ffsystem.c

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/*------------------------------------------------------------------------*/
/* Sample Code of OS Dependent Functions for FatFs                        */
/* (C)ChaN, 2017                                                          */
/*------------------------------------------------------------------------*/


#include "ff.h"



#if FF_USE_LFN == 3 /* Dynamic memory allocation */

/*------------------------------------------------------------------------*/
/* Allocate a memory block                                                */
/*------------------------------------------------------------------------*/

void* ff_memalloc ( /* Returns pointer to the allocated memory block (null on not enough core) */
    UINT msize      /* Number of bytes to allocate */
)
{
    return malloc(msize);   /* Allocate a new memory block with POSIX API */
}


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

void ff_memfree (
    void* mblock    /* Pointer to the memory block to free (nothing to do for null) */
)
{
    free(mblock);   /* Free the memory block with POSIX API */
}

#endif



#if FF_FS_REENTRANT /* Mutal exclusion */

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

//const osMutexDef_t Mutex[FF_VOLUMES]; /* CMSIS-RTOS */


int ff_cre_syncobj (    /* 1:Function succeeded, 0:Could not create the sync object */
    BYTE vol,           /* Corresponding volume (logical drive number) */
    FF_SYNC_t* sobj     /* Pointer to return the created sync object */
)
{
    /* Win32 */
    *sobj = CreateMutex(NULL, FALSE, NULL);
    return (int)(*sobj != INVALID_HANDLE_VALUE);

    /* uITRON */
//  T_CSEM csem = {TA_TPRI,1,1};
//  *sobj = acre_sem(&csem);
//  return (int)(*sobj > 0);

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

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

    /* CMSIS-RTOS */
//  *sobj = osMutexCreate(Mutex + vol);
//  return (int)(*sobj != NULL);
}


/*------------------------------------------------------------------------*/
/* 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.
*/

int ff_del_syncobj (    /* 1:Function succeeded, 0:Could not delete due to an error */
    FF_SYNC_t sobj      /* Sync object tied to the logical drive to be deleted */
)
{
    /* Win32 */
    return (int)CloseHandle(sobj);

    /* uITRON */
//  return (int)(del_sem(sobj) == E_OK);

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

    /* FreeRTOS */
//  vSemaphoreDelete(sobj);
//  return 1;

    /* CMSIS-RTOS */
//  return (int)(osMutexDelete(sobj) == osOK);
}


/*------------------------------------------------------------------------*/
/* 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.
*/

int ff_req_grant (  /* 1:Got a grant to access the volume, 0:Could not get a grant */
    FF_SYNC_t sobj  /* Sync object to wait */
)
{
    /* Win32 */
    return (int)(WaitForSingleObject(sobj, FF_FS_TIMEOUT) == WAIT_OBJECT_0);

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

    /* uC/OS-II */
//  OS_ERR err;
//  OSMutexPend(sobj, FF_FS_TIMEOUT, &err));
//  return (int)(err == OS_NO_ERR);

    /* FreeRTOS */
//  return (int)(xSemaphoreTake(sobj, FF_FS_TIMEOUT) == pdTRUE);

    /* CMSIS-RTOS */
//  return (int)(osMutexWait(sobj, FF_FS_TIMEOUT) == osOK);
}


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

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

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

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

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

    /* CMSIS-RTOS */
//  osMutexRelease(sobj);
}

#endif