERTS )
// if not checking and not asserted, these are removed to avoid usused
// variable warnings.
#define CYG_UITRON_CHECK_TASK_CONTEXT_SELF( _self_ )     CYG_EMPTY_STATEMENT
#define CYG_UITRON_CHECK_TASK_CONTEXT()                  CYG_EMPTY_STATEMENT
#define CYG_UITRON_CHECK_DISPATCH_ENABLED()              CYG_EMPTY_STATEMENT
#define CYG_UITRON_CHECK_DISPATCH_ENABLED_TMO( _tmout_ ) CYG_EMPTY_STATEMENT

#else
// the default:
// Check a task is actually a uITRON task
#define CYG_UITRON_CHECK_TASK_CONTEXT_SELF( _self_ ) CYG_MACRO_START    \
    CYG_UIT_PARAMCHECK(                                                 \
        (&cyg_uitron_TASKS[0] <= (_self_)) &&                           \
        ((_self_) < &cyg_uitron_TASKS[CYGNUM_UITRON_TASKS]),            \
                                  E_CTX );                              \
CYG_MACRO_END

#define CYG_UITRON_CHECK_TASK_CONTEXT() CYG_MACRO_START                 \
    Cyg_Thread *self = Cyg_Thread::self();                              \
    CYG_UITRON_CHECK_TASK_CONTEXT_SELF( self );                         \
CYG_MACRO_END

// Check dispatching is enabled for calls which might wait
#define CYG_UITRON_CHECK_DISPATCH_ENABLED()  CYG_MACRO_START            \
    CYG_UIT_PARAMCHECK( 0 == cyg_uitron_dis_dsp_old_priority, E_CTX );  \
CYG_MACRO_END

#define CYG_UITRON_CHECK_DISPATCH_ENABLED_TMO(_tmout_)  CYG_MACRO_START \
    CYG_UIT_PARAMCHECK( -1 <= (_tmout_), E_PAR );                       \
    if ( TMO_POL != (_tmout_) )                                         \
        CYG_UITRON_CHECK_DISPATCH_ENABLED();                            \
CYG_MACRO_END

#endif

#ifdef CYGSEM_UITRON_PARAMS_NULL_IS_GOOD_PTR
#define CYG_UIT_PARAMCHECK_PTR( _p_ )   CYG_MACRO_START                 \
        CYG_UIT_PARAMCHECK( NADR != (_p_), E_PAR );                     \
CYG_MACRO_END
#else // do check for NULL
#define CYG_UIT_PARAMCHECK_PTR( _p_ )   CYG_MACRO_START                 \
        CYG_UIT_PARAMCHECK( NADR != (_p_), E_PAR );                     \
        CYG_UIT_PARAMCHECK( NULL != (_p_), E_PAR );                     \
CYG_MACRO_END
#endif // !CYGSEM_UITRON_PARAMS_NULL_IS_GOOD_PTR

// ------------------------------------------------------------------------
// CYG_UITRON_FAIL_RETURN
//
// After a call which waits, it might return with success, or due to a
// timeout or a release wait (a forced escape from the waiting condition).
// This macro examines context and finds out which, then executes a return
// with the correct uITRON condition code.

#define CYG_UITRON_FAIL_RETURN_SELF( _self_ ) CYG_MACRO_START           \
    Cyg_Thread::cyg_reason reason = (_self_)->get_wake_reason();        \
    if ( Cyg_Thread::TIMEOUT  == reason )                               \
        return E_TMOUT;                                                 \
    if ( Cyg_Thread::BREAK    == reason )                               \
        return E_RLWAI;                                                 \
    if ( Cyg_Thread::DESTRUCT == reason )                               \
        return E_DLT;                                                   \
    return E_SYS; /* if no plausible reason was found */                \
CYG_MACRO_END

#define CYG_UITRON_FAIL_RETURN() CYG_MACRO_START                        \
    Cyg_Thread *self = Cyg_Thread::self();                              \
    CYG_UITRON_FAIL_RETURN_SELF( self );                                \
CYG_MACRO_END

// ------------------------------------------------------------------------
// Interrupts disabled?
#define CYG_UITRON_CHECK_CPU_UNLOC()                                    \
    CYG_UIT_PARAMCHECK( (Cyg_Interrupt::interrupts_enabled()), E_CTX )

// ------------------------------------------------------------------------
// the function definitions themselves:

// ******************************************************
// ***    6.5 C Language Interfaces                   ***
// ******************************************************

// - Task Management Functions

#ifdef CYGPKG_UITRON_TASKS_CREATE_DELETE
CYG_UITRON_NEWFUNCTION( Cyg_Thread )

CYG_UIT_FUNC_INLINE
ER
cre_tsk ( ID tskid, T_CTSK *pk_ctsk )
{
    ER ret = E_OK;
    CYG_UIT_PARAMCHECK_PTR( pk_ctsk );
    CYG_UITRON_CHECK_NO_OBJ_LOCK_SCHED( TASKS, tskid );

