[ECOS] What's the meaning of those C++ code? Thanks.

["QiangHuang" <jameshq at liverpool dot ac dot uk>]

Hi all:
   I have tried to understand the following C++ code in eCOS but I can't
find the way out. Could anybody help me on this? Thanks a lot.

//==========================================================================
===============================
file: kapidata.h

struct cyg_mutex_t
{
    cyg_atomic          locked;         /* true if locked               */
    cyg_thread          *owner;         /* Current locking thread       */
    cyg_threadqueue     queue;          /* Queue of waiting threads     */

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC
    cyg_mutex_protocol_t protocol;       /* this mutex's protocol        */
#endif
#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING
    cyg_priority_t      ceiling;        /* mutex priority ceiling       */
#endif
};
//==========================================================================
===============================

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++
file: kapi.cxx

inline void *operator new(size_t size, void *ptr)
{
    CYG_CHECK_DATA_PTR( ptr, "Bad pointer" );
    return ptr;
}


externC void cyg_mutex_init(
    cyg_mutex_t        *mutex          /* Mutex to init
*/
)
{
    CYG_ASSERT_SIZES( cyg_mutex_t, Cyg_Mutex );

    Cyg_Mutex *m = new((void *)mutex) Cyg_Mutex;

    m=m;
}
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++

so when declares:

cyg_mutex_t mutex1;
cyg_mutex_init(&mutex1);

what's the meaning of  "(1). Cyg_Mutex *m = new((void *)mutex) Cyg_Mutex;
(2). m=m;"  here? Thanks a lot.


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