syscall.c

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/*------------------------------------------------------------------------*/
/* Sample code of OS dependent controls for FatFs                         */
/* (C)ChaN, 2014                                                          */
/*------------------------------------------------------------------------*/



#include "user_config.h"
#include "fatfs.h"

#ifdef AVR
#include <stdlib.h>
#endif

#include "fatfs/ff.h"                                   /* Declarations of FatFs API */



#if _FS_REENTRANT
/*------------------------------------------------------------------------*/
/* Create a Synchronization Object
/*------------------------------------------------------------------------*/
/* This function is called in f_mount() function to create a new
/  synchronization object, such as semaphore and mutex. When a 0 is returned,
/  the f_mount() function fails with FR_INT_ERR.
*/


MEMSPACE
int ff_cre_syncobj (    /* 1:Function succeeded, 0:Could not create the sync object */
    BYTE vol,           /* Corresponding volume (logical drive number) */
    _SYNC_t *sobj       /* Pointer to return the created sync object */
)
{
    int ret;


    *sobj = CreateMutex(NULL, FALSE, NULL);     /* Win32 */
    ret = (int)(*sobj != INVALID_HANDLE_VALUE);

//  *sobj = SyncObjects[vol];           /* uITRON (give a static sync object) */
//  ret = 1;                            /* The initial value of the semaphore must be 1. */

//  *sobj = OSMutexCreate(0, &err);     /* uC/OS-II */
//  ret = (int)(err == OS_NO_ERR);

//  *sobj = xSemaphoreCreateMutex();    /* FreeRTOS */
//  ret = (int)(*sobj != NULL);

    return ret;
}



/*------------------------------------------------------------------------*/
/* Delete a Synchronization Object                                        */
/*------------------------------------------------------------------------*/
/* This function is called in f_mount() function to delete a synchronization
/  object that created with ff_cre_syncobj() function. When a 0 is returned,
/  the f_mount() function fails with FR_INT_ERR.
*/

MEMSPACE
int ff_del_syncobj (    /* 1:Function succeeded, 0:Could not delete due to any error */
    _SYNC_t sobj        /* Sync object tied to the logical drive to be deleted */
)
{
    int ret;


    ret = CloseHandle(sobj);    /* Win32 */

//  ret = 1;                    /* uITRON (nothing to do) */

//  OSMutexDel(sobj, OS_DEL_ALWAYS, &err);  /* uC/OS-II */
//  ret = (int)(err == OS_NO_ERR);

//  vSemaphoreDelete(sobj);     /* FreeRTOS */
//  ret = 1;

    return ret;
}



/*------------------------------------------------------------------------*/
/* Request Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on entering file functions to lock the volume.
/  When a 0 is returned, the file function fails with FR_TIMEOUT.
*/

MEMSPACE
int ff_req_grant (  /* 1:Got a grant to access the volume, 0:Could not get a grant */
    _SYNC_t sobj    /* Sync object to wait */
)
{
    int ret;

    ret = (int)(WaitForSingleObject(sobj, _FS_TIMEOUT) == WAIT_OBJECT_0);   /* Win32 */

//  ret = (int)(wai_sem(sobj) == E_OK);         /* uITRON */

//  OSMutexPend(sobj, _FS_TIMEOUT, &err));      /* uC/OS-II */
//  ret = (int)(err == OS_NO_ERR);

//  ret = (int)(xSemaphoreTake(sobj, _FS_TIMEOUT) == pdTRUE);   /* FreeRTOS */

    return ret;
}



/*------------------------------------------------------------------------*/
/* Release Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on leaving file functions to unlock the volume.
*/

MEMSPACE
void ff_rel_grant (
    _SYNC_t sobj    /* Sync object to be signaled */
)
{
    ReleaseMutex(sobj);     /* Win32 */

//  sig_sem(sobj);          /* uITRON */

//  OSMutexPost(sobj);      /* uC/OS-II */

//  xSemaphoreGive(sobj);   /* FreeRTOS */
}

#endif




#if _USE_LFN == 3   /* LFN with a working buffer on the heap */
/*------------------------------------------------------------------------*/
/* Allocate a memory block                                                */
/*------------------------------------------------------------------------*/
/* If a NULL is returned, the file function fails with FR_NOT_ENOUGH_CORE.
*/

MEMSPACE
void* ff_memalloc ( /* Returns pointer to the allocated memory block */
    UINT msize      /* Number of bytes to allocate */
)
{
    return safemalloc(msize);   /* Allocate a new memory block with POSIX API */
}


/*------------------------------------------------------------------------*/
/* Free a memory block                                                    */
/*------------------------------------------------------------------------*/

MEMSPACE
void ff_memfree (
    void* mblock    /* Pointer to the memory block to free */
)
{
    safefree(mblock);   /* Discard the memory block with POSIX API */
}

#endif