    Cyg_Thread *p = &(CYG_UITRON_OBJS( TASKS )[ tskid - 1 ]);
    cyg_uint32 state = p->get_state();
    if ( 0 == (state & Cyg_Thread::EXITED) )
        ret = E_OBJ; // how did it get to be running?
    else if ( ((INT)p->get_stack_size()) < pk_ctsk->stksz )
        ret = E_NOMEM; // more stack requested than available
    else {
        CYG_UITRON_PTRS( TASKS )[ tskid - 1 ] =
            new( p ) Cyg_Thread(
                (CYG_ADDRWORD)      pk_ctsk->itskpri,
                (cyg_thread_entry *)pk_ctsk->task,
                (CYG_ADDRWORD)      0,
                // preserve the original name and stack:
#ifdef CYGVAR_KERNEL_THREADS_NAME
                p->get_name(),
#else
                NULL,
#endif
                p->get_stack_base(),
                p->get_stack_size() );
        // but ensure the task state is dormant:
        // (it is not constructed dormant, but suspended)
        p->kill();
        // and record the initial priority outside the task too.
        CYG_UITRON_TASK_INITIAL_PRIORITY( tskid ) = pk_ctsk->itskpri;
    }
    Cyg_Scheduler::unlock();
    return ret;
}

CYG_UIT_FUNC_INLINE
ER
del_tsk ( ID tskid )
{
    Cyg_Thread *p;
    ER ret = E_OK;
    CYG_UITRON_CHECK_AND_GETP_TASKS( tskid, p );
    
    Cyg_Scheduler::lock();
    // deal with the race condition here
    if ( p != CYG_UITRON_PTRS( TASKS )[ tskid - 1 ] ) {
        Cyg_Scheduler::unlock();
        return E_NOEXS;
    }
    cyg_uint32 state = p->get_state();
    if ( state & Cyg_Thread::EXITED )
        // just disconnect the pointer from its object
        CYG_UITRON_PTRS( TASKS )[ tskid - 1 ] = NULL;
    else
        ret = E_OBJ;
    Cyg_Scheduler::unlock();
    return ret;
}
#endif // CYGPKG_UITRON_TASKS_CREATE_DELETE

CYG_UIT_FUNC_INLINE
ER
sta_tsk ( ID tskid, INT stacd )
{
    Cyg_Thread *p;
    ER ret = E_OK;
    CYG_UITRON_CHECK_AND_GETP_TASKS( tskid, p );
    
    Cyg_Scheduler::lock();
    cyg_uint32 state = p->get_state();
#ifdef CYGPKG_UITRON_TASKS_CREATE_DELETE
    // there is a race condition with deleting the task
    // so test it now that we have the scheduler locked
    if ( p != CYG_UITRON_PTRS( TASKS )[ tskid - 1 ] )
        ret = E_NOEXS;
    else // NOTE dangling else to the next line:
#endif
    if ( state & Cyg_Thread::EXITED ) {
        p->reinitialize();
#ifdef CYGIMP_THREAD_PRIORITY
        p->set_priority( CYG_UITRON_TASK_INITIAL_PRIORITY( tskid ) );
#endif
        p->set_entry_data( (CYG_ADDRWORD)stacd );
        p->force_resume();
    }
    else
        ret = E_OBJ;
    Cyg_Scheduler::unlock();
    return ret;
}

CYG_UIT_FUNC_INLINE
void
ext_tsk ( void )
{    
    Cyg_Thread::exit();
}

CYG_UIT_FUNC_INLINE
void
exd_tsk ( void )
{
#ifdef CYGPKG_UITRON_TASKS_CREATE_DELETE
    Cyg_Thread *p;

    Cyg_Scheduler::lock();
    p = Cyg_Thread::self();
    ID tskid = (p - (&cyg_uitron_TASKS[0])) + 1;    
    // just disconnect the pointer from its object
    CYG_UITRON_PTRS( TASKS )[ tskid - 1 ] = NULL;
    // Any associated storage management, and possibly calling the task
    // destructor, is for future versions.
#else
    // do nothing - deletion not supported so just exit...
#endif
    Cyg_Thread::exit();
    // does not return, does unlock the scheduler for us
}

CYG_UIT_FUNC_INLINE
ER
ter_tsk ( ID tskid )
{
    Cyg_Thread *p;
    ER ret = E_OK;
    CYG_UITRON_CHECK_AND_GETP_TASKS( tskid, p );
    CYG_UIT_PARAMCHECK( Cyg_Thread::self() != p, E_OBJ );
    Cyg_Scheduler::lock();
    if ( (0 != (Cyg_Thread::EXITED & p->get_state())) ||
         (Cyg_Thread::EXIT == p->get_wake_reason()) )
        // already dormant
        ret = E_OBJ;
    else {
        p->force_resume(); // let it run
        p->kill(); // and set prio high so it runs RIGHT NOW!!
#ifdef CYGIMP_THREAD_PRIORITY
        p->set_priority( (cyg_priority) 0 );
#endif
    }
    Cyg_Scheduler::unlock();
#ifdef CYGIMP_THREAD_PRIORITY
    if ( (E_OK == ret) && (0 != cyg_uitron_dis_dsp_old_priority) ) {
        // then dispatching is disabled, so our prio is 0 too
        Cyg_Thread::yield(); // so let the dying thread run;
        Cyg_Thread::yield(); // no cost here of making sure.
    }        
#endif
    return ret;
}

CYG_UIT_FUNC_INLINE
ER
dis_dsp ( void )
{
    CYG_UITRON_CHECK_TASK_CONTEXT();
    CYG_UITRON_CHECK_CPU_UNLOC();
    Cyg_Scheduler::lock();
    // Prevent preemption by going up to prio 0
    if ( 0 == cyg_uitron_dis_dsp_old_priority ) {
#ifdef CYGIMP_THREAD_PRIORITY
        Cyg_Thread *p = Cyg_Thread::self();
        cyg_uitron_dis_dsp_old_priority = p->get_priority();
        p->set_priority( 0 );
#else
        cyg_uitron_dis_dsp_old_priority = 1;
#endif
    }
    Cyg_Scheduler::unlock();
    return E_OK;
}

CYG_UIT_FUNC_INLINE